Revisit the architecture of CompilerCache

Fixes #5912

src/Microsoft.AspNetCore.Mvc.Razor/Compilation/CompilationResult.cs

@@ -1,72 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using System;
-using System.Collections.Generic;
-using Microsoft.AspNetCore.Diagnostics;
-
-namespace Microsoft.AspNetCore.Mvc.Razor.Compilation
-{
-    /// <summary>
-    /// Represents the result of compilation.
-    /// </summary>
-    public struct CompilationResult
-    {
-        /// <summary>
-        /// Initializes a new instance of <see cref="CompilationResult"/> for a successful compilation.
-        /// </summary>
-        /// <param name="type">The compiled type.</param>
-        public CompilationResult(Type type)
-        {
-            if (type == null)
-            {
-                throw new ArgumentNullException(nameof(type));
-            }
-
-            CompiledType = type;
-            CompilationFailures = null;
-        }
-
-        /// <summary>
-        /// Initializes a new instance of <see cref="CompilationResult"/> for a failed compilation.
-        /// </summary>
-        /// <param name="compilationFailures"><see cref="CompilationFailure"/>s produced from parsing or
-        /// compiling the Razor file.</param>
-        public CompilationResult(IEnumerable<CompilationFailure> compilationFailures)
-        {
-            if (compilationFailures == null)
-            {
-                throw new ArgumentNullException(nameof(compilationFailures));
-            }
-
-            CompiledType = null;
-            CompilationFailures = compilationFailures;
-        }
-
-        /// <summary>
-        /// Gets the type produced as a result of compilation.
-        /// </summary>
-        /// <remarks>This property is <c>null</c> when compilation failed.</remarks>
-        public Type CompiledType { get; }
-
-        /// <summary>
-        /// Gets the <see cref="CompilationFailure"/>s produced from parsing or compiling the Razor file.
-        /// </summary>
-        /// <remarks>This property is <c>null</c> when compilation succeeded. An empty sequence
-        /// indicates a failed compilation.</remarks>
-        public IEnumerable<CompilationFailure> CompilationFailures { get; }
-
-        /// <summary>
-        /// Gets the <see cref="CompilationResult"/>.
-        /// </summary>
-        /// <returns>The current <see cref="CompilationResult"/> instance.</returns>
-        /// <exception cref="CompilationFailedException">Thrown if compilation failed.</exception>
-        public void EnsureSuccessful()
-        {
-            if (CompilationFailures != null)
-            {
-                throw new CompilationFailedException(CompilationFailures);
-            }
-        }
-    }
-}

src/Microsoft.AspNetCore.Mvc.Razor/Compilation/CompiledViewDescriptor.cs

@@ -0,0 +1,28 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System.Collections.Generic;
+using Microsoft.Extensions.Primitives;
+
+namespace Microsoft.AspNetCore.Mvc.Razor.Compilation
+{
+    public class CompiledViewDescriptor
+    {
+        public string RelativePath { get; set; }
+
+        /// <summary>
+        /// Gets or sets the <see cref="RazorViewAttribute"/> decorating the sview.
+        /// </summary>
+        public RazorViewAttribute ViewAttribute { get; set; }
+
+        /// <summary>
+        /// <see cref="IChangeToken"/> instances that indicate when this result has expired.
+        /// </summary>
+        public IList<IChangeToken> ExpirationTokens { get; set; }
+
+        /// <summary>
+        /// Gets a value that determines if the view is precompiled.
+        /// </summary>
+        public bool IsPrecompiled { get; set; }
+    }
+}

src/Microsoft.AspNetCore.Mvc.Razor/Compilation/ICompilationService.cs

@@ -1,27 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using Microsoft.AspNetCore.Razor.Language;
-
-namespace Microsoft.AspNetCore.Mvc.Razor.Compilation
-{
-    /// <summary>
-    /// Provides methods for compilation of a Razor page.
-    /// </summary>
-    public interface ICompilationService
-    {
-        /// <summary>
-        /// Compiles a <see cref="RazorCSharpDocument"/>  and returns the result of compilation.
-        /// </summary>
-        /// <param name="codeDocument">
-        /// The <see cref="RazorCodeDocument"/> that contains the sources for the compilation. 
-        /// </param>
-        /// <param name="cSharpDocument">
-        /// The <see cref="RazorCSharpDocument"/> to compile. 
-        /// </param>
-        /// <returns>
-        /// A <see cref="CompilationResult"/> representing the result of compilation.
-        /// </returns>
-        CompilationResult Compile(RazorCodeDocument codeDocument, RazorCSharpDocument cSharpDocument);
-    }
-}

src/Microsoft.AspNetCore.Mvc.Razor/Compilation/IViewCompiler.cs

@@ -0,0 +1,12 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System.Threading.Tasks;
+
+namespace Microsoft.AspNetCore.Mvc.Razor.Compilation
+{
+    public interface IViewCompiler
+    {
+        Task<CompiledViewDescriptor> CompileAsync(string relativePath);
+    }
+}

src/Microsoft.AspNetCore.Mvc.Razor/Compilation/IViewCompilerProvider.cs

@@ -0,0 +1,10 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+namespace Microsoft.AspNetCore.Mvc.Razor.Compilation
+{
+    public interface IViewCompilerProvider
+    {
+        IViewCompiler GetCompiler();
+    }
+}

src/Microsoft.AspNetCore.Mvc.Razor/Compilation/RazorViewAttribute.cs

@@ -0,0 +1,27 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System;
+
+namespace Microsoft.AspNetCore.Mvc.Razor.Compilation
+{
+    [AttributeUsage(AttributeTargets.Assembly, AllowMultiple = true)]
+    public class RazorViewAttribute : Attribute
+    {
+        public RazorViewAttribute(string path, Type viewType)
+        {
+            Path = path;
+            ViewType = viewType;
+        }
+
+        /// <summary>
+        /// Gets the path of the view.
+        /// </summary>
+        public string Path { get; }
+
+        /// <summary>
+        /// Gets the view type.
+        /// </summary>
+        public Type ViewType { get; }
+    }
+}

src/Microsoft.AspNetCore.Mvc.Razor/Compilation/ViewsFeature.cs

@@ -1,14 +1,12 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
-using System;
 using System.Collections.Generic;
 
 namespace Microsoft.AspNetCore.Mvc.Razor.Compilation
 {
     public class ViewsFeature
     {
-        public IDictionary<string, Type> Views { get; } =
+        public IList<CompiledViewDescriptor> ViewDescriptors { get; } = new List<CompiledViewDescriptor>();
-            new Dictionary<string, Type>(StringComparer.OrdinalIgnoreCase);
     }
 }

src/Microsoft.AspNetCore.Mvc.Razor/Compilation/ViewsFeatureProvider.cs

@@ -5,6 +5,8 @@ using System;
 using System.Collections.Generic;
 using System.Linq;
 using Microsoft.AspNetCore.Mvc.ApplicationParts;
+using Microsoft.AspNetCore.Mvc.Razor.Internal;
+using Microsoft.Extensions.Primitives;
 
 namespace Microsoft.AspNetCore.Mvc.Razor.Compilation
 {
@@ -40,7 +42,16 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Compilation
 
                 foreach (var item in viewContainer.ViewInfos)
                 {
-                    feature.Views[item.Path] = item.Type;
+                    var relativePath = ViewPath.NormalizePath(item.Path);
+                    var viewDescriptor = new CompiledViewDescriptor
+                    {
+                        ExpirationTokens = Array.Empty<IChangeToken>(),
+                        RelativePath = relativePath,
+                        ViewAttribute = new RazorViewAttribute(relativePath, item.Type),
+                        IsPrecompiled = true,
+                    };
+
+                    feature.ViewDescriptors.Add(viewDescriptor);
                 }
             }
         }

src/Microsoft.AspNetCore.Mvc.Razor/DependencyInjection/MvcRazorMvcCoreBuilderExtensions.cs

@@ -134,7 +134,6 @@ namespace Microsoft.Extensions.DependencyInjection
             services.TryAddSingleton<CSharpCompiler>();
             services.TryAddSingleton<RazorReferenceManager>();
             // This caches compilation related details that are valid across the lifetime of the application.
-            services.TryAddSingleton<ICompilationService, DefaultRoslynCompilationService>();
 
             services.TryAddEnumerable(
                 ServiceDescriptor.Transient<IConfigureOptions<MvcViewOptions>, MvcRazorMvcViewOptionsSetup>());
@@ -153,9 +152,7 @@ namespace Microsoft.Extensions.DependencyInjection
                 DefaultRazorViewEngineFileProviderAccessor>();
 
             services.TryAddSingleton<IRazorViewEngine, RazorViewEngine>();
-
+            services.TryAddSingleton<IViewCompilerProvider, RazorViewCompilerProvider>();
-            // Caches compilation artifacts across the lifetime of the application.
-            services.TryAddSingleton<ICompilerCacheProvider, DefaultCompilerCacheProvider>();
 
             // In the default scenario the following services are singleton by virtue of being initialized as part of
             // creating the singleton RazorViewEngine instance.
@@ -166,7 +163,6 @@ namespace Microsoft.Extensions.DependencyInjection
             //
             services.TryAddSingleton<RazorProject, FileProviderRazorProject>();
             services.TryAddSingleton<RazorTemplateEngine, MvcRazorTemplateEngine>();
-            services.TryAddSingleton<RazorCompiler>();
             services.TryAddSingleton<LazyMetadataReferenceFeature>();
 
             services.TryAddSingleton<RazorEngine>(s =>

src/Microsoft.AspNetCore.Mvc.Razor/Internal/CompilationFailedExceptionFactory.cs

@@ -0,0 +1,159 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using Microsoft.AspNetCore.Diagnostics;
+using Microsoft.AspNetCore.Mvc.Razor.Compilation;
+using Microsoft.AspNetCore.Razor.Language;
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp;
+
+namespace Microsoft.AspNetCore.Mvc.Razor.Internal
+{
+    internal static class CompilationFailedExceptionFactory
+    {
+        // error CS0234: The type or namespace name 'C' does not exist in the namespace 'N' (are you missing
+        // an assembly reference?)
+        private const string CS0234 = nameof(CS0234);
+        // error CS0246: The type or namespace name 'T' could not be found (are you missing a using directive
+        // or an assembly reference?)
+        private const string CS0246 = nameof(CS0246);
+
+        public static CompilationFailedException Create(
+            RazorCodeDocument codeDocument,
+            IEnumerable<RazorDiagnostic> diagnostics)
+        {
+            // If a SourceLocation does not specify a file path, assume it is produced from parsing the current file.
+            var messageGroups = diagnostics.GroupBy(
+                razorError => razorError.Span.FilePath ?? codeDocument.Source.FileName,
+                StringComparer.Ordinal);
+
+            var failures = new List<CompilationFailure>();
+            foreach (var group in messageGroups)
+            {
+                var filePath = group.Key;
+                var fileContent = ReadContent(codeDocument, filePath);
+                var compilationFailure = new CompilationFailure(
+                    filePath,
+                    fileContent,
+                    compiledContent: string.Empty,
+                    messages: group.Select(parserError => CreateDiagnosticMessage(parserError, filePath)));
+                failures.Add(compilationFailure);
+            }
+
+            return new CompilationFailedException(failures);
+        }
+
+        public static CompilationFailedException Create(
+            RazorCodeDocument codeDocument,
+            string compilationContent,
+            string assemblyName,
+            IEnumerable<Diagnostic> diagnostics)
+        {
+            var diagnosticGroups = diagnostics
+                .Where(diagnostic => diagnostic.IsWarningAsError || diagnostic.Severity == DiagnosticSeverity.Error)
+                .GroupBy(diagnostic => GetFilePath(codeDocument, diagnostic), StringComparer.Ordinal);
+
+            var failures = new List<CompilationFailure>();
+            foreach (var group in diagnosticGroups)
+            {
+                var sourceFilePath = group.Key;
+                string sourceFileContent;
+                if (string.Equals(assemblyName, sourceFilePath, StringComparison.Ordinal))
+                {
+                    // The error is in the generated code and does not have a mapping line pragma
+                    sourceFileContent = compilationContent;
+                    sourceFilePath = Resources.GeneratedCodeFileName;
+                }
+                else
+                {
+                    sourceFileContent = ReadContent(codeDocument, sourceFilePath);
+                }
+
+                string additionalMessage = null;
+                if (group.Any(g =>
+                    string.Equals(CS0234, g.Id, StringComparison.OrdinalIgnoreCase) ||
+                    string.Equals(CS0246, g.Id, StringComparison.OrdinalIgnoreCase)))
+                {
+                    additionalMessage = Resources.FormatCompilation_DependencyContextIsNotSpecified(
+                        "Microsoft.NET.Sdk.Web",
+                        "PreserveCompilationContext");
+                }
+
+                var compilationFailure = new CompilationFailure(
+                    sourceFilePath,
+                    sourceFileContent,
+                    compilationContent,
+                    group.Select(GetDiagnosticMessage),
+                    additionalMessage);
+
+                failures.Add(compilationFailure);
+            }
+
+            return new CompilationFailedException(failures);
+        }
+
+        private static string ReadContent(RazorCodeDocument codeDocument, string filePath)
+        {
+            RazorSourceDocument sourceDocument = null;
+            if (string.IsNullOrEmpty(filePath) || string.Equals(codeDocument.Source.FileName, filePath, StringComparison.Ordinal))
+            {
+                sourceDocument = codeDocument.Source;
+            }
+            else
+            {
+                sourceDocument = codeDocument.Imports.FirstOrDefault(f => string.Equals(f.FileName, filePath, StringComparison.Ordinal));
+            }
+
+            if (sourceDocument != null)
+            {
+                var contentChars = new char[sourceDocument.Length];
+                sourceDocument.CopyTo(0, contentChars, 0, sourceDocument.Length);
+                return new string(contentChars);
+            }
+
+            return string.Empty;
+        }
+
+        private static DiagnosticMessage GetDiagnosticMessage(Diagnostic diagnostic)
+        {
+            var mappedLineSpan = diagnostic.Location.GetMappedLineSpan();
+            return new DiagnosticMessage(
+                diagnostic.GetMessage(),
+                CSharpDiagnosticFormatter.Instance.Format(diagnostic),
+                mappedLineSpan.Path,
+                mappedLineSpan.StartLinePosition.Line + 1,
+                mappedLineSpan.StartLinePosition.Character + 1,
+                mappedLineSpan.EndLinePosition.Line + 1,
+                mappedLineSpan.EndLinePosition.Character + 1);
+        }
+
+        private static DiagnosticMessage CreateDiagnosticMessage(
+            RazorDiagnostic razorDiagnostic,
+            string filePath)
+        {
+            var sourceSpan = razorDiagnostic.Span;
+            var message = razorDiagnostic.GetMessage();
+            return new DiagnosticMessage(
+                message: message,
+                formattedMessage: razorDiagnostic.ToString(),
+                filePath: filePath,
+                startLine: sourceSpan.LineIndex + 1,
+                startColumn: sourceSpan.CharacterIndex,
+                endLine: sourceSpan.LineIndex + 1,
+                endColumn: sourceSpan.CharacterIndex + sourceSpan.Length);
+        }
+
+        private static string GetFilePath(RazorCodeDocument codeDocument, Diagnostic diagnostic)
+        {
+            if (diagnostic.Location == Location.None)
+            {
+                return codeDocument.Source.FileName;
+            }
+
+            return diagnostic.Location.GetMappedLineSpan().Path;
+        }
+    }
+}

src/Microsoft.AspNetCore.Mvc.Razor/Internal/CompilerCache.cs

@@ -1,194 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using System;
-using System.Collections.Concurrent;
-using System.Collections.Generic;
-using System.Diagnostics;
-using System.Text;
-using System.Threading.Tasks;
-using Microsoft.AspNetCore.Mvc.Razor.Compilation;
-using Microsoft.Extensions.Caching.Memory;
-using Microsoft.Extensions.FileProviders;
-
-namespace Microsoft.AspNetCore.Mvc.Razor.Internal
-{
-    /// <summary>
-    /// Caches the result of runtime compilation of Razor files for the duration of the application lifetime.
-    /// </summary>
-    public class CompilerCache : ICompilerCache
-    {
-        private readonly IFileProvider _fileProvider;
-        private readonly IMemoryCache _cache;
-        private readonly object _cacheLock = new object();
-
-        private readonly ConcurrentDictionary<string, string> _normalizedPathLookup =
-            new ConcurrentDictionary<string, string>(StringComparer.Ordinal);
-
-        /// <summary>
-        /// Initializes a new instance of <see cref="CompilerCache"/>.
-        /// </summary>
-        /// <param name="fileProvider"><see cref="IFileProvider"/> used to locate Razor views.</param>
-        public CompilerCache(IFileProvider fileProvider)
-        {
-            if (fileProvider == null)
-            {
-                throw new ArgumentNullException(nameof(fileProvider));
-            }
-
-            _fileProvider = fileProvider;
-            _cache = new MemoryCache(new MemoryCacheOptions());
-        }
-
-        /// <summary>
-        /// Initializes a new instance of <see cref="CompilerCache"/> populated with precompiled views
-        /// specified by <paramref name="views"/>.
-        /// </summary>
-        /// <param name="fileProvider"><see cref="IFileProvider"/> used to locate Razor views.</param>
-        /// <param name="views">A mapping of application relative paths of view to <see cref="Type"/>s that
-        /// have already been compiled.</param>
-        public CompilerCache(
-            IFileProvider fileProvider,
-            IDictionary<string, Type> views)
-            : this(fileProvider)
-        {
-            if (views == null)
-            {
-                throw new ArgumentNullException(nameof(views));
-            }
-
-            foreach (var item in views)
-            {
-                var cacheEntry = new CompilerCacheResult(item.Key, new CompilationResult(item.Value), isPrecompiled: true);
-                _cache.Set(GetNormalizedPath(item.Key), Task.FromResult(cacheEntry));
-            }
-        }
-
-        /// <inheritdoc />
-        public CompilerCacheResult GetOrAdd(
-            string relativePath,
-            Func<string, CompilerCacheContext> cacheContextFactory)
-        {
-            if (relativePath == null)
-            {
-                throw new ArgumentNullException(nameof(relativePath));
-            }
-
-            if (cacheContextFactory == null)
-            {
-                throw new ArgumentNullException(nameof(cacheContextFactory));
-            }
-
-            Task<CompilerCacheResult> cacheEntry;
-            // Attempt to lookup the cache entry using the passed in path. This will succeed if the path is already
-            // normalized and a cache entry exists.
-            if (!_cache.TryGetValue(relativePath, out cacheEntry))
-            {
-                var normalizedPath = GetNormalizedPath(relativePath);
-                if (!_cache.TryGetValue(normalizedPath, out cacheEntry))
-                {
-                    cacheEntry = CreateCacheEntry(normalizedPath, cacheContextFactory);
-                }
-            }
-
-            // The Task does not represent async work and is meant to provide per-entry locking.
-            // Hence it is ok to perform .GetResult() to read the result.
-            return cacheEntry.GetAwaiter().GetResult();
-        }
-
-        private Task<CompilerCacheResult> CreateCacheEntry(
-            string normalizedPath,
-            Func<string, CompilerCacheContext> cacheContextFactory)
-        {
-            TaskCompletionSource<CompilerCacheResult> compilationTaskSource = null;
-            MemoryCacheEntryOptions cacheEntryOptions;
-            Task<CompilerCacheResult> cacheEntry;
-            CompilerCacheContext compilerCacheContext;
-
-            // Safe races cannot be allowed when compiling Razor pages. To ensure only one compilation request succeeds
-            // per file, we'll lock the creation of a cache entry. Creating the cache entry should be very quick. The
-            // actual work for compiling files happens outside the critical section.
-            lock (_cacheLock)
-            {
-                if (_cache.TryGetValue(normalizedPath, out cacheEntry))
-                {
-                    return cacheEntry;
-                }
-
-                if (_fileProvider is NullFileProvider)
-                {
-                    var message = Resources.FormatFileProvidersAreRequired(
-                        typeof(RazorViewEngineOptions).FullName,
-                        nameof(RazorViewEngineOptions.FileProviders),
-                        typeof(IFileProvider).FullName);
-                    throw new InvalidOperationException(message);
-                }
-
-                cacheEntryOptions = new MemoryCacheEntryOptions();
-
-                compilerCacheContext = cacheContextFactory(normalizedPath);
-                cacheEntryOptions.ExpirationTokens.Add(_fileProvider.Watch(compilerCacheContext.ProjectItem.Path));
-                if (!compilerCacheContext.ProjectItem.Exists)
-                {
-                    cacheEntry = Task.FromResult(new CompilerCacheResult(normalizedPath, cacheEntryOptions.ExpirationTokens));
-                }
-                else
-                {
-                    // A file exists and needs to be compiled.
-                    compilationTaskSource = new TaskCompletionSource<CompilerCacheResult>();
-                    foreach (var projectItem in compilerCacheContext.AdditionalCompilationItems)
-                    {
-                        cacheEntryOptions.ExpirationTokens.Add(_fileProvider.Watch(projectItem.Path));
-                    }
-                    cacheEntry = compilationTaskSource.Task;
-                }
-
-                cacheEntry = _cache.Set(normalizedPath, cacheEntry, cacheEntryOptions);
-            }
-
-            if (compilationTaskSource != null)
-            {
-                // Indicates that a file was found and needs to be compiled.
-                Debug.Assert(cacheEntryOptions != null);
-
-                try
-                {
-                    var compilationResult = compilerCacheContext.Compile(compilerCacheContext);
-                    compilationResult.EnsureSuccessful();
-                    compilationTaskSource.SetResult(
-                        new CompilerCacheResult(normalizedPath, compilationResult, cacheEntryOptions.ExpirationTokens));
-                }
-                catch (Exception ex)
-                {
-                    compilationTaskSource.SetException(ex);
-                }
-            }
-
-            return cacheEntry;
-        }
-
-        private string GetNormalizedPath(string relativePath)
-        {
-            Debug.Assert(relativePath != null);
-            if (relativePath.Length == 0)
-            {
-                return relativePath;
-            }
-
-            string normalizedPath;
-            if (!_normalizedPathLookup.TryGetValue(relativePath, out normalizedPath))
-            {
-                var builder = new StringBuilder(relativePath);
-                builder.Replace('\\', '/');
-                if (builder[0] != '/')
-                {
-                    builder.Insert(0, '/');
-                }
-                normalizedPath = builder.ToString();
-                _normalizedPathLookup.TryAdd(relativePath, normalizedPath);
-            }
-
-            return normalizedPath;
-        }
-    }
-}

src/Microsoft.AspNetCore.Mvc.Razor/Internal/CompilerCacheContext.cs

@@ -1,29 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using System;
-using System.Collections.Generic;
-using Microsoft.AspNetCore.Mvc.Razor.Compilation;
-using Microsoft.AspNetCore.Razor.Language;
-
-namespace Microsoft.AspNetCore.Mvc.Razor.Internal
-{
-    public struct CompilerCacheContext
-    {
-        public CompilerCacheContext(
-            RazorProjectItem projectItem,
-            IEnumerable<RazorProjectItem> additionalCompilationItems,
-            Func<CompilerCacheContext, CompilationResult> compile)
-        {
-            ProjectItem = projectItem;
-            AdditionalCompilationItems = additionalCompilationItems;
-            Compile = compile;
-        }
-
-        public RazorProjectItem ProjectItem { get; }
-
-        public IEnumerable<RazorProjectItem> AdditionalCompilationItems { get; }
-
-        public Func<CompilerCacheContext, CompilationResult> Compile { get; }
-    }
-}

src/Microsoft.AspNetCore.Mvc.Razor/Internal/CompilerCacheResult.cs

@@ -1,96 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using System;
-using System.Collections.Generic;
-using Microsoft.AspNetCore.Mvc.Internal;
-using Microsoft.AspNetCore.Mvc.Razor.Compilation;
-using Microsoft.Extensions.Primitives;
-
-namespace Microsoft.AspNetCore.Mvc.Razor.Internal
-{
-    /// <summary>
-    /// Result of <see cref="ICompilerCache"/>.
-    /// </summary>
-    public struct CompilerCacheResult
-    {
-        /// <summary>
-        /// Initializes a new instance of <see cref="CompilerCacheResult"/> with the specified
-        /// <see cref="CompilationResult"/>.
-        /// </summary>
-        /// <param name="relativePath">Path of the view file relative to the application base.</param>
-        /// <param name="compilationResult">The <see cref="CompilationResult"/>.</param>
-        /// <param name="isPrecompiled"><c>true</c> if the view is precompiled, <c>false</c> otherwise.</param>
-        public CompilerCacheResult(string relativePath, CompilationResult compilationResult, bool isPrecompiled)
-            : this(relativePath, compilationResult, Array.Empty<IChangeToken>())
-        {
-            IsPrecompiled = isPrecompiled;
-        }
-
-        /// <summary>
-        /// Initializes a new instance of <see cref="CompilerCacheResult"/> with the specified
-        /// <see cref="CompilationResult"/>.
-        /// </summary>
-        /// <param name="relativePath">Path of the view file relative to the application base.</param>
-        /// <param name="compilationResult">The <see cref="CompilationResult"/>.</param>
-        /// <param name="expirationTokens">One or more <see cref="IChangeToken"/> instances that indicate when
-        /// this result has expired.</param>
-        public CompilerCacheResult(string relativePath, CompilationResult compilationResult, IList<IChangeToken> expirationTokens)
-        {
-            if (expirationTokens == null)
-            {
-                throw new ArgumentNullException(nameof(expirationTokens));
-            }
-
-            RelativePath = relativePath;
-            CompiledType = compilationResult.CompiledType;
-            ExpirationTokens = expirationTokens;
-            IsPrecompiled = false;
-        }
-
-        /// <summary>
-        /// Initializes a new instance of <see cref="CompilerCacheResult"/> for a file that could not be
-        /// found in the file system.
-        /// </summary>
-        /// <param name="relativePath">Path of the view file relative to the application base.</param>
-        /// <param name="expirationTokens">One or more <see cref="IChangeToken"/> instances that indicate when
-        /// this result has expired.</param>
-        public CompilerCacheResult(string relativePath, IList<IChangeToken> expirationTokens)
-        {
-            if (expirationTokens == null)
-            {
-                throw new ArgumentNullException(nameof(expirationTokens));
-            }
-
-            ExpirationTokens = expirationTokens;
-            RelativePath = null;
-            CompiledType = null;
-            IsPrecompiled = false;
-        }
-
-        /// <summary>
-        /// <see cref="IChangeToken"/> instances that indicate when this result has expired.
-        /// </summary>
-        public IList<IChangeToken> ExpirationTokens { get; }
-
-        /// <summary>
-        /// Gets a value that determines if the view was successfully found and compiled.
-        /// </summary>
-        public bool Success => CompiledType != null;
-
-        /// <summary>
-        /// Normalized relative path of the file.
-        /// </summary>
-        public string RelativePath { get; }
-
-        /// <summary>
-        /// The compiled <see cref="Type"/>.
-        /// </summary>
-        public Type CompiledType { get; }
-
-        /// <summary>
-        /// Gets a value that determines if the view is precompiled.
-        /// </summary>
-        public bool IsPrecompiled { get; }
-    }
-}

src/Microsoft.AspNetCore.Mvc.Razor/Internal/DefaultCompilerCacheProvider.cs

@@ -1,31 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using Microsoft.AspNetCore.Mvc.ApplicationParts;
-using Microsoft.AspNetCore.Mvc.Razor.Compilation;
-
-namespace Microsoft.AspNetCore.Mvc.Razor.Internal
-{
-    /// <summary>
-    /// Default implementation for <see cref="ICompilerCacheProvider"/>.
-    /// </summary>
-    public class DefaultCompilerCacheProvider : ICompilerCacheProvider
-    {
-        /// <summary>
-        /// Initializes a new instance of <see cref="DefaultCompilerCacheProvider"/>.
-        /// </summary>
-        /// <param name="applicationPartManager">The <see cref="ApplicationPartManager" /></param>
-        /// <param name="fileProviderAccessor">The <see cref="IRazorViewEngineFileProviderAccessor"/>.</param>
-        public DefaultCompilerCacheProvider(
-            ApplicationPartManager applicationPartManager,
-            IRazorViewEngineFileProviderAccessor fileProviderAccessor)
-        {
-            var feature = new ViewsFeature();
-            applicationPartManager.PopulateFeature(feature);
-            Cache = new CompilerCache(fileProviderAccessor.FileProvider, feature.Views);
-        }
-
-        /// <inheritdoc />
-        public ICompilerCache Cache { get; }
-    }
-}

src/Microsoft.AspNetCore.Mvc.Razor/Internal/DefaultRazorPageFactoryProvider.cs

@@ -4,6 +4,7 @@
 using System;
 using System.Linq.Expressions;
 using System.Reflection;
+using Microsoft.AspNetCore.Mvc.Razor.Compilation;
 
 namespace Microsoft.AspNetCore.Mvc.Razor.Internal
 {
@@ -13,17 +14,19 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Internal
     /// </summary>
     public class DefaultRazorPageFactoryProvider : IRazorPageFactoryProvider
     {
-        private readonly RazorCompiler _compiler;
+        private readonly IViewCompilerProvider _viewCompilerProvider;
 
         /// <summary>
         /// Initializes a new instance of <see cref="DefaultRazorPageFactoryProvider"/>.
         /// </summary>
-        /// <param name="compiler">The <see cref="RazorCompiler"/>.</param>
+        /// <param name="viewCompilerProvider">The <see cref="IViewCompilerProvider"/>.</param>
-        public DefaultRazorPageFactoryProvider(RazorCompiler compiler)
+        public DefaultRazorPageFactoryProvider(IViewCompilerProvider viewCompilerProvider)
         {
-            _compiler = compiler;
+            _viewCompilerProvider = viewCompilerProvider;
         }
 
+        private IViewCompiler Compiler => _viewCompilerProvider.GetCompiler();
+
         /// <inheritdoc />
         public RazorPageFactoryResult CreateFactory(string relativePath)
         {
@@ -38,26 +41,27 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Internal
                 relativePath = relativePath.Substring(1);
             }
 
-            var result = _compiler.Compile(relativePath);
+            var compileTask = Compiler.CompileAsync(relativePath);
-            if (result.Success)
+            var viewDescriptor = compileTask.GetAwaiter().GetResult();
+            if (viewDescriptor.ViewAttribute != null)
             {
-                var compiledType = result.CompiledType;
+                var compiledType = viewDescriptor.ViewAttribute.ViewType;
 
                 var newExpression = Expression.New(compiledType);
                 var pathProperty = compiledType.GetTypeInfo().GetProperty(nameof(IRazorPage.Path));
 
                 // Generate: page.Path = relativePath;
                 // Use the normalized path specified from the result.
-                var propertyBindExpression = Expression.Bind(pathProperty, Expression.Constant(result.RelativePath));
+                var propertyBindExpression = Expression.Bind(pathProperty, Expression.Constant(viewDescriptor.RelativePath));
                 var objectInitializeExpression = Expression.MemberInit(newExpression, propertyBindExpression);
                 var pageFactory = Expression
                     .Lambda<Func<IRazorPage>>(objectInitializeExpression)
                     .Compile();
-                return new RazorPageFactoryResult(pageFactory, result.ExpirationTokens, result.IsPrecompiled);
+                return new RazorPageFactoryResult(pageFactory, viewDescriptor.ExpirationTokens, viewDescriptor.IsPrecompiled);
             }
             else
             {
-                return new RazorPageFactoryResult(result.ExpirationTokens);
+                return new RazorPageFactoryResult(viewDescriptor.ExpirationTokens);
             }
         }
     }

src/Microsoft.AspNetCore.Mvc.Razor/Internal/DefaultRoslynCompilationService.cs

@@ -1,228 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using System;
-using System.Collections.Generic;
-using System.Diagnostics;
-using System.IO;
-using System.Linq;
-using System.Reflection;
-using System.Runtime.Loader;
-using System.Text;
-using Microsoft.AspNetCore.Diagnostics;
-using Microsoft.AspNetCore.Mvc.Razor.Compilation;
-using Microsoft.AspNetCore.Razor.Language;
-using Microsoft.CodeAnalysis;
-using Microsoft.CodeAnalysis.CSharp;
-using Microsoft.CodeAnalysis.Text;
-using Microsoft.Extensions.Logging;
-using Microsoft.Extensions.Options;
-
-namespace Microsoft.AspNetCore.Mvc.Razor.Internal
-{
-    /// <summary>
-    /// A type that uses Roslyn to compile C# content.
-    /// </summary>
-    public class DefaultRoslynCompilationService : ICompilationService
-    {
-        // error CS0234: The type or namespace name 'C' does not exist in the namespace 'N' (are you missing
-        // an assembly reference?)
-        private const string CS0234 = nameof(CS0234);
-        // error CS0246: The type or namespace name 'T' could not be found (are you missing a using directive
-        // or an assembly reference?)
-        private const string CS0246 = nameof(CS0246);
-
-        private readonly CSharpCompiler _compiler;
-        private readonly ILogger _logger;
-        private readonly Action<RoslynCompilationContext> _compilationCallback;
-
-        /// <summary>
-        /// Initalizes a new instance of the <see cref="DefaultRoslynCompilationService"/> class.
-        /// </summary>
-        /// <param name="compiler">The <see cref="CSharpCompiler"/>.</param>
-        /// <param name="optionsAccessor">Accessor to <see cref="RazorViewEngineOptions"/>.</param>
-        /// <param name="loggerFactory">The <see cref="ILoggerFactory"/>.</param>
-        public DefaultRoslynCompilationService(
-            CSharpCompiler compiler,
-            IOptions<RazorViewEngineOptions> optionsAccessor,
-            ILoggerFactory loggerFactory)
-        {
-            _compiler = compiler;
-            _compilationCallback = optionsAccessor.Value.CompilationCallback;
-            _logger = loggerFactory.CreateLogger<DefaultRoslynCompilationService>();
-        }
-
-        /// <inheritdoc />
-        public CompilationResult Compile(RazorCodeDocument codeDocument, RazorCSharpDocument cSharpDocument)
-        {
-            if (codeDocument == null)
-            {
-                throw new ArgumentNullException(nameof(codeDocument));
-            }
-
-            if (cSharpDocument == null)
-            {
-                throw new ArgumentNullException(nameof(codeDocument));
-            }
-
-            _logger.GeneratedCodeToAssemblyCompilationStart(codeDocument.Source.FileName);
-
-            var startTimestamp = _logger.IsEnabled(LogLevel.Debug) ? Stopwatch.GetTimestamp() : 0;
-
-            var assemblyName = Path.GetRandomFileName();
-            var compilation = CreateCompilation(cSharpDocument.GeneratedCode, assemblyName);
-
-            using (var assemblyStream = new MemoryStream())
-            {
-                using (var pdbStream = new MemoryStream())
-                {
-                    var result = compilation.Emit(
-                        assemblyStream,
-                        pdbStream,
-                        options: _compiler.EmitOptions);
-
-                    if (!result.Success)
-                    {
-                        return GetCompilationFailedResult(
-                            codeDocument,
-                            cSharpDocument.GeneratedCode,
-                            assemblyName,
-                            result.Diagnostics);
-                    }
-
-                    assemblyStream.Seek(0, SeekOrigin.Begin);
-                    pdbStream.Seek(0, SeekOrigin.Begin);
-
-                    var assembly = LoadAssembly(assemblyStream, pdbStream);
-                    var type = assembly.GetExportedTypes().FirstOrDefault(a => !a.IsNested);
-
-                    _logger.GeneratedCodeToAssemblyCompilationEnd(codeDocument.Source.FileName, startTimestamp);
-
-                    return new CompilationResult(type);
-                }
-            }
-        }
-
-        private CSharpCompilation CreateCompilation(string compilationContent, string assemblyName)
-        {
-            var sourceText = SourceText.From(compilationContent, Encoding.UTF8);
-            var syntaxTree = _compiler.CreateSyntaxTree(sourceText).WithFilePath(assemblyName);
-            var compilation = _compiler
-                .CreateCompilation(assemblyName)
-                .AddSyntaxTrees(syntaxTree);
-            compilation = ExpressionRewriter.Rewrite(compilation);
-
-            var compilationContext = new RoslynCompilationContext(compilation);
-            _compilationCallback(compilationContext);
-            compilation = compilationContext.Compilation;
-            return compilation;
-        }
-
-        // Internal for unit testing
-        internal CompilationResult GetCompilationFailedResult(
-            RazorCodeDocument codeDocument,
-            string compilationContent,
-            string assemblyName,
-            IEnumerable<Diagnostic> diagnostics)
-        {
-            var diagnosticGroups = diagnostics
-                .Where(IsError)
-                .GroupBy(diagnostic => GetFilePath(codeDocument, diagnostic), StringComparer.Ordinal);
-
-            var failures = new List<CompilationFailure>();
-            foreach (var group in diagnosticGroups)
-            {
-                var sourceFilePath = group.Key;
-                string sourceFileContent;
-                if (string.Equals(assemblyName, sourceFilePath, StringComparison.Ordinal))
-                {
-                    // The error is in the generated code and does not have a mapping line pragma
-                    sourceFileContent = compilationContent;
-                    sourceFilePath = Resources.GeneratedCodeFileName;
-                }
-                else
-                {
-                    sourceFileContent = GetContent(codeDocument, sourceFilePath);
-                }
-
-                string additionalMessage = null;
-                if (group.Any(g =>
-                    string.Equals(CS0234, g.Id, StringComparison.OrdinalIgnoreCase) ||
-                    string.Equals(CS0246, g.Id, StringComparison.OrdinalIgnoreCase)))
-                {
-                    additionalMessage = Resources.FormatCompilation_DependencyContextIsNotSpecified(
-                        "Microsoft.NET.Sdk.Web",
-                        "PreserveCompilationContext");
-                }
-
-                var compilationFailure = new CompilationFailure(
-                    sourceFilePath,
-                    sourceFileContent,
-                    compilationContent,
-                    group.Select(GetDiagnosticMessage),
-                    additionalMessage);
-
-                failures.Add(compilationFailure);
-            }
-
-            return new CompilationResult(failures);
-        }
-
-        private static string GetFilePath(RazorCodeDocument codeDocument, Diagnostic diagnostic)
-        {
-            if (diagnostic.Location == Location.None)
-            {
-                return codeDocument.Source.FileName;
-            }
-
-            return diagnostic.Location.GetMappedLineSpan().Path;
-        }
-
-        private static bool IsError(Diagnostic diagnostic)
-        {
-            return diagnostic.IsWarningAsError || diagnostic.Severity == DiagnosticSeverity.Error;
-        }
-
-        public static Assembly LoadAssembly(MemoryStream assemblyStream, MemoryStream pdbStream)
-        {
-            var assembly = Assembly.Load(assemblyStream.ToArray(), pdbStream.ToArray());
-            return assembly;
-        }
-
-        private static string GetContent(RazorCodeDocument codeDocument, string filePath)
-        {
-            if (filePath == codeDocument.Source.FileName)
-            {
-                var chars = new char[codeDocument.Source.Length];
-                codeDocument.Source.CopyTo(0, chars, 0, chars.Length);
-                return new string(chars);
-            }
-
-            for (var i = 0; i < codeDocument.Imports.Count; i++)
-            {
-                var import = codeDocument.Imports[i];
-                if (filePath == import.FileName)
-                {
-                    var chars = new char[codeDocument.Source.Length];
-                    codeDocument.Source.CopyTo(0, chars, 0, chars.Length);
-                    return new string(chars);
-                }
-            }
-
-            return null;
-        }
-
-        private static DiagnosticMessage GetDiagnosticMessage(Diagnostic diagnostic)
-        {
-            var mappedLineSpan = diagnostic.Location.GetMappedLineSpan();
-            return new DiagnosticMessage(
-                diagnostic.GetMessage(),
-                CSharpDiagnosticFormatter.Instance.Format(diagnostic),
-                mappedLineSpan.Path,
-                mappedLineSpan.StartLinePosition.Line + 1,
-                mappedLineSpan.StartLinePosition.Character + 1,
-                mappedLineSpan.EndLinePosition.Line + 1,
-                mappedLineSpan.EndLinePosition.Character + 1);
-        }
-    }
-}

src/Microsoft.AspNetCore.Mvc.Razor/Internal/ICompilerCache.cs

@@ -1,25 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using System;
-using Microsoft.AspNetCore.Mvc.Razor.Compilation;
-
-namespace Microsoft.AspNetCore.Mvc.Razor.Internal
-{
-    /// <summary>
-    /// Caches the result of runtime compilation of Razor files for the duration of the app lifetime.
-    /// </summary>
-    public interface ICompilerCache
-    {
-        /// <summary>
-        /// Get an existing compilation result, or create and add a new one if it is
-        /// not available in the cache or is expired.
-        /// </summary>
-        /// <param name="relativePath">Application relative path to the file.</param>
-        /// <param name="compile">An delegate that will generate a compilation result.</param>
-        /// <returns>A cached <see cref="CompilationResult"/>.</returns>
-        CompilerCacheResult GetOrAdd(
-            string relativePath,
-            Func<string, CompilerCacheContext> compile);
-    }
-}

src/Microsoft.AspNetCore.Mvc.Razor/Internal/ICompilerCacheProvider.cs

@@ -1,16 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-namespace Microsoft.AspNetCore.Mvc.Razor.Internal
-{
-    /// <summary>
-    /// Provides access to a cached <see cref="ICompilerCache"/> instance.
-    /// </summary>
-    public interface ICompilerCacheProvider
-    {
-        /// <summary>
-        /// The cached <see cref="ICompilerCache"/> instance.
-        /// </summary>
-        ICompilerCache Cache { get; }
-    }
-}

src/Microsoft.AspNetCore.Mvc.Razor/Internal/RazorCompiler.cs

@@ -1,133 +0,0 @@
-
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using Microsoft.AspNetCore.Diagnostics;
-using Microsoft.AspNetCore.Mvc.Razor.Compilation;
-using Microsoft.AspNetCore.Razor.Language;
-using Microsoft.AspNetCore.Mvc.Razor.Extensions;
-
-namespace Microsoft.AspNetCore.Mvc.Razor.Internal
-{
-    public class RazorCompiler
-    {
-        private readonly ICompilationService _compilationService;
-        private readonly ICompilerCacheProvider _compilerCacheProvider;
-        private readonly RazorTemplateEngine _templateEngine;
-        private readonly Func<string, CompilerCacheContext> _getCacheContext;
-        private readonly Func<CompilerCacheContext, CompilationResult> _getCompilationResultDelegate;
-
-        public RazorCompiler(
-            ICompilationService compilationService,
-            ICompilerCacheProvider compilerCacheProvider,
-            RazorTemplateEngine templateEngine)
-        {
-            _compilationService = compilationService;
-            _compilerCacheProvider = compilerCacheProvider;
-            _templateEngine = templateEngine;
-            _getCacheContext = GetCacheContext;
-            _getCompilationResultDelegate = GetCompilationResult;
-        }
-
-        private ICompilerCache CompilerCache => _compilerCacheProvider.Cache;
-
-        public CompilerCacheResult Compile(string relativePath)
-        {
-            return CompilerCache.GetOrAdd(relativePath, _getCacheContext);
-        }
-
-        private CompilerCacheContext GetCacheContext(string path)
-        {
-            var item = _templateEngine.Project.GetItem(path);
-            var imports = _templateEngine.Project.FindHierarchicalItems(path, _templateEngine.Options.ImportsFileName);
-            return new CompilerCacheContext(item, imports, GetCompilationResult);
-        }
-
-        private CompilationResult GetCompilationResult(CompilerCacheContext cacheContext)
-        {
-            var projectItem = cacheContext.ProjectItem;
-            var codeDocument = _templateEngine.CreateCodeDocument(projectItem.Path);
-            var cSharpDocument = _templateEngine.GenerateCode(codeDocument);
-
-            CompilationResult compilationResult;
-            if (cSharpDocument.Diagnostics.Count > 0)
-            {
-                compilationResult = GetCompilationFailedResult(
-                    codeDocument,
-                    cSharpDocument.Diagnostics);
-            }
-            else
-            {
-                compilationResult = _compilationService.Compile(codeDocument, cSharpDocument);
-            }
-
-            return compilationResult;
-        }
-
-        internal CompilationResult GetCompilationFailedResult(
-            RazorCodeDocument codeDocument,
-            IEnumerable<RazorDiagnostic> diagnostics)
-        {
-            // If a SourceLocation does not specify a file path, assume it is produced from parsing the current file.
-            var messageGroups = diagnostics.GroupBy(
-                razorError => razorError.Span.FilePath ?? codeDocument.Source.FileName,
-                StringComparer.Ordinal);
-
-            var failures = new List<CompilationFailure>();
-            foreach (var group in messageGroups)
-            {
-                var filePath = group.Key;
-                var fileContent = ReadContent(codeDocument, filePath);
-                var compilationFailure = new CompilationFailure(
-                    filePath,
-                    fileContent,
-                    compiledContent: string.Empty,
-                    messages: group.Select(parserError => CreateDiagnosticMessage(parserError, filePath)));
-                failures.Add(compilationFailure);
-            }
-
-            return new CompilationResult(failures);
-        }
-
-        private static string ReadContent(RazorCodeDocument codeDocument, string filePath)
-        {
-            RazorSourceDocument sourceDocument = null;
-            if (string.IsNullOrEmpty(filePath) || string.Equals(codeDocument.Source.FileName, filePath, StringComparison.Ordinal))
-            {
-                sourceDocument = codeDocument.Source;
-            }
-            else
-            {
-                sourceDocument = codeDocument.Imports.FirstOrDefault(f => string.Equals(f.FileName, filePath, StringComparison.Ordinal));
-            }
-
-            if (sourceDocument != null)
-            {
-                var contentChars = new char[sourceDocument.Length];
-                sourceDocument.CopyTo(0, contentChars, 0, sourceDocument.Length);
-                return new string(contentChars);
-            }
-
-            return string.Empty;
-        }
-
-        private static DiagnosticMessage CreateDiagnosticMessage(
-            RazorDiagnostic razorDiagnostic,
-            string filePath)
-        {
-            var sourceSpan = razorDiagnostic.Span;
-            var message = razorDiagnostic.GetMessage();
-            return new DiagnosticMessage(
-                message: message,
-                formattedMessage: razorDiagnostic.ToString(),
-                filePath: filePath,
-                startLine: sourceSpan.LineIndex + 1,
-                startColumn: sourceSpan.CharacterIndex,
-                endLine: sourceSpan.LineIndex + 1,
-                endColumn: sourceSpan.CharacterIndex + sourceSpan.Length);
-        }
-    }
-}

src/Microsoft.AspNetCore.Mvc.Razor/Internal/RazorViewCompiler.cs

@@ -0,0 +1,267 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System;
+using System.Collections.Concurrent;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.IO;
+using System.Linq;
+using System.Reflection;
+using System.Text;
+using System.Threading.Tasks;
+using Microsoft.AspNetCore.Mvc.Razor.Compilation;
+using Microsoft.AspNetCore.Razor.Language;
+using Microsoft.CodeAnalysis.CSharp;
+using Microsoft.CodeAnalysis.Text;
+using Microsoft.Extensions.Caching.Memory;
+using Microsoft.Extensions.FileProviders;
+using Microsoft.Extensions.Logging;
+
+namespace Microsoft.AspNetCore.Mvc.Razor.Internal
+{
+    /// <summary>
+    /// Caches the result of runtime compilation of Razor files for the duration of the application lifetime.
+    /// </summary>
+    public class RazorViewCompiler : IViewCompiler
+    {
+        private readonly object _initializeLock = new object();
+        private readonly object _cacheLock = new object();
+        private readonly ConcurrentDictionary<string, string> _normalizedPathLookup;
+        private readonly IFileProvider _fileProvider;
+        private readonly RazorTemplateEngine _templateEngine;
+        private readonly Action<RoslynCompilationContext> _compilationCallback;
+        private readonly ILogger _logger;
+        private readonly CSharpCompiler _csharpCompiler;
+        private IMemoryCache _cache;
+
+        public RazorViewCompiler(
+            IFileProvider fileProvider,
+            RazorTemplateEngine templateEngine,
+            CSharpCompiler csharpCompiler,
+            Action<RoslynCompilationContext> compilationCallback,
+            IList<CompiledViewDescriptor> precompiledViews,
+            ILogger logger)
+        {
+            if (fileProvider == null)
+            {
+                throw new ArgumentNullException(nameof(fileProvider));
+            }
+
+            if (templateEngine == null)
+            {
+                throw new ArgumentNullException(nameof(templateEngine));
+            }
+
+            if (csharpCompiler == null)
+            {
+                throw new ArgumentNullException(nameof(csharpCompiler));
+            }
+
+            if (compilationCallback == null)
+            {
+                throw new ArgumentNullException(nameof(compilationCallback));
+            }
+
+            if (precompiledViews == null)
+            {
+                throw new ArgumentNullException(nameof(precompiledViews));
+            }
+
+            if (logger == null)
+            {
+                throw new ArgumentNullException(nameof(logger));
+            }
+
+            _fileProvider = fileProvider;
+            _templateEngine = templateEngine;
+            _csharpCompiler = csharpCompiler;
+            _compilationCallback = compilationCallback;
+            _logger = logger;
+
+            _normalizedPathLookup = new ConcurrentDictionary<string, string>(StringComparer.Ordinal);
+            _cache = new MemoryCache(new MemoryCacheOptions());
+
+            foreach (var precompiledView in precompiledViews)
+            {
+                _cache.Set(
+                    precompiledView.RelativePath,
+                    Task.FromResult(precompiledView),
+                    new MemoryCacheEntryOptions { Priority = CacheItemPriority.NeverRemove });
+            }
+        }
+
+        /// <inheritdoc />
+        public Task<CompiledViewDescriptor> CompileAsync(string relativePath)
+        {
+            if (relativePath == null)
+            {
+                throw new ArgumentNullException(nameof(relativePath));
+            }
+
+            // Attempt to lookup the cache entry using the passed in path. This will succeed if the path is already
+            // normalized and a cache entry exists.
+            if (!_cache.TryGetValue(relativePath, out Task<CompiledViewDescriptor> cachedResult))
+            {
+                var normalizedPath = GetNormalizedPath(relativePath);
+                if (!_cache.TryGetValue(normalizedPath, out cachedResult))
+                {
+                    cachedResult = CreateCacheEntry(normalizedPath);
+                }
+            }
+
+            return cachedResult;
+        }
+
+        private Task<CompiledViewDescriptor> CreateCacheEntry(string normalizedPath)
+        {
+            TaskCompletionSource<CompiledViewDescriptor> compilationTaskSource = null;
+            MemoryCacheEntryOptions cacheEntryOptions;
+            Task<CompiledViewDescriptor> cacheEntry;
+
+            // Safe races cannot be allowed when compiling Razor pages. To ensure only one compilation request succeeds
+            // per file, we'll lock the creation of a cache entry. Creating the cache entry should be very quick. The
+            // actual work for compiling files happens outside the critical section.
+            lock (_cacheLock)
+            {
+                if (_cache.TryGetValue(normalizedPath, out cacheEntry))
+                {
+                    return cacheEntry;
+                }
+
+                cacheEntryOptions = new MemoryCacheEntryOptions();
+
+                cacheEntryOptions.ExpirationTokens.Add(_fileProvider.Watch(normalizedPath));
+                var projectItem = _templateEngine.Project.GetItem(normalizedPath);
+                if (!projectItem.Exists)
+                {
+                    cacheEntry = Task.FromResult(new CompiledViewDescriptor
+                    {
+                        RelativePath = normalizedPath,
+                        ExpirationTokens = cacheEntryOptions.ExpirationTokens,
+                    });
+                }
+                else
+                {
+                    // A file exists and needs to be compiled.
+                    compilationTaskSource = new TaskCompletionSource<CompiledViewDescriptor>();
+                    foreach (var importItem in _templateEngine.GetImportItems(projectItem))
+                    {
+                        cacheEntryOptions.ExpirationTokens.Add(_fileProvider.Watch(importItem.Path));
+                    }
+                    cacheEntry = compilationTaskSource.Task;
+                }
+
+                cacheEntry = _cache.Set(normalizedPath, cacheEntry, cacheEntryOptions);
+            }
+
+            if (compilationTaskSource != null)
+            {
+                // Indicates that a file was found and needs to be compiled.
+                Debug.Assert(cacheEntryOptions != null);
+
+                try
+                {
+                    var descriptor = CompileAndEmit(normalizedPath);
+                    descriptor.ExpirationTokens = cacheEntryOptions.ExpirationTokens;
+                    compilationTaskSource.SetResult(descriptor);
+                }
+                catch (Exception ex)
+                {
+                    compilationTaskSource.SetException(ex);
+                }
+            }
+
+            return cacheEntry;
+        }
+
+        protected virtual CompiledViewDescriptor CompileAndEmit(string relativePath)
+        {
+            var codeDocument = _templateEngine.CreateCodeDocument(relativePath);
+            var cSharpDocument = _templateEngine.GenerateCode(codeDocument);
+
+            if (cSharpDocument.Diagnostics.Count > 0)
+            {
+                throw CompilationFailedExceptionFactory.Create(
+                    codeDocument,
+                    cSharpDocument.Diagnostics);
+            }
+
+            var generatedAssembly = CompileAndEmit(codeDocument, cSharpDocument.GeneratedCode);
+            var exportedType = generatedAssembly.GetExportedTypes().FirstOrDefault(f => !f.IsNested);
+            return new CompiledViewDescriptor
+            {
+                ViewAttribute = new RazorViewAttribute(relativePath, exportedType),
+                RelativePath = relativePath,
+            };
+        }
+
+        internal Assembly CompileAndEmit(RazorCodeDocument codeDocument, string generatedCode)
+        {
+            _logger.GeneratedCodeToAssemblyCompilationStart(codeDocument.Source.FileName);
+
+            var startTimestamp = _logger.IsEnabled(LogLevel.Debug) ? Stopwatch.GetTimestamp() : 0;
+
+            var assemblyName = Path.GetRandomFileName();
+            var compilation = CreateCompilation(generatedCode, assemblyName);
+
+            using (var assemblyStream = new MemoryStream())
+            using (var pdbStream = new MemoryStream())
+            {
+                var result = compilation.Emit(
+                    assemblyStream,
+                    pdbStream,
+                    options: _csharpCompiler.EmitOptions);
+
+                if (!result.Success)
+                {
+                    throw CompilationFailedExceptionFactory.Create(
+                        codeDocument,
+                        generatedCode,
+                        assemblyName,
+                        result.Diagnostics);
+                }
+
+                assemblyStream.Seek(0, SeekOrigin.Begin);
+                pdbStream.Seek(0, SeekOrigin.Begin);
+
+                var assembly = Assembly.Load(assemblyStream.ToArray(), pdbStream.ToArray());
+                _logger.GeneratedCodeToAssemblyCompilationEnd(codeDocument.Source.FileName, startTimestamp);
+
+                return assembly;
+            }
+        }
+
+        private CSharpCompilation CreateCompilation(string compilationContent, string assemblyName)
+        {
+            var sourceText = SourceText.From(compilationContent, Encoding.UTF8);
+            var syntaxTree = _csharpCompiler.CreateSyntaxTree(sourceText).WithFilePath(assemblyName);
+            var compilation = _csharpCompiler
+                .CreateCompilation(assemblyName)
+                .AddSyntaxTrees(syntaxTree);
+            compilation = ExpressionRewriter.Rewrite(compilation);
+
+            var compilationContext = new RoslynCompilationContext(compilation);
+            _compilationCallback(compilationContext);
+            compilation = compilationContext.Compilation;
+            return compilation;
+        }
+
+        private string GetNormalizedPath(string relativePath)
+        {
+            Debug.Assert(relativePath != null);
+            if (relativePath.Length == 0)
+            {
+                return relativePath;
+            }
+
+            if (!_normalizedPathLookup.TryGetValue(relativePath, out var normalizedPath))
+            {
+                normalizedPath = ViewPath.NormalizePath(relativePath);
+                _normalizedPathLookup[relativePath] = normalizedPath;
+            }
+
+            return normalizedPath;
+        }
+    }
+}

src/Microsoft.AspNetCore.Mvc.Razor/Internal/RazorViewCompilerProvider.cs

@@ -0,0 +1,80 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System;
+using System.Threading;
+using Microsoft.AspNetCore.Mvc.ApplicationParts;
+using Microsoft.AspNetCore.Mvc.Razor.Compilation;
+using Microsoft.AspNetCore.Razor.Language;
+using Microsoft.Extensions.FileProviders;
+using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.Options;
+
+namespace Microsoft.AspNetCore.Mvc.Razor.Internal
+{
+    public class RazorViewCompilerProvider : IViewCompilerProvider
+    {
+        private readonly RazorTemplateEngine _razorTemplateEngine;
+        private readonly ApplicationPartManager _applicationPartManager;
+        private readonly IRazorViewEngineFileProviderAccessor _fileProviderAccessor;
+        private readonly CSharpCompiler _csharpCompiler;
+        private readonly RazorViewEngineOptions _viewEngineOptions;
+        private readonly ILogger<RazorViewCompiler> _logger;
+        private readonly Func<IViewCompiler> _createCompiler;
+
+        private object _initializeLock = new object();
+        private bool _initialized;
+        private IViewCompiler _compiler;
+
+        public RazorViewCompilerProvider(
+            ApplicationPartManager applicationPartManager,
+            RazorTemplateEngine razorTemplateEngine,
+            IRazorViewEngineFileProviderAccessor fileProviderAccessor,
+            CSharpCompiler csharpCompiler,
+            IOptions<RazorViewEngineOptions> viewEngineOptionsAccessor,
+            ILoggerFactory loggerFactory)
+        {
+            _applicationPartManager = applicationPartManager;
+            _razorTemplateEngine = razorTemplateEngine;
+            _fileProviderAccessor = fileProviderAccessor;
+            _csharpCompiler = csharpCompiler;
+            _viewEngineOptions = viewEngineOptionsAccessor.Value;
+
+            _logger = loggerFactory.CreateLogger<RazorViewCompiler>();
+            _createCompiler = CreateCompiler;
+        }
+
+        public IViewCompiler GetCompiler()
+        {
+            var fileProvider = _fileProviderAccessor.FileProvider;
+            if (fileProvider is NullFileProvider)
+            {
+                var message = Resources.FormatFileProvidersAreRequired(
+                    typeof(RazorViewEngineOptions).FullName,
+                    nameof(RazorViewEngineOptions.FileProviders),
+                    typeof(IFileProvider).FullName);
+                throw new InvalidOperationException(message);
+            }
+
+            return LazyInitializer.EnsureInitialized(
+                ref _compiler,
+                ref _initialized,
+                ref _initializeLock,
+                _createCompiler);
+        }
+
+        private IViewCompiler CreateCompiler()
+        {
+            var feature = new ViewsFeature();
+            _applicationPartManager.PopulateFeature(feature);
+
+            return new RazorViewCompiler(
+                _fileProviderAccessor.FileProvider,
+                _razorTemplateEngine,
+                _csharpCompiler,
+                _viewEngineOptions.CompilationCallback,
+                feature.ViewDescriptors,
+                _logger);
+        }
+    }
+}

src/Microsoft.AspNetCore.Mvc.Razor/Internal/ViewPath.cs

@@ -0,0 +1,45 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using Microsoft.Extensions.Primitives;
+
+namespace Microsoft.AspNetCore.Mvc.Razor.Internal
+{
+    public static class ViewPath
+    {
+        public static string NormalizePath(string path)
+        {
+            var addLeadingSlash = path[0] != '\\' && path[0] != '/';
+            var transformSlashes = path.IndexOf('\\') != -1;
+
+            if (!addLeadingSlash && !transformSlashes)
+            {
+                return path;
+            }
+
+            var length = path.Length;
+            if (addLeadingSlash)
+            {
+                length++;
+            }
+
+            var builder = new InplaceStringBuilder(length);
+            if (addLeadingSlash)
+            {
+                builder.Append('/');
+            }
+
+            for (var i = 0; i < path.Length; i++)
+            {
+                var ch = path[i];
+                if (ch == '\\')
+                {
+                    ch = '/';
+                }
+                builder.Append(ch);
+            }
+
+            return builder.ToString();
+        }
+    }
+}

src/Microsoft.AspNetCore.Mvc.RazorPages/ApplicationParts/CompiledPageFeature.cs

@@ -1,12 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using System.Collections.Generic;
-
-namespace Microsoft.AspNetCore.Mvc.ApplicationParts
-{
-    public class CompiledPageInfoFeature
-    {
-        public IList<CompiledPageInfo> CompiledPages { get; } = new List<CompiledPageInfo>();
-    }
-}

src/Microsoft.AspNetCore.Mvc.RazorPages/ApplicationParts/CompiledPageFeatureProvider.cs

@@ -5,7 +5,9 @@ using System;
 using System.Collections.Generic;
 using System.Linq;
 using Microsoft.AspNetCore.Mvc.Razor.Compilation;
+using Microsoft.AspNetCore.Mvc.Razor.Internal;
 using Microsoft.AspNetCore.Mvc.RazorPages.Infrastructure;
+using Microsoft.Extensions.Primitives;
 
 namespace Microsoft.AspNetCore.Mvc.ApplicationParts
 {
@@ -30,24 +32,45 @@ namespace Microsoft.AspNetCore.Mvc.ApplicationParts
         /// <inheritdoc />
         public void PopulateFeature(IEnumerable<ApplicationPart> parts, ViewsFeature feature)
         {
-            foreach (var item in GetCompiledPageInfo(parts))
+            foreach (var item in GetCompiledPageDescriptors(parts))
             {
-                feature.Views.Add(item.Path, item.CompiledType);
+                feature.ViewDescriptors.Add(item);
             }
         }
 
         /// <summary>
-        /// Gets the sequence of <see cref="CompiledPageInfo"/> from <paramref name="parts"/>.
+        /// Gets the sequence of <see cref="CompiledViewDescriptor"/> from <paramref name="parts"/>.
         /// </summary>
         /// <param name="parts">The <see cref="ApplicationPart"/>s</param>
-        /// <returns>The sequence of <see cref="CompiledPageInfo"/>.</returns>
+        /// <returns>The sequence of <see cref="CompiledViewDescriptor"/>.</returns>
-        public static IEnumerable<CompiledPageInfo> GetCompiledPageInfo(IEnumerable<ApplicationPart> parts)
+        public static IEnumerable<CompiledViewDescriptor> GetCompiledPageDescriptors(IEnumerable<ApplicationPart> parts)
         {
-            return parts.OfType<AssemblyPart>()
+            var manifests = parts.OfType<AssemblyPart>()
                 .Select(part => CompiledViewManfiest.GetManifestType(part, FullyQualifiedManifestTypeName))
                 .Where(type => type != null)
-                .Select(type => (CompiledPageManifest)Activator.CreateInstance(type))
+                .Select(type => (CompiledPageManifest)Activator.CreateInstance(type));
-                .SelectMany(manifest => manifest.CompiledPages);
+
+            foreach (var page in manifests.SelectMany(m => m.CompiledPages))
+            {
+                var normalizedPath = ViewPath.NormalizePath(page.Path);
+                var modelType = page.CompiledType.GetProperty("Model")?.PropertyType;
+
+                var pageAttribute = new RazorPageAttribute(
+                    normalizedPath,
+                    page.CompiledType,
+                    modelType,
+                    page.RoutePrefix);
+
+                var viewDescriptor = new CompiledViewDescriptor
+                {
+                    RelativePath = normalizedPath,
+                    ViewAttribute = pageAttribute,
+                    ExpirationTokens = Array.Empty<IChangeToken>(),
+                    IsPrecompiled = true,
+                };
+
+                yield return viewDescriptor;
+            }
         }
     }
 }

src/Microsoft.AspNetCore.Mvc.RazorPages/Infrastructure/RazorPageAttribute.cs

@@ -0,0 +1,22 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System;
+using Microsoft.AspNetCore.Mvc.Razor.Compilation;
+
+namespace Microsoft.AspNetCore.Mvc.RazorPages.Infrastructure
+{
+    public class RazorPageAttribute : RazorViewAttribute
+    {
+        public RazorPageAttribute(string path, Type viewType, Type modelType, string routeTemplate)
+            : base(path, viewType)
+        {
+            ModelType = modelType;
+            RouteTemplate = routeTemplate;
+        }
+
+        public Type ModelType { get; }
+
+        public string RouteTemplate { get; }
+    }
+}

src/Microsoft.AspNetCore.Mvc.RazorPages/Internal/CompiledPageApplicationModelProvider.cs

@@ -5,6 +5,8 @@ using System;
 using System.Collections.Generic;
 using Microsoft.AspNetCore.Mvc.ApplicationModels;
 using Microsoft.AspNetCore.Mvc.ApplicationParts;
+using Microsoft.AspNetCore.Mvc.Razor.Compilation;
+using Microsoft.AspNetCore.Mvc.RazorPages.Infrastructure;
 using Microsoft.Extensions.Options;
 
 namespace Microsoft.AspNetCore.Mvc.RazorPages.Internal
@@ -56,17 +58,18 @@ namespace Microsoft.AspNetCore.Mvc.RazorPages.Internal
                 }
 
                 var cachedApplicationModels = new List<PageApplicationModel>();
-                var pages = GetCompiledPages();
+                foreach (var pageDescriptor in GetCompiledPageDescriptors())
-                foreach (var page in pages)
                 {
-                    if (!page.Path.StartsWith(rootDirectory))
+                    var pageAttribute = (RazorPageAttribute)pageDescriptor.ViewAttribute;
+
+                    if (!pageDescriptor.RelativePath.StartsWith(rootDirectory))
                     {
                         continue;
                     }
 
-                    var viewEnginePath = GetViewEnginePath(rootDirectory, page.Path);
+                    var viewEnginePath = GetViewEnginePath(rootDirectory, pageDescriptor.RelativePath);
-                    var model = new PageApplicationModel(page.Path, viewEnginePath);
+                    var model = new PageApplicationModel(pageDescriptor.RelativePath, viewEnginePath);
-                    PageSelectorModel.PopulateDefaults(model, page.RoutePrefix);
+                    PageSelectorModel.PopulateDefaults(model, pageAttribute.RouteTemplate);
 
                     cachedApplicationModels.Add(model);
                 }
@@ -75,8 +78,8 @@ namespace Microsoft.AspNetCore.Mvc.RazorPages.Internal
             }
         }
 
-        protected virtual IEnumerable<CompiledPageInfo> GetCompiledPages()
+        protected virtual IEnumerable<CompiledViewDescriptor> GetCompiledPageDescriptors()
-            => CompiledPageFeatureProvider.GetCompiledPageInfo(_applicationManager.ApplicationParts);
+            => CompiledPageFeatureProvider.GetCompiledPageDescriptors(_applicationManager.ApplicationParts);
 
         private string GetViewEnginePath(string rootDirectory, string path)
         {

src/Microsoft.AspNetCore.Mvc.RazorPages/Internal/DefaultPageLoader.cs

@@ -5,7 +5,7 @@ using System;
 using System.Collections.Generic;
 using System.Reflection;
 using Microsoft.AspNetCore.Mvc.ModelBinding;
-using Microsoft.AspNetCore.Mvc.Razor.Internal;
+using Microsoft.AspNetCore.Mvc.Razor.Compilation;
 using Microsoft.AspNetCore.Mvc.RazorPages.Infrastructure;
 using Microsoft.Extensions.Internal;
 
@@ -14,28 +14,42 @@ namespace Microsoft.AspNetCore.Mvc.RazorPages.Internal
     public class DefaultPageLoader : IPageLoader
     {
         private const string ModelPropertyName = "Model";
-        
-        private readonly RazorCompiler _compiler;
 
-        public DefaultPageLoader(RazorCompiler compiler)
+        private readonly IViewCompilerProvider _viewCompilerProvider;
+
+        public DefaultPageLoader(IViewCompilerProvider viewCompilerProvider)
         {
-            _compiler = compiler;
+            _viewCompilerProvider = viewCompilerProvider;
         }
 
+        private IViewCompiler Compiler => _viewCompilerProvider.GetCompiler();
+
         public CompiledPageActionDescriptor Load(PageActionDescriptor actionDescriptor)
         {
-            var result = _compiler.Compile(actionDescriptor.RelativePath);
+            var compileTask = Compiler.CompileAsync(actionDescriptor.RelativePath);
-            return CreateDescriptor(actionDescriptor, result.CompiledType.GetTypeInfo());
+            var viewDescriptor = compileTask.GetAwaiter().GetResult();
+            var viewAttribute = viewDescriptor.ViewAttribute;
+
+            // Pages always have a model type. If it's not set explicitly by the developer using
+            // @model, it will be the same as the page type.
+            var modelType = viewAttribute.ViewType.GetProperty(ModelPropertyName)?.PropertyType;
+
+            var pageAttribute = new RazorPageAttribute(
+                viewAttribute.Path,
+                viewAttribute.ViewType,
+                modelType,
+                routeTemplate: null);
+
+            return CreateDescriptor(actionDescriptor, pageAttribute);
         }
 
         // Internal for unit testing
-        internal static CompiledPageActionDescriptor CreateDescriptor(PageActionDescriptor actionDescriptor, TypeInfo pageType)
+        internal static CompiledPageActionDescriptor CreateDescriptor(
+            PageActionDescriptor actionDescriptor,
+            RazorPageAttribute pageAttribute)
         {
-            // Pages always have a model type. If it's not set explicitly by the developer using
+            var pageType = pageAttribute.ViewType.GetTypeInfo();
-            // @model, it will be the same as the page type.
+            var modelType = pageAttribute.ModelType?.GetTypeInfo();
-            //
-            // However, we allow it to be null here for ease of testing.
-            var modelType = pageType.GetProperty(ModelPropertyName)?.PropertyType.GetTypeInfo();
 
             // Now we want to find the handler methods. If the model defines any handlers, then we'll use those,
             // otherwise look at the page itself (unless the page IS the model, in which case we already looked).

test/Microsoft.AspNetCore.Mvc.Razor.Test/Compilation/CompilationResultTest.cs

@@ -1,32 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using System.Linq;
-using Microsoft.AspNetCore.Diagnostics;
-using Xunit;
-
-namespace Microsoft.AspNetCore.Mvc.Razor.Compilation
-{
-    public class CompilationResultTest
-    {
-        [Fact]
-        public void EnsureSuccessful_ThrowsIfCompilationFailed()
-        {
-            // Arrange
-            var compilationFailure = new CompilationFailure(
-                "test",
-                sourceFileContent: string.Empty,
-                compiledContent: string.Empty,
-                messages: Enumerable.Empty<AspNetCore.Diagnostics.DiagnosticMessage>());
-            var failures = new[] { compilationFailure };
-            var result = new CompilationResult(failures);
-
-            // Act and Assert
-            Assert.Null(result.CompiledType);
-            Assert.Same(failures, result.CompilationFailures);
-            var exception = Assert.Throws<CompilationFailedException>(() => result.EnsureSuccessful());
-            var failure = Assert.Single(exception.CompilationFailures);
-            Assert.Same(compilationFailure, failure);
-        }
-    }
-}

test/Microsoft.AspNetCore.Mvc.Razor.Test/Compilation/ViewsFeatureProviderTest.cs

@@ -27,7 +27,7 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Compilation
             applicationPartManager.PopulateFeature(feature);
 
             // Assert
-            Assert.Empty(feature.Views);
+            Assert.Empty(feature.ViewDescriptors);
         }
 
         [Fact]
@@ -52,21 +52,21 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Compilation
             applicationPartManager.PopulateFeature(feature);
 
             // Assert
-            Assert.Collection(feature.Views.OrderBy(f => f.Key, StringComparer.Ordinal),
+            Assert.Collection(feature.ViewDescriptors.OrderBy(f => f.RelativePath, StringComparer.Ordinal),
                 view =>
                 {
-                    Assert.Equal("/Areas/Admin/Views/About.cshtml", view.Key);
+                    Assert.Equal("/Areas/Admin/Views/About.cshtml", view.RelativePath);
-                    Assert.Equal(typeof(int), view.Value);
+                    Assert.Equal(typeof(int), view.ViewAttribute.ViewType);
                 },
                 view =>
                 {
-                    Assert.Equal("/Areas/Admin/Views/Index.cshtml", view.Key);
+                    Assert.Equal("/Areas/Admin/Views/Index.cshtml", view.RelativePath);
-                    Assert.Equal(typeof(string), view.Value);
+                    Assert.Equal(typeof(string), view.ViewAttribute.ViewType);
                 },
                 view =>
                 {
-                    Assert.Equal("/Views/test/Index.cshtml", view.Key);
+                    Assert.Equal("/Views/test/Index.cshtml", view.RelativePath);
-                    Assert.Equal(typeof(object), view.Value);
+                    Assert.Equal(typeof(object), view.ViewAttribute.ViewType);
                 });
         }
 
@@ -87,7 +87,7 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Compilation
             applicationPartManager.PopulateFeature(feature);
 
             // Assert
-            Assert.Empty(feature.Views);
+            Assert.Empty(feature.ViewDescriptors);
         }
 
         [Fact]
@@ -104,7 +104,7 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Compilation
             applicationPartManager.PopulateFeature(feature);
 
             // Assert
-            Assert.Empty(feature.Views);
+            Assert.Empty(feature.ViewDescriptors);
         }
 
         private class TestableViewsFeatureProvider : ViewsFeatureProvider

test/Microsoft.AspNetCore.Mvc.Razor.Test/Internal/CSharpCompilerTest.cs

@@ -0,0 +1,43 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System.Reflection;
+using Microsoft.AspNetCore.Mvc.ApplicationParts;
+using Microsoft.AspNetCore.Mvc.Razor.Compilation;
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.Text;
+using Xunit;
+
+namespace Microsoft.AspNetCore.Mvc.Razor.Internal
+{
+    public class CSharpCompilerTest
+    {
+        [Fact]
+        public void Compile_UsesApplicationsCompilationSettings_ForParsingAndCompilation()
+        {
+            // Arrange
+            var content = "public class Test {}";
+            var define = "MY_CUSTOM_DEFINE";
+            var options = new TestOptionsManager<RazorViewEngineOptions>();
+            options.Value.ParseOptions = options.Value.ParseOptions.WithPreprocessorSymbols(define);
+            var razorReferenceManager = new RazorReferenceManager(GetApplicationPartManager(), options);
+            var compiler = new CSharpCompiler(razorReferenceManager, options);
+
+            // Act
+            var syntaxTree = compiler.CreateSyntaxTree(SourceText.From(content));
+
+            // Assert
+            Assert.Contains(define, syntaxTree.Options.PreprocessorSymbolNames);
+        }
+
+        private static ApplicationPartManager GetApplicationPartManager()
+        {
+            var applicationPartManager = new ApplicationPartManager();
+            var assembly = typeof(CSharpCompilerTest).GetTypeInfo().Assembly;
+            applicationPartManager.ApplicationParts.Add(new AssemblyPart(assembly));
+            applicationPartManager.FeatureProviders.Add(new MetadataReferenceFeatureProvider());
+
+            return applicationPartManager;
+        }
+    }
+}

test/Microsoft.AspNetCore.Mvc.Razor.Test/Internal/CompilerCacheTest.cs

@@ -1,656 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Threading;
-using System.Threading.Tasks;
-using Microsoft.AspNetCore.Diagnostics;
-using Microsoft.AspNetCore.Mvc.Razor.Compilation;
-using Microsoft.AspNetCore.Razor.Language;
-using Microsoft.Extensions.FileProviders;
-using Moq;
-using Xunit;
-
-namespace Microsoft.AspNetCore.Mvc.Razor.Internal
-{
-    public class CompilerCacheTest
-    {
-        private const string ViewPath = "/Views/Home/Index.cshtml";
-        private const string PrecompiledViewsPath = "/Views/Home/Precompiled.cshtml";
-        private static readonly string[] _viewImportsPath = new[]
-        {
-            "/Views/Home/_ViewImports.cshtml",
-            "/Views/_ViewImports.cshtml",
-            "/_ViewImports.cshtml",
-        };
-        private readonly IDictionary<string, Type> _precompiledViews = new Dictionary<string, Type>
-        {
-            { PrecompiledViewsPath, typeof(PreCompile) }
-        };
-
-        public static TheoryData ViewImportsPaths
-        {
-            get
-            {
-                var theoryData = new TheoryData<string>();
-                foreach (var path in _viewImportsPath)
-                {
-                    theoryData.Add(path);
-                }
-
-                return theoryData;
-            }
-        }
-
-        [Fact]
-        public void GetOrAdd_ReturnsFileNotFoundResult_IfFileIsNotFoundInFileSystem()
-        {
-            // Arrange
-            var item = new Mock<RazorProjectItem>();
-            item
-                .SetupGet(i => i.Path)
-                .Returns("/some/path");
-            item
-                .SetupGet(i => i.Exists)
-                .Returns(false);
-
-            var fileProvider = new TestFileProvider();
-            var cache = new CompilerCache(fileProvider);
-            var compilerCacheContext = new CompilerCacheContext(
-                item.Object,
-                Enumerable.Empty<RazorProjectItem>(),
-                _ => throw new Exception("Shouldn't be called."));
-
-            // Act
-            var result = cache.GetOrAdd("/some/path", _ => compilerCacheContext);
-
-            // Assert
-            Assert.False(result.Success);
-        }
-
-        [Fact]
-        public void GetOrAdd_ReturnsCompilationResultFromFactory()
-        {
-            // Arrange
-            var fileProvider = new TestFileProvider();
-            fileProvider.AddFile(ViewPath, "some content");
-            var cache = new CompilerCache(fileProvider);
-            var expected = new CompilationResult(typeof(TestView));
-
-            // Act
-            var result = cache.GetOrAdd(ViewPath, CreateContextFactory(expected));
-
-            // Assert
-            Assert.True(result.Success);
-            Assert.Equal(typeof(TestView), result.CompiledType);
-            Assert.Equal(ViewPath, result.RelativePath);
-        }
-
-        [Theory]
-        [InlineData("/Areas/Finances/Views/Home/Index.cshtml")]
-        [InlineData(@"Areas\Finances\Views\Home\Index.cshtml")]
-        [InlineData(@"\Areas\Finances\Views\Home\Index.cshtml")]
-        [InlineData(@"\Areas\Finances\Views/Home\Index.cshtml")]
-        public void GetOrAdd_NormalizesPathSepartorForPaths(string relativePath)
-        {
-            // Arrange
-            var viewPath = "/Areas/Finances/Views/Home/Index.cshtml";
-            var fileProvider = new TestFileProvider();
-            fileProvider.AddFile(viewPath, "some content");
-            var cache = new CompilerCache(fileProvider);
-            var expected = new CompilationResult(typeof(TestView));
-
-            // Act - 1
-            var result1 = cache.GetOrAdd(@"Areas\Finances\Views\Home\Index.cshtml", CreateContextFactory(expected));
-
-            // Assert - 1
-            Assert.Equal(typeof(TestView), result1.CompiledType);
-
-            // Act - 2
-            var result2 = cache.GetOrAdd(relativePath, ThrowsIfCalled);
-
-            // Assert - 2
-            Assert.Equal(typeof(TestView), result2.CompiledType);
-        }
-
-        [Fact]
-        public void GetOrAdd_ReturnsFailedCompilationResult_IfFileWasRemovedFromFileSystem()
-        {
-            // Arrange
-            var fileProvider = new TestFileProvider();
-            var fileInfo = fileProvider.AddFile(ViewPath, "some content");
-
-            var foundItem = new FileProviderRazorProjectItem(fileInfo, "", ViewPath);
-
-            var notFoundItem = new Mock<RazorProjectItem>();
-            notFoundItem
-                .SetupGet(i => i.Path)
-                .Returns(ViewPath);
-            notFoundItem
-                .SetupGet(i => i.Exists)
-                .Returns(false);
-
-            var cache = new CompilerCache(fileProvider);
-            var expected = new CompilationResult(typeof(TestView));
-            var cacheContext = new CompilerCacheContext(foundItem, Enumerable.Empty<RazorProjectItem>(), _ => expected);
-
-            // Act 1
-            var result1 = cache.GetOrAdd(ViewPath, _ => cacheContext);
-
-            // Assert 1
-            Assert.True(result1.Success);
-            Assert.Equal(typeof(TestView), result1.CompiledType);
-
-            // Act 2
-            // Delete the file from the file system and set it's expiration token.
-            cacheContext = new CompilerCacheContext(
-                notFoundItem.Object,
-                Enumerable.Empty<RazorProjectItem>(),
-                _ => throw new Exception("Shouldn't be called."));
-            fileProvider.GetChangeToken(ViewPath).HasChanged = true;
-            var result2 = cache.GetOrAdd(ViewPath, _ => cacheContext);
-
-            // Assert 2
-            Assert.False(result2.Success);
-        }
-
-        [Fact]
-        public void GetOrAdd_ReturnsNewResultIfFileWasModified()
-        {
-            // Arrange
-            var fileProvider = new TestFileProvider();
-            fileProvider.AddFile(ViewPath, "some content");
-            var cache = new CompilerCache(fileProvider);
-            var expected1 = new CompilationResult(typeof(TestView));
-            var expected2 = new CompilationResult(typeof(DifferentView));
-
-            // Act 1
-            var result1 = cache.GetOrAdd(ViewPath, CreateContextFactory(expected1));
-
-            // Assert 1
-            Assert.True(result1.Success);
-            Assert.Equal(typeof(TestView), result1.CompiledType);
-
-            // Act 2
-            // Verify we're getting cached results.
-            var result2 = cache.GetOrAdd(ViewPath, ThrowsIfCalled);
-
-            // Assert 2
-            Assert.True(result2.Success);
-            Assert.Equal(typeof(TestView), result1.CompiledType);
-
-            // Act 3
-            fileProvider.GetChangeToken(ViewPath).HasChanged = true;
-            var result3 = cache.GetOrAdd(ViewPath, CreateContextFactory(expected2));
-
-            // Assert 3
-            Assert.True(result3.Success);
-            Assert.Equal(typeof(DifferentView), result3.CompiledType);
-        }
-
-        [Theory]
-        [MemberData(nameof(ViewImportsPaths))]
-        public void GetOrAdd_ReturnsNewResult_IfAncestorViewImportsWereModified(string globalImportPath)
-        {
-            // Arrange
-            var fileProvider = new TestFileProvider();
-            fileProvider.AddFile(ViewPath, "some content");
-            var cache = new CompilerCache(fileProvider);
-            var expected1 = new CompilationResult(typeof(TestView));
-            var expected2 = new CompilationResult(typeof(DifferentView));
-
-            // Act 1
-            var result1 = cache.GetOrAdd(ViewPath, CreateContextFactory(expected1));
-
-            // Assert 1
-            Assert.True(result1.Success);
-            Assert.Equal(typeof(TestView), result1.CompiledType);
-
-            // Act 2
-            // Verify we're getting cached results.
-            var result2 = cache.GetOrAdd(ViewPath, ThrowsIfCalled);
-
-            // Assert 2
-            Assert.True(result2.Success);
-            Assert.Equal(typeof(TestView), result1.CompiledType);
-
-            // Act 3
-            fileProvider.GetChangeToken(globalImportPath).HasChanged = true;
-            var result3 = cache.GetOrAdd(ViewPath, CreateContextFactory(expected2));
-
-            // Assert 2
-            Assert.True(result3.Success);
-            Assert.Equal(typeof(DifferentView), result3.CompiledType);
-        }
-
-        [Fact]
-        public void GetOrAdd_DoesNotQueryFileSystem_IfCachedFileTriggerWasNotSet()
-        {
-            // Arrange
-            var mockFileProvider = new Mock<TestFileProvider> { CallBase = true };
-            var fileProvider = mockFileProvider.Object;
-            fileProvider.AddFile(ViewPath, "some content");
-            var cache = new CompilerCache(fileProvider);
-            var expected = new CompilationResult(typeof(TestView));
-
-            // Act 1
-            var result1 = cache.GetOrAdd(ViewPath, CreateContextFactory(expected));
-
-            // Assert 1
-            Assert.True(result1.Success);
-            Assert.Equal(typeof(TestView), result1.CompiledType);
-
-            // Act 2
-            var result2 = cache.GetOrAdd(ViewPath, ThrowsIfCalled);
-
-            // Assert 2
-            Assert.True(result2.Success);
-        }
-
-        [Fact]
-        public void GetOrAdd_UsesViewsSpecifiedFromRazorFileInfoCollection()
-        {
-            // Arrange
-            var fileProvider = new TestFileProvider();
-            var cache = new CompilerCache(fileProvider, _precompiledViews);
-
-            // Act
-            var result = cache.GetOrAdd(PrecompiledViewsPath, ThrowsIfCalled);
-
-            // Assert
-            Assert.True(result.Success);
-            Assert.Equal(typeof(PreCompile), result.CompiledType);
-            Assert.Same(PrecompiledViewsPath, result.RelativePath);
-        }
-
-        [Fact]
-        public void GetOrAdd_DoesNotRecompile_IfFileTriggerWasSetForPrecompiledFile()
-        {
-            // Arrange
-            var fileProvider = new TestFileProvider();
-            var cache = new CompilerCache(fileProvider, _precompiledViews);
-
-            // Act
-            fileProvider.Watch(PrecompiledViewsPath);
-            fileProvider.GetChangeToken(PrecompiledViewsPath).HasChanged = true;
-            var result = cache.GetOrAdd(PrecompiledViewsPath, ThrowsIfCalled);
-
-            // Assert
-            Assert.True(result.Success);
-            Assert.True(result.IsPrecompiled);
-            Assert.Equal(typeof(PreCompile), result.CompiledType);
-        }
-
-        [Theory]
-        [MemberData(nameof(ViewImportsPaths))]
-        public void GetOrAdd_DoesNotRecompile_IfFileTriggerWasSetForViewImports(string globalImportPath)
-        {
-            // Arrange
-            var fileProvider = new TestFileProvider();
-            var cache = new CompilerCache(fileProvider, _precompiledViews);
-
-            // Act
-            fileProvider.Watch(globalImportPath);
-            fileProvider.GetChangeToken(globalImportPath).HasChanged = true;
-            var result = cache.GetOrAdd(PrecompiledViewsPath, ThrowsIfCalled);
-
-            // Assert
-            Assert.True(result.Success);
-            Assert.Equal(typeof(PreCompile), result.CompiledType);
-        }
-
-        [Fact]
-        public void GetOrAdd_ReturnsRuntimeCompiled()
-        {
-            // Arrange
-            var fileProvider = new TestFileProvider();
-            fileProvider.AddFile(ViewPath, "some content");
-            var cache = new CompilerCache(fileProvider, _precompiledViews);
-            var expected = new CompilationResult(typeof(TestView));
-
-            // Act 1
-            var result1 = cache.GetOrAdd(ViewPath, CreateContextFactory(expected));
-
-            // Assert 1
-            Assert.Equal(typeof(TestView), result1.CompiledType);
-
-            // Act 2
-            var result2 = cache.GetOrAdd(ViewPath, ThrowsIfCalled);
-
-            // Assert 2
-            Assert.True(result2.Success);
-            Assert.Equal(typeof(TestView), result2.CompiledType);
-        }
-
-        [Fact]
-        public void GetOrAdd_ReturnsPrecompiledViews()
-        {
-            // Arrange
-            var fileProvider = new TestFileProvider();
-            var cache = new CompilerCache(fileProvider, _precompiledViews);
-            var expected = new CompilationResult(typeof(TestView));
-
-            // Act
-            var result1 = cache.GetOrAdd(PrecompiledViewsPath, ThrowsIfCalled);
-
-            // Assert
-            Assert.Equal(typeof(PreCompile), result1.CompiledType);
-        }
-
-        [Theory]
-        [InlineData("/Areas/Finances/Views/Home/Index.cshtml")]
-        [InlineData(@"Areas\Finances\Views\Home\Index.cshtml")]
-        [InlineData(@"\Areas\Finances\Views\Home\Index.cshtml")]
-        [InlineData(@"\Areas\Finances\Views/Home\Index.cshtml")]
-        public void GetOrAdd_NormalizesPathSepartorForPathsThatArePrecompiled(string relativePath)
-        {
-            // Arrange
-            var expected = typeof(PreCompile);
-            var viewPath = "/Areas/Finances/Views/Home/Index.cshtml";
-            var cache = new CompilerCache(
-                new TestFileProvider(),
-                new Dictionary<string, Type>
-                {
-                    { viewPath, expected }
-                });
-
-            // Act
-            var result = cache.GetOrAdd(relativePath, ThrowsIfCalled);
-
-            // Assert
-            Assert.Equal(typeof(PreCompile), result.CompiledType);
-            Assert.Equal(viewPath, result.RelativePath);
-        }
-
-        [Theory]
-        [InlineData(@"Areas\Finances\Views\Home\Index.cshtml")]
-        [InlineData(@"\Areas\Finances\Views\Home\Index.cshtml")]
-        [InlineData(@"\Areas\Finances\Views/Home\Index.cshtml")]
-        public void ConstructorNormalizesPrecompiledViewPath(string viewPath)
-        {
-            // Arrange
-            var expected = typeof(PreCompile);
-            var cache = new CompilerCache(
-                new TestFileProvider(),
-                new Dictionary<string, Type>
-                {
-                    { viewPath, expected }
-                });
-
-            // Act
-            var result = cache.GetOrAdd("/Areas/Finances/Views/Home/Index.cshtml", ThrowsIfCalled);
-
-            // Assert
-            Assert.Equal(typeof(PreCompile), result.CompiledType);
-        }
-
-        [Fact]
-        public async Task GetOrAdd_AllowsConcurrentCompilationOfMultipleRazorPages()
-        {
-            // Arrange
-            var waitDuration = TimeSpan.FromSeconds(20);
-            var fileProvider = new TestFileProvider();
-            fileProvider.AddFile("/Views/Home/Index.cshtml", "Index content");
-            fileProvider.AddFile("/Views/Home/About.cshtml", "About content");
-            var resetEvent1 = new AutoResetEvent(initialState: false);
-            var resetEvent2 = new ManualResetEvent(initialState: false);
-            var cache = new CompilerCache(fileProvider);
-            var compilingOne = false;
-            var compilingTwo = false;
-
-            Func<CompilerCacheContext, CompilationResult> compile1 = _ =>
-            {
-                compilingOne = true;
-
-                // Event 2
-                Assert.True(resetEvent1.WaitOne(waitDuration));
-
-                // Event 3
-                Assert.True(resetEvent2.Set());
-
-                // Event 6
-                Assert.True(resetEvent1.WaitOne(waitDuration));
-
-                Assert.True(compilingTwo);
-                return new CompilationResult(typeof(TestView));
-            };
-
-            Func<CompilerCacheContext, CompilationResult> compile2 = _ =>
-            {
-                compilingTwo = true;
-
-                // Event 4
-                Assert.True(resetEvent2.WaitOne(waitDuration));
-
-                // Event 5
-                Assert.True(resetEvent1.Set());
-
-                Assert.True(compilingOne);
-                return new CompilationResult(typeof(DifferentView));
-            };
-
-
-            // Act
-            var task1 = Task.Run(() =>
-            {
-                return cache.GetOrAdd("/Views/Home/Index.cshtml", path =>
-                {
-                    var projectItem = new FileProviderRazorProjectItem(new TestFileInfo(), "", path);
-                    return new CompilerCacheContext(projectItem, Enumerable.Empty<RazorProjectItem>(), compile1);
-                });
-            });
-
-            var task2 = Task.Run(() =>
-            {
-                // Event 4
-                return cache.GetOrAdd("/Views/Home/About.cshtml", path =>
-                {
-                    var projectItem = new FileProviderRazorProjectItem(new TestFileInfo(), "", path);
-                    return new CompilerCacheContext(projectItem, Enumerable.Empty<RazorProjectItem>(), compile2);
-                });
-            });
-
-            // Event 1
-            resetEvent1.Set();
-
-            await Task.WhenAll(task1, task2);
-
-            // Assert
-            var result1 = task1.Result;
-            var result2 = task2.Result;
-            Assert.True(compilingOne);
-            Assert.True(compilingTwo);
-        }
-
-        [Fact]
-        public async Task GetOrAdd_DoesNotCreateMultipleCompilationResults_ForConcurrentInvocations()
-        {
-            // Arrange
-            var waitDuration = TimeSpan.FromSeconds(20);
-            var fileProvider = new TestFileProvider();
-            fileProvider.AddFile(ViewPath, "some content");
-            var resetEvent1 = new ManualResetEvent(initialState: false);
-            var resetEvent2 = new ManualResetEvent(initialState: false);
-            var cache = new CompilerCache(fileProvider);
-
-            Func<CompilerCacheContext, CompilationResult> compile = _ =>
-            {
-                // Event 2
-                resetEvent1.WaitOne(waitDuration);
-
-                // Event 3
-                resetEvent2.Set();
-                return new CompilationResult(typeof(TestView));
-            };
-
-            // Act
-            var task1 = Task.Run(() =>
-            {
-                return cache.GetOrAdd(ViewPath, path =>
-                {
-                    var projectItem = new FileProviderRazorProjectItem(new TestFileInfo(), "", path);
-                    return new CompilerCacheContext(projectItem, Enumerable.Empty<RazorProjectItem>(), compile);
-                });
-            });
-
-            var task2 = Task.Run(() =>
-            {
-                // Event 4
-                Assert.True(resetEvent2.WaitOne(waitDuration));
-                return cache.GetOrAdd(ViewPath, ThrowsIfCalled);
-            });
-
-            // Event 1
-            resetEvent1.Set();
-            await Task.WhenAll(task1, task2);
-
-            // Assert
-            var result1 = task1.Result;
-            var result2 = task2.Result;
-            Assert.Same(result1.CompiledType, result2.CompiledType);
-        }
-
-        [Fact]
-        public void GetOrAdd_ThrowsIfNullFileProvider()
-        {
-            // Arrange
-            var expected =
-                $"'{typeof(RazorViewEngineOptions).FullName}.{nameof(RazorViewEngineOptions.FileProviders)}' must " +
-                $"not be empty. At least one '{typeof(IFileProvider).FullName}' is required to locate a view for " +
-                "rendering.";
-            var fileProvider = new NullFileProvider();
-            var cache = new CompilerCache(fileProvider);
-
-            // Act & Assert
-            var exception = Assert.Throws<InvalidOperationException>(
-                () => cache.GetOrAdd(ViewPath, _ => { throw new InvalidTimeZoneException(); }));
-            Assert.Equal(expected, exception.Message);
-        }
-
-        [Fact]
-        public void GetOrAdd_CachesCompilationExceptions()
-        {
-            // Arrange
-            var fileProvider = new TestFileProvider();
-            fileProvider.AddFile(ViewPath, "some content");
-            var cache = new CompilerCache(fileProvider);
-            var exception = new InvalidTimeZoneException();
-
-            // Act and Assert - 1
-            var actual = Assert.Throws<InvalidTimeZoneException>(() =>
-                cache.GetOrAdd(ViewPath, _ => ThrowsIfCalled(ViewPath, exception)));
-            Assert.Same(exception, actual);
-
-            // Act and Assert - 2
-            actual = Assert.Throws<InvalidTimeZoneException>(() => cache.GetOrAdd(ViewPath, ThrowsIfCalled));
-            Assert.Same(exception, actual);
-        }
-
-        [Fact]
-        public void GetOrAdd_ReturnsSuccessfulCompilationResultIfTriggerExpires()
-        {
-            // Arrange
-            var fileProvider = new TestFileProvider();
-            fileProvider.AddFile(ViewPath, "some content");
-            var changeToken = fileProvider.AddChangeToken(ViewPath);
-            var cache = new CompilerCache(fileProvider);
-
-            // Act and Assert - 1
-            Assert.Throws<InvalidTimeZoneException>(() =>
-                cache.GetOrAdd(ViewPath, _ => { throw new InvalidTimeZoneException(); }));
-
-            // Act - 2
-            changeToken.HasChanged = true;
-            var result = cache.GetOrAdd(ViewPath, CreateContextFactory(new CompilationResult(typeof(TestView))));
-
-            // Assert - 2
-            Assert.Same(typeof(TestView), result.CompiledType);
-        }
-
-        [Fact]
-        public void GetOrAdd_CachesExceptionsInCompilationResult()
-        {
-            // Arrange
-            var fileProvider = new TestFileProvider();
-            fileProvider.AddFile(ViewPath, "some content");
-            var cache = new CompilerCache(fileProvider);
-            var diagnosticMessages = new[]
-            {
-                new DiagnosticMessage("message", "message", ViewPath, 1, 1, 1, 1)
-            };
-            var compilationResult = new CompilationResult(new[]
-            {
-                new CompilationFailure(ViewPath, "some content", "compiled content", diagnosticMessages)
-            });
-            var context = CreateContextFactory(compilationResult);
-
-            // Act and Assert - 1
-            var ex = Assert.Throws<CompilationFailedException>(() => cache.GetOrAdd(ViewPath, context));
-            Assert.Same(compilationResult.CompilationFailures, ex.CompilationFailures);
-
-            // Act and Assert - 2
-            ex = Assert.Throws<CompilationFailedException>(() => cache.GetOrAdd(ViewPath, ThrowsIfCalled));
-            Assert.Same(compilationResult.CompilationFailures, ex.CompilationFailures);
-        }
-
-        private class TestView : RazorPage
-        {
-            public override Task ExecuteAsync()
-            {
-                throw new NotImplementedException();
-            }
-        }
-
-        private class PreCompile : RazorPage
-        {
-            public override Task ExecuteAsync()
-            {
-                throw new NotImplementedException();
-            }
-        }
-
-        public class DifferentView : RazorPage
-        {
-            public override Task ExecuteAsync()
-            {
-                throw new NotImplementedException();
-            }
-        }
-
-        private CompilerCacheContext ThrowsIfCalled(string path) =>
-            ThrowsIfCalled(path, new Exception("Shouldn't be called"));
-
-        private CompilerCacheContext ThrowsIfCalled(string path, Exception exception)
-        {
-            exception = exception ?? new Exception("Shouldn't be called");
-            var projectItem = new FileProviderRazorProjectItem(new TestFileInfo(), "", path);
-
-            return new CompilerCacheContext(
-                projectItem,
-                Enumerable.Empty<RazorProjectItem>(),
-                 _ => throw exception);
-        }
-
-        private Func<string, CompilerCacheContext> CreateContextFactory(CompilationResult compile)
-        {
-            return path => CreateCacheContext(compile, path);
-        }
-
-        private CompilerCacheContext CreateCacheContext(CompilationResult compile, string path = ViewPath)
-        {
-            var projectItem = new FileProviderRazorProjectItem(new TestFileInfo(), "", path);
-
-            var imports = new List<RazorProjectItem>();
-            foreach (var importFilePath in _viewImportsPath)
-            {
-                var importProjectItem = new FileProviderRazorProjectItem(new TestFileInfo(), "", importFilePath);
-
-                imports.Add(importProjectItem);
-            }
-
-            return new CompilerCacheContext(projectItem, imports, _ => compile);
-        }
-    }
-}

test/Microsoft.AspNetCore.Mvc.Razor.Test/Internal/CompilerFailedExceptionFactoryTest.cs

@@ -3,15 +3,15 @@
 
 using System.IO;
 using System.Text;
-using Microsoft.AspNetCore.Mvc.Razor.Compilation;
 using Microsoft.AspNetCore.Mvc.Razor.Extensions;
 using Microsoft.AspNetCore.Razor.Language;
-using Moq;
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.Text;
 using Xunit;
 
 namespace Microsoft.AspNetCore.Mvc.Razor.Internal
 {
-    public class RazorCompilerTest
+    public class CompilerFailedExceptionFactoryTest
     {
         [Fact]
         public void GetCompilationFailedResult_ReadsRazorErrorsFromPage()
@@ -24,15 +24,11 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Internal
             var razorProject = new FileProviderRazorProject(fileProvider);
 
             var templateEngine = new MvcRazorTemplateEngine(razorEngine, razorProject);
-            var compiler = new RazorCompiler(
-                Mock.Of<ICompilationService>(),
-                GetCompilerCacheProvider(fileProvider),
-                templateEngine);
             var codeDocument = templateEngine.CreateCodeDocument(viewPath);
 
             // Act
             var csharpDocument = templateEngine.GenerateCode(codeDocument);
-            var compilationResult = compiler.GetCompilationFailedResult(codeDocument, csharpDocument.Diagnostics);
+            var compilationResult = CompilationFailedExceptionFactory.Create(codeDocument, csharpDocument.Diagnostics);
 
             // Assert
             var failure = Assert.Single(compilationResult.CompilationFailures);
@@ -59,15 +55,11 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Internal
             var razorProject = new FileProviderRazorProject(fileProvider);
 
             var templateEngine = new MvcRazorTemplateEngine(razorEngine, razorProject);
-            var compiler = new RazorCompiler(
-                Mock.Of<ICompilationService>(),
-                GetCompilerCacheProvider(fileProvider),
-                templateEngine);
             var codeDocument = templateEngine.CreateCodeDocument(viewPath);
 
             // Act
             var csharpDocument = templateEngine.GenerateCode(codeDocument);
-            var compilationResult = compiler.GetCompilationFailedResult(codeDocument, csharpDocument.Diagnostics);
+            var compilationResult = CompilationFailedExceptionFactory.Create(codeDocument, csharpDocument.Diagnostics);
 
             // Assert
             var failure = Assert.Single(compilationResult.CompilationFailures);
@@ -93,15 +85,11 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Internal
             var razorProject = new FileProviderRazorProject(fileProvider);
 
             var templateEngine = new MvcRazorTemplateEngine(razorEngine, razorProject);
-            var compiler = new RazorCompiler(
-                Mock.Of<ICompilationService>(),
-                GetCompilerCacheProvider(fileProvider),
-                templateEngine);
             var codeDocument = templateEngine.CreateCodeDocument(viewPath);
 
             // Act
             var csharpDocument = templateEngine.GenerateCode(codeDocument);
-            var compilationResult = compiler.GetCompilationFailedResult(codeDocument, csharpDocument.Diagnostics);
+            var compilationResult = CompilationFailedExceptionFactory.Create(codeDocument, csharpDocument.Diagnostics);
 
             // Assert
             var failure = Assert.Single(compilationResult.CompilationFailures);
@@ -131,15 +119,11 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Internal
                     ImportsFileName = "_MyImports.cshtml",
                 }
             };
-            var compiler = new RazorCompiler(
-                Mock.Of<ICompilationService>(),
-                GetCompilerCacheProvider(fileProvider),
-                templateEngine);
             var codeDocument = templateEngine.CreateCodeDocument(viewPath);
 
             // Act
             var csharpDocument = templateEngine.GenerateCode(codeDocument);
-            var compilationResult = compiler.GetCompilationFailedResult(codeDocument, csharpDocument.Diagnostics);
+            var compilationResult = CompilationFailedExceptionFactory.Create(codeDocument, csharpDocument.Diagnostics);
 
             // Assert
             Assert.Collection(
@@ -183,13 +167,9 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Internal
                 GetRazorDiagnostic("message-4", new SourceLocation(viewImportsPath, 1, 3, 8), length: 4),
             };
             var fileProvider = new TestFileProvider();
-            var compiler = new RazorCompiler(
-                Mock.Of<ICompilationService>(),
-                GetCompilerCacheProvider(fileProvider),
-                new MvcRazorTemplateEngine(RazorEngine.Create(), new FileProviderRazorProject(fileProvider)));
 
             // Act
-            var result = compiler.GetCompilationFailedResult(codeDocument, diagnostics);
+            var result = CompilationFailedExceptionFactory.Create(codeDocument, diagnostics);
 
             // Assert
             Assert.Collection(result.CompilationFailures,
@@ -243,13 +223,85 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Internal
             });
         }
 
-        private ICompilerCacheProvider GetCompilerCacheProvider(TestFileProvider fileProvider)
+        [Fact]
+        public void GetCompilationFailedResult_ReturnsCompilationResult_WithGroupedMessages()
         {
-            var compilerCache = new CompilerCache(fileProvider);
+            // Arrange
-            var compilerCacheProvider = new Mock<ICompilerCacheProvider>();
+            var viewPath = "Views/Home/Index";
-            compilerCacheProvider.SetupGet(p => p.Cache).Returns(compilerCache);
+            var generatedCodeFileName = "Generated Code";
+            var codeDocument = RazorCodeDocument.Create(RazorSourceDocument.Create("view-content", viewPath));
+            var assemblyName = "random-assembly-name";
 
-            return compilerCacheProvider.Object;
+            var diagnostics = new[]
+            {
+                Diagnostic.Create(
+                    GetRoslynDiagnostic("message-1"),
+                    Location.Create(
+                        viewPath,
+                        new TextSpan(10, 5),
+                        new LinePositionSpan(new LinePosition(10, 1), new LinePosition(10, 2)))),
+                Diagnostic.Create(
+                    GetRoslynDiagnostic("message-2"),
+                    Location.Create(
+                        assemblyName,
+                        new TextSpan(1, 6),
+                        new LinePositionSpan(new LinePosition(1, 2), new LinePosition(3, 4)))),
+                Diagnostic.Create(
+                    GetRoslynDiagnostic("message-3"),
+                    Location.Create(
+                        viewPath,
+                        new TextSpan(40, 50),
+                        new LinePositionSpan(new LinePosition(30, 5), new LinePosition(40, 12)))),
+            };
+
+            // Act
+            var compilationResult = CompilationFailedExceptionFactory.Create(
+                codeDocument,
+                "compilation-content",
+                assemblyName,
+                diagnostics);
+
+            // Assert
+            Assert.Collection(compilationResult.CompilationFailures,
+                failure =>
+                {
+                    Assert.Equal(viewPath, failure.SourceFilePath);
+                    Assert.Equal("view-content", failure.SourceFileContent);
+                    Assert.Collection(failure.Messages,
+                        message =>
+                        {
+                            Assert.Equal("message-1", message.Message);
+                            Assert.Equal(viewPath, message.SourceFilePath);
+                            Assert.Equal(11, message.StartLine);
+                            Assert.Equal(2, message.StartColumn);
+                            Assert.Equal(11, message.EndLine);
+                            Assert.Equal(3, message.EndColumn);
+                        },
+                        message =>
+                        {
+                            Assert.Equal("message-3", message.Message);
+                            Assert.Equal(viewPath, message.SourceFilePath);
+                            Assert.Equal(31, message.StartLine);
+                            Assert.Equal(6, message.StartColumn);
+                            Assert.Equal(41, message.EndLine);
+                            Assert.Equal(13, message.EndColumn);
+                        });
+                },
+                failure =>
+                {
+                    Assert.Equal(generatedCodeFileName, failure.SourceFilePath);
+                    Assert.Equal("compilation-content", failure.SourceFileContent);
+                    Assert.Collection(failure.Messages,
+                        message =>
+                        {
+                            Assert.Equal("message-2", message.Message);
+                            Assert.Equal(assemblyName, message.SourceFilePath);
+                            Assert.Equal(2, message.StartLine);
+                            Assert.Equal(3, message.StartColumn);
+                            Assert.Equal(4, message.EndLine);
+                            Assert.Equal(5, message.EndColumn);
+                        });
+                });
         }
 
         private static RazorSourceDocument Create(string path, string template)
@@ -265,5 +317,16 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Internal
 
             return RazorDiagnostic.Create(diagnosticDescriptor, sourceSpan);
         }
+
+        private static DiagnosticDescriptor GetRoslynDiagnostic(string messageFormat)
+        {
+            return new DiagnosticDescriptor(
+                id: "someid",
+                title: "sometitle",
+                messageFormat: messageFormat,
+                category: "some-category",
+                defaultSeverity: DiagnosticSeverity.Error,
+                isEnabledByDefault: true);
+        }
     }
 }

test/Microsoft.AspNetCore.Mvc.Razor.Test/Internal/DefaultRazorPageFactoryProviderTest.cs

@@ -4,8 +4,6 @@
 using System;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Mvc.Razor.Compilation;
-using Microsoft.AspNetCore.Mvc.Razor.Extensions;
-using Microsoft.AspNetCore.Razor.Language;
 using Microsoft.Extensions.Primitives;
 using Moq;
 using Xunit;
@@ -24,12 +22,17 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Internal
                 Mock.Of<IChangeToken>(),
                 Mock.Of<IChangeToken>(),
             };
-            var compilerCache = new Mock<ICompilerCache>();
+            var descriptor = new CompiledViewDescriptor
+            {
+                RelativePath = path,
+                ExpirationTokens = expirationTokens,
+            };
+            var compilerCache = new Mock<IViewCompiler>();
             compilerCache
-                .Setup(f => f.GetOrAdd(It.IsAny<string>(), It.IsAny<Func<string, CompilerCacheContext>>()))
+                .Setup(f => f.CompileAsync(It.IsAny<string>()))
-                .Returns(new CompilerCacheResult(path, expirationTokens));
+                .ReturnsAsync(descriptor);
 
-            var factoryProvider = new DefaultRazorPageFactoryProvider(CreateCompiler(compilerCache.Object));
+            var factoryProvider = new DefaultRazorPageFactoryProvider(GetCompilerProvider(compilerCache.Object));
 
             // Act
             var result = factoryProvider.CreateFactory(path);
@@ -49,19 +52,25 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Internal
                 Mock.Of<IChangeToken>(),
                 Mock.Of<IChangeToken>(),
             };
-            var compilerCache = new Mock<ICompilerCache>();
+            var descriptor = new CompiledViewDescriptor
+            {
+                RelativePath = relativePath,
+                ViewAttribute = new RazorViewAttribute(relativePath, typeof(TestRazorPage)),
+                ExpirationTokens = expirationTokens,
+            };
+            var compilerCache = new Mock<IViewCompiler>();
             compilerCache
-                .Setup(f => f.GetOrAdd(It.IsAny<string>(), It.IsAny<Func<string, CompilerCacheContext>>()))
+                .Setup(f => f.CompileAsync(It.IsAny<string>()))
-                .Returns(new CompilerCacheResult(relativePath, new CompilationResult(typeof(TestRazorPage)), expirationTokens));
+                .ReturnsAsync(descriptor);
 
-            var factoryProvider = new DefaultRazorPageFactoryProvider(CreateCompiler(compilerCache.Object));
+            var factoryProvider = new DefaultRazorPageFactoryProvider(GetCompilerProvider(compilerCache.Object));
 
             // Act
             var result = factoryProvider.CreateFactory(relativePath);
 
             // Assert
             Assert.True(result.Success);
-            Assert.Equal(expirationTokens, result.ExpirationTokens);
+            Assert.Equal(expirationTokens, descriptor.ExpirationTokens);
         }
 
         [Fact]
@@ -69,12 +78,18 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Internal
         {
             // Arrange
             var relativePath = "/file-exists";
-            var compilerCache = new Mock<ICompilerCache>();
+            var descriptor = new CompiledViewDescriptor
-            compilerCache
+            {
-                .Setup(f => f.GetOrAdd(It.IsAny<string>(), It.IsAny<Func<string, CompilerCacheContext>>()))
+                RelativePath = relativePath,
-                .Returns(new CompilerCacheResult(relativePath, new CompilationResult(typeof(TestRazorPage)), new IChangeToken[0]));
+                ViewAttribute = new RazorViewAttribute(relativePath, typeof(TestRazorPage)),
-            
+                ExpirationTokens = Array.Empty<IChangeToken>(),
-            var factoryProvider = new DefaultRazorPageFactoryProvider(CreateCompiler(compilerCache.Object));
+            };
+            var viewCompiler = new Mock<IViewCompiler>();
+            viewCompiler
+                .Setup(f => f.CompileAsync(It.IsAny<string>()))
+                .ReturnsAsync(descriptor);
+
+            var factoryProvider = new DefaultRazorPageFactoryProvider(GetCompilerProvider(viewCompiler.Object));
 
             // Act
             var result = factoryProvider.CreateFactory(relativePath);
@@ -85,17 +100,14 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Internal
             Assert.Equal("/file-exists", actual.Path);
         }
 
-        private RazorCompiler CreateCompiler(ICompilerCache cache)
+        private IViewCompilerProvider GetCompilerProvider(IViewCompiler cache)
         {
-            var compilerCacheProvider = new Mock<ICompilerCacheProvider>();
+            var compilerCacheProvider = new Mock<IViewCompilerProvider>();
             compilerCacheProvider
-                .SetupGet(c => c.Cache)
+                .Setup(c => c.GetCompiler())
                 .Returns(cache);
 
-            return new RazorCompiler(
+            return compilerCacheProvider.Object;
-                Mock.Of<ICompilationService>(),
-                compilerCacheProvider.Object,
-                new MvcRazorTemplateEngine(RazorEngine.Create(), new FileProviderRazorProject(new TestFileProvider())));
         }
 
         private class TestRazorPage : RazorPage

test/Microsoft.AspNetCore.Mvc.Razor.Test/Internal/DefaultRoslynCompilationServiceTest.cs

@@ -1,350 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using System;
-using System.Reflection;
-using Microsoft.AspNetCore.Mvc.ApplicationParts;
-using Microsoft.AspNetCore.Mvc.Razor.Compilation;
-using Microsoft.AspNetCore.Razor.Language;
-using Microsoft.CodeAnalysis;
-using Microsoft.CodeAnalysis.Text;
-using Microsoft.Extensions.Logging.Abstractions;
-using Microsoft.Extensions.Options;
-using Moq;
-using Xunit;
-
-namespace Microsoft.AspNetCore.Mvc.Razor.Internal
-{
-    public class DefaultRoslynCompilationServiceTest
-    {
-        [Fact]
-        public void Compile_SucceedsForCSharp7()
-        {
-            // Arrange
-            var content = @"
-public class MyTestType
-{
-    private string _name;
-
-    public string Name
-    {
-        get => _name;
-        set => _name = value ?? throw new System.ArgumentNullException(nameof(value));
-    }
-}";
-            var compilationService = GetRoslynCompilationService();
-
-            var codeDocument = RazorCodeDocument.Create(RazorSourceDocument.Create("Hello world", "test.cshtml"));
-
-            var csharpDocument = RazorCSharpDocument.Create(content, RazorCodeGenerationOptions.CreateDefault(), Array.Empty<RazorDiagnostic>());
-
-            // Act
-            var result = compilationService.Compile(codeDocument, csharpDocument);
-
-            // Assert
-            Assert.Equal("MyTestType", result.CompiledType.Name);
-            Assert.Null(result.CompilationFailures);
-        }
-
-        [Fact]
-        public void Compile_ReturnsCompilationResult()
-        {
-            // Arrange
-            var content = @"
-public class MyTestType  {}";
-
-            var compilationService = GetRoslynCompilationService();
-
-            var codeDocument = RazorCodeDocument.Create(RazorSourceDocument.Create("Hello world", "test.cshtml"));
-
-            var csharpDocument = RazorCSharpDocument.Create(content, RazorCodeGenerationOptions.CreateDefault(), Array.Empty<RazorDiagnostic>());
-
-            // Act
-            var result = compilationService.Compile(codeDocument, csharpDocument);
-
-            // Assert
-            Assert.Equal("MyTestType", result.CompiledType.Name);
-        }
-
-        [Fact]
-        public void Compile_ReturnsCompilationFailureWithPathsFromLinePragmas()
-        {
-            // Arrange
-            var viewPath = "some-relative-path";
-            var fileContent = "test file content";
-            var content = $@"
-#line 1 ""{viewPath}""
-this should fail";
-
-            var compilationService = GetRoslynCompilationService();
-            var codeDocument = RazorCodeDocument.Create(RazorSourceDocument.Create(fileContent, viewPath));
-
-            var csharpDocument = RazorCSharpDocument.Create(content, RazorCodeGenerationOptions.CreateDefault(), Array.Empty<RazorDiagnostic>());
-
-            // Act
-            var result = compilationService.Compile(codeDocument, csharpDocument);
-
-            // Assert
-            Assert.IsType<CompilationResult>(result);
-            Assert.Null(result.CompiledType);
-            var compilationFailure = Assert.Single(result.CompilationFailures);
-            Assert.Equal(viewPath, compilationFailure.SourceFilePath);
-            Assert.Equal(fileContent, compilationFailure.SourceFileContent);
-        }
-
-        [Fact]
-        public void Compile_ReturnsGeneratedCodePath_IfLinePragmaIsNotAvailable()
-        {
-            // Arrange
-            var viewPath = "some-relative-path";
-            var fileContent = "file content";
-            var content = "this should fail";
-
-            var compilationService = GetRoslynCompilationService();
-            var codeDocument = RazorCodeDocument.Create(RazorSourceDocument.Create(fileContent, viewPath));
-
-            var csharpDocument = RazorCSharpDocument.Create(content, RazorCodeGenerationOptions.CreateDefault(), Array.Empty<RazorDiagnostic>());
-
-            // Act
-            var result = compilationService.Compile(codeDocument, csharpDocument);
-
-            // Assert
-            Assert.IsType<CompilationResult>(result);
-            Assert.Null(result.CompiledType);
-
-            var compilationFailure = Assert.Single(result.CompilationFailures);
-            Assert.Equal("Generated Code", compilationFailure.SourceFilePath);
-            Assert.Equal(content, compilationFailure.SourceFileContent);
-        }
-
-        [Fact]
-        public void Compile_UsesApplicationsCompilationSettings_ForParsingAndCompilation()
-        {
-            // Arrange
-            var viewPath = "some-relative-path";
-            var content = @"
-#if MY_CUSTOM_DEFINE
-public class MyCustomDefinedClass {}
-#else
-public class MyNonCustomDefinedClass {}
-#endif
-";
-            var options = GetOptions();
-            options.ParseOptions = options.ParseOptions.WithPreprocessorSymbols("MY_CUSTOM_DEFINE");
-            var compilationService = GetRoslynCompilationService(options: options);
-            var codeDocument = RazorCodeDocument.Create(RazorSourceDocument.Create("Hello world", viewPath));
-
-            var csharpDocument = RazorCSharpDocument.Create(content, RazorCodeGenerationOptions.CreateDefault(), Array.Empty<RazorDiagnostic>());
-
-            // Act
-            var result = compilationService.Compile(codeDocument, csharpDocument);
-
-            // Assert
-            Assert.NotNull(result.CompiledType);
-            Assert.Equal("MyCustomDefinedClass", result.CompiledType.Name);
-        }
-
-        [Fact]
-        public void GetCompilationFailedResult_ReturnsCompilationResult_WithGroupedMessages()
-        {
-            // Arrange
-            var viewPath = "Views/Home/Index";
-            var generatedCodeFileName = "Generated Code";
-            var compilationService = GetRoslynCompilationService();
-            var codeDocument = RazorCodeDocument.Create(RazorSourceDocument.Create("view-content", viewPath));
-            var assemblyName = "random-assembly-name";
-
-            var diagnostics = new[]
-            {
-                Diagnostic.Create(
-                    GetDiagnosticDescriptor("message-1"),
-                    Location.Create(
-                        viewPath,
-                        new TextSpan(10, 5),
-                        new LinePositionSpan(new LinePosition(10, 1), new LinePosition(10, 2)))),
-                Diagnostic.Create(
-                    GetDiagnosticDescriptor("message-2"),
-                    Location.Create(
-                        assemblyName,
-                        new TextSpan(1, 6),
-                        new LinePositionSpan(new LinePosition(1, 2), new LinePosition(3, 4)))),
-                Diagnostic.Create(
-                    GetDiagnosticDescriptor("message-3"),
-                    Location.Create(
-                        viewPath,
-                        new TextSpan(40, 50),
-                        new LinePositionSpan(new LinePosition(30, 5), new LinePosition(40, 12)))),
-            };
-
-            // Act
-            var compilationResult = compilationService.GetCompilationFailedResult(
-                codeDocument,
-                "compilation-content",
-                assemblyName,
-                diagnostics);
-
-            // Assert
-            Assert.Collection(compilationResult.CompilationFailures,
-                failure =>
-                {
-                    Assert.Equal(viewPath, failure.SourceFilePath);
-                    Assert.Equal("view-content", failure.SourceFileContent);
-                    Assert.Collection(failure.Messages,
-                        message =>
-                        {
-                            Assert.Equal("message-1", message.Message);
-                            Assert.Equal(viewPath, message.SourceFilePath);
-                            Assert.Equal(11, message.StartLine);
-                            Assert.Equal(2, message.StartColumn);
-                            Assert.Equal(11, message.EndLine);
-                            Assert.Equal(3, message.EndColumn);
-                        },
-                        message =>
-                        {
-                            Assert.Equal("message-3", message.Message);
-                            Assert.Equal(viewPath, message.SourceFilePath);
-                            Assert.Equal(31, message.StartLine);
-                            Assert.Equal(6, message.StartColumn);
-                            Assert.Equal(41, message.EndLine);
-                            Assert.Equal(13, message.EndColumn);
-                        });
-                },
-                failure =>
-                {
-                    Assert.Equal(generatedCodeFileName, failure.SourceFilePath);
-                    Assert.Equal("compilation-content", failure.SourceFileContent);
-                    Assert.Collection(failure.Messages,
-                        message =>
-                        {
-                            Assert.Equal("message-2", message.Message);
-                            Assert.Equal(assemblyName, message.SourceFilePath);
-                            Assert.Equal(2, message.StartLine);
-                            Assert.Equal(3, message.StartColumn);
-                            Assert.Equal(4, message.EndLine);
-                            Assert.Equal(5, message.EndColumn);
-                        });
-                });
-        }
-
-        [Fact]
-        public void Compile_RunsCallback()
-        {
-            // Arrange
-            var content = "public class MyTestType  {}";
-            RoslynCompilationContext usedCompilation = null;
-            var options = GetOptions(c => usedCompilation = c);
-            var compilationService = GetRoslynCompilationService(options: options);
-
-            var codeDocument = RazorCodeDocument.Create(RazorSourceDocument.Create("Hello world", "some-relative-path"));
-
-            var csharpDocument = RazorCSharpDocument.Create(content, RazorCodeGenerationOptions.CreateDefault(), Array.Empty<RazorDiagnostic>());
-
-            // Act
-            var result = compilationService.Compile(codeDocument, csharpDocument);
-
-            Assert.NotNull(usedCompilation);
-            Assert.Single(usedCompilation.Compilation.SyntaxTrees);
-        }
-
-        [Fact]
-        public void Compile_DoesNotThrowIfReferencesWereClearedInCallback()
-        {
-            // Arrange
-            var options = GetOptions(context =>
-            {
-                context.Compilation = context.Compilation.RemoveAllReferences();
-            });
-            var content = "public class MyTestType  {}";
-            var compilationService = GetRoslynCompilationService(options: options);
-            var codeDocument = RazorCodeDocument.Create(RazorSourceDocument.Create("Hello world", "some-relative-path.cshtml"));
-
-            var csharpDocument = RazorCSharpDocument.Create(content, RazorCodeGenerationOptions.CreateDefault(), Array.Empty<RazorDiagnostic>());
-
-            // Act
-            var result = compilationService.Compile(codeDocument, csharpDocument);
-
-            // Assert
-            Assert.Single(result.CompilationFailures);
-        }
-
-        [Fact]
-        public void Compile_SucceedsIfReferencesAreAddedInCallback()
-        {
-            // Arrange
-            var options = GetOptions(context =>
-            {
-                var assemblyLocation = typeof(object).GetTypeInfo().Assembly.Location;
-
-                context.Compilation = context
-                    .Compilation
-                    .AddReferences(MetadataReference.CreateFromFile(assemblyLocation));
-            });
-            var content = "public class MyTestType  {}";
-            var applicationPartManager = new ApplicationPartManager();
-            var compilationService = GetRoslynCompilationService(applicationPartManager, options);
-
-            var codeDocument = RazorCodeDocument.Create(RazorSourceDocument.Create("Hello world", "some-relative-path.cshtml"));
-
-            var csharpDocument = RazorCSharpDocument.Create(content, RazorCodeGenerationOptions.CreateDefault(), Array.Empty<RazorDiagnostic>());
-
-            // Act
-            var result = compilationService.Compile(codeDocument, csharpDocument);
-
-            // Assert
-            Assert.Null(result.CompilationFailures);
-            Assert.NotNull(result.CompiledType);
-        }
-
-        private static DiagnosticDescriptor GetDiagnosticDescriptor(string messageFormat)
-        {
-            return new DiagnosticDescriptor(
-                id: "someid",
-                title: "sometitle",
-                messageFormat: messageFormat,
-                category: "some-category",
-                defaultSeverity: DiagnosticSeverity.Error,
-                isEnabledByDefault: true);
-        }
-
-        private static RazorViewEngineOptions GetOptions(Action<RoslynCompilationContext> callback = null)
-        {
-            return new RazorViewEngineOptions
-            {
-                CompilationCallback = callback ?? (c => { }),
-            };
-        }
-
-        private static IOptions<RazorViewEngineOptions> GetAccessor(RazorViewEngineOptions options)
-        {
-            var optionsAccessor = new Mock<IOptions<RazorViewEngineOptions>>();
-            optionsAccessor.SetupGet(a => a.Value).Returns(options);
-            return optionsAccessor.Object;
-        }
-
-        private static ApplicationPartManager GetApplicationPartManager()
-        {
-            var applicationPartManager = new ApplicationPartManager();
-            var assembly = typeof(DefaultRoslynCompilationServiceTest).GetTypeInfo().Assembly;
-            applicationPartManager.ApplicationParts.Add(new AssemblyPart(assembly));
-            applicationPartManager.FeatureProviders.Add(new MetadataReferenceFeatureProvider());
-
-            return applicationPartManager;
-        }
-
-        private static DefaultRoslynCompilationService GetRoslynCompilationService(
-            ApplicationPartManager partManager = null,
-            RazorViewEngineOptions options = null)
-        {
-            partManager = partManager ?? GetApplicationPartManager();
-            options = options ?? GetOptions();
-            var optionsAccessor = GetAccessor(options);
-            var referenceManager = new RazorReferenceManager(partManager, optionsAccessor);
-            var compiler = new CSharpCompiler(referenceManager, optionsAccessor);
-
-            return new DefaultRoslynCompilationService(
-                compiler,
-                optionsAccessor,
-                NullLoggerFactory.Instance);
-        }
-    }
-}

test/Microsoft.AspNetCore.Mvc.Razor.Test/Internal/RazorViewCompilerProviderTest.cs

@@ -0,0 +1,44 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System;
+using Microsoft.AspNetCore.Mvc.ApplicationParts;
+using Microsoft.AspNetCore.Razor.Language;
+using Microsoft.Extensions.FileProviders;
+using Microsoft.Extensions.Logging.Abstractions;
+using Moq;
+using Xunit;
+
+namespace Microsoft.AspNetCore.Mvc.Razor.Internal
+{
+    public class RazorViewCompilerProviderTest
+    {
+        [Fact]
+        public void GetCompiler_ThrowsIfNullFileProvider()
+        {
+            // Arrange
+            var expected =
+                $"'{typeof(RazorViewEngineOptions).FullName}.{nameof(RazorViewEngineOptions.FileProviders)}' must " +
+                $"not be empty. At least one '{typeof(IFileProvider).FullName}' is required to locate a view for " +
+                "rendering.";
+            var fileProvider = new NullFileProvider();
+            var accessor = new Mock<IRazorViewEngineFileProviderAccessor>();
+            var applicationManager = new ApplicationPartManager();
+            var options = new TestOptionsManager<RazorViewEngineOptions>();
+            var referenceManager = new RazorReferenceManager(applicationManager, options);
+            accessor.Setup(a => a.FileProvider).Returns(fileProvider);
+            var provider = new RazorViewCompilerProvider(
+                applicationManager,
+                new RazorTemplateEngine(RazorEngine.Create(), new FileProviderRazorProject(fileProvider)),
+                accessor.Object,
+                new CSharpCompiler(referenceManager, options),
+                options,
+                NullLoggerFactory.Instance);
+
+            // Act & Assert
+            var exception = Assert.Throws<InvalidOperationException>(
+                () => provider.GetCompiler());
+            Assert.Equal(expected, exception.Message);
+        }
+    }
+}

test/Microsoft.AspNetCore.Mvc.Razor.Test/Internal/RazorViewCompilerTest.cs

@@ -0,0 +1,527 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System;
+using System.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
+using Microsoft.AspNetCore.Mvc.ApplicationParts;
+using Microsoft.AspNetCore.Mvc.Razor.Compilation;
+using Microsoft.AspNetCore.Razor.Language;
+using Microsoft.CodeAnalysis;
+using Microsoft.Extensions.Logging.Abstractions;
+using Xunit;
+
+namespace Microsoft.AspNetCore.Mvc.Razor.Internal
+{
+    public class RazorViewCompilerTest
+    {
+        [Fact]
+        public async Task CompileAsync_ReturnsResultWithNullAttribute_IfFileIsNotFoundInFileSystem()
+        {
+            // Arrange
+            var path = "/file/does-not-exist";
+            var fileProvider = new TestFileProvider();
+            var viewCompiler = GetViewCompiler(fileProvider);
+
+            // Act
+            var result1 = await viewCompiler.CompileAsync(path);
+            var result2 = await viewCompiler.CompileAsync(path);
+
+            // Assert
+            Assert.Same(result1, result2);
+            Assert.Null(result1.ViewAttribute);
+            Assert.Collection(result1.ExpirationTokens,
+                token => Assert.Equal(fileProvider.GetChangeToken(path), token));
+        }
+
+        [Fact]
+        public async Task CompileAsync_AddsChangeTokensForViewStartsIfFileExists()
+        {
+            // Arrange
+            var path = "/file/exists/FilePath.cshtml";
+            var fileProvider = new TestFileProvider();
+            fileProvider.AddFile(path, "Content");
+            var viewCompiler = GetViewCompiler(fileProvider);
+
+            // Act
+            var result = await viewCompiler.CompileAsync(path);
+
+            // Assert
+            Assert.NotNull(result.ViewAttribute);
+            Assert.Collection(result.ExpirationTokens,
+                token => Assert.Same(fileProvider.GetChangeToken(path), token),
+                token => Assert.Same(fileProvider.GetChangeToken("/file/exists/_ViewImports.cshtml"), token),
+                token => Assert.Same(fileProvider.GetChangeToken("/file/_ViewImports.cshtml"), token),
+                token => Assert.Same(fileProvider.GetChangeToken("/_ViewImports.cshtml"), token));
+        }
+
+        [Theory]
+        [InlineData("/Areas/Finances/Views/Home/Index.cshtml")]
+        [InlineData(@"Areas\Finances\Views\Home\Index.cshtml")]
+        [InlineData(@"\Areas\Finances\Views\Home\Index.cshtml")]
+        [InlineData(@"\Areas\Finances\Views/Home\Index.cshtml")]
+        public async Task CompileAsync_NormalizesPathSepartorForPaths(string relativePath)
+        {
+            // Arrange
+            var viewPath = "/Areas/Finances/Views/Home/Index.cshtml";
+            var fileProvider = new TestFileProvider();
+            fileProvider.AddFile(viewPath, "some content");
+            var viewCompiler = GetViewCompiler(fileProvider);
+
+            // Act - 1
+            var result1 = await viewCompiler.CompileAsync(@"Areas\Finances\Views\Home\Index.cshtml");
+
+            // Act - 2
+            viewCompiler.Compile = _ => throw new Exception("Can't call me");
+            var result2 = await viewCompiler.CompileAsync(relativePath);
+
+            // Assert - 2
+            Assert.Same(result1, result2);
+        }
+
+        [Fact]
+        public async Task CompileAsync_InvalidatesCache_IfChangeTokenExpires()
+        {
+            // Arrange
+            var path = "/Views/Home/Index.cshtml";
+            var fileProvider = new TestFileProvider();
+            var fileInfo = fileProvider.AddFile(path, "some content");
+            var viewCompiler = GetViewCompiler(fileProvider);
+
+            // Act 1
+            var result1 = await viewCompiler.CompileAsync(path);
+
+            // Assert 1
+            Assert.NotNull(result1.ViewAttribute);
+
+            // Act 2
+            fileProvider.DeleteFile(path);
+            fileProvider.GetChangeToken(path).HasChanged = true;
+            viewCompiler.Compile = _ => throw new Exception("Can't call me");
+            var result2 = await viewCompiler.CompileAsync(path);
+
+            // Assert 2
+            Assert.NotSame(result1, result2);
+            Assert.Null(result2.ViewAttribute);
+        }
+
+        [Fact]
+        public async Task CompileAsync_ReturnsNewResultIfFileWasModified()
+        {
+            // Arrange
+            var path = "/Views/Home/Index.cshtml";
+            var fileProvider = new TestFileProvider();
+            var fileInfo = fileProvider.AddFile(path, "some content");
+            var viewCompiler = GetViewCompiler(fileProvider);
+            var expected2 = new CompiledViewDescriptor();
+
+            // Act 1
+            var result1 = await viewCompiler.CompileAsync(path);
+
+            // Assert 1
+            Assert.NotNull(result1.ViewAttribute);
+
+            // Act 2
+            fileProvider.GetChangeToken(path).HasChanged = true;
+            viewCompiler.Compile = _ => expected2;
+            var result2 = await viewCompiler.CompileAsync(path);
+
+            // Assert 2
+            Assert.NotSame(result1, result2);
+            Assert.Same(expected2, result2);
+        }
+
+        [Fact]
+        public async Task CompileAsync_ReturnsNewResult_IfAncestorViewImportsWereModified()
+        {
+            // Arrange
+            var path = "/Views/Home/Index.cshtml";
+            var fileProvider = new TestFileProvider();
+            var fileInfo = fileProvider.AddFile(path, "some content");
+            var viewCompiler = GetViewCompiler(fileProvider);
+            var expected2 = new CompiledViewDescriptor();
+
+            // Act 1
+            var result1 = await viewCompiler.CompileAsync(path);
+
+            // Assert 1
+            Assert.NotNull(result1.ViewAttribute);
+
+            // Act 2
+            fileProvider.GetChangeToken("/Views/_ViewImports.cshtml").HasChanged = true;
+            viewCompiler.Compile = _ => expected2;
+            var result2 = await viewCompiler.CompileAsync(path);
+
+            // Assert 2
+            Assert.NotSame(result1, result2);
+            Assert.Same(expected2, result2);
+        }
+
+        [Fact]
+        public async Task CompileAsync_ReturnsPrecompiledViews()
+        {
+            // Arrange
+            var path = "/Views/Home/Index.cshtml";
+            var fileProvider = new TestFileProvider();
+            var fileInfo = fileProvider.AddFile(path, "some content");
+            var precompiledView = new CompiledViewDescriptor
+            {
+                RelativePath = path,
+            };
+            var viewCompiler = GetViewCompiler(fileProvider, precompiledViews: new[] { precompiledView });
+
+            // Act
+            var result = await viewCompiler.CompileAsync(path);
+
+            // Assert
+            Assert.Same(precompiledView, result);
+        }
+
+        [Fact]
+        public async Task CompileAsync_DoesNotRecompile_IfFileTriggerWasSetForPrecompiledView()
+        {
+            // Arrange
+            var path = "/Views/Home/Index.cshtml";
+            var fileProvider = new TestFileProvider();
+            var fileInfo = fileProvider.AddFile(path, "some content");
+            var precompiledView = new CompiledViewDescriptor
+            {
+                RelativePath = path,
+            };
+            var viewCompiler = GetViewCompiler(fileProvider, precompiledViews: new[] { precompiledView });
+
+            // Act
+            fileProvider.Watch(path);
+            fileProvider.GetChangeToken(path).HasChanged = true;
+            var result = await viewCompiler.CompileAsync(path);
+
+            // Assert
+            Assert.Same(precompiledView, result);
+        }
+
+
+        [Fact]
+        public async Task GetOrAdd_AllowsConcurrentCompilationOfMultipleRazorPages()
+        {
+            // Arrange
+            var path1 = "/Views/Home/Index.cshtml";
+            var path2 = "/Views/Home/About.cshtml";
+            var waitDuration = TimeSpan.FromSeconds(20);
+            var fileProvider = new TestFileProvider();
+            fileProvider.AddFile(path1, "Index content");
+            fileProvider.AddFile(path2, "About content");
+            var resetEvent1 = new AutoResetEvent(initialState: false);
+            var resetEvent2 = new ManualResetEvent(initialState: false);
+            var cache = GetViewCompiler(fileProvider);
+            var compilingOne = false;
+            var compilingTwo = false;
+            var result1 = new CompiledViewDescriptor();
+            var result2 = new CompiledViewDescriptor();
+
+            cache.Compile = path =>
+            {
+                if (path == path1)
+                {
+                    compilingOne = true;
+
+                    // Event 2
+                    Assert.True(resetEvent1.WaitOne(waitDuration));
+
+                    // Event 3
+                    Assert.True(resetEvent2.Set());
+
+                    // Event 6
+                    Assert.True(resetEvent1.WaitOne(waitDuration));
+
+                    Assert.True(compilingTwo);
+
+                    return result1;
+                }
+                else if (path == path2)
+                {
+                    compilingTwo = true;
+
+                    // Event 4
+                    Assert.True(resetEvent2.WaitOne(waitDuration));
+
+                    // Event 5
+                    Assert.True(resetEvent1.Set());
+
+                    Assert.True(compilingOne);
+
+                    return result2;
+                }
+                else
+                {
+                    throw new Exception();
+                }
+            };
+
+            // Act
+            var task1 = Task.Run(() => cache.CompileAsync(path1));
+            var task2 = Task.Run(() => cache.CompileAsync(path2));
+
+            // Event 1
+            resetEvent1.Set();
+
+            await Task.WhenAll(task1, task2);
+
+            // Assert
+            Assert.True(compilingOne);
+            Assert.True(compilingTwo);
+            Assert.Same(result1, task1.Result);
+            Assert.Same(result2, task2.Result);
+        }
+
+        [Fact]
+        public async Task CompileAsync_DoesNotCreateMultipleCompilationResults_ForConcurrentInvocations()
+        {
+            // Arrange
+            var path = "/Views/Home/Index.cshtml";
+            var waitDuration = TimeSpan.FromSeconds(20);
+            var fileProvider = new TestFileProvider();
+            fileProvider.AddFile(path, "some content");
+            var resetEvent1 = new ManualResetEvent(initialState: false);
+            var resetEvent2 = new ManualResetEvent(initialState: false);
+            var compiler = GetViewCompiler(fileProvider);
+
+            compiler.Compile = _ =>
+            {
+                // Event 2
+                resetEvent1.WaitOne(waitDuration);
+
+                // Event 3
+                resetEvent2.Set();
+                return new CompiledViewDescriptor();
+            };
+
+            // Act
+            var task1 = Task.Run(() => compiler.CompileAsync(path));
+            var task2 = Task.Run(() =>
+            {
+                // Event 4
+                Assert.True(resetEvent2.WaitOne(waitDuration));
+                return compiler.CompileAsync(path);
+            });
+
+            // Event 1
+            resetEvent1.Set();
+            await Task.WhenAll(task1, task2);
+
+            // Assert
+            var result1 = task1.Result;
+            var result2 = task2.Result;
+            Assert.Same(result1, result2);
+        }
+
+        [Fact]
+        public async Task GetOrAdd_CachesCompilationExceptions()
+        {
+            // Arrange
+            var path = "/Views/Home/Index.cshtml";
+            var fileProvider = new TestFileProvider();
+            fileProvider.AddFile(path, "some content");
+            var exception = new InvalidTimeZoneException();
+            var compiler = GetViewCompiler(fileProvider);
+            compiler.Compile = _ => throw exception;
+
+            // Act and Assert - 1
+            var actual = await Assert.ThrowsAsync<InvalidTimeZoneException>(
+                () => compiler.CompileAsync(path));
+            Assert.Same(exception, actual);
+
+            // Act and Assert - 2
+            compiler.Compile = _ => throw new Exception("Shouldn't be called");
+
+            actual = await Assert.ThrowsAsync<InvalidTimeZoneException>(
+                () => compiler.CompileAsync(path));
+            Assert.Same(exception, actual);
+        }
+
+        [Fact]
+        public void Compile_SucceedsForCSharp7()
+        {
+            // Arrange
+            var content = @"
+public class MyTestType
+{
+    private string _name;
+
+    public string Name
+    {
+        get => _name;
+        set => _name = value ?? throw new System.ArgumentNullException(nameof(value));
+    }
+}";
+            var compiler = GetViewCompiler(new TestFileProvider());
+            var codeDocument = RazorCodeDocument.Create(RazorSourceDocument.Create("razor-content", "filename"));
+
+            // Act
+            var result = compiler.CompileAndEmit(codeDocument, content);
+
+            // Assert
+            var exportedType = Assert.Single(result.ExportedTypes);
+            Assert.Equal("MyTestType", exportedType.Name);
+        }
+
+        [Fact]
+        public void Compile_ReturnsCompilationFailureWithPathsFromLinePragmas()
+        {
+            // Arrange
+            var viewPath = "some-relative-path";
+            var fileContent = "test file content";
+            var content = $@"
+#line 1 ""{viewPath}""
+this should fail";
+
+            var compiler = GetViewCompiler(new TestFileProvider());
+            var codeDocument = RazorCodeDocument.Create(RazorSourceDocument.Create(fileContent, viewPath));
+
+            // Act & Assert
+            var ex = Assert.Throws<CompilationFailedException>(() => compiler.CompileAndEmit(codeDocument, content));
+
+            var compilationFailure = Assert.Single(ex.CompilationFailures);
+            Assert.Equal(viewPath, compilationFailure.SourceFilePath);
+            Assert.Equal(fileContent, compilationFailure.SourceFileContent);
+        }
+
+        [Fact]
+        public void Compile_ReturnsGeneratedCodePath_IfLinePragmaIsNotAvailable()
+        {
+            // Arrange
+            var viewPath = "some-relative-path";
+            var fileContent = "file content";
+            var content = "this should fail";
+
+            var compiler = GetViewCompiler(new TestFileProvider());
+            var codeDocument = RazorCodeDocument.Create(RazorSourceDocument.Create(fileContent, viewPath));
+
+            // Act & Assert
+            var ex = Assert.Throws<CompilationFailedException>(() => compiler.CompileAndEmit(codeDocument, content));
+
+            var compilationFailure = Assert.Single(ex.CompilationFailures);
+            Assert.Equal("Generated Code", compilationFailure.SourceFilePath);
+            Assert.Equal(content, compilationFailure.SourceFileContent);
+        }
+
+        [Fact]
+        public void Compile_InvokessCallback()
+        {
+            // Arrange
+            var content = "public class MyTestType  {}";
+            var callbackInvoked = false;
+            var compiler = GetViewCompiler(
+                new TestFileProvider(),
+                context =>
+                {
+                    callbackInvoked = true;
+                });
+            var codeDocument = RazorCodeDocument.Create(RazorSourceDocument.Create("some-content", "some-path"));
+
+            // Act
+            var result = compiler.CompileAndEmit(codeDocument, content);
+
+            // Assert
+            Assert.True(callbackInvoked);
+        }
+
+        [Fact]
+        public void Compile_SucceedsIfReferencesAreAddedInCallback()
+        {
+            // Arrange
+            Action<RoslynCompilationContext> compilationCallback = context =>
+            {
+                var assemblyLocation = typeof(object).Assembly.Location;
+
+                context.Compilation = context
+                    .Compilation
+                    .AddReferences(MetadataReference.CreateFromFile(assemblyLocation));
+            };
+
+            var applicationPartManager = new ApplicationPartManager();
+            var referenceManager = new RazorReferenceManager(
+                applicationPartManager,
+                new TestOptionsManager<RazorViewEngineOptions>());
+            var compiler = GetViewCompiler(
+                compilationCallback: compilationCallback,
+                referenceManager: referenceManager);
+
+            var codeDocument = RazorCodeDocument.Create(RazorSourceDocument.Create("Hello world", "some-relative-path.cshtml"));
+
+            // Act
+            var result = compiler.CompileAndEmit(codeDocument, "public class Test {}");
+
+            // Assert
+            Assert.NotNull(result);
+        }
+
+        private static TestRazorViewCompiler GetViewCompiler(
+            TestFileProvider fileProvider = null,
+            Action<RoslynCompilationContext> compilationCallback = null,
+            RazorReferenceManager referenceManager = null,
+            IList<CompiledViewDescriptor> precompiledViews = null)
+        {
+            fileProvider = fileProvider ?? new TestFileProvider();
+            compilationCallback = compilationCallback ?? (_ => { });
+            var options = new TestOptionsManager<RazorViewEngineOptions>();
+            if  (referenceManager == null)
+            {
+                var applicationPartManager = new ApplicationPartManager();
+                var assembly = typeof(RazorViewCompilerTest).Assembly;
+                applicationPartManager.ApplicationParts.Add(new AssemblyPart(assembly));
+                applicationPartManager.FeatureProviders.Add(new MetadataReferenceFeatureProvider());
+
+                referenceManager = new RazorReferenceManager(applicationPartManager, options);
+            }
+
+            precompiledViews = precompiledViews ?? Array.Empty<CompiledViewDescriptor>();
+
+            var projectSystem = new FileProviderRazorProject(fileProvider);
+            var templateEngine = new RazorTemplateEngine(RazorEngine.Create(), projectSystem)
+            {
+                Options =
+                {
+                    ImportsFileName = "_ViewImports.cshtml",
+                }
+            };
+            var viewCompiler = new TestRazorViewCompiler(
+                fileProvider,
+                templateEngine,
+                new CSharpCompiler(referenceManager, options),
+                compilationCallback,
+                precompiledViews);
+            return viewCompiler;
+        }
+
+        private class TestRazorViewCompiler : RazorViewCompiler
+        {
+            public TestRazorViewCompiler(
+                TestFileProvider fileProvider,
+                RazorTemplateEngine templateEngine,
+                CSharpCompiler csharpCompiler,
+                Action<RoslynCompilationContext> compilationCallback,
+                IList<CompiledViewDescriptor> precompiledViews,
+                Func<string, CompiledViewDescriptor> compile = null) :
+                base(fileProvider, templateEngine, csharpCompiler, compilationCallback, precompiledViews, NullLogger.Instance)
+            {
+                Compile = compile;
+                if (Compile == null)
+                {
+                    Compile = path => new CompiledViewDescriptor
+                    {
+                        RelativePath = path,
+                        ViewAttribute = new RazorViewAttribute(path, typeof(object)),
+                    };
+                }
+            }
+
+            public Func<string, CompiledViewDescriptor> Compile { get; set; }
+
+            protected override CompiledViewDescriptor CompileAndEmit(string relativePath)
+            {
+                return Compile(relativePath);
+            }
+        }
+    }
+}

test/Microsoft.AspNetCore.Mvc.Razor.Test/Internal/ReferenceManagerTest.cs

@@ -7,8 +7,6 @@ using Microsoft.AspNetCore.Mvc.ApplicationParts;
 using Microsoft.AspNetCore.Mvc.Razor.Compilation;
 using Microsoft.AspNetCore.Mvc.Razor.Internal;
 using Microsoft.CodeAnalysis;
-using Microsoft.Extensions.Options;
-using Moq;
 using Xunit;
 
 namespace Microsoft.AspNetCore.Mvc.Razor.Test.Internal
@@ -31,7 +29,9 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Test.Internal
             var expectedReferenceDisplays = partReferences
                 .Concat(new[] { objectAssemblyMetadataReference })
                 .Select(r => r.Display);
-            var referenceManager = new RazorReferenceManager(applicationPartManager, GetAccessor(options));
+            var referenceManager = new RazorReferenceManager(
+                applicationPartManager,
+                new TestOptionsManager<RazorViewEngineOptions>(options));
 
             // Act
             var references = referenceManager.CompilationReferences;
@@ -44,18 +44,11 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Test.Internal
         private static ApplicationPartManager GetApplicationPartManager()
         {
             var applicationPartManager = new ApplicationPartManager();
-            var assembly = typeof(DefaultRoslynCompilationServiceTest).GetTypeInfo().Assembly;
+            var assembly = typeof(ReferenceManagerTest).GetTypeInfo().Assembly;
             applicationPartManager.ApplicationParts.Add(new AssemblyPart(assembly));
             applicationPartManager.FeatureProviders.Add(new MetadataReferenceFeatureProvider());
 
             return applicationPartManager;
         }
-
-        private static IOptions<RazorViewEngineOptions> GetAccessor(RazorViewEngineOptions options)
-        {
-            var optionsAccessor = new Mock<IOptions<RazorViewEngineOptions>>();
-            optionsAccessor.SetupGet(a => a.Value).Returns(options);
-            return optionsAccessor.Object;
-        }
     }
 }

test/Microsoft.AspNetCore.Mvc.Razor.Test/Internal/ViewPathTest.cs

@@ -0,0 +1,36 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using Xunit;
+
+namespace Microsoft.AspNetCore.Mvc.Razor.Internal
+{
+    public class ViewPathTest
+    {
+        [Theory]
+        [InlineData("/Views/Home/Index.cshtml")]
+        [InlineData("\\Views/Home/Index.cshtml")]
+        [InlineData("\\Views\\Home/Index.cshtml")]
+        [InlineData("\\Views\\Home\\Index.cshtml")]
+        public void NormalizePath_NormalizesSlashes(string input)
+        {
+            // Act
+            var normalizedPath = ViewPath.NormalizePath(input);
+
+            // Assert
+            Assert.Equal("/Views/Home/Index.cshtml", normalizedPath);
+        }
+
+        [Theory]
+        [InlineData("Views/Home/Index.cshtml")]
+        [InlineData("Views\\Home\\Index.cshtml")]
+        public void NormalizePath_AppendsLeadingSlash(string input)
+        {
+            // Act
+            var normalizedPath = ViewPath.NormalizePath(input);
+
+            // Assert
+            Assert.Equal("/Views/Home/Index.cshtml", normalizedPath);
+        }
+    }
+}

test/Microsoft.AspNetCore.Mvc.RazorPages.Test/Internal/CompiledPageApplicationModelProviderTest.cs

@@ -5,6 +5,8 @@ using System;
 using System.Collections.Generic;
 using Microsoft.AspNetCore.Mvc.ApplicationModels;
 using Microsoft.AspNetCore.Mvc.ApplicationParts;
+using Microsoft.AspNetCore.Mvc.Razor.Compilation;
+using Microsoft.AspNetCore.Mvc.RazorPages.Infrastructure;
 using Xunit;
 
 namespace Microsoft.AspNetCore.Mvc.RazorPages.Internal
@@ -15,12 +17,12 @@ namespace Microsoft.AspNetCore.Mvc.RazorPages.Internal
         public void OnProvidersExecuting_AddsModelsForCompiledViews()
         {
             // Arrange
-            var info = new[]
+            var descriptors = new[]
             {
-                new CompiledPageInfo("/Pages/About.cshtml", typeof(object), routePrefix: string.Empty),
+                GetDescriptor("/Pages/About.cshtml"),
-                new CompiledPageInfo("/Pages/Home.cshtml", typeof(object), "some-prefix"),
+                GetDescriptor("/Pages/Home.cshtml", "some-prefix"),
             };
-            var provider = new TestCompiledPageApplicationModelProvider(info, new RazorPagesOptions());
+            var provider = new TestCompiledPageApplicationModelProvider(descriptors, new RazorPagesOptions());
             var context = new PageApplicationModelProviderContext();
 
             // Act
@@ -48,12 +50,12 @@ namespace Microsoft.AspNetCore.Mvc.RazorPages.Internal
         public void OnProvidersExecuting_AddsMultipleSelectorsForIndexPage_WithIndexAtRoot()
         {
             // Arrange
-            var info = new[]
+            var descriptors = new[]
             {
-                new CompiledPageInfo("/Pages/Index.cshtml", typeof(object), routePrefix: string.Empty),
+                GetDescriptor("/Pages/Index.cshtml"),
-                new CompiledPageInfo("/Pages/Admin/Index.cshtml", typeof(object), "some-template"),
+                GetDescriptor("/Pages/Admin/Index.cshtml", "some-template"),
             };
-            var provider = new TestCompiledPageApplicationModelProvider(info, new RazorPagesOptions { RootDirectory = "/" });
+            var provider = new TestCompiledPageApplicationModelProvider(descriptors, new RazorPagesOptions { RootDirectory = "/" });
             var context = new PageApplicationModelProviderContext();
 
             // Act
@@ -83,12 +85,12 @@ namespace Microsoft.AspNetCore.Mvc.RazorPages.Internal
         public void OnProvidersExecuting_AddsMultipleSelectorsForIndexPage()
         {
             // Arrange
-            var info = new[]
+            var descriptors = new[]
             {
-                new CompiledPageInfo("/Pages/Index.cshtml", typeof(object), routePrefix: string.Empty),
+                GetDescriptor("/Pages/Index.cshtml"),
-                new CompiledPageInfo("/Pages/Admin/Index.cshtml", typeof(object), "some-template"),
+                GetDescriptor("/Pages/Admin/Index.cshtml", "some-template"),
             };
-            var provider = new TestCompiledPageApplicationModelProvider(info, new RazorPagesOptions());
+            var provider = new TestCompiledPageApplicationModelProvider(descriptors, new RazorPagesOptions());
             var context = new PageApplicationModelProviderContext();
 
             // Act
@@ -118,12 +120,12 @@ namespace Microsoft.AspNetCore.Mvc.RazorPages.Internal
         public void OnProvidersExecuting_ThrowsIfRouteTemplateHasOverridePattern()
         {
             // Arrange
-            var info = new[]
+            var descriptors = new[]
             {
-                new CompiledPageInfo("/Pages/Index.cshtml", typeof(object), routePrefix: string.Empty),
+                GetDescriptor("/Pages/Index.cshtml"),
-                new CompiledPageInfo("/Pages/Home.cshtml", typeof(object), "/some-prefix"),
+                GetDescriptor("/Pages/Home.cshtml", "/some-prefix"),
             };
-            var provider = new TestCompiledPageApplicationModelProvider(info, new RazorPagesOptions());
+            var provider = new TestCompiledPageApplicationModelProvider(descriptors, new RazorPagesOptions());
             var context = new PageApplicationModelProviderContext();
 
             // Act & Assert
@@ -132,17 +134,27 @@ namespace Microsoft.AspNetCore.Mvc.RazorPages.Internal
                 ex.Message);
         }
 
+        private static CompiledViewDescriptor GetDescriptor(string path, string prefix = "")
+        {
+            return new CompiledViewDescriptor
+            {
+                RelativePath = path,
+                ViewAttribute = new RazorPageAttribute(path, typeof(object), typeof(object), prefix),
+            };
+        }
+
         public class TestCompiledPageApplicationModelProvider : CompiledPageApplicationModelProvider
         {
-            private readonly IEnumerable<CompiledPageInfo> _info;
+            private readonly IEnumerable<CompiledViewDescriptor> _info;
 
-            public TestCompiledPageApplicationModelProvider(IEnumerable<CompiledPageInfo> info, RazorPagesOptions options)
+            public TestCompiledPageApplicationModelProvider(IEnumerable<CompiledViewDescriptor> info, RazorPagesOptions options)
                 : base(new ApplicationPartManager(), new TestOptionsManager<RazorPagesOptions>(options))
             {
                 _info = info;
             }
 
-            protected override IEnumerable<CompiledPageInfo> GetCompiledPages() => _info;
+
+            protected override IEnumerable<CompiledViewDescriptor> GetCompiledPageDescriptors() => _info;
         }
     }
 }

test/Microsoft.AspNetCore.Mvc.RazorPages.Test/Internal/DefaultPageLoaderTest.cs

@@ -8,6 +8,7 @@ using System.Reflection;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Mvc.ActionConstraints;
 using Microsoft.AspNetCore.Mvc.Filters;
+using Microsoft.AspNetCore.Mvc.RazorPages.Infrastructure;
 using Microsoft.AspNetCore.Mvc.Routing;
 using Xunit;
 
@@ -30,7 +31,8 @@ namespace Microsoft.AspNetCore.Mvc.RazorPages.Internal
             };
 
             // Act
-            var actual = DefaultPageLoader.CreateDescriptor(expected, typeof(EmptyPage).GetTypeInfo());
+            var actual = DefaultPageLoader.CreateDescriptor(expected,
+                new RazorPageAttribute(expected.RelativePath, typeof(EmptyPage), null, ""));
 
             // Assert
             Assert.Same(expected.ActionConstraints, actual.ActionConstraints);
@@ -47,10 +49,11 @@ namespace Microsoft.AspNetCore.Mvc.RazorPages.Internal
         public void CreateDescriptor_EmptyPage()
         {
             // Arrange
-            var type = typeof(EmptyPage).GetTypeInfo();
+            var type = typeof(EmptyPage);
 
             // Act
-            var result = DefaultPageLoader.CreateDescriptor(new PageActionDescriptor(), type);
+            var result = DefaultPageLoader.CreateDescriptor(new PageActionDescriptor(),
+                new RazorPageAttribute("/Pages/Index", type, type, ""));
 
             // Assert
             Assert.Empty(result.BoundProperties);
@@ -65,10 +68,11 @@ namespace Microsoft.AspNetCore.Mvc.RazorPages.Internal
         public void CreateDescriptor_EmptyPageModel()
         {
             // Arrange
-            var type = typeof(EmptyPageWithPageModel).GetTypeInfo();
+            var type = typeof(EmptyPageWithPageModel);
 
             // Act
-            var result = DefaultPageLoader.CreateDescriptor(new PageActionDescriptor(), type);
+            var result = DefaultPageLoader.CreateDescriptor(new PageActionDescriptor(),
+                new RazorPageAttribute("/Pages/Index", type, typeof(EmptyPageModel), ""));
 
             // Assert
             Assert.Empty(result.BoundProperties);
@@ -130,10 +134,11 @@ namespace Microsoft.AspNetCore.Mvc.RazorPages.Internal
         public void CreateDescriptor_FindsHandlerMethod_OnModel()
         {
             // Arrange
-            var type = typeof(PageWithHandlerThatGetsIgnored).GetTypeInfo();
+            var type = typeof(PageWithHandlerThatGetsIgnored);
 
             // Act
-            var result = DefaultPageLoader.CreateDescriptor(new PageActionDescriptor(), type);
+            var result = DefaultPageLoader.CreateDescriptor(new PageActionDescriptor(),
+                new RazorPageAttribute("/Pages/Index", type, typeof(ModelWithHandler), ""));
 
             // Assert
             Assert.Collection(result.BoundProperties, p => Assert.Equal("BindMe", p.Name));
@@ -166,10 +171,11 @@ namespace Microsoft.AspNetCore.Mvc.RazorPages.Internal
         public void CreateDescriptor_FindsHandlerMethodOnPage_WhenModelHasNoHandlers()
         {
             // Arrange
-            var type = typeof(PageWithHandler).GetTypeInfo();
+            var type = typeof(PageWithHandler);
 
             // Act
-            var result = DefaultPageLoader.CreateDescriptor(new PageActionDescriptor(), type);
+            var result = DefaultPageLoader.CreateDescriptor(new PageActionDescriptor(),
+                new RazorPageAttribute("/Pages/Index", type, typeof(PocoModel), ""));
 
             // Assert
             Assert.Collection(result.BoundProperties, p => Assert.Equal("BindMe", p.Name));
@@ -581,7 +587,7 @@ namespace Microsoft.AspNetCore.Mvc.RazorPages.Internal
 
             public int IgnoreMe { get; set; }
         }
-        
+
         [Fact]
         public void CreateBoundProperties_SupportsGet_OnClass()
         {