Some cleanup around FileProviderRazorProject with tests

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

@@ -37,15 +37,7 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Internal
             path = NormalizeAndEnsureValidPath(path);
             var fileInfo = _provider.GetFileInfo(path);
 
-            string relativePhysicalPath = null;
+            return new FileProviderRazorProjectItem(fileInfo, basePath: string.Empty, filePath: path, root: _hostingEnvironment.ContentRootPath);
-            if (fileInfo != null && fileInfo.Exists)
-            {
-                var absoluteBasePath = _hostingEnvironment.ContentRootPath;
-                relativePhysicalPath = fileInfo?.PhysicalPath?.Substring(absoluteBasePath.Length + 1); // Include leading separator
-                relativePhysicalPath = relativePhysicalPath ?? path; // Use the incoming path if the file is not directly accessible
-            }
-
-            return new FileProviderRazorProjectItem(fileInfo, basePath: string.Empty, filePath: path, relativePhysicalPath: relativePhysicalPath);
         }
 
         public override IEnumerable<RazorProjectItem> EnumerateItems(string path)
@@ -58,11 +50,11 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Internal
         {
             if (directory.Exists)
             {
-                foreach (var file in directory)
+                foreach (var fileInfo in directory)
                 {
-                    if (file.IsDirectory)
+                    if (fileInfo.IsDirectory)
                     {
-                        var relativePath = prefix + "/" + file.Name;
+                        var relativePath = prefix + "/" + fileInfo.Name;
                         var subDirectory = _provider.GetDirectoryContents(JoinPath(basePath, relativePath));
                         var children = EnumerateFiles(subDirectory, basePath, relativePath);
                         foreach (var child in children)
@@ -70,14 +62,11 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Internal
                             yield return child;
                         }
                     }
-                    else if (string.Equals(RazorFileExtension, Path.GetExtension(file.Name), StringComparison.OrdinalIgnoreCase))
+                    else if (string.Equals(RazorFileExtension, Path.GetExtension(fileInfo.Name), StringComparison.OrdinalIgnoreCase))
                     {
-                        var filePath = prefix + "/" + file.Name;
+                        var filePath = prefix + "/" + fileInfo.Name;
-                        var absoluteBasePath = _hostingEnvironment.ContentRootPath;
-                        var relativePhysicalPath = file.PhysicalPath?.Substring(absoluteBasePath.Length + 1); // Include leading separator
-                        relativePhysicalPath = relativePhysicalPath ?? filePath; // Use the incoming path if the file is not directly accessible
 
-                        yield return new FileProviderRazorProjectItem(file, basePath, filePath: filePath, relativePhysicalPath: relativePhysicalPath);
+                        yield return new FileProviderRazorProjectItem(fileInfo, basePath, filePath: filePath, root: _hostingEnvironment.ContentRootPath);
                     }
                 }
             }

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

@@ -1,6 +1,7 @@
 // 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.IO;
 using Microsoft.AspNetCore.Razor.Language;
 using Microsoft.Extensions.FileProviders;
@@ -9,12 +10,16 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Internal
 {
     public class FileProviderRazorProjectItem : RazorProjectItem
     {
-        public FileProviderRazorProjectItem(IFileInfo fileInfo, string basePath, string filePath, string relativePhysicalPath)
+        private string _root;
+        private string _relativePhysicalPath;
+        private bool _isRelativePhysicalPathSet;
+
+        public FileProviderRazorProjectItem(IFileInfo fileInfo, string basePath, string filePath, string root)
         {
             FileInfo = fileInfo;
             BasePath = basePath;
             FilePath = filePath;
-            RelativePhysicalPath = relativePhysicalPath;
+            _root = root;
         }
 
         public IFileInfo FileInfo { get; }
@@ -27,7 +32,30 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Internal
 
         public override string PhysicalPath => FileInfo.PhysicalPath;
 
-        public override string RelativePhysicalPath { get; }
+        public override string RelativePhysicalPath
+        {
+            get
+            {
+                if (!_isRelativePhysicalPathSet)
+                {
+                    _isRelativePhysicalPathSet = true;
+
+                    if (Exists)
+                    {
+                        if (_root != null &&
+                            !string.IsNullOrEmpty(PhysicalPath) &&
+                            PhysicalPath.StartsWith(_root, StringComparison.OrdinalIgnoreCase) &&
+                            PhysicalPath.Length > _root.Length &&
+                            (PhysicalPath[_root.Length] == Path.DirectorySeparatorChar || PhysicalPath[_root.Length] == Path.AltDirectorySeparatorChar))
+                        {
+                            _relativePhysicalPath = PhysicalPath.Substring(_root.Length + 1); // Include leading separator
+                        }
+                    }
+                }
+
+                return _relativePhysicalPath;
+            }
+        }
 
         public override Stream Read()
         {

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

@@ -39,7 +39,7 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Internal
 
             // Assert
             var failure = Assert.Single(compilationResult.CompilationFailures);
-            Assert.Equal(viewPath, failure.SourceFilePath);
+            Assert.Equal(Path.Combine("Views", "Home", "Index.cshtml"), failure.SourceFilePath);
             Assert.Collection(failure.Messages,
                 message => Assert.StartsWith(
                     @"Unterminated string literal.",
@@ -143,7 +143,7 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Internal
                 compilationResult.CompilationFailures,
                 failure =>
                 {
-                    Assert.Equal(viewPath, failure.SourceFilePath);
+                    Assert.Equal(Path.Combine("Views", "Home", "Index.cshtml"), failure.SourceFilePath);
                     Assert.Collection(failure.Messages,
                         message =>
                         {

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

@@ -17,8 +17,8 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Internal
         {
             // Arrange
             var fileProvider = new TestFileProvider("BasePath");
-            var file1 = fileProvider.AddFile("File1.txt", "content");
+            var file1 = fileProvider.AddFile("/File1.txt", "content");
-            var file2 = fileProvider.AddFile("File2.js", "content");
+            var file2 = fileProvider.AddFile("/File2.js", "content");
             fileProvider.AddDirectoryContent("/", new IFileInfo[] { file1, file2 });
 
             var accessor = Mock.Of<IRazorViewEngineFileProviderAccessor>(a => a.FileProvider == fileProvider);
@@ -37,9 +37,9 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Internal
         {
             // Arrange
             var fileProvider = new TestFileProvider("BasePath");
-            var file1 = fileProvider.AddFile("File1.cshtml", "content");
+            var file1 = fileProvider.AddFile("/File1.cshtml", "content");
-            var file2 = fileProvider.AddFile("File2.js", "content");
+            var file2 = fileProvider.AddFile("/File2.js", "content");
-            var file3 = fileProvider.AddFile("File3.cshtml", "content");
+            var file3 = fileProvider.AddFile("/File3.cshtml", "content");
             fileProvider.AddDirectoryContent("/", new IFileInfo[] { file1, file2, file3 });
 
             var accessor = Mock.Of<IRazorViewEngineFileProviderAccessor>(a => a.FileProvider == fileProvider);
@@ -84,9 +84,9 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Internal
             };
             fileProvider.AddDirectoryContent("/", new IFileInfo[] { directory1, file1, directory2 });
 
-            var file2 = fileProvider.AddFile(Path.Combine("Level1-Dir1", "File2.cshtml"), "content");
+            var file2 = fileProvider.AddFile("/Level1-Dir1/File2.cshtml", "content");
-            var file3 = fileProvider.AddFile(Path.Combine("Level1-Dir1", "File3.cshtml"), "content");
+            var file3 = fileProvider.AddFile("/Level1-Dir1/File3.cshtml", "content");
-            var file4 = fileProvider.AddFile(Path.Combine("Level1-Dir1", "File4.txt"), "content");
+            var file4 = fileProvider.AddFile("/Level1-Dir1/File4.txt", "content");
             var directory3 = new TestDirectoryFileInfo
             {
                 Name = "Level2-Dir1"
@@ -144,16 +144,16 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Internal
             {
                 Name = "Level1-Dir1",
             };
-            var file1 = fileProvider.AddFile(Path.Combine("BasePath", "File1.cshtml"), "content");
+            var file1 = fileProvider.AddFile("/File1.cshtml", "content");
             var directory2 = new TestDirectoryFileInfo
             {
                 Name = "Level1-Dir2",
             };
             fileProvider.AddDirectoryContent("/", new IFileInfo[] { directory1, file1, directory2 });
 
-            var file2 = fileProvider.AddFile(Path.Combine("Level1-Dir1", "File2.cshtml"), "content");
+            var file2 = fileProvider.AddFile("/Level1-Dir1/File2.cshtml", "content");
-            var file3 = fileProvider.AddFile(Path.Combine("Level1-Dir1", "File3.cshtml"), "content");
+            var file3 = fileProvider.AddFile("/Level1-Dir1/File3.cshtml", "content");
-            var file4 = fileProvider.AddFile(Path.Combine("Level1-Dir1", "File4.txt"), "content");
+            var file4 = fileProvider.AddFile("/Level1-Dir1/File4.txt", "content");
             var directory3 = new TestDirectoryFileInfo
             {
                 Name = "Level2-Dir1"
@@ -188,13 +188,13 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Internal
                 });
         }
 
-        [Fact(Skip = "Need to follow-up https://github.com/aspnet/Mvc/pull/7228")]
+        [Fact]
         public void GetItem_ReturnsFileFromDisk()
         {
             var fileProvider = new TestFileProvider("BasePath");
-            var file1 = fileProvider.AddFile("File1.cshtml", "content");
+            var file1 = fileProvider.AddFile("/File1.cshtml", "content");
-            var file2 = fileProvider.AddFile("File2.js", "content");
+            var file2 = fileProvider.AddFile("/File2.js", "content");
-            var file3 = fileProvider.AddFile("File3.cshtml", "content");
+            var file3 = fileProvider.AddFile("/File3.cshtml", "content");
             fileProvider.AddDirectoryContent("/", new IFileInfo[] { file1, file2, file3 });
 
             var accessor = Mock.Of<IRazorViewEngineFileProviderAccessor>(a => a.FileProvider == fileProvider);
@@ -212,12 +212,36 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Internal
             Assert.Equal("File3.cshtml", item.RelativePhysicalPath);
         }
 
+        [Fact]
+        public void GetItem_PhysicalPathDoesNotStartWithContentRoot_ReturnsNull()
+        {
+            var fileProvider = new TestFileProvider("BasePath2");
+            var file1 = fileProvider.AddFile("/File1.cshtml", "content");
+            var file2 = fileProvider.AddFile("/File2.js", "content");
+            var file3 = fileProvider.AddFile("/File3.cshtml", "content");
+            fileProvider.AddDirectoryContent("/", new IFileInfo[] { file1, file2, file3 });
+
+            var accessor = Mock.Of<IRazorViewEngineFileProviderAccessor>(a => a.FileProvider == fileProvider);
+
+            var razorProject = new FileProviderRazorProject(accessor, Mock.Of<IHostingEnvironment>(e => e.ContentRootPath == "BasePath"));
+
+            // Act
+            var item = razorProject.GetItem("/File3.cshtml");
+
+            // Assert
+            Assert.True(item.Exists);
+            Assert.Equal("/File3.cshtml", item.FilePath);
+            Assert.Equal(string.Empty, item.BasePath);
+            Assert.Equal(Path.Combine("BasePath2", "File3.cshtml"), item.PhysicalPath);
+            Assert.Null(item.RelativePhysicalPath);
+        }
+
         [Fact]
         public void GetItem_ReturnsNotFoundResult()
         {
             // Arrange
             var fileProvider = new TestFileProvider("BasePath");
-            var file = fileProvider.AddFile("SomeFile.cshtml", "content");
+            var file = fileProvider.AddFile("/SomeFile.cshtml", "content");
             fileProvider.AddDirectoryContent("/", new IFileInfo[] { file });
             var accessor = Mock.Of<IRazorViewEngineFileProviderAccessor>(a => a.FileProvider == fileProvider);
 

test/Microsoft.AspNetCore.Mvc.TestCommon/TestFileProvider.cs

@@ -46,7 +46,7 @@ namespace Microsoft.AspNetCore.Mvc.Razor
             var fileInfo = new TestFileInfo
             {
                 Content = contents,
-                PhysicalPath = Path.Combine(Root, path),
+                PhysicalPath = Path.Combine(Root, NormalizeAndEnsureValidPhysicalPath(path)),
                 Name = Path.GetFileName(path),
                 LastModified = DateTime.UtcNow,
             };
@@ -109,6 +109,23 @@ namespace Microsoft.AspNetCore.Mvc.Razor
             return _fileTriggers[filter];
         }
 
+        private static string NormalizeAndEnsureValidPhysicalPath(string filePath)
+        {
+            if (string.IsNullOrEmpty(filePath))
+            {
+                return filePath;
+            }
+
+            filePath = filePath.Replace('/', Path.DirectorySeparatorChar);
+
+            if (filePath[0] == Path.DirectorySeparatorChar)
+            {
+                filePath = filePath.Substring(1);
+            }
+
+            return filePath;
+        }
+
         private class NotFoundFileInfo : IFileInfo
         {
             public bool Exists