Change final code documents to not contain non-existent imports.

- Existent imports are imports that have content that contribute to the processing of a Razor document. Prior to this we had a legacy expectation that code documents had empty markers in them for all of their import locations. This proved troublesome when cross-referencing files that had file paths and were supposed to be existent but weren't in metadata. Now that we have a project engine with a de-coupled import feature we can rely on the import feature for finding all locations of important files and then strip out any non-existent items.

src/Microsoft.AspNetCore.Razor.Language/DefaultRazorProjectEngine.cs

@@ -65,7 +65,7 @@ namespace Microsoft.AspNetCore.Razor.Language
 
             var importFeature = GetRequiredFeature<IImportProjectFeature>();
             var importItems = importFeature.GetImports(projectItem);
-            var importSourceDocuments = importItems.Select(ConvertToSourceDocument);
+            var importSourceDocuments = GetImportSourceDocuments(importItems);
 
             var parserOptions = GetRequiredFeature<IRazorParserOptionsFactoryProjectFeature>().Create(ConfigureParserOptions);
             var codeGenerationOptions = GetRequiredFeature<IRazorCodeGenerationOptionsFactoryProjectFeature>().Create(ConfigureCodeGenerationOptions);
@@ -84,12 +84,11 @@ namespace Microsoft.AspNetCore.Razor.Language
 
             var importFeature = GetRequiredFeature<IImportProjectFeature>();
             var importItems = importFeature.GetImports(projectItem);
-            var importSourceDocuments = importItems.Select(ConvertToSourceDocument);
+            var importSourceDocuments = GetImportSourceDocuments(importItems);
 
             var parserOptions = GetRequiredFeature<IRazorParserOptionsFactoryProjectFeature>().Create(ConfigureDesignTimeParserOptions);
             var codeGenerationOptions = GetRequiredFeature<IRazorCodeGenerationOptionsFactoryProjectFeature>().Create(ConfigureDesignTimeCodeGenerationOptions);
 
-
             return RazorCodeDocument.Create(sourceDocument, importSourceDocuments, parserOptions, codeGenerationOptions);
         }
 
@@ -138,17 +137,21 @@ namespace Microsoft.AspNetCore.Razor.Language
         }
 
         // Internal for testing
-        internal static RazorSourceDocument ConvertToSourceDocument(RazorProjectItem importItem)
+        internal static IReadOnlyList<RazorSourceDocument> GetImportSourceDocuments(IReadOnlyList<RazorProjectItem> importItems)
         {
-            if (importItem.Exists)
+            var imports = new List<RazorSourceDocument>();
+            for (var i = 0; i < importItems.Count; i++)
             {
-                // Normal import, has file paths, content etc.
+                var importItem = importItems[i];
-                return RazorSourceDocument.ReadFrom(importItem);
+
+                if (importItem.Exists)
+                {
+                    var sourceDocument = RazorSourceDocument.ReadFrom(importItem);
+                    imports.Add(sourceDocument);
+                }
             }
 
-            // Marker import, doesn't exist, used as an identifier for "there could be something here".
+            return imports;
-            var sourceDocumentProperties = new RazorSourceDocumentProperties(importItem.FilePath, importItem.RelativePhysicalPath);
-            return RazorSourceDocument.Create(string.Empty, sourceDocumentProperties);
         }
     }
 }

test/Microsoft.AspNetCore.Razor.Language.Test/DefaultRazorProjectEngineIntegrationTest.cs

@@ -57,7 +57,7 @@ namespace Microsoft.AspNetCore.Razor.Language
             // Arrange
             var projectItem = new TestRazorProjectItem("Index.cshtml");
 
-            var testImport = Mock.Of<RazorProjectItem>(i => i.Read() == new MemoryStream() && i.FilePath == "testvalue");
+            var testImport = Mock.Of<RazorProjectItem>(i => i.Read() == new MemoryStream() && i.FilePath == "testvalue" && i.Exists == true);
             var importFeature = new Mock<IImportProjectFeature>();
             importFeature
                 .Setup(feature => feature.GetImports(It.IsAny<RazorProjectItem>()))

test/Microsoft.AspNetCore.Razor.Language.Test/DefaultRazorProjectEngineTest.cs

@@ -9,29 +9,19 @@ namespace Microsoft.AspNetCore.Razor.Language
     public class DefaultRazorProjectEngineTest
     {
         [Fact]
-        public void ConvertToSourceDocument_ConvertsNormalImports()
+        public void GetImportSourceDocuments_DoesNotIncludeNonExistentItems()
         {
             // Arrange
-            var projectItem = new TestRazorProjectItem("Index.cshtml");
+            var existingItem = new TestRazorProjectItem("Index.cshtml");
+            var nonExistentItem = Mock.Of<RazorProjectItem>(item => item.Exists == false);
+            var items = new[] { existingItem, nonExistentItem };
 
             // Act
-            var sourceDocument = DefaultRazorProjectEngine.ConvertToSourceDocument(projectItem);
+            var sourceDocuments = DefaultRazorProjectEngine.GetImportSourceDocuments(items);
 
             // Assert
-            Assert.NotNull(sourceDocument);
+            var sourceDocument = Assert.Single(sourceDocuments);
-        }
+            Assert.Equal(existingItem.FilePath, sourceDocument.FilePath);
-
-        [Fact]
-        public void ConvertToSourceDocument_ConvertsMarkerImports()
-        {
-            // Arrange
-            var projectItem = Mock.Of<RazorProjectItem>(item => item.FilePath == "Index.cshtml" && item.Exists == false);
-
-            // Act
-            var sourceDocument = DefaultRazorProjectEngine.ConvertToSourceDocument(projectItem);
-
-            // Assert
-            Assert.NotNull(sourceDocument);
         }
     }
 }