Don't use project engines directly in the language server

src/Razor/src/Microsoft.AspNetCore.Razor.LanguageServer/Cohost/CohostDocumentSnapshot.cs

@@ -70,4 +70,12 @@ public bool TryGetGeneratedOutput([NotNullWhen(true)] out RazorCodeDocument? res
         result = _codeDocument;
         return result is not null;
     }
+
+    public IDocumentSnapshot WithText(SourceText text)
+    {
+        var id = _textDocument.Id;
+        var newDocument = _textDocument.Project.Solution.WithAdditionalDocumentText(id, text).GetAdditionalDocument(id).AssumeNotNull();
+
+        return new CohostDocumentSnapshot(newDocument, _projectSnapshot);
+    }
 }

src/Razor/src/Microsoft.AspNetCore.Razor.LanguageServer/Formatting/FormattingContext.cs

@@ -10,7 +10,6 @@
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Razor.Language;
 using Microsoft.AspNetCore.Razor.LanguageServer.Extensions;
-using Microsoft.AspNetCore.Razor.PooledObjects;
 using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.Razor.ProjectSystem;
 using Microsoft.CodeAnalysis.Razor.Workspaces.Extensions;
@@ -27,8 +26,6 @@ internal class FormattingContext : IDisposable
 
     private IReadOnlyList<FormattingSpan>? _formattingSpans;
     private IReadOnlyDictionary<int, IndentationContext>? _indentations;
-    private RazorProjectEngine? _engine;
-    private ImmutableArray<RazorSourceDocument> _importSources;
 
     private FormattingContext(AdhocWorkspaceFactory workspaceFactory, Uri uri, IDocumentSnapshot originalSnapshot, RazorCodeDocument codeDocument, FormattingOptions options,
         bool isFormatOnType, bool automaticallyAddUsings, int hostDocumentIndex, char triggerCharacter)
@@ -44,14 +41,6 @@ private FormattingContext(AdhocWorkspaceFactory workspaceFactory, Uri uri, IDocu
         TriggerCharacter = triggerCharacter;
     }
 
-    private FormattingContext(RazorProjectEngine engine, ImmutableArray<RazorSourceDocument> importSources, AdhocWorkspaceFactory workspaceFactory, Uri uri, IDocumentSnapshot originalSnapshot, RazorCodeDocument codeDocument, FormattingOptions options,
-        bool isFormatOnType, bool automaticallyAddUsings, int hostDocumentIndex, char triggerCharacter)
-        : this(workspaceFactory, uri, originalSnapshot, codeDocument, options, isFormatOnType, automaticallyAddUsings, hostDocumentIndex, triggerCharacter)
-    {
-        _engine = engine;
-        _importSources = importSources;
-    }
-
     public static bool SkipValidateComponents { get; set; }
 
     public Uri Uri { get; }
@@ -281,22 +270,13 @@ public async Task<FormattingContext> WithTextAsync(SourceText changedText)
             throw new ArgumentNullException(nameof(changedText));
         }
 
-        if (_engine is null)
-        {
-            await InitializeProjectEngineAsync().ConfigureAwait(false);
-        }
-
-        Assumes.NotNull(_engine);
-
-        var changedSourceDocument = RazorSourceDocument.Create(changedText, RazorSourceDocumentProperties.Create(OriginalSnapshot.FilePath, OriginalSnapshot.TargetPath));
+        var changedSnapshot = OriginalSnapshot.WithText(changedText);
 
-        var codeDocument = _engine.ProcessDesignTime(changedSourceDocument, OriginalSnapshot.FileKind, _importSources, OriginalSnapshot.Project.TagHelpers);
+        var codeDocument = await changedSnapshot.GetGeneratedOutputAsync().ConfigureAwait(false);
 
         DEBUG_ValidateComponents(CodeDocument, codeDocument);
 
         var newContext = new FormattingContext(
-            _engine,
-            _importSources!,
             _workspaceFactory,
             Uri,
             OriginalSnapshot,
@@ -310,24 +290,6 @@ public async Task<FormattingContext> WithTextAsync(SourceText changedText)
         return newContext;
     }
 
-    private async Task InitializeProjectEngineAsync()
-    {
-        var engine = OriginalSnapshot.Project.GetProjectEngine();
-
-        var imports = OriginalSnapshot.GetImports();
-        using var importSources = new PooledArrayBuilder<RazorSourceDocument>(imports.Length);
-
-        foreach (var import in imports)
-        {
-            var sourceText = await import.GetTextAsync().ConfigureAwait(false);
-            var source = RazorSourceDocument.Create(sourceText, RazorSourceDocumentProperties.Create(import.FilePath, import.TargetPath));
-            importSources.Add(source);
-        }
-
-        _engine = engine;
-        _importSources = importSources.DrainToImmutable();
-    }
-
     /// <summary>
     /// It can be difficult in the testing infrastructure to correct constructs input files that work consistently across
     /// context changes, so this method validates that the number of components isn't changing due to lost tag help info.

src/Razor/src/Microsoft.AspNetCore.Razor.LanguageServer/MapCode/MapCodeEndpoint.cs

@@ -18,7 +18,6 @@
 using Microsoft.AspNetCore.Razor.LanguageServer.Protocol;
 using Microsoft.AspNetCore.Razor.PooledObjects;
 using Microsoft.CodeAnalysis;
-using Microsoft.CodeAnalysis.Razor.ProjectSystem;
 using Microsoft.CodeAnalysis.Razor.Workspaces.Extensions;
 using Microsoft.CodeAnalysis.Text;
 using Microsoft.CommonLanguageServerProtocol.Framework;
@@ -76,11 +75,12 @@ internal sealed class MapCodeEndpoint(
                 continue;
             }
 
-            var (projectEngine, importSources) = await InitializeProjectEngineAsync(documentContext.Snapshot).ConfigureAwait(false);
             var tagHelperContext = await documentContext.GetTagHelperContextAsync(cancellationToken).ConfigureAwait(false);
             var fileKind = FileKinds.GetFileKindFromFilePath(documentContext.FilePath);
             var extension = Path.GetExtension(documentContext.FilePath);
 
+            var snapshot = documentContext.Snapshot;
+
             foreach (var content in mapping.Contents)
             {
                 if (content is null)
@@ -89,8 +89,8 @@ internal sealed class MapCodeEndpoint(
                 }
 
                 // We create a new Razor file based on each content in each mapping order to get the syntax tree that we'll later use to map.
-                var sourceDocument = RazorSourceDocument.Create(content, "Test" + extension);
-                var codeToMap = projectEngine.ProcessDesignTime(sourceDocument, fileKind, importSources, tagHelperContext.TagHelpers);
+                var newSnapshot = snapshot.WithText(SourceText.From(content));
+                var codeToMap = await newSnapshot.GetGeneratedOutputAsync().ConfigureAwait(false);
 
                 var mappingSuccess = await TryMapCodeAsync(
                     codeToMap, mapping.FocusLocations, changes, documentContext, cancellationToken).ConfigureAwait(false);
@@ -241,24 +241,6 @@ private async Task<bool> TryMapCodeAsync(
         return false;
     }
 
-    private static async Task<(RazorProjectEngine projectEngine, ImmutableArray<RazorSourceDocument> importSources)> InitializeProjectEngineAsync(
-        IDocumentSnapshot originalSnapshot)
-    {
-        var engine = originalSnapshot.Project.GetProjectEngine();
-
-        var imports = originalSnapshot.GetImports();
-        using var importSources = new PooledArrayBuilder<RazorSourceDocument>(imports.Length);
-
-        foreach (var import in imports)
-        {
-            var sourceText = await import.GetTextAsync().ConfigureAwait(false);
-            var source = RazorSourceDocument.Create(sourceText, RazorSourceDocumentProperties.Create(import.FilePath, import.TargetPath));
-            importSources.Add(source);
-        }
-
-        return (engine, importSources.DrainToImmutable());
-    }
-
     private static List<SyntaxNode> ExtractValidNodesToMap(SyntaxNode rootNode)
     {
         var validNodesToMap = new List<SyntaxNode>();

src/Razor/src/Microsoft.CodeAnalysis.Razor.Workspaces/ProjectSystem/DocumentSnapshot.cs

@@ -61,4 +61,9 @@ public virtual bool TryGetGeneratedOutput([NotNullWhen(true)] out RazorCodeDocum
         result = null;
         return false;
     }
+
+    public IDocumentSnapshot WithText(SourceText text)
+    {
+        return new DocumentSnapshot(ProjectInternal, State.WithText(text, VersionStamp.Create()));
+    }
 }

src/Razor/src/Microsoft.CodeAnalysis.Razor.Workspaces/ProjectSystem/IDocumentSnapshot.cs

@@ -26,4 +26,6 @@ internal interface IDocumentSnapshot
     bool TryGetText([NotNullWhen(true)] out SourceText? result);
     bool TryGetTextVersion(out VersionStamp result);
     bool TryGetGeneratedOutput([NotNullWhen(true)] out RazorCodeDocument? result);
+
+    IDocumentSnapshot WithText(SourceText text);
 }

src/Razor/src/Microsoft.CodeAnalysis.Razor.Workspaces/ProjectSystem/ImportDocumentSnapshot.cs

@@ -76,4 +76,7 @@ public bool TryGetTextVersion(out VersionStamp result)
 
     public bool TryGetGeneratedOutput([NotNullWhen(true)] out RazorCodeDocument? result)
         => throw new NotSupportedException();
+
+    public IDocumentSnapshot WithText(SourceText text)
+        => throw new NotSupportedException();
 }

src/Razor/test/Microsoft.AspNetCore.Razor.LanguageServer.Test/AutoInsert/OnAutoInsertEndpointTest.NetFx.cs

@@ -363,7 +363,7 @@ private async Task VerifyCSharpOnAutoInsertAsync(string input, string expected,
         TestFileMarkupParser.GetPosition(input, out input, out var cursorPosition);
 
         var codeDocument = CreateCodeDocument(input);
-        var razorFilePath = "file://path/test.razor";
+        var razorFilePath = "C:/path/test.razor";
         var languageServer = await CreateLanguageServerAsync(codeDocument, razorFilePath);
 
         var optionsMonitor = GetOptionsMonitor();

src/Razor/test/Microsoft.AspNetCore.Razor.LanguageServer.Test/CodeActions/CodeActionEndToEndTest.NetFx.cs

@@ -1026,7 +1026,7 @@ private async Task ValidateCodeActionAsync(
     {
         TestFileMarkupParser.GetSpan(input, out input, out var textSpan);
 
-        var razorFilePath = "file://C:/path/test.razor";
+        var razorFilePath = "C:/path/test.razor";
         var codeDocument = CreateCodeDocument(input, filePath: razorFilePath);
         var sourceText = codeDocument.GetSourceText();
         var uri = new Uri(razorFilePath);

src/Razor/test/Microsoft.AspNetCore.Razor.LanguageServer.Test/Formatting_NetFx/FormattingContentValidationPassTest.cs

@@ -155,9 +155,6 @@ private static (RazorCodeDocument, IDocumentSnapshot) CreateCodeDocumentAndSnaps
         documentSnapshot
             .Setup(d => d.GetGeneratedOutputAsync())
             .ReturnsAsync(codeDocument);
-        documentSnapshot
-            .Setup(d => d.Project.GetProjectEngine())
-            .Returns(projectEngine);
         documentSnapshot
             .Setup(d => d.TargetPath)
             .Returns(path);

src/Razor/test/Microsoft.AspNetCore.Razor.LanguageServer.Test/Formatting_NetFx/FormattingDiagnosticValidationPassTest.cs

@@ -158,29 +158,8 @@ private static (RazorCodeDocument, IDocumentSnapshot) CreateCodeDocumentAndSnaps
         var projectEngine = RazorProjectEngine.Create(builder => builder.SetRootNamespace("Test"));
         var codeDocument = projectEngine.ProcessDesignTime(sourceDocument, fileKind, importSources: default, tagHelpers);
 
-        var documentSnapshot = new Mock<IDocumentSnapshot>(MockBehavior.Strict);
-        documentSnapshot
-            .Setup(d => d.GetImports())
-            .Returns(ImmutableArray<IDocumentSnapshot>.Empty);
-        documentSnapshot
-            .Setup(d => d.GetGeneratedOutputAsync())
-            .ReturnsAsync(codeDocument);
-        documentSnapshot
-            .Setup(d => d.Project.GetProjectEngine())
-            .Returns(projectEngine);
-        documentSnapshot
-            .Setup(d => d.TargetPath)
-            .Returns(path);
-        documentSnapshot
-            .Setup(d => d.Project.TagHelpers)
-            .Returns(tagHelpers);
-        documentSnapshot
-            .Setup(d => d.FileKind)
-            .Returns(fileKind);
-        documentSnapshot
-            .Setup(d => d.FilePath)
-            .Returns(path);
-
-        return (codeDocument, documentSnapshot.Object);
+        var documentSnapshot = FormattingTestBase.CreateDocumentSnapshot(path, tagHelpers, fileKind, ImmutableArray<RazorSourceDocument>.Empty, ImmutableArray<IDocumentSnapshot>.Empty, projectEngine, codeDocument);
+
+        return (codeDocument, documentSnapshot);
     }
 }

src/Razor/test/Microsoft.AspNetCore.Razor.LanguageServer.Test/Formatting_NetFx/FormattingTestBase.cs

@@ -267,16 +267,22 @@ @using Microsoft.AspNetCore.Components.Web
             Assert.False(codeDocument.GetCSharpDocument().Diagnostics.Any(), "Error creating document:" + Environment.NewLine + string.Join(Environment.NewLine, codeDocument.GetCSharpDocument().Diagnostics));
         }
 
+        var imports = ImmutableArray.Create(importsSnapshot.Object);
+        var importsDocuments = ImmutableArray.Create(importsDocument);
+        var documentSnapshot = CreateDocumentSnapshot(path, tagHelpers, fileKind, importsDocuments, imports, projectEngine, codeDocument);
+
+        return (codeDocument, documentSnapshot);
+    }
+
+    internal static IDocumentSnapshot CreateDocumentSnapshot(string path, ImmutableArray<TagHelperDescriptor> tagHelpers, string? fileKind, ImmutableArray<RazorSourceDocument> importsDocuments, ImmutableArray<IDocumentSnapshot> imports, RazorProjectEngine projectEngine, RazorCodeDocument codeDocument)
+    {
         var documentSnapshot = new Mock<IDocumentSnapshot>(MockBehavior.Strict);
         documentSnapshot
             .Setup(d => d.GetGeneratedOutputAsync())
             .ReturnsAsync(codeDocument);
         documentSnapshot
             .Setup(d => d.GetImports())
-            .Returns(ImmutableArray.Create(importsSnapshot.Object));
-        documentSnapshot
-            .Setup(d => d.Project.GetProjectEngine())
-            .Returns(projectEngine);
+            .Returns(imports);
         documentSnapshot
             .Setup(d => d.FilePath)
             .Returns(path);
@@ -292,7 +298,14 @@ @using Microsoft.AspNetCore.Components.Web
         documentSnapshot
             .Setup(d => d.FileKind)
             .Returns(fileKind);
-
-        return (codeDocument, documentSnapshot.Object);
+        documentSnapshot
+            .Setup(d => d.WithText(It.IsAny<SourceText>()))
+            .Returns<SourceText>(text =>
+            {
+                var sourceDocument = RazorSourceDocument.Create(text, RazorSourceDocumentProperties.Create(path, path));
+                var codeDocument = projectEngine.ProcessDesignTime(sourceDocument, fileKind, importsDocuments, tagHelpers);
+                return CreateDocumentSnapshot(path, tagHelpers, fileKind, importsDocuments, imports, projectEngine, codeDocument);
+            });
+        return documentSnapshot.Object;
     }
 }

src/Razor/test/Microsoft.AspNetCore.Razor.LanguageServer.Test/MapCode/MapCodeTest.cs

@@ -11,8 +11,6 @@
 using Microsoft.AspNetCore.Razor.LanguageServer.Protocol;
 using Microsoft.AspNetCore.Razor.Test.Common.LanguageServer;
 using Microsoft.AspNetCore.Razor.Test.Common.Mef;
-using Microsoft.AspNetCore.Razor.Test.Common.Workspaces;
-using Microsoft.CodeAnalysis.Razor.Workspaces;
 using Microsoft.CodeAnalysis.Razor.Workspaces.Extensions;
 using Microsoft.CodeAnalysis.Testing;
 using Microsoft.CodeAnalysis.Text;