Fix crash in the preview of a code action that modified an .editorconfig

For reasons that aren't entirely clear, when we create a preview of
a code fix, we remove and re-add documents that are being changed when
we produce the PreviewWorkspace. This process had an bug which meant
that the file path of an .editorconfig got dropped, so the resultant
.editorconfig document path was null. This later caused a crash if
the diagnostic engine, when processing the PreviewWorkspace's
new solution, tried asking for a Compilation, since the null path would
get passed to AnalyzerConfig.Parse(), and it would throw.

This was exposed by dotnet#45076; until then if you had a preview of just
an .editorconfig file, nothing would actually be analyzed and so
nothing asked for the Compilation. The crash is "fixed" by dotnet#44331 in
that asking for a Compilation no longer results in a call to
AnalyzerConfig.Parse(); you have to ask for a Compilation and then do
something with a semantic model. By luck, that doesn't happen in the
common repro, but more obscure things absolutely could still fail.

This is being tested by the integration test being added in dotnet#46639. We
don't really have a good unit tests here as far as I can tell, but even
then a unit test really doesn't validate any of the end-to-end here.

Fixes https://devdiv.visualstudio.com/DevDiv/_workitems/edit/1162464

src/EditorFeatures/Core.Wpf/Preview/PreviewFactoryService.cs

@@ -4,6 +4,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Collections.Immutable;
 using System.Composition;
 using System.Diagnostics;
 using System.Linq;
@@ -358,7 +359,7 @@ private async Task<DifferenceViewerPreview> CreateRemovedTextDocumentPreviewView
             double zoomLevel,
             Func<TDocument, CancellationToken, ValueTask<ITextBuffer>> createBufferAsync,
             Func<Solution, DocumentId, Solution> removeTextDocument,
-            Func<Solution, DocumentId, string, SourceText, Solution> addTextDocument,
+            Func<Solution, DocumentInfo, Solution> addTextDocument,
             Action<Workspace, DocumentId> openTextDocument,
             CancellationToken cancellationToken)
             where TDocument : TextDocument
@@ -384,7 +385,13 @@ private async Task<DifferenceViewerPreview> CreateRemovedTextDocumentPreviewView
             // so that all IDE services (colorizer, squiggles etc.) light up in this buffer.
             var leftDocumentId = DocumentId.CreateNewId(document.Project.Id);
             var solutionWithRemovedDocument = removeTextDocument(document.Project.Solution, document.Id);
-            var leftSolution = addTextDocument(solutionWithRemovedDocument, leftDocumentId, document.Name, oldBuffer.AsTextContainer().CurrentText);
+            var leftDocumentInfo = DocumentInfo.Create(
+                leftDocumentId,
+                document.Name,
+                loader: TextLoader.From(TextAndVersion.Create(oldBuffer.AsTextContainer().CurrentText, VersionStamp.Create(), document.FilePath)),
+                filePath: document.FilePath,
+                folders: document.Folders);
+            var leftSolution = addTextDocument(solutionWithRemovedDocument, leftDocumentInfo);
             var leftDocument = leftSolution.GetTextDocument(leftDocumentId);
             var leftWorkspace = new PreviewWorkspace(leftSolution);
             openTextDocument(leftWorkspace, leftDocument.Id);
@@ -400,7 +407,7 @@ public Task<DifferenceViewerPreview> CreateRemovedDocumentPreviewViewAsync(Docum
                 document, zoomLevel,
                 createBufferAsync: (textDocument, cancellationToken) => CreateNewBufferAsync(textDocument, cancellationToken),
                 removeTextDocument: (solution, documentId) => solution.RemoveDocument(documentId),
-                addTextDocument: (solution, documentId, name, text) => solution.AddDocument(documentId, name, text),
+                addTextDocument: (solution, documentInfo) => solution.AddDocument(documentInfo),
                 openTextDocument: (workspace, documentId) => workspace.OpenDocument(documentId),
                 cancellationToken);
         }
@@ -411,7 +418,7 @@ public Task<DifferenceViewerPreview> CreateRemovedAdditionalDocumentPreviewViewA
                 document, zoomLevel,
                 createBufferAsync: CreateNewPlainTextBufferAsync,
                 removeTextDocument: (solution, documentId) => solution.RemoveAdditionalDocument(documentId),
-                addTextDocument: (solution, documentId, name, text) => solution.AddAdditionalDocument(documentId, name, text),
+                addTextDocument: (solution, documentInfo) => solution.AddAdditionalDocument(documentInfo),
                 openTextDocument: (workspace, documentId) => workspace.OpenAdditionalDocument(documentId),
                 cancellationToken);
         }
@@ -422,7 +429,7 @@ public Task<DifferenceViewerPreview> CreateRemovedAnalyzerConfigDocumentPreviewV
                 document, zoomLevel,
                 createBufferAsync: CreateNewPlainTextBufferAsync,
                 removeTextDocument: (solution, documentId) => solution.RemoveAnalyzerConfigDocument(documentId),
-                addTextDocument: (solution, documentId, name, text) => solution.AddAnalyzerConfigDocument(documentId, name, text),
+                addTextDocument: (solution, documentInfo) => solution.AddAnalyzerConfigDocuments(ImmutableArray.Create(documentInfo)),
                 openTextDocument: (workspace, documentId) => workspace.OpenAnalyzerConfigDocument(documentId),
                 cancellationToken);
         }
@@ -528,7 +535,7 @@ private async Task<DifferenceViewerPreview> CreateChangedAdditionalOrAnalyzerCon
             TextDocument newDocument,
             double zoomLevel,
             Func<Solution, DocumentId, Solution> removeTextDocument,
-            Func<Solution, DocumentId, string, SourceText, Solution> addTextDocument,
+            Func<Solution, DocumentInfo, Solution> addTextDocument,
             Func<Solution, DocumentId, SourceText, PreservationMode, Solution> withDocumentText,
             Action<Workspace, DocumentId> openTextDocument,
             CancellationToken cancellationToken)
@@ -571,7 +578,13 @@ private async Task<DifferenceViewerPreview> CreateChangedAdditionalOrAnalyzerCon
             // so that all IDE services (colorizer, squiggles etc.) light up in these buffers.
             var leftDocumentId = DocumentId.CreateNewId(oldDocument.Project.Id);
             var solutionWithRemovedDocument = removeTextDocument(oldDocument.Project.Solution, oldDocument.Id);
-            var leftSolution = addTextDocument(solutionWithRemovedDocument, leftDocumentId, oldDocument.Name, oldBuffer.AsTextContainer().CurrentText);
+            var leftDocumentInfo = DocumentInfo.Create(
+                leftDocumentId,
+                oldDocument.Name,
+                loader: TextLoader.From(TextAndVersion.Create(oldBuffer.AsTextContainer().CurrentText, VersionStamp.Create(), oldDocument.FilePath)),
+                filePath: oldDocument.FilePath,
+                folders: oldDocument.Folders);
+            var leftSolution = addTextDocument(solutionWithRemovedDocument, leftDocumentInfo);
             var leftWorkspace = new PreviewWorkspace(leftSolution);
             openTextDocument(leftWorkspace, leftDocumentId);
 
@@ -591,7 +604,7 @@ public Task<DifferenceViewerPreview> CreateChangedAdditionalDocumentPreviewViewA
             return CreateChangedAdditionalOrAnalyzerConfigDocumentPreviewViewAsync(
                 oldDocument, newDocument, zoomLevel,
                 removeTextDocument: (solution, documentId) => solution.RemoveAdditionalDocument(documentId),
-                addTextDocument: (solution, documentId, name, text) => solution.AddAdditionalDocument(documentId, name, text),
+                addTextDocument: (solution, documentInfo) => solution.AddAdditionalDocument(documentInfo),
                 withDocumentText: (solution, documentId, newText, mode) => solution.WithAdditionalDocumentText(documentId, newText, mode),
                 openTextDocument: (workspace, documentId) => workspace.OpenAdditionalDocument(documentId),
                 cancellationToken);
@@ -602,7 +615,7 @@ public Task<DifferenceViewerPreview> CreateChangedAnalyzerConfigDocumentPreviewV
             return CreateChangedAdditionalOrAnalyzerConfigDocumentPreviewViewAsync(
                 oldDocument, newDocument, zoomLevel,
                 removeTextDocument: (solution, documentId) => solution.RemoveAnalyzerConfigDocument(documentId),
-                addTextDocument: (solution, documentId, name, text) => solution.AddAnalyzerConfigDocument(documentId, name, text),
+                addTextDocument: (solution, documentInfo) => solution.AddAnalyzerConfigDocuments(ImmutableArray.Create(documentInfo)),
                 withDocumentText: (solution, documentId, newText, mode) => solution.WithAnalyzerConfigDocumentText(documentId, newText, mode),
                 openTextDocument: (workspace, documentId) => workspace.OpenAnalyzerConfigDocument(documentId),
                 cancellationToken);