Clean up error messages for using TypeScript syntax in JavaScr… (#35254)

* Fix up quotation marks in error messages in JavaScript files.

* Accepted baselines.

* Typescript -> TypeScript

* Accepted baselines.

* Migrate syntactic diagnostics tests to baselining tests.

* Accepted baselines.

* Update diagnosticMessages.json

* Removed markers.

* Add ability to baseline both semantic and syntactic diagnostics.

* Fix up broken diagnostics when using a server LS.

* Accepted baselines.

* Lints.

* Fake up sourcefile objects in the tsserver session client instead.

* Fewer allocations.

src/harness/client.ts

@@ -374,12 +374,14 @@ namespace ts.server {
         private getDiagnostics(file: string, command: CommandNames): DiagnosticWithLocation[] {
             const request = this.processRequest<protocol.SyntacticDiagnosticsSyncRequest | protocol.SemanticDiagnosticsSyncRequest | protocol.SuggestionDiagnosticsSyncRequest>(command, { file, includeLinePosition: true });
             const response = this.processResponse<protocol.SyntacticDiagnosticsSyncResponse | protocol.SemanticDiagnosticsSyncResponse | protocol.SuggestionDiagnosticsSyncResponse>(request);
+            const sourceText = getSnapshotText(this.host.getScriptSnapshot(file)!);
+            const fakeSourceFile = { fileName: file, text: sourceText } as SourceFile; // Warning! This is a huge lie!
 
             return (<protocol.DiagnosticWithLinePosition[]>response.body).map((entry): DiagnosticWithLocation => {
                 const category = firstDefined(Object.keys(DiagnosticCategory), id =>
                     isString(id) && entry.category === id.toLowerCase() ? (<any>DiagnosticCategory)[id] : undefined);
                 return {
-                    file: undefined!, // TODO: GH#18217
+                    file: fakeSourceFile,
                     start: entry.start,
                     length: entry.length,
                     messageText: entry.message,
@@ -518,14 +520,14 @@ namespace ts.server {
             return notImplemented();
         }
 
-        getSignatureHelpItems(fileName: string, position: number): SignatureHelpItems {
+        getSignatureHelpItems(fileName: string, position: number): SignatureHelpItems | undefined {
             const args: protocol.SignatureHelpRequestArgs = this.createFileLocationRequestArgs(fileName, position);
 
             const request = this.processRequest<protocol.SignatureHelpRequest>(CommandNames.SignatureHelp, args);
             const response = this.processResponse<protocol.SignatureHelpResponse>(request);
 
             if (!response.body) {
-                return undefined!; // TODO: GH#18217
+                return undefined;
             }
 
             const { items, applicableSpan: encodedApplicableSpan, selectedItemIndex, argumentIndex, argumentCount } = response.body;

src/harness/fourslash.ts

@@ -221,7 +221,7 @@ namespace FourSlash {
             }
         }
 
-        constructor(private basePath: string, private testType: FourSlashTestType, public testData: FourSlashData) {
+        constructor(private originalInputFileName: string, private basePath: string, private testType: FourSlashTestType, public testData: FourSlashData) {
             // Create a new Services Adapter
             this.cancellationToken = new TestCancellationToken();
             let compilationOptions = convertGlobalOptionsToCompilerOptions(this.testData.globalOptions);
@@ -1475,7 +1475,7 @@ namespace FourSlash {
         }
 
         public baselineCurrentFileBreakpointLocations() {
-            const baselineFile = this.getBaselineFileName().replace("breakpointValidation", "bpSpan");
+            const baselineFile = this.getBaselineFileNameForInternalFourslashFile().replace("breakpointValidation", "bpSpan");
             Harness.Baseline.runBaseline(baselineFile, this.baselineCurrentFileLocations(pos => this.getBreakpointStatementLocation(pos)!));
         }
 
@@ -1554,8 +1554,49 @@ namespace FourSlash {
             return result;
         }
 
+        public baselineSyntacticDiagnostics() {
+            const files = this.getCompilerTestFiles();
+            const result = this.getSyntacticDiagnosticBaselineText(files);
+            Harness.Baseline.runBaseline(this.getBaselineFileNameForContainingTestFile(), result);
+        }
+
+        private getCompilerTestFiles() {
+            return ts.map(this.testData.files, ({ content, fileName }) => ({
+                content, unitName: fileName
+            }));
+        }
+
+        public baselineSyntacticAndSemanticDiagnostics() {
+            const files = this.getCompilerTestFiles();
+            const result = this.getSyntacticDiagnosticBaselineText(files)
+                + Harness.IO.newLine()
+                + Harness.IO.newLine()
+                + this.getSemanticDiagnosticBaselineText(files);
+            Harness.Baseline.runBaseline(this.getBaselineFileNameForContainingTestFile(), result);
+        }
+
+        private getSyntacticDiagnosticBaselineText(files: Harness.Compiler.TestFile[]) {
+            const diagnostics = ts.flatMap(files,
+                file => this.languageService.getSyntacticDiagnostics(file.unitName)
+            );
+            const result = `Syntactic Diagnostics for file '${this.originalInputFileName}':`
+                + Harness.IO.newLine()
+                + Harness.Compiler.getErrorBaseline(files, diagnostics, /*pretty*/ false);
+            return result;
+        }
+
+        private getSemanticDiagnosticBaselineText(files: Harness.Compiler.TestFile[]) {
+            const diagnostics = ts.flatMap(files,
+                file => this.languageService.getSemanticDiagnostics(file.unitName)
+            );
+            const result = `Semantic Diagnostics for file '${this.originalInputFileName}':`
+                + Harness.IO.newLine()
+                + Harness.Compiler.getErrorBaseline(files, diagnostics, /*pretty*/ false);
+            return result;
+        }
+
         public baselineQuickInfo() {
-            const baselineFile = this.getBaselineFileName();
+            const baselineFile = this.getBaselineFileNameForInternalFourslashFile();
             Harness.Baseline.runBaseline(
                 baselineFile,
                 stringify(
@@ -1567,7 +1608,7 @@ namespace FourSlash {
 
         public baselineSmartSelection() {
             const n = "\n";
-            const baselineFile = this.getBaselineFileName();
+            const baselineFile = this.getBaselineFileNameForInternalFourslashFile();
             const markers = this.getMarkers();
             const fileContent = this.activeFile.content;
             const text = markers.map(marker => {
@@ -1652,11 +1693,15 @@ namespace FourSlash {
             Harness.IO.log(stringify(help.items[help.selectedItemIndex]));
         }
 
-        private getBaselineFileName() {
+        private getBaselineFileNameForInternalFourslashFile() {
             return this.testData.globalOptions[MetadataOptionNames.baselineFile] ||
                 ts.getBaseFileName(this.activeFile.fileName).replace(ts.Extension.Ts, ".baseline");
         }
 
+        private getBaselineFileNameForContainingTestFile() {
+            return ts.getBaseFileName(this.originalInputFileName).replace(ts.Extension.Ts, ".baseline");
+        }
+
         private getSignatureHelp({ triggerReason }: FourSlashInterface.VerifySignatureHelpOptions): ts.SignatureHelpItems | undefined {
             return this.languageService.getSignatureHelpItems(this.activeFile.fileName, this.currentCaretPosition, {
                 triggerReason
@@ -3263,7 +3308,7 @@ namespace FourSlash {
 
         // Parse out the files and their metadata
         const testData = parseTestData(absoluteBasePath, content, absoluteFileName);
-        const state = new TestState(absoluteBasePath, testType, testData);
+        const state = new TestState(absoluteFileName, absoluteBasePath, testType, testData);
         const output = ts.transpileModule(content, { reportDiagnostics: true, compilerOptions: { target: ts.ScriptTarget.ES2015 } });
         if (output.diagnostics!.length > 0) {
             throw new Error(`Syntax error in ${absoluteBasePath}: ${output.diagnostics![0].messageText}`);
@@ -4122,6 +4167,14 @@ namespace FourSlashInterface {
             this.state.baselineSmartSelection();
         }
 
+        public baselineSyntacticDiagnostics() {
+            this.state.baselineSyntacticDiagnostics();
+        }
+
+        public baselineSyntacticAndSemanticDiagnostics() {
+            this.state.baselineSyntacticAndSemanticDiagnostics();
+        }
+
         public nameOrDottedNameSpanTextIs(text: string) {
             this.state.verifyCurrentNameOrDottedNameSpanText(text);
         }