[typescript-language-features] Region-based semantic diagnostics for TypeScript (#208713)

* WIP

* invalidate diagnostics in range

* check whether should use region based diagnostics

* add ts-expect-errors

* make region opt off by default

* bump to expected 5.6

* update comments to refer to 5.6

* make region diagnostics on by default for insiders

extensions/typescript-language-features/src/configuration/configuration.ts

@@ -124,6 +124,7 @@ export interface TypeScriptServiceConfiguration {
 	readonly localNodePath: string | null;
 	readonly globalNodePath: string | null;
 	readonly workspaceSymbolsExcludeLibrarySymbols: boolean;
+	readonly enableRegionDiagnostics: boolean;
 }
 
 export function areServiceConfigurationsEqual(a: TypeScriptServiceConfiguration, b: TypeScriptServiceConfiguration): boolean {
@@ -162,6 +163,7 @@ export abstract class BaseServiceConfigurationProvider implements ServiceConfigu
 			localNodePath: this.readLocalNodePath(configuration),
 			globalNodePath: this.readGlobalNodePath(configuration),
 			workspaceSymbolsExcludeLibrarySymbols: this.readWorkspaceSymbolsExcludeLibrarySymbols(configuration),
+			enableRegionDiagnostics: this.readEnableRegionDiagnostics(configuration),
 		};
 	}
 
@@ -267,4 +269,8 @@ export abstract class BaseServiceConfigurationProvider implements ServiceConfigu
 	private readWebTypeAcquisition(configuration: vscode.WorkspaceConfiguration): boolean {
 		return configuration.get<boolean>('typescript.tsserver.web.typeAcquisition.enabled', false);
 	}
+
+	private readEnableRegionDiagnostics(configuration: vscode.WorkspaceConfiguration): boolean {
+		return configuration.get<boolean>('typescript.tsserver.enableRegionDiagnostics', true);
+	}
 }

extensions/typescript-language-features/src/languageFeatures/diagnostics.ts

@@ -34,6 +34,7 @@ export const enum DiagnosticKind {
 	Syntax,
 	Semantic,
 	Suggestion,
+	RegionSemantic,
 }
 
 class FileDiagnostics {
@@ -48,7 +49,8 @@ class FileDiagnostics {
 	public updateDiagnostics(
 		language: DiagnosticLanguage,
 		kind: DiagnosticKind,
-		diagnostics: ReadonlyArray<vscode.Diagnostic>
+		diagnostics: ReadonlyArray<vscode.Diagnostic>,
+		ranges: ReadonlyArray<vscode.Range> | undefined
 	): boolean {
 		if (language !== this.language) {
 			this._diagnostics.clear();
@@ -61,6 +63,9 @@ class FileDiagnostics {
 			return false;
 		}
 
+		if (kind === DiagnosticKind.RegionSemantic) {
+			return this.updateRegionDiagnostics(diagnostics, ranges!);
+		}
 		this._diagnostics.set(kind, diagnostics);
 		return true;
 	}
@@ -83,6 +88,23 @@ class FileDiagnostics {
 		}
 	}
 
+	/**
+	 * @param ranges The ranges whose diagnostics were updated.
+	 */
+	private updateRegionDiagnostics(
+		diagnostics: ReadonlyArray<vscode.Diagnostic>,
+		ranges: ReadonlyArray<vscode.Range>): boolean {
+		if (!this._diagnostics.get(DiagnosticKind.Semantic)) {
+			this._diagnostics.set(DiagnosticKind.Semantic, diagnostics);
+			return true;
+		}
+		const oldDiagnostics = this._diagnostics.get(DiagnosticKind.Semantic)!;
+		const newDiagnostics = oldDiagnostics.filter(diag => !ranges.some(range => diag.range.intersection(range)));
+		newDiagnostics.push(...diagnostics);
+		this._diagnostics.set(DiagnosticKind.Semantic, newDiagnostics);
+		return true;
+	}
+
 	private getSuggestionDiagnostics(settings: DiagnosticSettings) {
 		const enableSuggestions = settings.getEnableSuggestions(this.language);
 		return this.get(DiagnosticKind.Suggestion).filter(x => {
@@ -284,15 +306,16 @@ export class DiagnosticsManager extends Disposable {
 		file: vscode.Uri,
 		language: DiagnosticLanguage,
 		kind: DiagnosticKind,
-		diagnostics: ReadonlyArray<vscode.Diagnostic>
+		diagnostics: ReadonlyArray<vscode.Diagnostic>,
+		ranges: ReadonlyArray<vscode.Range> | undefined,
 	): void {
 		let didUpdate = false;
 		const entry = this._diagnostics.get(file);
 		if (entry) {
-			didUpdate = entry.updateDiagnostics(language, kind, diagnostics);
+			didUpdate = entry.updateDiagnostics(language, kind, diagnostics, ranges);
 		} else if (diagnostics.length) {
 			const fileDiagnostics = new FileDiagnostics(file, language);
-			fileDiagnostics.updateDiagnostics(language, kind, diagnostics);
+			fileDiagnostics.updateDiagnostics(language, kind, diagnostics, ranges);
 			this._diagnostics.set(file, fileDiagnostics);
 			didUpdate = true;
 		}

extensions/typescript-language-features/src/languageProvider.ts

@@ -138,7 +138,11 @@ export default class LanguageProvider extends Disposable {
 		this.client.bufferSyncSupport.requestAllDiagnostics();
 	}
 
-	public diagnosticsReceived(diagnosticsKind: DiagnosticKind, file: vscode.Uri, diagnostics: (vscode.Diagnostic & { reportUnnecessary: any; reportDeprecated: any })[]): void {
+	public diagnosticsReceived(
+		diagnosticsKind: DiagnosticKind,
+		file: vscode.Uri,
+		diagnostics: (vscode.Diagnostic & { reportUnnecessary: any; reportDeprecated: any })[],
+		ranges: vscode.Range[] | undefined): void {
 		if (diagnosticsKind !== DiagnosticKind.Syntax && !this.client.hasCapabilityForResource(file, ClientCapability.Semantic)) {
 			return;
 		}
@@ -175,7 +179,7 @@ export default class LanguageProvider extends Disposable {
 				}
 			}
 			return true;
-		}));
+		}), ranges);
 	}
 
 	public configFileDiagnosticsReceived(file: vscode.Uri, diagnostics: vscode.Diagnostic[]): void {

extensions/typescript-language-features/src/tsServer/bufferSyncSupport.ts

@@ -275,12 +275,12 @@ class SyncedBufferMap extends ResourceMap<SyncedBuffer> {
 }
 
 class PendingDiagnostics extends ResourceMap<number> {
-	public getOrderedFileSet(): ResourceMap<void> {
+	public getOrderedFileSet(): ResourceMap<void | vscode.Range[]> {
 		const orderedResources = Array.from(this.entries())
 			.sort((a, b) => a.value - b.value)
 			.map(entry => entry.resource);
 
-		const map = new ResourceMap<void>(this._normalizePath, this.config);
+		const map = new ResourceMap<void | vscode.Range[]>(this._normalizePath, this.config);
 		for (const resource of orderedResources) {
 			map.set(resource, undefined);
 		}
@@ -292,7 +292,7 @@ class GetErrRequest {
 
 	public static executeGetErrRequest(
 		client: ITypeScriptServiceClient,
-		files: ResourceMap<void>,
+		files: ResourceMap<void | vscode.Range[]>,
 		onDone: () => void
 	) {
 		return new GetErrRequest(client, files, onDone);
@@ -303,7 +303,7 @@ class GetErrRequest {
 
 	private constructor(
 		private readonly client: ITypeScriptServiceClient,
-		public readonly files: ResourceMap<void>,
+		public readonly files: ResourceMap<void | vscode.Range[]>,
 		onDone: () => void
 	) {
 		if (!this.isErrorReportingEnabled()) {
@@ -313,19 +313,39 @@ class GetErrRequest {
 		}
 
 		const supportsSyntaxGetErr = this.client.apiVersion.gte(API.v440);
-		const allFiles = coalesce(Array.from(files.entries())
-			.filter(entry => supportsSyntaxGetErr || client.hasCapabilityForResource(entry.resource, ClientCapability.Semantic))
+		const fileEntries = Array.from(files.entries()).filter(entry => supportsSyntaxGetErr || client.hasCapabilityForResource(entry.resource, ClientCapability.Semantic));
+		const allFiles = coalesce(fileEntries
 			.map(entry => client.toTsFilePath(entry.resource)));
 
 		if (!allFiles.length) {
 			this._done = true;
 			setImmediate(onDone);
 		} else {
-			const request = this.areProjectDiagnosticsEnabled()
+			let request;
+			if (this.areProjectDiagnosticsEnabled()) {
 				// Note that geterrForProject is almost certainly not the api we want here as it ends up computing far
 				// too many diagnostics
-				? client.executeAsync('geterrForProject', { delay: 0, file: allFiles[0] }, this._token.token)
-				: client.executeAsync('geterr', { delay: 0, files: allFiles }, this._token.token);
+				request = client.executeAsync('geterrForProject', { delay: 0, file: allFiles[0] }, this._token.token);
+			}
+			else {
+				let requestFiles;
+				if (this.areRegionDiagnosticsEnabled()) {
+					requestFiles = coalesce(fileEntries
+						.map(entry => {
+							const file = client.toTsFilePath(entry.resource);
+							const ranges = entry.value;
+							if (file && ranges) {
+								return typeConverters.Range.toFileRangesRequestArgs(file, ranges);
+							}
+
+							return file;
+						}));
+				}
+				else {
+					requestFiles = allFiles;
+				}
+				request = client.executeAsync('geterr', { delay: 0, files: requestFiles }, this._token.token);
+			}
 
 			request.finally(() => {
 				if (this._done) {
@@ -350,6 +370,10 @@ class GetErrRequest {
 		return this.client.configuration.enableProjectDiagnostics && this.client.capabilities.has(ClientCapability.Semantic);
 	}
 
+	private areRegionDiagnosticsEnabled() {
+		return this.client.configuration.enableRegionDiagnostics && this.client.apiVersion.gte(API.v560);
+	}
+
 	public cancel(): any {
 		if (!this._done) {
 			this._token.cancel();
@@ -722,7 +746,9 @@ export default class BufferSyncSupport extends Disposable {
 
 		// Add all open TS buffers to the geterr request. They might be visible
 		for (const buffer of this.syncedBuffers.values()) {
-			orderedFileSet.set(buffer.resource, undefined);
+			const editors = vscode.window.visibleTextEditors.filter(editor => editor.document.uri.toString() === buffer.resource.toString());
+			const visibleRanges = editors.flatMap(editor => editor.visibleRanges);
+			orderedFileSet.set(buffer.resource, visibleRanges.length ? visibleRanges : undefined);
 		}
 
 		for (const { resource } of orderedFileSet.entries()) {

extensions/typescript-language-features/src/tsServer/protocol/protocol.const.ts

@@ -78,6 +78,7 @@ export enum EventName {
 	syntaxDiag = 'syntaxDiag',
 	semanticDiag = 'semanticDiag',
 	suggestionDiag = 'suggestionDiag',
+	regionSemanticDiag = 'regionSemanticDiag',
 	configFileDiag = 'configFileDiag',
 	telemetry = 'telemetry',
 	projectLanguageServiceState = 'projectLanguageServiceState',

extensions/typescript-language-features/src/typeConverters.ts

@@ -26,14 +26,24 @@ export namespace Range {
 			Math.max(0, start.line - 1), Math.max(start.offset - 1, 0),
 			Math.max(0, end.line - 1), Math.max(0, end.offset - 1));
 
-	export const toFileRangeRequestArgs = (file: string, range: vscode.Range): Proto.FileRangeRequestArgs => ({
-		file,
+	// @ts-expect-error until ts 5.6
+	export const toFileRange = (range: vscode.Range): Proto.FileRange => ({
 		startLine: range.start.line + 1,
 		startOffset: range.start.character + 1,
 		endLine: range.end.line + 1,
 		endOffset: range.end.character + 1
 	});
 
+	export const toFileRangeRequestArgs = (file: string, range: vscode.Range): Proto.FileRangeRequestArgs => ({
+		file,
+		...toFileRange(range)
+	});
+	// @ts-expect-error until ts 5.6
+	export const toFileRangesRequestArgs = (file: string, ranges: vscode.Range[]): Proto.FileRangesRequestArgs => ({
+		file,
+		ranges: ranges.map(toFileRange)
+	});
+
 	export const toFormattingRequestArgs = (file: string, range: vscode.Range): Proto.FormatRequestArgs => ({
 		file,
 		line: range.start.line + 1,

extensions/typescript-language-features/src/typeScriptServiceClientHost.ts

@@ -90,8 +90,8 @@ export default class TypeScriptServiceClientHost extends Disposable {
 			services,
 			allModeIds));
 
-		this.client.onDiagnosticsReceived(({ kind, resource, diagnostics }) => {
-			this.diagnosticsReceived(kind, resource, diagnostics);
+		this.client.onDiagnosticsReceived(({ kind, resource, diagnostics, spans }) => {
+			this.diagnosticsReceived(kind, resource, diagnostics, spans);
 		}, null, this._disposables);
 
 		this.client.onConfigDiagnosticsReceived(diag => this.configFileDiagnosticsReceived(diag), null, this._disposables);
@@ -236,14 +236,16 @@ export default class TypeScriptServiceClientHost extends Disposable {
 	private async diagnosticsReceived(
 		kind: DiagnosticKind,
 		resource: vscode.Uri,
-		diagnostics: Proto.Diagnostic[]
+		diagnostics: Proto.Diagnostic[],
+		spans: Proto.TextSpan[] | undefined,
 	): Promise<void> {
 		const language = await this.findLanguage(resource);
 		if (language) {
 			language.diagnosticsReceived(
 				kind,
 				resource,
-				this.createMarkerDatas(diagnostics, language.diagnosticSource));
+				this.createMarkerDatas(diagnostics, language.diagnosticSource),
+				spans?.map(span => typeConverters.Range.fromTextSpan(span)));
 		}
 	}
 

extensions/typescript-language-features/src/typescriptServiceClient.ts

@@ -37,6 +37,7 @@ export interface TsDiagnostics {
 	readonly kind: DiagnosticKind;
 	readonly resource: vscode.Uri;
 	readonly diagnostics: Proto.Diagnostic[];
+	readonly spans?: Proto.TextSpan[];
 }
 
 interface ToCancelOnResourceChanged {
@@ -947,7 +948,8 @@ export default class TypeScriptServiceClient extends Disposable implements IType
 		switch (event.event) {
 			case EventName.syntaxDiag:
 			case EventName.semanticDiag:
-			case EventName.suggestionDiag: {
+			case EventName.suggestionDiag:
+			case EventName.regionSemanticDiag: {
 				// This event also roughly signals that projects have been loaded successfully (since the TS server is synchronous)
 				this.loadingIndicator.reset();
 
@@ -956,7 +958,9 @@ export default class TypeScriptServiceClient extends Disposable implements IType
 					this._onDiagnosticsReceived.fire({
 						kind: getDiagnosticsKind(event),
 						resource: this.toResource(diagnosticEvent.body.file),
-						diagnostics: diagnosticEvent.body.diagnostics
+						diagnostics: diagnosticEvent.body.diagnostics,
+						// @ts-expect-error until ts 5.6
+						spans: diagnosticEvent.body.spans,
 					});
 				}
 				break;
@@ -1261,6 +1265,7 @@ function getDiagnosticsKind(event: Proto.Event) {
 		case 'syntaxDiag': return DiagnosticKind.Syntax;
 		case 'semanticDiag': return DiagnosticKind.Semantic;
 		case 'suggestionDiag': return DiagnosticKind.Suggestion;
+		case 'regionSemanticDiag': return DiagnosticKind.RegionSemantic;
 	}
 	throw new Error('Unknown dignostics kind');
 }