extensions/typescript-language-features/src/languageFeatures/diagnostics.ts/DiagnosticsManager/updateCurrentDiagnostics
class DiagnosticsManager:	private updateCurrentDiagnostics(file: vscode.Uri): void {
		if (this._pendingUpdates.has(file)) {
			clearTimeout(this._pendingUpdates.get(file));
			this._pendingUpdates.delete(file);
		}

		const fileDiagnostics = this._diagnostics.get(file);
		this._currentDiagnostics.set(file, fileDiagnostics ? fileDiagnostics.getDiagnostics(this._settings) : []);
	}