src/vs/workbench/api/browser/mainThreadEditors.ts/MainThreadTextEditors/$tryInsertSnippet
class MainThreadTextEditors:	$tryInsertSnippet(id: string, template: string, ranges: readonly IRange[], opts: IUndoStopOptions): Promise<boolean> {
		const editor = this._documentsAndEditors.getEditor(id);
		if (!editor) {
			return Promise.reject(disposed(`TextEditor(${id})`));
		}
		return Promise.resolve(editor.insertSnippet(template, ranges, opts));
	}