src/vs/editor/contrib/snippet/browser/snippetParser.ts/SnippetParser/ensureFinalTabstop
class SnippetParser:	ensureFinalTabstop(snippet: TextmateSnippet, enforceFinalTabstop: boolean, insertFinalTabstop: boolean) {

		if (enforceFinalTabstop || insertFinalTabstop && snippet.placeholders.length > 0) {
			const finalTabstop = snippet.placeholders.find(p => p.index === 0);
			if (!finalTabstop) {
				// the snippet uses placeholders but has no
				// final tabstop defined -> insert at the end
				snippet.appendChild(new Placeholder(0));
			}
		}

	}