src/vs/editor/contrib/suggest/suggest.ts/snippetUpComparator
function snippetUpComparator(a: CompletionItem, b: CompletionItem): number {
	if (a.completion.kind !== b.completion.kind) {
		if (a.completion.kind === modes.CompletionItemKind.Snippet) {
			return -1;
		} else if (b.completion.kind === modes.CompletionItemKind.Snippet) {
			return 1;
		}
	}
	return defaultComparator(a, b);
}