remove lodash dependency

fixes #19438

extensions/git/src/util.ts

@@ -57,4 +57,35 @@ export function once<T>(event: Event<T>): Event<T> {
 
 export function eventToPromise<T>(event: Event<T>): Promise<T> {
 	return new Promise(c => once(event)(c));
+}
+
+export function assign<T>(destination: T, ...sources: any[]): T {
+	for (const source of sources) {
+		Object.keys(source).forEach(key => destination[key] = source[key]);
+	}
+
+	return destination;
+}
+
+export function uniqBy<T>(arr: T[], fn: (el: T) => string): T[] {
+	const seen = Object.create(null);
+
+	return arr.filter(el => {
+		const key = fn(el);
+
+		if (seen[key]) {
+			return false;
+		}
+
+		seen[key] = true;
+		return true;
+	});
+}
+
+export function groupBy<T>(arr: T[], fn: (el: T) => string): { [key: string]: T[] } {
+	return arr.reduce((result, el) => {
+		const key = fn(el);
+		result[key] = [...(result[key] || []), el];
+		return result;
+	}, Object.create(null));
 }