Initial commit: Aeroflot Flights Web Angular 12 application

ClientApp/src/polyfills/array.extensions.ts

@@ -0,0 +1,34 @@
+export type Group<T, TK> = { key: TK; items: T[] };
+
+declare global {
+    interface Array<T> {
+        groupBy<T, TK>(keyFn: (item: T) => TK): Group<T, TK>[];
+        intersect<T>(other: T[]): T[];
+    }
+}
+
+if (!Array.prototype.groupBy)
+    Array.prototype.intersect = function <T>(this: T[], other: T[]): T[] {
+        const set = new Set<T>(this);
+        return other.filter((i) => set.has(i));
+    };
+if (!Array.prototype.groupBy)
+    Array.prototype.groupBy = function <T, TK>(
+        this: T[],
+        keyFn: (item: T) => TK,
+    ): Group<T, TK>[] {
+        const hash = new Map<TK, Group<T, TK>>();
+
+        this.forEach((item) => {
+            const key = keyFn(item);
+            let group = hash.get(key);
+            if (!group) {
+                group = { key, items: [] };
+                hash.set(key, group);
+            }
+            group.items.push(item);
+        });
+
+        return [...hash.values()];
+    };
+export default {};