fix: forkJoin/combineLatest return Observable<unknown> if passed any

api_guard/dist/types/index.d.ts

@@ -52,6 +52,7 @@ export declare function combineLatest<A extends readonly unknown[]>(...sourcesAn
 export declare function combineLatest(sourcesObject: {
     [K in any]: never;
 }): Observable<never>;
+export declare function combineLatest<T extends AnyCatcher>(arg: T): Observable<unknown>;
 export declare function combineLatest<T extends Record<string, ObservableInput<any>>>(sourcesObject: T): Observable<{
     [K in keyof T]: ObservedValueOf<T[K]>;
 }>;
@@ -134,6 +135,7 @@ export declare function forkJoin<A extends readonly unknown[], R>(...sourcesAndR
 export declare function forkJoin(sourcesObject: {
     [K in any]: never;
 }): Observable<never>;
+export declare function forkJoin<T extends AnyCatcher>(arg: T): Observable<unknown>;
 export declare function forkJoin<T extends Record<string, ObservableInput<any>>>(sourcesObject: T): Observable<{
     [K in keyof T]: ObservedValueOf<T[K]>;
 }>;

spec-dtslint/observables/combineLatest-spec.ts

@@ -147,3 +147,8 @@ describe('combineLatest({})', () => {
     const res = combineLatest(obj); // $ExpectError
   });
 });
+
+it('should take in any and return Observable<unknown> because we do not know if it is an array or object', () => {
+  const arg: any = null;
+  const res = combineLatest(arg); // $ExpectType Observable<unknown>
+});

spec-dtslint/observables/forkJoin-spec.ts

@@ -117,4 +117,9 @@ describe('forkJoin([])', () => {
   it('should force user cast for array of 6+ observables', () => {
     const res = forkJoin([of(1, 2, 3), of('a', 'b', 'c'), of(1, 2, 3), of(1, 2, 3), of(1, 2, 3), of(1, 2, 3), of(1, 2, 3)]); // $ExpectType Observable<[number, string, number, number, number, number, number]>
   });
+
+  it('should return unknown for argument of any', () => {
+    const arg: any = null;
+    const res = forkJoin(arg); // $ExpectType Observable<unknown>
+  })
 });

src/internal/AnyCatcher.ts

@@ -0,0 +1,11 @@
+/**
+ * This is just a type that we're using to identify `any` being passed to
+ * function overloads. This is used because of situations like {@link forkJoin},
+ * where it could return an `Observable<T[]>` or an `Observable<{ [key: K]: T }>`,
+ * so `forkJoin(any)` would mean we need to return `Observable<unknown>`.
+ *
+ * @internal
+ */
+export interface AnyCatcher {
+  readonly ' @@@@@@CATCH_ANY_WITH_THIS@@@@@@': false;
+}

src/internal/observable/combineLatest.ts

@@ -9,6 +9,7 @@ import { mapOneOrManyArgs } from '../util/mapOneOrManyArgs';
 import { popResultSelector, popScheduler } from '../util/args';
 import { createObject } from '../util/createObject';
 import { OperatorSubscriber } from '../operators/OperatorSubscriber';
+import { AnyCatcher } from '../AnyCatcher';
 
 // combineLatest([a, b, c])
 export function combineLatest(sources: []): Observable<never>;
@@ -47,6 +48,12 @@ export function combineLatest<A extends readonly unknown[]>(
 
 // combineLatest({a, b, c})
 export function combineLatest(sourcesObject: { [K in any]: never }): Observable<never>;
+/**
+ * You have passed `any` here, we can't figure out if it is
+ * an array or an object, so you're getting `unknown`. Use better types.
+ * @param arg Something typed as `any`
+ */
+export function combineLatest<T extends AnyCatcher>(arg: T): Observable<unknown>;
 export function combineLatest<T extends Record<string, ObservableInput<any>>>(
   sourcesObject: T
 ): Observable<{ [K in keyof T]: ObservedValueOf<T[K]> }>;

src/internal/observable/forkJoin.ts

@@ -6,6 +6,7 @@ import { popResultSelector } from '../util/args';
 import { OperatorSubscriber } from '../operators/OperatorSubscriber';
 import { mapOneOrManyArgs } from '../util/mapOneOrManyArgs';
 import { createObject } from '../util/createObject';
+import { AnyCatcher } from '../AnyCatcher';
 
 export function forkJoin(scheduler: null | undefined): Observable<never>;
 
@@ -27,6 +28,12 @@ export function forkJoin<A extends readonly unknown[], R>(
 
 // forkJoin({a, b, c})
 export function forkJoin(sourcesObject: { [K in any]: never }): Observable<never>;
+/**
+ * You have passed `any` here, we can't figure out if it is
+ * an array or an object, so you're getting `unknown`. Use better types.
+ * @param arg Something typed as `any`
+ */
+export function forkJoin<T extends AnyCatcher>(arg: T): Observable<unknown>;
 export function forkJoin<T extends Record<string, ObservableInput<any>>>(
   sourcesObject: T
 ): Observable<{ [K in keyof T]: ObservedValueOf<T[K]> }>;