feat(switchMap): removed deprecated switchMap(project, resultSelector…

…) call pattern BREAKING CHANGE: `switchMap(project, resultSelector)` call pattern is no longer available. [Read more](https://rxjs.dev/deprecations/resultSelector).
ReactiveX · Oct 30, 2022 · ff3a705 · ff3a705
1 parent 2c6da12
commit ff3a705
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Showing 5 changed files with 12 additions and 113 deletions.
diff --git a/api_guard/dist/types/index.d.ts b/api_guard/dist/types/index.d.ts
@@ -672,8 +672,6 @@ export interface SubscriptionLike extends Unsubscribable {
 export declare function switchAll<O extends ObservableInput<any>>(): OperatorFunction<O, ObservedValueOf<O>>;
 
 export declare function switchMap<T, O extends ObservableInput<any>>(project: (value: T, index: number) => O): OperatorFunction<T, ObservedValueOf<O>>;
-export declare function switchMap<T, O extends ObservableInput<any>>(project: (value: T, index: number) => O, resultSelector: undefined): OperatorFunction<T, ObservedValueOf<O>>;
-export declare function switchMap<T, R, O extends ObservableInput<any>>(project: (value: T, index: number) => O, resultSelector: (outerValue: T, innerValue: ObservedValueOf<O>, outerIndex: number, innerIndex: number) => R): OperatorFunction<T, R>;
 
 export declare function switchMapTo<O extends ObservableInput<unknown>>(innerObservable: O): OperatorFunction<unknown, ObservedValueOf<O>>;
 

diff --git a/api_guard/dist/types/operators/index.d.ts b/api_guard/dist/types/operators/index.d.ts
@@ -288,8 +288,6 @@ export declare function subscribeOn<T>(scheduler: SchedulerLike, delay?: number)
 export declare function switchAll<O extends ObservableInput<any>>(): OperatorFunction<O, ObservedValueOf<O>>;
 
 export declare function switchMap<T, O extends ObservableInput<any>>(project: (value: T, index: number) => O): OperatorFunction<T, ObservedValueOf<O>>;
-export declare function switchMap<T, O extends ObservableInput<any>>(project: (value: T, index: number) => O, resultSelector: undefined): OperatorFunction<T, ObservedValueOf<O>>;
-export declare function switchMap<T, R, O extends ObservableInput<any>>(project: (value: T, index: number) => O, resultSelector: (outerValue: T, innerValue: ObservedValueOf<O>, outerIndex: number, innerIndex: number) => R): OperatorFunction<T, R>;
 
 export declare function switchMapTo<O extends ObservableInput<unknown>>(innerObservable: O): OperatorFunction<unknown, ObservedValueOf<O>>;
 

diff --git a/spec-dtslint/operators/switchMap-spec.ts b/spec-dtslint/operators/switchMap-spec.ts
@@ -9,26 +9,6 @@ it('should support a projector that takes an index', () => {
   const o = of(1, 2, 3).pipe(switchMap(p => of(Boolean(p)))); // $ExpectType Observable<boolean>
 });
 
-it('should infer correctly by using the resultSelector first parameter', () => {
-  const o = of(1, 2, 3).pipe(switchMap(p => of(Boolean(p)), a => a)); // $ExpectType Observable<number>
-});
-
-it('should infer correctly by using the resultSelector second parameter', () => {
-  const o = of(1, 2, 3).pipe(switchMap(p => of(Boolean(p)), (a, b) => b)); // $ExpectType Observable<boolean>
-});
-
-it('should support a resultSelector that takes an inner index', () => {
-  const o = of(1, 2, 3).pipe(switchMap(p => of(Boolean(p)), (a, b, i) => a)); // $ExpectType Observable<number>
-});
-
-it('should support a resultSelector that takes an inner and outer index', () => {
-  const o = of(1, 2, 3).pipe(switchMap(p => of(Boolean(p)), (a, b, i, ii) => a)); // $ExpectType Observable<number>
-});
-
-it('should support an undefined resultSelector', () => {
-  const o = of(1, 2, 3).pipe(switchMap(p => of(Boolean(p)), undefined)); // $ExpectType Observable<boolean>
-});
-
 it('should support union-type projections with empty streams', () => {
   const o = of(1, 2, 3).pipe(switchMap(n => Math.random() < 0.5 ? of(123) : of())); // $ExpectType Observable<number>
 });

diff --git a/spec/operators/switchMap-spec.ts b/spec/operators/switchMap-spec.ts
@@ -30,57 +30,6 @@ describe('switchMap', () => {
     });
   });
 
-  it('should support the deprecated resultSelector', () => {
-    const results: Array<number[]> = [];
-
-    of(1, 2, 3)
-      .pipe(
-        switchMap(
-          (x) => of(x, x + 1, x + 2),
-          (a, b, i, ii) => [a, b, i, ii]
-        )
-      )
-      .subscribe({
-        next(value) {
-          results.push(value);
-        },
-        error(err) {
-          throw err;
-        },
-        complete() {
-          expect(results).to.deep.equal([
-            [1, 1, 0, 0],
-            [1, 2, 0, 1],
-            [1, 3, 0, 2],
-            [2, 2, 1, 0],
-            [2, 3, 1, 1],
-            [2, 4, 1, 2],
-            [3, 3, 2, 0],
-            [3, 4, 2, 1],
-            [3, 5, 2, 2],
-          ]);
-        },
-      });
-  });
-
-  it('should support a void resultSelector (still deprecated)', () => {
-    const results: number[] = [];
-
-    of(1, 2, 3)
-      .pipe(switchMap((x) => of(x, x + 1, x + 2), void 0))
-      .subscribe({
-        next(value) {
-          results.push(value);
-        },
-        error(err) {
-          throw err;
-        },
-        complete() {
-          expect(results).to.deep.equal([1, 2, 3, 2, 3, 4, 3, 4, 5]);
-        },
-      });
-  });
-
   it('should unsub inner observables', () => {
     const unsubbed: string[] = [];
 

diff --git a/src/internal/operators/switchMap.ts b/src/internal/operators/switchMap.ts
@@ -4,22 +4,6 @@ import { innerFrom } from '../observable/innerFrom';
 import { operate } from '../util/lift';
 import { createOperatorSubscriber } from './OperatorSubscriber';
 
-/* tslint:disable:max-line-length */
-export function switchMap<T, O extends ObservableInput<any>>(
-  project: (value: T, index: number) => O
-): OperatorFunction<T, ObservedValueOf<O>>;
-/** @deprecated The `resultSelector` parameter will be removed in v8. Use an inner `map` instead. Details: https://rxjs.dev/deprecations/resultSelector */
-export function switchMap<T, O extends ObservableInput<any>>(
-  project: (value: T, index: number) => O,
-  resultSelector: undefined
-): OperatorFunction<T, ObservedValueOf<O>>;
-/** @deprecated The `resultSelector` parameter will be removed in v8. Use an inner `map` instead. Details: https://rxjs.dev/deprecations/resultSelector */
-export function switchMap<T, R, O extends ObservableInput<any>>(
-  project: (value: T, index: number) => O,
-  resultSelector: (outerValue: T, innerValue: ObservedValueOf<O>, outerIndex: number, innerIndex: number) => R
-): OperatorFunction<T, R>;
-/* tslint:enable:max-line-length */
-
 /**
  * Projects each source value to an Observable which is merged in the output
  * Observable, emitting values only from the most recently projected Observable.
@@ -79,14 +63,12 @@ export function switchMap<T, R, O extends ObservableInput<any>>(
  * that, when applied to an item emitted by the source Observable, returns an
  * Observable.
  * @return A function that returns an Observable that emits the result of
- * applying the projection function (and the optional deprecated
- * `resultSelector`) to each item emitted by the source Observable and taking
- * only the values from the most recently projected inner Observable.
+ * applying the projection function to each item emitted by the source Observable
+ * and taking only the values from the most recently projected inner Observable.
  */
-export function switchMap<T, R, O extends ObservableInput<any>>(
-  project: (value: T, index: number) => O,
-  resultSelector?: (outerValue: T, innerValue: ObservedValueOf<O>, outerIndex: number, innerIndex: number) => R
-): OperatorFunction<T, ObservedValueOf<O> | R> {
+export function switchMap<T, O extends ObservableInput<any>>(
+  project: (value: T, index: number) => O
+): OperatorFunction<T, ObservedValueOf<O>> {
   return operate((source, subscriber) => {
     let innerSubscriber: Subscriber<ObservedValueOf<O>> | null = null;
     let index = 0;
@@ -103,24 +85,16 @@ export function switchMap<T, R, O extends ObservableInput<any>>(
         (value) => {
           // Cancel the previous inner subscription if there was one
           innerSubscriber?.unsubscribe();
-          let innerIndex = 0;
           const outerIndex = index++;
           // Start the next inner subscription
           innerFrom(project(value, outerIndex)).subscribe(
-            (innerSubscriber = createOperatorSubscriber(
-              subscriber,
-              // When we get a new inner value, next it through. Note that this is
-              // handling the deprecate result selector here. This is because with this architecture
-              // it ends up being smaller than using the map operator.
-              (innerValue) => subscriber.next(resultSelector ? resultSelector(value, innerValue, outerIndex, innerIndex++) : innerValue),
-              () => {
-                // The inner has completed. Null out the inner subscriber to
-                // free up memory and to signal that we have no inner subscription
-                // currently.
-                innerSubscriber = null!;
-                checkComplete();
-              }
-            ))
+            (innerSubscriber = createOperatorSubscriber(subscriber, undefined, () => {
+              // The inner has completed. Null out the inner subscriber to
+              // free up memory and to signal that we have no inner subscription
+              // currently.
+              innerSubscriber = null!;
+              checkComplete();
+            }))
           );
         },
         () => {