Fix EsLint Brackets (error markup 'const').

node_modules/rxjs/src/internal/operators/debounce.ts

@@ -0,0 +1,145 @@
+import { Operator } from '../Operator';
+import { Observable } from '../Observable';
+import { Subscriber } from '../Subscriber';
+import { Subscription } from '../Subscription';
+import { MonoTypeOperatorFunction, SubscribableOrPromise, TeardownLogic } from '../types';
+
+import { OuterSubscriber } from '../OuterSubscriber';
+import { InnerSubscriber } from '../InnerSubscriber';
+import { subscribeToResult } from '../util/subscribeToResult';
+
+/**
+ * Emits a value from the source Observable only after a particular time span
+ * determined by another Observable has passed without another source emission.
+ *
+ * <span class="informal">It's like {@link debounceTime}, but the time span of
+ * emission silence is determined by a second Observable.</span>
+ *
+ * ![](debounce.png)
+ *
+ * `debounce` delays values emitted by the source Observable, but drops previous
+ * pending delayed emissions if a new value arrives on the source Observable.
+ * This operator keeps track of the most recent value from the source
+ * Observable, and spawns a duration Observable by calling the
+ * `durationSelector` function. The value is emitted only when the duration
+ * Observable emits a value or completes, and if no other value was emitted on
+ * the source Observable since the duration Observable was spawned. If a new
+ * value appears before the duration Observable emits, the previous value will
+ * be dropped and will not be emitted on the output Observable.
+ *
+ * Like {@link debounceTime}, this is a rate-limiting operator, and also a
+ * delay-like operator since output emissions do not necessarily occur at the
+ * same time as they did on the source Observable.
+ *
+ * ## Example
+ * Emit the most recent click after a burst of clicks
+ * ```javascript
+ * const clicks = fromEvent(document, 'click');
+ * const result = clicks.pipe(debounce(() => interval(1000)));
+ * result.subscribe(x => console.log(x));
+ * ```
+ *
+ * @see {@link audit}
+ * @see {@link debounceTime}
+ * @see {@link delayWhen}
+ * @see {@link throttle}
+ *
+ * @param {function(value: T): SubscribableOrPromise} durationSelector A function
+ * that receives a value from the source Observable, for computing the timeout
+ * duration for each source value, returned as an Observable or a Promise.
+ * @return {Observable} An Observable that delays the emissions of the source
+ * Observable by the specified duration Observable returned by
+ * `durationSelector`, and may drop some values if they occur too frequently.
+ * @method debounce
+ * @owner Observable
+ */
+export function debounce<T>(durationSelector: (value: T) => SubscribableOrPromise<any>): MonoTypeOperatorFunction<T> {
+  return (source: Observable<T>) => source.lift(new DebounceOperator(durationSelector));
+}
+
+class DebounceOperator<T> implements Operator<T, T> {
+  constructor(private durationSelector: (value: T) => SubscribableOrPromise<any>) {
+  }
+
+  call(subscriber: Subscriber<T>, source: any): TeardownLogic {
+    return source.subscribe(new DebounceSubscriber(subscriber, this.durationSelector));
+  }
+}
+
+/**
+ * We need this JSDoc comment for affecting ESDoc.
+ * @ignore
+ * @extends {Ignored}
+ */
+class DebounceSubscriber<T, R> extends OuterSubscriber<T, R> {
+  private value: T;
+  private hasValue: boolean = false;
+  private durationSubscription: Subscription = null;
+
+  constructor(destination: Subscriber<R>,
+              private durationSelector: (value: T) => SubscribableOrPromise<any>) {
+    super(destination);
+  }
+
+  protected _next(value: T): void {
+    try {
+      const result = this.durationSelector.call(this, value);
+
+      if (result) {
+        this._tryNext(value, result);
+      }
+    } catch (err) {
+      this.destination.error(err);
+    }
+  }
+
+  protected _complete(): void {
+    this.emitValue();
+    this.destination.complete();
+  }
+
+  private _tryNext(value: T, duration: SubscribableOrPromise<any>): void {
+    let subscription = this.durationSubscription;
+    this.value = value;
+    this.hasValue = true;
+    if (subscription) {
+      subscription.unsubscribe();
+      this.remove(subscription);
+    }
+
+    subscription = subscribeToResult(this, duration);
+    if (subscription && !subscription.closed) {
+      this.add(this.durationSubscription = subscription);
+    }
+  }
+
+  notifyNext(outerValue: T, innerValue: R,
+             outerIndex: number, innerIndex: number,
+             innerSub: InnerSubscriber<T, R>): void {
+    this.emitValue();
+  }
+
+  notifyComplete(): void {
+    this.emitValue();
+  }
+
+  emitValue(): void {
+    if (this.hasValue) {
+      const value = this.value;
+      const subscription = this.durationSubscription;
+      if (subscription) {
+        this.durationSubscription = null;
+        subscription.unsubscribe();
+        this.remove(subscription);
+      }
+      // This must be done *before* passing the value
+      // along to the destination because it's possible for
+      // the value to synchronously re-enter this operator
+      // recursively if the duration selector Observable
+      // emits synchronously
+      this.value = null;
+      this.hasValue = false;
+      super._next(value);
+    }
+  }
+}