From 27de080148d55d012a37d04078f2e15d90ed0b07 Mon Sep 17 00:00:00 2001
From: OJ Kwon <kwon.ohjoong@gmail.com>
Date: Thu, 3 Dec 2015 14:10:48 -0800
Subject: [PATCH] feat(takeWhile): remove thisArg

relates to #878
---
 spec/operators/takeWhile-spec.js | 17 -----------------
 src/CoreOperators.ts             |  2 +-
 src/Observable.ts                |  2 +-
 src/operator/takeWhile.ts        | 18 +++++-------------
 4 files changed, 7 insertions(+), 32 deletions(-)

diff --git a/spec/operators/takeWhile-spec.js b/spec/operators/takeWhile-spec.js
index 179c8e42e0..a538e56713 100644
--- a/spec/operators/takeWhile-spec.js
+++ b/spec/operators/takeWhile-spec.js
@@ -154,23 +154,6 @@ describe('Observable.prototype.takeWhile()', function () {
     expectSubscriptions(e1.subscriptions).toBe(e1subs);
   });
 
-  it('should pass element thisArg to predicate', function () {
-    var e1 = hot('--a-^-b--c--d--e--|');
-    var e1subs =     '^       !      ';
-    var expected =   '--b--c--|      ';
-
-    function predicate() {
-      this.take = function (value) {
-        return value !== 'd';
-      };
-    }
-
-    var result = e1.takeWhile(function (v) { return this.take(v); }, new predicate());
-
-    expectObservable(result).toBe(expected);
-    expectSubscriptions(e1.subscriptions).toBe(e1subs);
-  });
-
   it('should take elements until unsubscribed', function () {
     var e1 = hot('--a-^-b--c--d--e--|');
     var unsub =      '-----!         ';
diff --git a/src/CoreOperators.ts b/src/CoreOperators.ts
index 986c42c187..c23c6a55cd 100644
--- a/src/CoreOperators.ts
+++ b/src/CoreOperators.ts
@@ -77,7 +77,7 @@ export interface CoreOperators<T> {
   switchMapTo?: <R>(observable: Observable<any>, projectResult?: (x: T, y: any, ix: number, iy: number) => R) => Observable<R>;
   take?: (count: number) => Observable<T>;
   takeUntil?: (notifier: Observable<any>) => Observable<T>;
-  takeWhile?: (predicate: (value: T, index: number) => boolean, thisArg?: any) => Observable<T>;
+  takeWhile?: (predicate: (value: T, index: number) => boolean) => Observable<T>;
   throttle?: (durationSelector: (value: T) => Observable<any> | Promise<any>) => Observable<T>;
   throttleTime?: (delay: number, scheduler?: Scheduler) => Observable<T>;
   timeout?: (due: number | Date, errorToSend?: any, scheduler?: Scheduler) => Observable<T>;
diff --git a/src/Observable.ts b/src/Observable.ts
index 7aa132d93f..8f37a028a9 100644
--- a/src/Observable.ts
+++ b/src/Observable.ts
@@ -239,7 +239,7 @@ export class Observable<T> implements CoreOperators<T>  {
   switchMapTo: <R>(observable: Observable<any>, projectResult?: (x: T, y: any, ix: number, iy: number) => R) => Observable<R>;
   take: (count: number) => Observable<T>;
   takeUntil: (notifier: Observable<any>) => Observable<T>;
-  takeWhile: (predicate: (value: T, index: number) => boolean, thisArg?: any) => Observable<T>;
+  takeWhile: (predicate: (value: T, index: number) => boolean) => Observable<T>;
   throttle: (durationSelector: (value: T) => Observable<any> | Promise<any>) => Observable<T>;
   throttleTime: (delay: number, scheduler?: Scheduler) => Observable<T>;
   timeout: (due: number | Date, errorToSend?: any, scheduler?: Scheduler) => Observable<T>;
diff --git a/src/operator/takeWhile.ts b/src/operator/takeWhile.ts
index 0af0ab5a11..53b4060681 100644
--- a/src/operator/takeWhile.ts
+++ b/src/operator/takeWhile.ts
@@ -3,34 +3,26 @@ import {Observable} from '../Observable';
 import {Subscriber} from '../Subscriber';
 import {tryCatch} from '../util/tryCatch';
 import {errorObject} from '../util/errorObject';
-import {bindCallback} from '../util/bindCallback';
 
-export function takeWhile<T>(predicate: (value: T, index: number) => boolean,
-                             thisArg?: any): Observable<T> {
-  return this.lift(new TakeWhileOperator(predicate, thisArg));
+export function takeWhile<T>(predicate: (value: T, index: number) => boolean): Observable<T> {
+  return this.lift(new TakeWhileOperator(predicate));
 }
 
 class TakeWhileOperator<T, R> implements Operator<T, R> {
-  constructor(private predicate: (value: T, index: number) => boolean,
-              private thisArg?: any) {
+  constructor(private predicate: (value: T, index: number) => boolean) {
   }
 
   call(subscriber: Subscriber<T>): Subscriber<T> {
-    return new TakeWhileSubscriber(subscriber, this.predicate, this.thisArg);
+    return new TakeWhileSubscriber(subscriber, this.predicate);
   }
 }
 
 class TakeWhileSubscriber<T> extends Subscriber<T> {
-  private predicate: (value: T, index: number) => boolean;
   private index: number = 0;
 
   constructor(destination: Subscriber<T>,
-              predicate: (value: T, index: number) => boolean,
-              thisArg?: any) {
+              private predicate: (value: T, index: number) => boolean) {
     super(destination);
-    if (typeof predicate === 'function') {
-      this.predicate = <(value: T, index: number) => boolean>bindCallback(predicate, thisArg, 2);
-    }
   }
 
   _next(value: T): void {