From 1c04b3494bb009064725c3977435e3172ccdf3eb Mon Sep 17 00:00:00 2001
From: Josep M Sobrepere <josepot@gmail.com>
Date: Sun, 23 Aug 2020 08:27:50 +0200
Subject: [PATCH] refactor(catchError): simplify implementation

---
 src/internal/operators/catchError.ts | 42 ++++------------------------
 1 file changed, 6 insertions(+), 36 deletions(-)

diff --git a/src/internal/operators/catchError.ts b/src/internal/operators/catchError.ts
index f793d1b3de9..c4dcf76cc91 100644
--- a/src/internal/operators/catchError.ts
+++ b/src/internal/operators/catchError.ts
@@ -110,45 +110,15 @@ export function catchError<T, O extends ObservableInput<any>>(
 ): OperatorFunction<T, T | ObservedValueOf<O>> {
   return (source: Observable<T>) =>
     lift(source, function (this: Subscriber<T>, source: Observable<T>) {
-      const subscriber = this;
-      const subscription = new Subscription();
-      let innerSub: Subscription | null = null;
-      let syncUnsub = false;
-      let handledResult: Observable<ObservedValueOf<O>>;
-
-      const handleError = (err: any) => {
-        try {
-          handledResult = from(selector(err, catchError(selector)(source)));
-        } catch (err) {
-          subscriber.error(err);
-          return;
-        }
-      };
-
-      innerSub = source.subscribe(
-        new CatchErrorSubscriber(subscriber, (err) => {
-          handleError(err);
-          if (handledResult) {
-            if (innerSub) {
-              innerSub.unsubscribe();
-              innerSub = null;
-              subscription.add(handledResult.subscribe(subscriber));
-            } else {
-              syncUnsub = true;
-            }
+      source.subscribe(
+        new CatchErrorSubscriber(this, (err) => {
+          try {
+            from(selector(err, catchError(selector)(source))).subscribe(this);
+          } catch (selectorErr) {
+            this.error(selectorErr);
           }
         })
       );
-
-      if (syncUnsub) {
-        innerSub.unsubscribe();
-        innerSub = null;
-        subscription.add(handledResult!.subscribe(subscriber));
-      } else {
-        subscription.add(innerSub);
-      }
-
-      return subscription;
     });
 }