From 3bb2f7fe4cfb42695cbfac4cfaa15b72708963a1 Mon Sep 17 00:00:00 2001
From: Anirudh Varma <varma93@hotmail.com>
Date: Tue, 30 Jun 2020 02:07:49 +0530
Subject: [PATCH] fix(pluck): operator breaks with null/undefined inputs.
 (#5524)

* test(pluck): add failing test case for using null value.

* fix(pluck): check for null/undefined object before attempting to access prop

* Remove null coalescing when checking values to prevent null values being converted to undefined
---
 spec/operators/pluck-spec.ts    | 22 ++++++++++++++++++++++
 src/internal/operators/pluck.ts |  4 ++--
 2 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/spec/operators/pluck-spec.ts b/spec/operators/pluck-spec.ts
index 2d710a9264..71ad0bcdb6 100644
--- a/spec/operators/pluck-spec.ts
+++ b/spec/operators/pluck-spec.ts
@@ -176,4 +176,26 @@ describe('pluck operator', () => {
     expectObservable(r, unsub).toBe(expected);
     expectSubscriptions(a.subscriptions).toBe(asubs);
   });
+
+  it('should support symbols', () => {
+    const sym = Symbol('sym');
+
+    const a =   cold('--x--|', {x: {[sym]: 'abc'}});
+    const asubs =    '^    !';
+    const expected = '--y--|';
+
+    const r = a.pipe(pluck(sym));
+    expectObservable(r).toBe(expected, {y: 'abc'});
+    expectSubscriptions(a.subscriptions).toBe(asubs);
+  });
+
+  it('should not break on null values', () => {
+    const a =   cold('--x--|', {x: null});
+    const asubs =    '^    !';
+    const expected = '--y--|';
+
+    const r = a.pipe(pluck('prop'));
+    expectObservable(r).toBe(expected, {y: undefined});
+    expectSubscriptions(a.subscriptions).toBe(asubs);
+  });
 });
diff --git a/src/internal/operators/pluck.ts b/src/internal/operators/pluck.ts
index dbe050f25d..543f0d715a 100644
--- a/src/internal/operators/pluck.ts
+++ b/src/internal/operators/pluck.ts
@@ -56,8 +56,8 @@ function plucker(props: string[], length: number): (x: string) => any {
   const mapper = (x: string) => {
     let currentProp = x;
     for (let i = 0; i < length; i++) {
-      const p = currentProp[props[i]];
-      if (typeof p !== 'undefined') {
+      const p = currentProp != null ? currentProp[props[i]] : undefined;
+      if (p !== void 0) {
         currentProp = p;
       } else {
         return undefined;