From f0395836b67a8d95223a8f63a9d423171f8ea1e8 Mon Sep 17 00:00:00 2001
From: Matt Lewis <hello@mattlewis.me>
Date: Wed, 29 May 2019 16:39:27 -0400
Subject: [PATCH] fix(ivy): evaluate non existing property access as undefined
 (#30738)

Closes #30726

PR Close #30738
---
 .../src/ngtsc/partial_evaluator/src/interpreter.ts             | 2 +-
 .../src/ngtsc/partial_evaluator/test/evaluator_spec.ts         | 3 +++
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/packages/compiler-cli/src/ngtsc/partial_evaluator/src/interpreter.ts b/packages/compiler-cli/src/ngtsc/partial_evaluator/src/interpreter.ts
index a74c84770e..07d0f6452b 100644
--- a/packages/compiler-cli/src/ngtsc/partial_evaluator/src/interpreter.ts
+++ b/packages/compiler-cli/src/ngtsc/partial_evaluator/src/interpreter.ts
@@ -329,7 +329,7 @@ export class StaticInterpreter {
       if (lhs.has(strIndex)) {
         return lhs.get(strIndex) !;
       } else {
-        throw new Error(`Invalid map access: [${Array.from(lhs.keys())}] dot ${rhs}`);
+        return undefined;
       }
     } else if (Array.isArray(lhs)) {
       if (rhs === 'length') {
diff --git a/packages/compiler-cli/src/ngtsc/partial_evaluator/test/evaluator_spec.ts b/packages/compiler-cli/src/ngtsc/partial_evaluator/test/evaluator_spec.ts
index f6ff0a83c0..3c1ab32600 100644
--- a/packages/compiler-cli/src/ngtsc/partial_evaluator/test/evaluator_spec.ts
+++ b/packages/compiler-cli/src/ngtsc/partial_evaluator/test/evaluator_spec.ts
@@ -39,6 +39,9 @@ describe('ngtsc metadata', () => {
   it('map access works',
      () => { expect(evaluate('const obj = {a: "test"};', 'obj.a')).toEqual('test'); });
 
+  it('resolves undefined property access',
+     () => { expect(evaluate('const obj: any = {}', 'obj.bar')).toEqual(undefined); });
+
   it('function calls work', () => {
     expect(evaluate(`function foo(bar) { return bar; }`, 'foo("test")')).toEqual('test');
   });