From 2d9111bfb698aa1e418cbd73b33e3ef73209084e Mon Sep 17 00:00:00 2001
From: JoostK <joost.koehoorn@gmail.com>
Date: Sun, 27 May 2018 15:26:41 +0200
Subject: [PATCH] fix(ivy): account for multiple changes between change
 detection runs (#24152)

PR Close #24152
---
 packages/core/src/render3/definition.ts   | 8 +++++++-
 packages/core/test/render3/define_spec.ts | 4 ++--
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/packages/core/src/render3/definition.ts b/packages/core/src/render3/definition.ts
index d17049868d..e39abdb9b7 100644
--- a/packages/core/src/render3/definition.ts
+++ b/packages/core/src/render3/definition.ts
@@ -272,7 +272,13 @@ export function NgOnChangesFeature(inputPropertyNames?: {[key: string]: string})
                 this, PRIVATE_PREFIX, {value: simpleChanges = {}, writable: true});
           }
           const isFirstChange = !this.hasOwnProperty(privateMinKey);
-          simpleChanges[propertyName] = new SimpleChange(this[privateMinKey], value, isFirstChange);
+          const currentChange: SimpleChange|undefined = simpleChanges[propertyName];
+          if (currentChange) {
+            currentChange.currentValue = value;
+          } else {
+            simpleChanges[propertyName] =
+                new SimpleChange(this[privateMinKey], value, isFirstChange);
+          }
           if (isFirstChange) {
             // Create a place where the actual value will be stored and make it non-enumerable
             Object.defineProperty(this, privateMinKey, {value, writable: true});
diff --git a/packages/core/test/render3/define_spec.ts b/packages/core/test/render3/define_spec.ts
index 2253dba899..6c9f6565e7 100644
--- a/packages/core/test/render3/define_spec.ts
+++ b/packages/core/test/render3/define_spec.ts
@@ -45,7 +45,7 @@ describe('define', () => {
         expect(myDir.valB).toEqual('works');
         myDir.log.length = 0;
         (MyDirective.ngDirectiveDef as DirectiveDef<MyDirective>).doCheck !.call(myDir);
-        const changeA = new SimpleChange('initValue', 'first', false);
+        const changeA = new SimpleChange(undefined, 'first', true);
         const changeB = new SimpleChange(undefined, 'second', true);
         expect(myDir.log).toEqual(['ngOnChanges', 'valA', changeA, 'valB', changeB, 'ngDoCheck']);
       });
@@ -75,7 +75,7 @@ describe('define', () => {
         myDir.valA = 'first';
         myDir.valB = 'second';
         (MyDirective.ngDirectiveDef as DirectiveDef<MyDirective>).doCheck !.call(myDir);
-        const changeA1 = new SimpleChange('initValue', 'first', false);
+        const changeA1 = new SimpleChange(undefined, 'first', true);
         const changeB1 = new SimpleChange(undefined, 'second', true);
         expect(myDir.log).toEqual(['valA', changeA1, 'valB', changeB1]);