From 028799fe4738504dbfd83cdc5983da6f160fdb0f Mon Sep 17 00:00:00 2001
From: Robert Jackson <rjackson@linkedin.com>
Date: Thu, 28 Feb 2019 12:53:22 -0500
Subject: [PATCH] [BUGFIX canary] Ensure @tracked setter triggers a
 revalidation.

Prior to this change, setting a tracked property when there was on
ambient runloop would never schedule a revalidation and would therefore
never rerender.

This change ensures that _any_ set of a `@tracked` property will enqueue
a revalidation regardless if there is a current runloop or not.
---
 .../integration/components/tracked-test.js    | 31 +++++++++++++++++++
 packages/@ember/-internals/metal/lib/tags.ts  |  2 +-
 .../@ember/-internals/metal/lib/tracked.ts    |  4 +--
 3 files changed, 34 insertions(+), 3 deletions(-)

diff --git a/packages/@ember/-internals/glimmer/tests/integration/components/tracked-test.js b/packages/@ember/-internals/glimmer/tests/integration/components/tracked-test.js
index f9cd31f0bee..f9653c3644e 100644
--- a/packages/@ember/-internals/glimmer/tests/integration/components/tracked-test.js
+++ b/packages/@ember/-internals/glimmer/tests/integration/components/tracked-test.js
@@ -32,6 +32,37 @@ if (EMBER_METAL_TRACKED_PROPERTIES) {
         this.assertText('1');
       }
 
+      '@test tracked properties rerender when updated outside of a runloop'(assert) {
+        let done = assert.async();
+
+        let CountComponent = Component.extend({
+          count: tracked({ value: 0 }),
+
+          increment() {
+            setTimeout(() => {
+              this.count++;
+            }, 100);
+          },
+        });
+
+        this.registerComponent('counter', {
+          ComponentClass: CountComponent,
+          template: '<button {{action this.increment}}>{{this.count}}</button>',
+        });
+
+        this.render('<Counter />');
+
+        this.assertText('0');
+
+        // intentionally outside of a runTask
+        this.$('button').click();
+
+        setTimeout(() => {
+          this.assertText('1');
+          done();
+        }, 200);
+      }
+
       '@test nested tracked properties rerender when updated'() {
         let Counter = EmberObject.extend({
           count: tracked({ value: 0 }),
diff --git a/packages/@ember/-internals/metal/lib/tags.ts b/packages/@ember/-internals/metal/lib/tags.ts
index 61483a1a51d..845e2abc1b9 100644
--- a/packages/@ember/-internals/metal/lib/tags.ts
+++ b/packages/@ember/-internals/metal/lib/tags.ts
@@ -94,7 +94,7 @@ export function markObjectAsDirty(obj: object, propertyKey: string, meta: Meta):
   }
 }
 
-function ensureRunloop(): void {
+export function ensureRunloop(): void {
   if (hasViews()) {
     backburner.ensureInstance();
   }
diff --git a/packages/@ember/-internals/metal/lib/tracked.ts b/packages/@ember/-internals/metal/lib/tracked.ts
index d8ef7e0cf4e..da11883e11a 100644
--- a/packages/@ember/-internals/metal/lib/tracked.ts
+++ b/packages/@ember/-internals/metal/lib/tracked.ts
@@ -4,7 +4,7 @@ import { DEBUG } from '@glimmer/env';
 import { combine, CONSTANT_TAG, Tag } from '@glimmer/reference';
 import { Decorator, ElementDescriptor } from './decorator';
 import { setComputedDecorator } from './descriptor_map';
-import { dirty, tagFor, tagForProperty } from './tags';
+import { dirty, ensureRunloop, tagFor, tagForProperty } from './tags';
 
 type Option<T> = T | null;
 
@@ -255,7 +255,7 @@ export interface Interceptors {
   [key: string]: boolean;
 }
 
-let propertyDidChange = function(): void {};
+let propertyDidChange = ensureRunloop;
 
 export function setPropertyDidChange(cb: () => void): void {
   propertyDidChange = cb;