Failing tests for #12475

* reduces EF4’s case further
* move related tests to runtime/computed/chains
* adds more thorough tests revealing more related issues

packages/ember-runtime/tests/computed/chains_test.js

@@ -0,0 +1,74 @@
+import { computed } from 'ember-metal/computed';
+import { defineProperty } from 'ember-metal/properties';
+import { get } from 'ember-metal/property_get';
+import { set } from 'ember-metal/property_set';
+import { isWatching } from 'ember-metal/watching';
+import { A as emberA } from 'ember-runtime/system/native_array';
+
+let a1, a2, a3, a4, obj;
+
+QUnit.module('chain watching', {
+  setup() {
+    a1 = { foo: true,  id: 1 };
+    a2 = { foo: true,  id: 2 };
+
+    a3 = { foo: false, id: 3 };
+    a4 = { foo: false, id: 4 };
+
+    obj = { };
+    defineProperty(obj, 'a', computed('array.@each.foo', function() {}));
+  }
+});
+
+QUnit.test('replace array (no overlap)', function() {
+  set(obj, 'array', Ember.A([a1, a2]));
+  get(obj, 'a'); // kick CP;
+
+  ok( isWatching(a1, 'foo'), 'BEFORE: a1.foo is watched');
+  ok( isWatching(a2, 'foo'), 'BEFORE: a2.foo is watched');
+  ok(!isWatching(a3, 'foo'), 'BEFORE: a3.foo is NOT watched');
+  ok(!isWatching(a4, 'foo'), 'BEFORE: a4.foo is NOT watched');
+
+  set(obj, 'array', [a3, a4]);
+
+  ok(!isWatching(a1, 'foo'), 'AFTER: a1.foo is NOT watched');
+  ok(!isWatching(a2, 'foo'), 'AFTER: a2.foo is NOT watched');
+  ok( isWatching(a3, 'foo'), 'AFTER: a3.foo is watched');
+  ok( isWatching(a4, 'foo'), 'AFTER: a4.foo is watched');
+});
+
+QUnit.test('replace array (overlap)', function() {
+  set(obj, 'array', Ember.A([a1, a2, a3]));
+  get(obj, 'a'); // kick CP;
+
+  ok( isWatching(a1, 'foo'), 'BEFORE: a1.foo is watched');
+  ok( isWatching(a2, 'foo'), 'BEFORE: a2.foo is watched');
+  ok( isWatching(a3, 'foo'), 'BEFORE: a3.foo is watched');
+  ok(!isWatching(a4, 'foo'), 'BEFORE: a4.foo is NOT watched');
+
+  obj.set('array', [a2, a3, a4]);
+
+  ok(!isWatching(a1, 'foo'), 'AFTER: a1.foo is NOT watched');
+  ok( isWatching(a2, 'foo'), 'AFTER: a2.foo is watched');
+  ok( isWatching(a3, 'foo'), 'AFTER: a3.foo is watched');
+  ok( isWatching(a4, 'foo'), 'AFTER: a4.foo is watched');
+});
+
+QUnit.test('responds to change of property value on element after replacing array', function() {
+  let obj = { };
+
+  defineProperty(obj, 'a', computed('array.@each.foo', function() {
+    return this.array.filter(elt => elt.foo).reduce(((a,b) => a + b.id), 0);
+  }));
+
+  set(obj, 'array', emberA([a1,a2]));
+
+  deepEqual(get(obj, 'a'), 3, 'value is correct initially');
+  set(a1, 'foo', false);
+  deepEqual(get(obj, 'a'), 2, 'responds to change of property on element');
+  set(obj, 'array', [a1, a2, a3]);
+  deepEqual(get(obj, 'a'), 6, 'responds to content array change');
+  set(a1, 'foo', true);
+  deepEqual(get(obj, 'a'), 7, 'still responds to change of property on element');
+});
+

packages/ember-runtime/tests/computed/reduce_computed_macros_test.js

@@ -428,28 +428,6 @@ QUnit.test('properties values can be replaced', function() {
   deepEqual(obj.get('a1bs').mapBy('name'), ['item1'], 'properties can be filtered by matching value');
 });
 
-QUnit.test('responds to change of property value on element after replacing array', function() {
-  let a1 = { foo: true, id: 1 };
-  let a2 = { foo: true, id: 2 };
-  let a3 = { foo: true, id: 4 };
-
-  obj = EmberObject.extend({
-    a: computed('array.@each.foo', function() {
-      return this.get('array').filter(elt => elt.foo).reduce(((a,b) => a + b.id), 0);
-    })
-  }).create({
-    array: emberA([a1, a2])
-  });
-
-  deepEqual(obj.get('a'), 3, 'value is correct initially');
-  set(a1, 'foo', false);
-  deepEqual(obj.get('a'), 2, 'responds to change of property on element');
-  obj.set('array', [a1, a2, a3]);
-  deepEqual(obj.get('a'), 6, 'responds to content array change');
-  set(a1, 'foo', true);
-  deepEqual(obj.get('a'), 7, 'still responds to change of property on element');
-});
-
 [
   ['uniq', uniq],
   ['union', union]