Merge pull request #18073 from emberjs/bugfix/tracked/fix-alias-chain…

…-tagging

[BUGFIX] Fixes alias chaining when tracked is enabled

packages/@ember/-internals/metal/lib/chain-tags.ts

@@ -98,7 +98,7 @@ export function getChainTagsForKey(obj: any, key: string) {
         if (typeof descriptor.altKey === 'string') {
           // it's an alias, so just get the altkey without tracking
           track(() => {
-            current = get(obj, descriptor.altKey);
+            current = get(current, descriptor.altKey);
           });
         } else {
           current = peekCacheFor(current).get(segment);

packages/@ember/-internals/metal/tests/alias_test.js

@@ -1,5 +1,6 @@
 import {
   alias,
+  computed,
   defineProperty,
   get,
   set,
@@ -253,5 +254,38 @@ moduleFor(
         assert.equal(get(obj, 'bar'), 'FOO');
       });
     }
+
+    ['@test nested aliases update their chained dependencies properly'](assert) {
+      let count = 0;
+
+      class Inner {
+        @alias('pojo') aliased;
+
+        pojo = {
+          value: 123,
+        };
+      }
+
+      class Outer {
+        @computed('inner.aliased.value')
+        get value() {
+          count++;
+          return this.inner.aliased.value;
+        }
+
+        inner = new Inner();
+      }
+
+      let outer = new Outer();
+
+      assert.equal(outer.value, 123, 'Property works');
+
+      outer.value;
+      assert.equal(count, 1, 'Property was properly cached');
+
+      set(outer, 'inner.pojo.value', 456);
+
+      assert.equal(outer.value, 456, 'Property was invalidated correctly');
+    }
   }
 );