Signals: correctly return zero values (ampproject#23951)

* Signals: correctly return zero values * review fixes
edelight · Aug 14, 2019 · ff414a1 · ff414a1
1 parent 7f86750
commit ff414a1
Show file tree

Hide file tree

Showing 2 changed files with 17 additions and 1 deletion.
diff --git a/src/utils/signals.js b/src/utils/signals.js
@@ -52,7 +52,8 @@ export class Signals {
    * @return {number|!Error|null}
    */
   get(name) {
-    return this.map_[name] || null;
+    const v = this.map_[name];
+    return v == null ? null : v;
   }
 
   /**

diff --git a/test/unit/utils/test-signals.js b/test/unit/utils/test-signals.js
@@ -176,3 +176,18 @@ describes.sandboxed('Signals', {}, () => {
     expect(signals.promiseMap_['sig']).to.be.undefined;
   });
 });
+
+describes.sandboxed('Signals with zero for tests', {}, () => {
+  let signals;
+
+  beforeEach(() => {
+    sandbox.useFakeTimers();
+    signals = new Signals();
+  });
+
+  it('should register signal without promise', () => {
+    // The signal value is often 0 in tests due to the fake timer.
+    signals.signal('sig');
+    expect(signals.get('sig')).to.equal(0);
+  });
+});