feat(ng-dev): provide a nice error message why trying to use `Angular…

…Context.tick()` outside `.run()` Closes #29
simontonsoftware · Jul 13, 2021 · 396af3c · 396af3c
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diff --git a/projects/ng-dev/src/lib/angular-context/angular-context.spec.ts b/projects/ng-dev/src/lib/angular-context/angular-context.spec.ts
@@ -239,6 +239,15 @@ describe('AngularContext', () => {
         expect(performance.now()).toBe(start + 10);
       });
     });
+
+    it('gives a nice error message when you try to use it outside `run()`', () => {
+      const ctx = new AngularContext();
+      expect(() => {
+        ctx.tick();
+      }).toThrowError(
+        '.tick() only works inside the .run() callback (because it needs to be in a fakeAsync zone)',
+      );
+    });
   });
 
   describe('.verifyPostTestConditions()', () => {

diff --git a/projects/ng-dev/src/lib/angular-context/angular-context.ts b/projects/ng-dev/src/lib/angular-context/angular-context.ts
@@ -154,6 +154,12 @@ export class AngularContext {
    * @param unit The unit of time `amount` represents. Accepts anything described in `@s-libs/s-core`'s [TimeUnit]{@linkcode https://simontonsoftware.github.io/s-js-utils/typedoc/enums/timeunit.html} enum.
    */
   tick(amount = 0, unit = 'ms'): void {
+    if (!Zone.current.get('FakeAsyncTestZoneSpec')) {
+      throw new Error(
+        '.tick() only works inside the .run() callback (because it needs to be in a fakeAsync zone)',
+      );
+    }
+
     // To simulate real life, trigger change detection before processing macro tasks. To further simulate real life, wait until the micro task queue is empty.
     flushMicrotasks();
     this.runChangeDetection();