Merge pull request #3704 from cartant/run-finally

fix(TestScheduler): restore run changes upon error
ReactiveX · May 21, 2018 · bc49e40 · bc49e40
2 parents 294fa2f + 27cb9b6
commit bc49e40
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Showing 2 changed files with 31 additions and 9 deletions.
diff --git a/spec/schedulers/TestScheduler-spec.ts b/spec/schedulers/TestScheduler-spec.ts
@@ -1,5 +1,6 @@
 import { expect } from 'chai';
 import { hot, cold, expectObservable, expectSubscriptions, time } from '../helpers/marble-testing';
+import { AsyncScheduler } from 'rxjs/internal/scheduler/AsyncScheduler';
 import { TestScheduler } from 'rxjs/testing';
 import { Observable, NEVER, EMPTY, Subject, of, concat, merge, Notification } from 'rxjs';
 import { delay, debounceTime, concatMap } from 'rxjs/operators';
@@ -441,5 +442,25 @@ describe('TestScheduler', () => {
         done();
       });
     });
+
+    it('should restore changes upon thrown errors', () => {
+      const testScheduler = new TestScheduler(assertDeepEquals);
+
+      const frameTimeFactor = TestScheduler['frameTimeFactor'];
+      const maxFrames = testScheduler.maxFrames;
+      const runMode = testScheduler['runMode'];
+      const delegate = AsyncScheduler.delegate;
+
+      try {
+        testScheduler.run(() => {
+          throw new Error('kaboom!');
+        });
+      } catch { /* empty */ }
+
+      expect(TestScheduler['frameTimeFactor']).to.equal(frameTimeFactor);
+      expect(testScheduler.maxFrames).to.equal(maxFrames);
+      expect(testScheduler['runMode']).to.equal(runMode);
+      expect(AsyncScheduler.delegate).to.equal(delegate);
+    });
   });
 });
diff --git a/src/internal/testing/TestScheduler.ts b/src/internal/testing/TestScheduler.ts
@@ -378,14 +378,15 @@ export class TestScheduler extends VirtualTimeScheduler {
       expectObservable: this.expectObservable.bind(this),
       expectSubscriptions: this.expectSubscriptions.bind(this),
     };
-    const ret = callback(helpers);
-    this.flush();
-
-    TestScheduler.frameTimeFactor = prevFrameTimeFactor;
-    this.maxFrames = prevMaxFrames;
-    this.runMode = false;
-    AsyncScheduler.delegate = undefined;
-
-    return ret;
+    try {
+      const ret = callback(helpers);
+      this.flush();
+      return ret;
+    } finally {
+      TestScheduler.frameTimeFactor = prevFrameTimeFactor;
+      this.maxFrames = prevMaxFrames;
+      this.runMode = false;
+      AsyncScheduler.delegate = undefined;
+    }
   }
 }