[added] Scheduler.isActive unit tests

Summary: Closes #81

Reviewers: featherless, O2 Material Motion

Reviewed By: featherless, O2 Material Motion

Subscribers: featherless

Tags: #material_motion

Differential Revision: http://codereview.cc/D1741

packages/runtime/src/__tests__/Scheduler-isActive.test.ts

@@ -0,0 +1,139 @@
+/** @license
+ *  Copyright 2016 - present The Material Motion Authors. All Rights Reserved.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ *  use this file except in compliance with the License. You may obtain a copy
+ *  of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ *  License for the specific language governing permissions and limitations
+ *  under the License.
+ */
+
+import { expect } from 'chai';
+
+import {
+  beforeEach,
+  describe,
+  it,
+} from 'mocha-sugar-free';
+
+import {
+  spy,
+} from 'sinon';
+
+import Scheduler from '../Scheduler';
+
+class ActivityTestingPerformer {
+  tokens = [];
+
+  constructor({ isActiveTokenGenerator }) {
+    this.isActiveTokenGenerator = isActiveTokenGenerator;
+  }
+
+  addPlan({ plan, target }) {
+    if (plan.type === 'start') {
+      this.tokens = [this.isActiveTokenGenerator.generateToken(), ...this.tokens];
+
+    } else if (plan.type === 'end') {
+      const [dyingToken, ...tokens] = this.tokens;
+      dyingToken.terminate();
+      this.tokens = tokens;
+    }
+  }
+}
+
+const startActivityPlan = {
+  type: 'start',
+  _PerformerType: ActivityTestingPerformer,
+};
+
+const endActivityPlan = {
+  type: 'end',
+  _PerformerType: ActivityTestingPerformer,
+};
+
+describe('Scheduler.addPlan',
+  () => {
+    let scheduler;
+    let target = {};
+
+    beforeEach(
+      () => {
+        scheduler = new Scheduler();
+      }
+    );
+
+    it(`should start at rest`,
+      () => {
+        expect(scheduler.isActive).to.be.false;
+      }
+    );
+
+    it(`should become active when a continuous performer is added`,
+      () => {
+        scheduler.addPlan({ plan: startActivityPlan, target });
+        expect(scheduler.isActive).to.be.true;
+      }
+    );
+
+    it(`should be active when some continuous performers have not completed`,
+      () => {
+        scheduler.addPlan({ plan: startActivityPlan, target });
+        scheduler.addPlan({ plan: startActivityPlan, target });
+        scheduler.addPlan({ plan: endActivityPlan, target });
+
+        expect(scheduler.isActive).to.be.true;
+      }
+    );
+
+    it(`should be at rest when all continuous performers have completed`,
+      () => {
+        scheduler.addPlan({ plan: startActivityPlan, target });
+        scheduler.addPlan({ plan: startActivityPlan, target });
+        scheduler.addPlan({ plan: endActivityPlan, target });
+        scheduler.addPlan({ plan: endActivityPlan, target });
+
+        expect(scheduler.isActive).to.be.false;
+      }
+    );
+
+    it(`should support multiple activity listeners`,
+      () => {
+        const spy1 = spy();
+        const spy2 = spy();
+
+        scheduler.addActivityListener({ listener: spy1 });
+        scheduler.addActivityListener({ listener: spy2 });
+
+        scheduler.addPlan({ plan: startActivityPlan, target });
+
+        expect(spy1.lastCall.args[0].isActive).to.be.true;
+        expect(spy2.lastCall.args[0].isActive).to.be.true;
+      }
+    );
+
+    it(`should stop calling a removed listener`,
+      () => {
+        const spy1 = spy();
+        const spy2 = spy();
+
+        scheduler.addActivityListener({ listener: spy1 });
+        scheduler.addActivityListener({ listener: spy2 });
+
+        scheduler.addPlan({ plan: startActivityPlan, target });
+
+        scheduler.removeActivityListener({ listener: spy2 });
+
+        scheduler.addPlan({ plan: endActivityPlan, target });
+
+        expect(spy1.lastCall.args[0].isActive).to.be.false;
+        expect(spy2.lastCall.args[0].isActive).to.be.true;
+      }
+    );
+  }
+);