Unify audio playback under App component

ts/test-electron/state/selectors/audioPlayer_test.ts

@@ -0,0 +1,32 @@
+// Copyright 2021 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import { assert } from 'chai';
+import { actions } from '../../../state/ducks/audioPlayer';
+import { noopAction } from '../../../state/ducks/noop';
+import { isPaused } from '../../../state/selectors/audioPlayer';
+import { StateType, reducer as rootReducer } from '../../../state/reducer';
+
+describe('state/selectors/audioPlayer', () => {
+  const getEmptyRootState = (): StateType => {
+    return rootReducer(undefined, noopAction());
+  };
+
+  describe('isPaused', () => {
+    it('returns true if state.audioPlayer.activeAudioID is undefined', () => {
+      const state = getEmptyRootState();
+      assert.isTrue(isPaused(state));
+    });
+
+    it('returns false if state.audioPlayer.activeAudioID is not undefined', () => {
+      const state = getEmptyRootState();
+
+      const updated = rootReducer(
+        state,
+        actions.setActiveAudioID('id', 'context')
+      );
+
+      assert.isFalse(isPaused(updated));
+    });
+  });
+});