Address code review comments for FakeCaptureController: use UNLIMITED channel and add simulateCaptureEvent

Author: temcguir

ui/controller/testing/src/main/java/com/google/jetpackcamera/ui/controller/testing/FakeCaptureController.kt

@@ -33,14 +33,23 @@ import kotlinx.coroutines.channels.ReceiveChannel
  * @param setAudioEnabledAction The action to perform when [setAudioEnabled] is called.
  */
 class FakeCaptureController(
-    override val captureEvents: ReceiveChannel<CaptureEvent> = Channel(),
+    override val captureEvents: ReceiveChannel<CaptureEvent> = Channel(Channel.UNLIMITED),
     var captureImageAction: (ContentResolver) -> Unit = {},
     var startVideoRecordingAction: () -> Unit = {},
     var stopVideoRecordingAction: () -> Unit = {},
     var setLockedRecordingAction: (Boolean) -> Unit = {},
     var setPausedAction: (Boolean) -> Unit = {},
     var setAudioEnabledAction: (Boolean) -> Unit = {}
 ) : CaptureController {
+    /**
+     * Simulates a [CaptureEvent] being emitted by the controller.
+     * This relies on the [captureEvents] instance being a [Channel].
+     */
+    fun simulateCaptureEvent(event: CaptureEvent) {
+        (captureEvents as? Channel<CaptureEvent>)?.trySend(event)
+            ?: throw IllegalStateException("captureEvents is not a Channel")
+    }
+
     override fun captureImage(contentResolver: ContentResolver) {
         captureImageAction(contentResolver)
     }

ui/controller/testing/src/test/java/com/google/jetpackcamera/ui/controller/testing/FakeCaptureControllerTest.kt

@@ -20,6 +20,7 @@ import android.content.Context
 import androidx.test.core.app.ApplicationProvider
 import com.google.common.truth.Truth.assertThat
 import com.google.jetpackcamera.model.CaptureEvent
+import com.google.jetpackcamera.model.ImageCaptureEvent
 import kotlinx.coroutines.channels.Channel
 import org.junit.Test
 import org.junit.runner.RunWith
@@ -34,6 +35,16 @@ class FakeCaptureControllerTest {
         assertThat(controller.captureEvents).isEqualTo(channel)
     }
 
+    @Test
+    fun simulateCaptureEvent_emitsToCaptureEventsChannel() {
+        val controller = FakeCaptureController()
+        val event = ImageCaptureEvent.SingleImageSaved()
+        controller.simulateCaptureEvent(event)
+
+        val receivedEvent = controller.captureEvents.tryReceive().getOrNull()
+        assertThat(receivedEvent).isEqualTo(event)
+    }
+
     @Test
     fun captureImage_invokesAction() {
         var calledResolver: ContentResolver? = null