Add tests for the new back affordance.

Bug: b/241117239
Test: atest BackPanelControllerTest
Change-Id: Ic708da7102d11f8f133bcba49c6624c9a132eab3

packages/SystemUI/src/com/android/systemui/navigationbar/gestural/BackPanelController.kt

@@ -30,6 +30,7 @@ import android.view.MotionEvent
 import android.view.VelocityTracker
 import android.view.ViewConfiguration
 import android.view.WindowManager
+import androidx.annotation.VisibleForTesting
 import androidx.core.os.postDelayed
 import androidx.core.view.isVisible
 import androidx.dynamicanimation.animation.DynamicAnimation
@@ -52,24 +53,24 @@ private const val ENABLE_FAILSAFE = true
 private const val PX_PER_SEC = 1000
 private const val PX_PER_MS = 1
 
+internal const val MIN_DURATION_ACTIVE_ANIMATION = 300L
 private const val MIN_DURATION_CANCELLED_ANIMATION = 200L
 private const val MIN_DURATION_COMMITTED_ANIMATION = 200L
-private const val MIN_DURATION_ACTIVE_ANIMATION = 300L
 private const val MIN_DURATION_INACTIVE_BEFORE_FLUNG_ANIMATION = 50L
 private const val MIN_DURATION_CONSIDERED_AS_FLING = 100L
 
 private const val FAILSAFE_DELAY_MS = 350L
 private const val POP_ON_FLING_DELAY = 160L
 
-private val VIBRATE_ACTIVATED_EFFECT =
+internal val VIBRATE_ACTIVATED_EFFECT =
         VibrationEffect.createPredefined(VibrationEffect.EFFECT_CLICK)
 
-private val VIBRATE_DEACTIVATED_EFFECT =
+internal val VIBRATE_DEACTIVATED_EFFECT =
         VibrationEffect.createPredefined(VibrationEffect.EFFECT_TICK)
 
 private const val DEBUG = false
 
-class BackPanelController private constructor(
+class BackPanelController internal constructor(
         context: Context,
         private val windowManager: WindowManager,
         private val viewConfiguration: ViewConfiguration,
@@ -114,8 +115,10 @@ class BackPanelController private constructor(
         }
     }
 
-    private var params: EdgePanelParams = EdgePanelParams(resources)
-    private var currentState: GestureState = GestureState.GONE
+    @VisibleForTesting
+    internal var params: EdgePanelParams = EdgePanelParams(resources)
+    @VisibleForTesting
+    internal var currentState: GestureState = GestureState.GONE
     private var previousState: GestureState = GestureState.GONE
 
     // Screen attributes
@@ -159,7 +162,7 @@ class BackPanelController private constructor(
 
     private val failsafeRunnable = Runnable { onFailsafe() }
 
-    private enum class GestureState {
+    internal enum class GestureState {
         /* Arrow is off the screen and invisible */
         GONE,
 

packages/SystemUI/tests/src/com/android/systemui/navigationbar/gestural/BackPanelControllerTest.kt

@@ -0,0 +1,167 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * 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.
+ */
+
+package com.android.systemui.navigationbar.gestural
+
+import android.os.Handler
+import android.os.Looper
+import android.testing.AndroidTestingRunner
+import android.testing.TestableLooper
+import android.view.MotionEvent
+import android.view.MotionEvent.ACTION_DOWN
+import android.view.MotionEvent.ACTION_MOVE
+import android.view.MotionEvent.ACTION_UP
+import android.view.ViewConfiguration
+import android.view.WindowManager
+import androidx.test.filters.SmallTest
+import com.android.internal.util.LatencyTracker
+import com.android.systemui.SysuiTestCase
+import com.android.systemui.plugins.NavigationEdgeBackPlugin
+import com.android.systemui.statusbar.VibratorHelper
+import com.android.systemui.statusbar.policy.ConfigurationController
+import com.google.common.truth.Truth.assertThat
+import org.junit.Before
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.mockito.Mock
+import org.mockito.Mockito.clearInvocations
+import org.mockito.Mockito.verify
+import org.mockito.MockitoAnnotations
+
+@SmallTest
+@RunWith(AndroidTestingRunner::class)
+@TestableLooper.RunWithLooper(setAsMainLooper = true)
+class BackPanelControllerTest : SysuiTestCase() {
+    companion object {
+        private const val START_X: Float = 0f
+    }
+    private lateinit var mBackPanelController: BackPanelController
+    private lateinit var testableLooper: TestableLooper
+    private var triggerThreshold: Float = 0.0f
+    private val touchSlop = ViewConfiguration.get(context).scaledEdgeSlop
+    @Mock private lateinit var vibratorHelper: VibratorHelper
+    @Mock private lateinit var windowManager: WindowManager
+    @Mock private lateinit var configurationController: ConfigurationController
+    @Mock private lateinit var latencyTracker: LatencyTracker
+    @Mock private lateinit var layoutParams: WindowManager.LayoutParams
+    @Mock private lateinit var backCallback: NavigationEdgeBackPlugin.BackCallback
+
+    @Before
+    fun setup() {
+        MockitoAnnotations.initMocks(this)
+        mBackPanelController =
+            BackPanelController(
+                context,
+                windowManager,
+                ViewConfiguration.get(context),
+                Handler.createAsync(Looper.myLooper()),
+                vibratorHelper,
+                configurationController,
+                latencyTracker
+            )
+        mBackPanelController.setLayoutParams(layoutParams)
+        mBackPanelController.setBackCallback(backCallback)
+        mBackPanelController.setIsLeftPanel(true)
+        testableLooper = TestableLooper.get(this)
+        triggerThreshold = mBackPanelController.params.staticTriggerThreshold
+    }
+
+    @Test
+    fun handlesActionDown() {
+        startTouch()
+
+        assertThat(mBackPanelController.currentState)
+            .isEqualTo(BackPanelController.GestureState.GONE)
+    }
+
+    @Test
+    fun staysHiddenBeforeSlopCrossed() {
+        startTouch()
+        // Move just enough to not cross the touch slop
+        continueTouch(START_X + touchSlop - 1)
+
+        assertThat(mBackPanelController.currentState)
+            .isEqualTo(BackPanelController.GestureState.GONE)
+    }
+
+    @Test
+    fun handlesDragSlopCrossed() {
+        startTouch()
+        continueTouch(START_X + touchSlop + 1)
+
+        assertThat(mBackPanelController.currentState)
+            .isEqualTo(BackPanelController.GestureState.ENTRY)
+    }
+
+    @Test
+    fun handlesBackCommitted() {
+        startTouch()
+        // Move once to cross the touch slop
+        continueTouch(START_X + touchSlop.toFloat() + 1)
+        // Move again to cross the back trigger threshold
+        continueTouch(START_X + touchSlop + triggerThreshold + 1)
+
+        assertThat(mBackPanelController.currentState)
+            .isEqualTo(BackPanelController.GestureState.ACTIVE)
+        verify(backCallback).setTriggerBack(true)
+        testableLooper.moveTimeForward(100)
+        testableLooper.processAllMessages()
+        verify(vibratorHelper).vibrate(VIBRATE_ACTIVATED_EFFECT)
+
+        finishTouchActionUp(START_X + touchSlop + triggerThreshold + 1)
+        assertThat(mBackPanelController.currentState)
+            .isEqualTo(BackPanelController.GestureState.FLUNG)
+        verify(backCallback).triggerBack()
+    }
+
+    @Test
+    fun handlesBackCancelled() {
+        startTouch()
+        continueTouch(START_X + touchSlop.toFloat() + 1)
+        continueTouch(
+            START_X + touchSlop + triggerThreshold -
+                mBackPanelController.params.deactivationSwipeTriggerThreshold
+        )
+        clearInvocations(backCallback)
+        Thread.sleep(MIN_DURATION_ACTIVE_ANIMATION)
+        // Move in the opposite direction to cross the deactivation threshold and cancel back
+        continueTouch(START_X)
+
+        assertThat(mBackPanelController.currentState)
+            .isEqualTo(BackPanelController.GestureState.INACTIVE)
+        verify(backCallback).setTriggerBack(false)
+        verify(vibratorHelper).vibrate(VIBRATE_DEACTIVATED_EFFECT)
+
+        finishTouchActionUp(START_X)
+        verify(backCallback).cancelBack()
+    }
+
+    private fun startTouch() {
+        mBackPanelController.onMotionEvent(createMotionEvent(ACTION_DOWN, START_X, 0f))
+    }
+
+    private fun continueTouch(x: Float) {
+        mBackPanelController.onMotionEvent(createMotionEvent(ACTION_MOVE, x, 0f))
+    }
+
+    private fun finishTouchActionUp(x: Float) {
+        mBackPanelController.onMotionEvent(createMotionEvent(ACTION_UP, x, 0f))
+    }
+
+    private fun createMotionEvent(action: Int, x: Float, y: Float): MotionEvent {
+        return MotionEvent.obtain(0L, 0L, action, x, y, 0)
+    }
+}