Introduce SpaScreenshotTests for SPA screenshot testing.

This CL introduces the SpaScreenshotTests to test a given View for multiple configurations (devices, theme and
orientation).

PreferenceScreenshotTest is added as an example, more screendiff tests will be added in follow-up CLs.

Test: presubmit
Bug: 256770697
Change-Id: I6b62d3cc248cab5bfe9f447e595ba393e9e3c848

packages/SettingsLib/Spa/screenshot/Android.bp

@@ -0,0 +1,41 @@
+//
+// Copyright (C) 2022 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 {
+    default_applicable_licenses: ["frameworks_base_license"],
+}
+
+android_test {
+    name: "SpaScreenshotTests",
+    test_suites: ["device-tests"],
+
+    asset_dirs: ["assets"],
+
+    srcs: ["src/**/*.kt"],
+
+    certificate: "platform",
+
+    static_libs: [
+        "SpaLib",
+        "SpaLibTestUtils",
+        "androidx.compose.runtime_runtime",
+        "androidx.test.ext.junit",
+        "androidx.test.runner",
+        "mockito-target-minus-junit4",
+        "platform-screenshot-diff-core",
+    ],
+    kotlincflags: ["-Xjvm-default=all"],
+}

packages/SettingsLib/Spa/screenshot/AndroidManifest.xml

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+<?xml version="1.0" encoding="utf-8"?><!--
+  Copyright (C) 2022 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.
+  -->
+
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="com.android.settingslib.spa.screenshot">
+
+    <uses-sdk android:minSdkVersion="21"/>
+
+    <application>
+        <uses-library android:name="android.test.runner" />
+        <activity android:name=".DebugActivity" android:exported="true" />
+    </application>
+
+    <instrumentation
+        android:name="androidx.test.runner.AndroidJUnitRunner"
+        android:label="Screenshot tests for SpaLib"
+        android:targetPackage="com.android.settingslib.spa.screenshot">
+    </instrumentation>
+</manifest>

packages/SettingsLib/Spa/screenshot/AndroidTest.xml

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+<!--
+  Copyright (C) 2022 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.
+  -->
+
+<configuration description="Runs screendiff tests.">
+    <option name="test-suite-tag" value="apct-instrumentation" />
+    <option name="test-suite-tag" value="apct" />
+    <target_preparer class="com.android.tradefed.targetprep.DeviceSetup">
+        <option name="optimized-property-setting" value="true" />
+    </target_preparer>
+    <target_preparer class="com.android.tradefed.targetprep.suite.SuiteApkInstaller">
+        <option name="cleanup-apks" value="true" />
+        <option name="test-file-name" value="SpaScreenshotTests.apk" />
+    </target_preparer>
+    <metrics_collector class="com.android.tradefed.device.metric.FilePullerLogCollector">
+        <option name="directory-keys"
+            value="/data/user/0/com.android.settingslib.spa.screenshot/files/settings_screenshots" />
+        <option name="collect-on-run-ended-only" value="true" />
+    </metrics_collector>
+    <test class="com.android.tradefed.testtype.AndroidJUnitTest">
+        <option name="package" value="com.android.settingslib.spa.screenshot" />
+        <option name="runner" value="androidx.test.runner.AndroidJUnitRunner" />
+    </test>
+</configuration>

packages/SettingsLib/Spa/screenshot/src/com/android/settingslib/spa/screenshot/util/Bitmap.kt

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+/*
+ * Copyright (C) 2022 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.settingslib.spa.screenshot
+
+import android.graphics.Bitmap
+import android.graphics.Canvas
+import android.os.Build
+import android.view.View
+import platform.test.screenshot.matchers.MSSIMMatcher
+import platform.test.screenshot.matchers.PixelPerfectMatcher
+
+/** Draw this [View] into a [Bitmap]. */
+// TODO(b/195673633): Remove this once Compose screenshot tests use hardware rendering for their
+// tests.
+fun View.drawIntoBitmap(): Bitmap {
+    val bitmap =
+        Bitmap.createBitmap(
+            measuredWidth,
+            measuredHeight,
+            Bitmap.Config.ARGB_8888,
+        )
+    val canvas = Canvas(bitmap)
+    draw(canvas)
+    return bitmap
+}
+
+/**
+ * The [BitmapMatcher][platform.test.screenshot.matchers.BitmapMatcher] that should be used for
+ * screenshot *unit* tests.
+ */
+val UnitTestBitmapMatcher =
+    if (Build.CPU_ABI == "x86_64") {
+        // Different CPU architectures can sometimes end up rendering differently, so we can't do
+        // pixel-perfect matching on different architectures using the same golden. Given that our
+        // presubmits are run on cf_x86_64_phone, our goldens should be perfectly matched on the
+        // x86_64 architecture and use the Structural Similarity Index on others.
+        // TODO(b/237511747): Run our screenshot presubmit tests on arm64 instead so that we can
+        // do pixel perfect matching both at presubmit time and at development time with actual
+        // devices.
+        PixelPerfectMatcher()
+    } else {
+        MSSIMMatcher()
+    }
+
+/**
+ * The [BitmapMatcher][platform.test.screenshot.matchers.BitmapMatcher] that should be used for
+ * screenshot *unit* tests.
+ *
+ * We use the Structural Similarity Index for integration tests because they usually contain
+ * additional information and noise that shouldn't break the test.
+ */
+val IntegrationTestBitmapMatcher = MSSIMMatcher()

packages/SettingsLib/Spa/screenshot/src/com/android/settingslib/spa/screenshot/util/DefaultDeviceEmulationSpec.kt

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+/*
+ * Copyright (C) 2022 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.settingslib.spa.screenshot
+
+import platform.test.screenshot.DeviceEmulationSpec
+import platform.test.screenshot.DisplaySpec
+
+/**
+ * The emulations specs for all 8 permutations of:
+ * - phone or tablet.
+ * - dark of light mode.
+ * - portrait or landscape.
+ */
+val DeviceEmulationSpec.Companion.PhoneAndTabletFull
+    get() = PhoneAndTabletFullSpec
+
+private val PhoneAndTabletFullSpec =
+    DeviceEmulationSpec.forDisplays(Displays.Phone, Displays.Tablet)
+
+/**
+ * The emulations specs of:
+ * - phone + light mode + portrait.
+ * - phone + light mode + landscape.
+ * - tablet + dark mode + portrait.
+ *
+ * This allows to test the most important permutations of a screen/layout with only 3
+ * configurations.
+ */
+val DeviceEmulationSpec.Companion.PhoneAndTabletMinimal
+    get() = PhoneAndTabletMinimalSpec
+
+private val PhoneAndTabletMinimalSpec =
+    DeviceEmulationSpec.forDisplays(Displays.Phone, isDarkTheme = false) +
+        DeviceEmulationSpec.forDisplays(Displays.Tablet, isDarkTheme = true, isLandscape = false)
+
+object Displays {
+    val Phone =
+        DisplaySpec(
+            "phone",
+            width = 1440,
+            height = 3120,
+            densityDpi = 560,
+        )
+
+    val Tablet =
+        DisplaySpec(
+            "tablet",
+            width = 2560,
+            height = 1600,
+            densityDpi = 320,
+        )
+}

packages/SettingsLib/Spa/screenshot/src/com/android/settingslib/spa/screenshot/util/SettingsGoldenImagePathManager.kt

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+/*
+ * Copyright (C) 2022 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.settingslib.spa.screenshot
+
+import androidx.test.platform.app.InstrumentationRegistry
+import platform.test.screenshot.GoldenImagePathManager
+import platform.test.screenshot.PathConfig
+
+/** A [GoldenImagePathManager] that should be used for all Settings screenshot tests. */
+class SettingsGoldenImagePathManager(
+    pathConfig: PathConfig,
+    assetsPathRelativeToBuildRoot: String
+) :
+    GoldenImagePathManager(
+        appContext = InstrumentationRegistry.getInstrumentation().context,
+        assetsPathRelativeToBuildRoot = assetsPathRelativeToBuildRoot,
+        deviceLocalPath =
+        InstrumentationRegistry.getInstrumentation()
+            .targetContext
+            .filesDir
+            .absolutePath
+            .toString() + "/settings_screenshots",
+        pathConfig = pathConfig,
+    ) {
+    override fun toString(): String {
+        // This string is appended to all actual/expected screenshots on the device, so make sure
+        // it is a static value.
+        return "SettingsGoldenImagePathManager"
+    }
+}

packages/SettingsLib/Spa/screenshot/src/com/android/settingslib/spa/screenshot/util/SettingsScreenshotTestRule.kt

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+/*
+ * Copyright (C) 2022 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.settingslib.spa.screenshot
+
+import androidx.activity.ComponentActivity
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Surface
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.platform.ViewRootForTest
+import androidx.compose.ui.test.junit4.createAndroidComposeRule
+import androidx.compose.ui.test.onRoot
+import com.android.settingslib.spa.framework.theme.SettingsTheme
+import org.junit.rules.RuleChain
+import org.junit.rules.TestRule
+import org.junit.runner.Description
+import org.junit.runners.model.Statement
+import platform.test.screenshot.DeviceEmulationRule
+import platform.test.screenshot.DeviceEmulationSpec
+import platform.test.screenshot.MaterialYouColorsRule
+import platform.test.screenshot.ScreenshotTestRule
+import platform.test.screenshot.getEmulatedDevicePathConfig
+
+/** A rule for Settings screenshot diff tests. */
+class SettingsScreenshotTestRule(
+    emulationSpec: DeviceEmulationSpec,
+    assetsPathRelativeToBuildRoot: String
+) : TestRule {
+    private val colorsRule = MaterialYouColorsRule()
+    private val deviceEmulationRule = DeviceEmulationRule(emulationSpec)
+    private val screenshotRule =
+        ScreenshotTestRule(
+            SettingsGoldenImagePathManager(
+                getEmulatedDevicePathConfig(emulationSpec),
+                assetsPathRelativeToBuildRoot
+            )
+        )
+    private val composeRule = createAndroidComposeRule<ComponentActivity>()
+    private val delegateRule =
+        RuleChain.outerRule(colorsRule)
+            .around(deviceEmulationRule)
+            .around(screenshotRule)
+            .around(composeRule)
+    private val matcher = UnitTestBitmapMatcher
+
+    override fun apply(base: Statement, description: Description): Statement {
+        return delegateRule.apply(base, description)
+    }
+
+    /**
+     * Compare [content] with the golden image identified by [goldenIdentifier] in the context of
+     * [testSpec].
+     */
+    fun screenshotTest(
+        goldenIdentifier: String,
+        content: @Composable () -> Unit,
+    ) {
+        // Make sure that the activity draws full screen and fits the whole display.
+        val activity = composeRule.activity
+        activity.mainExecutor.execute { activity.window.setDecorFitsSystemWindows(false) }
+
+        // Set the content using the AndroidComposeRule to make sure that the Activity is set up
+        // correctly.
+        composeRule.setContent {
+            SettingsTheme {
+                Surface(
+                    color = MaterialTheme.colorScheme.background,
+                ) {
+                    content()
+                }
+            }
+        }
+        composeRule.waitForIdle()
+
+        val view = (composeRule.onRoot().fetchSemanticsNode().root as ViewRootForTest).view
+        screenshotRule.assertBitmapAgainstGolden(view.drawIntoBitmap(), goldenIdentifier, matcher)
+    }
+}

packages/SettingsLib/Spa/screenshot/src/com/android/settingslib/spa/screenshot/widget/PreferenceScreenshotTest.kt

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+/*
+ * Copyright (C) 2022 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.settingslib.spa.screenshot
+
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.outlined.Autorenew
+import androidx.compose.material.icons.outlined.DisabledByDefault
+import androidx.compose.runtime.Composable
+import com.android.settingslib.spa.framework.compose.toState
+import com.android.settingslib.spa.widget.preference.Preference
+import com.android.settingslib.spa.widget.preference.PreferenceModel
+import com.android.settingslib.spa.widget.scaffold.RegularScaffold
+import com.android.settingslib.spa.widget.ui.SettingsIcon
+import org.junit.Rule
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.junit.runners.Parameterized
+import platform.test.screenshot.DeviceEmulationSpec
+
+/** A screenshot test for ExampleFeature. */
+@RunWith(Parameterized::class)
+class PreferenceScreenshotTest(emulationSpec: DeviceEmulationSpec) {
+    companion object {
+        @Parameterized.Parameters(name = "{0}")
+        @JvmStatic
+        fun getTestSpecs() = DeviceEmulationSpec.PhoneAndTabletFull
+        private const val TITLE = "Title"
+        private const val SUMMARY = "Summary"
+        private const val LONG_SUMMARY =
+            "Long long long long long long long long long long long long long long long summary"
+    }
+
+    @get:Rule
+    val screenshotRule =
+        SettingsScreenshotTestRule(
+            emulationSpec,
+            "frameworks/base/packages/SettingsLib/Spa/screenshot/assets"
+        )
+
+    @Test
+    fun testPreference() {
+        screenshotRule.screenshotTest("preference") {
+            RegularScaffold(title = "Preference") {
+                Preference(object : PreferenceModel {
+                    override val title = TITLE
+                })
+
+                Preference(object : PreferenceModel {
+                    override val title = TITLE
+                    override val summary = SUMMARY.toState()
+                })
+
+                Preference(object : PreferenceModel {
+                    override val title = TITLE
+                    override val summary = LONG_SUMMARY.toState()
+                })
+
+                Preference(object : PreferenceModel {
+                    override val title = TITLE
+                    override val summary = SUMMARY.toState()
+                    override val enabled = false.toState()
+                    override val icon = @Composable {
+                        SettingsIcon(imageVector = Icons.Outlined.DisabledByDefault)
+                    }
+                })
+
+                Preference(object : PreferenceModel {
+                    override val title = TITLE
+                    override val summary = SUMMARY.toState()
+                    override val icon = @Composable {
+                        SettingsIcon(imageVector = Icons.Outlined.Autorenew)
+                    }
+                })
+            }
+        }
+    }
+}