Add preview test

.github/workflows/ScreenShotTest.yml

@@ -0,0 +1,59 @@
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+
+jobs:
+  screenshot-test:
+    runs-on: ubuntu-latest
+    timeout-minutes: 60
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+
+      - name: Validate Gradle Wrapper
+        uses: gradle/wrapper-validation-action@v1
+
+      - name: Copy CI gradle.properties
+        run: mkdir -p ~/.gradle ; cp .github/ci-gradle.properties ~/.gradle/gradle.properties
+
+      - name: Set up JDK 11
+        uses: actions/setup-java@v1
+        with:
+          java-version: 11
+
+      - name: Setup Gradle
+        uses: gradle/gradle-build-action@v2
+
+      - name: Download Screenshots
+        id: download-artifact
+        uses: dawidd6/action-download-artifact@v2
+        with:
+          workflow: UpdateScreenshots.yml
+          name: screenshots
+          path: preview-screenshots/src/test/snapshots/images
+
+      - name: Run screenshot tests
+        id: verifyPaparazziDebug
+        continue-on-error: true
+        run: ./gradlew preview-screenshots:verifyPaparazziDebug
+
+      - name: Error Screenshot tests
+        continue-on-error: true
+        if: ${{ hashFiles('preview-screenshots/out/failures/*.png') != '' }}
+        uses: actions/upload-artifact@v3
+        with:
+          name: scrennshot-test-results
+          path: preview-screenshots/out/failures
+
+      - name: Comment PR
+        continue-on-error: true
+        if: ${{ hashFiles('preview-screenshots/out/failures/*.png') != '' }}
+        uses: thollander/actions-comment-pull-request@v1
+        with:
+          message: |
+            There are differences in Compose previews. Please check your build and download the diff artifact.
+            https://github.com/DroidKaigi/conference-app-2022/actions/workflows/ScreenShotTest.yml
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

.github/workflows/UpdateScreenshots.yml

@@ -0,0 +1,25 @@
+on:
+  pull_request:
+    branches:
+      - main
+    types: [closed]
+
+jobs:
+  update-screenshot:
+    runs-on: ubuntu-latest
+    if: github.event.pull_request.merged == true
+
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions/setup-java@v1
+        with:
+          java-version: '11'
+      - name: Run Update Screenshots
+        run: ./gradlew recordPaparazziDebug
+
+      - name: Upload Screenshots
+        uses: actions/upload-artifact@v3
+        with:
+          name: screenshots
+          path: preview-screenshots/src/test/snapshots/images
+          retention-days: 15

core-ui/build.gradle.kts

@@ -1,14 +1,19 @@
+// TODO: Remove once https://youtrack.jetbrains.com/issue/KTIJ-19369 is fixed
+@Suppress("DSL_SCOPE_VIOLATION")
 plugins {
     id("droidkaigi.primitive.android")
     id("droidkaigi.primitive.android.kotlin")
     id("droidkaigi.primitive.android.compose")
     id("droidkaigi.primitive.android.hilt")
     id("droidkaigi.primitive.molecule")
     id("droidkaigi.primitive.spotless")
+    alias(libs.plugins.ksp)
 }
 
 android.namespace = "io.github.droidkaigi.confsched2022.template.core.ui"
 
 dependencies {
     implementation(libs.accompanistPager)
+    implementation(libs.showkase.runtime)
+    ksp(libs.showkase.processor)
 }

feature-contributors/build.gradle.kts

@@ -1,5 +1,8 @@
+// TODO: Remove once https://youtrack.jetbrains.com/issue/KTIJ-19369 is fixed
+@Suppress("DSL_SCOPE_VIOLATION")
 plugins {
     id("droidkaigi.convention.androidfeature")
+    alias(libs.plugins.ksp)
 }
 
 android.namespace = "io.github.droidkaigi.confsched2022.feature.contributors"
@@ -23,4 +26,7 @@ dependencies {
     androidTestImplementation(libs.composeUiTestJunit4)
     debugImplementation(libs.composeUiTooling)
     debugImplementation(libs.composeUiTestManifest)
+
+    implementation(libs.showkase.runtime)
+    ksp(libs.showkase.processor)
 }

feature-contributors/src/main/java/io/github/droidkaigi/confsched2022/feature/contributors/Contributors.kt

@@ -28,6 +28,8 @@ import io.github.droidkaigi.confsched2022.designsystem.theme.KaigiScaffold
 import io.github.droidkaigi.confsched2022.designsystem.theme.KaigiTheme
 import io.github.droidkaigi.confsched2022.designsystem.theme.KaigiTopAppBar
 import io.github.droidkaigi.confsched2022.feature.contributors.ContributorsUiModel.ContributorsState.Loaded
+import io.github.droidkaigi.confsched2022.model.Contributor
+import io.github.droidkaigi.confsched2022.model.fakes
 
 @Composable
 fun ContributorsScreenRoot(
@@ -95,6 +97,13 @@ fun Contributors(
 @Composable
 fun ContributorsPreview() {
     KaigiTheme {
-        ContributorsScreenRoot()
+        Contributors(
+            uiModel = ContributorsUiModel(
+                Loaded(
+                    contributors = Contributor.fakes()
+                )
+            ),
+            onNavigationIconClick = {}
+        )
     }
 }

feature-sessions/build.gradle.kts

@@ -1,5 +1,8 @@
+// TODO: Remove once https://youtrack.jetbrains.com/issue/KTIJ-19369 is fixed
+@Suppress("DSL_SCOPE_VIOLATION")
 plugins {
     id("droidkaigi.convention.androidfeature")
+    alias(libs.plugins.ksp)
 }
 
 android.namespace = "io.github.droidkaigi.confsched2022.feature.sessions"
@@ -26,4 +29,7 @@ dependencies {
     androidTestImplementation(libs.composeUiTestJunit4)
     debugImplementation(libs.composeUiTooling)
     debugImplementation(libs.composeUiTestManifest)
+
+    implementation(libs.showkase.runtime)
+    ksp(libs.showkase.processor)
 }

gradle/libs.versions.toml

@@ -43,6 +43,10 @@ kluent = "1.68"
 coilCompose="2.2.0"
 koin = "3.2.0"
 androidXChromeCustomTabs = "1.3.0"
+ksp = "1.7.10-1.0.6"
+paparazzi = "1.1.0-SNAPSHOT"
+showkase = "1.0.0-beta13"
+testParameterInjector = "1.8"
 
 [libraries]
 androidGradlePlugin = { group = "com.android.tools.build", name = "gradle", version.ref = "androidGradlePlugin" }
@@ -120,9 +124,14 @@ androidxTestEspressoEspressoCore = { module = "androidx.test.espresso:espresso-c
 hiltAndroidTesting = { group = "com.google.dagger", name = "hilt-android-testing", version.ref = "dagger" }
 robolectric = { module = "org.robolectric:robolectric", version.ref = "robolectric" }
 kluentAndroid = {module = "org.amshove.kluent:kluent-android", version.ref = "kluent" }
+showkase-runtime = { group = "com.airbnb.android", name = "showkase", version.ref = "showkase" }
+showkase-processor = { group = "com.airbnb.android", name = "showkase-processor", version.ref = "showkase" }
+testParameterInjector = { group = "com.google.testparameterinjector", name = "test-parameter-injector", version.ref = "testParameterInjector" }
 
 [plugins]
 androidGradlePlugin = { id = "com.android.application", version.ref = "androidGradlePlugin" }
 androidGradleLibraryPlugin = { id = "com.android.library", version.ref = "androidGradlePlugin" }
 kotlinPlugin = { id = "org.jetbrains.kotlin.android", version.ref = "kotlin" }
 hiltGradlePlugin = { id = "com.google.dagger.hilt.android", version.ref = "dagger" }
+ksp = { id = "com.google.devtools.ksp", version.ref = "ksp" }
+paparazzi = { id = "app.cash.paparazzi", version.ref = "paparazzi" }

preview-screenshots/.gitignore

@@ -0,0 +1 @@
+/build

preview-screenshots/build.gradle.kts

@@ -0,0 +1,47 @@
+// TODO: Remove once https://youtrack.jetbrains.com/issue/KTIJ-19369 is fixed
+@Suppress("DSL_SCOPE_VIOLATION")
+plugins {
+    id("droidkaigi.primitive.android")
+    id("droidkaigi.primitive.android.kotlin")
+    id("droidkaigi.primitive.android.compose")
+    id("droidkaigi.primitive.molecule")
+    id("droidkaigi.primitive.spotless")
+    alias(libs.plugins.ksp)
+    alias(libs.plugins.paparazzi)
+}
+
+android.namespace = "io.github.droidkaigi.confsched2022.template.preview.screenshots"
+
+androidComponents {
+    // Disable release builds for this test-only library, no need to run screenshot tests more than
+    // once
+    beforeVariants(selector().withBuildType("release")) { builder ->
+        builder.enable = false
+    }
+    beforeVariants(selector().withBuildType("prod")) { builder ->
+        builder.enable = false
+    }
+}
+
+dependencies {
+
+    implementation(project(":core-ui"))
+    implementation(project(":feature-contributors"))
+    implementation(project(":feature-sessions"))
+
+    implementation(libs.composeUi)
+    implementation(libs.showkase.runtime)
+    ksp(libs.showkase.processor)
+
+    testImplementation(projects.coreTesting)
+    testImplementation(libs.testParameterInjector)
+}
+
+tasks.named("check") {
+    dependsOn("verifyPaparazziDemoDebug")
+}
+
+tasks.withType<Test>().configureEach {
+    // Increase memory for Paparazzi tests
+    maxHeapSize = "2g"
+}

preview-screenshots/proguard-rules.pro

@@ -0,0 +1,21 @@
+# Add project specific ProGuard rules here.
+# You can control the set of applied configuration files using the
+# proguardFiles setting in build.gradle.
+#
+# For more details, see
+#   http://developer.android.com/guide/developing/tools/proguard.html
+
+# If your project uses WebView with JS, uncomment the following
+# and specify the fully qualified class name to the JavaScript interface
+# class:
+#-keepclassmembers class fqcn.of.javascript.interface.for.webview {
+#   public *;
+#}
+
+# Uncomment this to preserve the line number information for
+# debugging stack traces.
+#-keepattributes SourceFile,LineNumberTable
+
+# If you keep the line number information, uncomment this to
+# hide the original source file name.
+#-renamesourcefileattribute SourceFile

preview-screenshots/src/main/AndroidManifest.xml

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+
+</manifest>

preview-screenshots/src/test/java/io/github/droidkaigi/confsched2022/PreviewScreenshotTests.kt

@@ -0,0 +1,79 @@
+package io.github.droidkaigi.confsched2022
+
+import androidx.compose.foundation.layout.Box
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.CompositionLocalProvider
+import androidx.compose.ui.platform.LocalDensity
+import androidx.compose.ui.platform.LocalInspectionMode
+import androidx.compose.ui.unit.Density
+import app.cash.paparazzi.DeviceConfig
+import app.cash.paparazzi.Paparazzi
+import app.cash.paparazzi.androidHome
+import app.cash.paparazzi.detectEnvironment
+import com.airbnb.android.showkase.models.Showkase
+import com.airbnb.android.showkase.models.ShowkaseBrowserComponent
+import com.google.testing.junit.testparameterinjector.TestParameter
+import com.google.testing.junit.testparameterinjector.TestParameter.TestParameterValuesProvider
+import com.google.testing.junit.testparameterinjector.TestParameterInjector
+import org.junit.Rule
+import org.junit.Test
+import org.junit.runner.RunWith
+
+class ComponentPreview(
+    private val showkaseBrowserComponent: ShowkaseBrowserComponent
+) {
+    val content: @Composable () -> Unit = showkaseBrowserComponent.component
+    override fun toString(): String = showkaseBrowserComponent.componentKey
+}
+
+@RunWith(TestParameterInjector::class)
+class PreviewScreenshotTests {
+
+    object PreviewProvider : TestParameterValuesProvider {
+        override fun provideValues(): List<ComponentPreview> =
+            Showkase.getMetadata().componentList.map(::ComponentPreview)
+    }
+
+    enum class BaseDeviceConfig(
+        val deviceConfig: DeviceConfig,
+    ) {
+        NEXUS_5(DeviceConfig.NEXUS_5),
+        PIXEL_5(DeviceConfig.PIXEL_5),
+        PIXEL_C(DeviceConfig.PIXEL_C),
+    }
+
+    @get:Rule
+    val paparazzi = Paparazzi(
+        environment = detectEnvironment().copy(
+            platformDir = "${androidHome()}/platforms/android-31",
+            compileSdkVersion = 31
+        ),
+        maxPercentDifference = 0.0,
+    )
+
+    @Test
+    fun preview_tests(
+        @TestParameter(valuesProvider = PreviewProvider::class) componentPreview: ComponentPreview,
+        @TestParameter baseDeviceConfig: BaseDeviceConfig,
+        @TestParameter(value = ["1.0", "1.5"]) fontScale: Float
+    ) {
+        paparazzi.unsafeUpdateConfig(
+            baseDeviceConfig.deviceConfig.copy(
+                softButtons = false,
+            )
+        )
+        paparazzi.snapshot {
+            CompositionLocalProvider(
+                LocalInspectionMode provides true,
+                LocalDensity provides Density(
+                    density = LocalDensity.current.density,
+                    fontScale = fontScale
+                )
+            ) {
+                Box {
+                    componentPreview.content()
+                }
+            }
+        }
+    }
+}

preview-screenshots/src/test/java/io/github/droidkaigi/confsched2022/ScreenshotShowkaseModule.kt

@@ -0,0 +1,7 @@
+package io.github.droidkaigi.confsched2022
+
+import com.airbnb.android.showkase.annotation.ShowkaseRoot
+import com.airbnb.android.showkase.annotation.ShowkaseRootModule
+
+@ShowkaseRoot
+class ScreenshotShowkaseModule : ShowkaseRootModule

settings.gradle.kts

@@ -4,7 +4,7 @@ pluginManagement {
         gradlePluginPortal()
         google()
         mavenCentral()
-//        maven("https://oss.sonatype.org/content/repositories/snapshots/")
+        maven("https://oss.sonatype.org/content/repositories/snapshots/")
     }
 }
 enableFeaturePreview("TYPESAFE_PROJECT_ACCESSORS")
@@ -14,6 +14,7 @@ dependencyResolutionManagement {
     repositories {
         google()
         mavenCentral()
+        maven("https://oss.sonatype.org/content/repositories/snapshots/")
         // for datastore-okio
 //        maven(url = "https://androidx.dev/snapshots/builds/8938977/artifacts/repository") {
 //            content {
@@ -36,7 +37,8 @@ include(
     ":core-designsystem",
     ":core-data",
     ":core-testing",
-    ":core-model"
+    ":core-model",
+    ":preview-screenshots"
 )
 
 // for iOS framework name