Add androidx compose screenshot tests. (#2260)

.github/workflows/ci.yml

@@ -53,7 +53,7 @@ jobs:
                   gradle-home-cache-cleanup: true
 
             - name: Unit tests
-              run: ./gradlew allTests testDebugUnitTest verifyPaparazziDebug verifyRoborazziDebug
+              run: ./gradlew allTests testDebugUnitTest validateDebugScreenshotTest verifyPaparazziDebug verifyRoborazziDebug
 
     instrumentation-tests:
         name: Instrumentation tests

coil-compose/build.gradle.kts

@@ -5,6 +5,7 @@ plugins {
     id("com.android.library")
     id("kotlin-multiplatform")
     id("kotlinx-atomicfu")
+    id("org.jetbrains.compose")
     id("org.jetbrains.kotlin.plugin.compose")
 }
 

gradle.properties

@@ -1,6 +1,7 @@
 org.gradle.jvmargs=-Xmx8g -Xms2g -XX:MaxMetaspaceSize=2g -XX:+UseParallelGC -Dfile.encoding=UTF-8
 
 # Android
+android.experimental.enableScreenshotTest=true
 android.useAndroidX=true
 
 # Disable welcome message.

gradle/libs.versions.toml

@@ -21,10 +21,11 @@ baselineProfile = { id = "androidx.baselineprofile", version.ref = "androidx-ben
 binaryCompatibility = "org.jetbrains.kotlinx.binary-compatibility-validator:0.14.0"
 dokka = "org.jetbrains.dokka:1.9.20"
 poko = "dev.drewhamilton.poko:0.16.0-SNAPSHOT"
+screenshot = "com.android.compose.screenshot:0.0.1-alpha01"
 spotless = "com.diffplug.spotless:6.25.0"
 
 [libraries]
-gradlePlugin-android = "com.android.tools.build:gradle:8.4.0"
+gradlePlugin-android = "com.android.tools.build:gradle:8.5.0-beta01"
 gradlePlugin-atomicFu = "org.jetbrains.kotlinx:atomicfu-gradle-plugin:0.24.0"
 gradlePlugin-jetbrainsCompose = { module = "org.jetbrains.compose:compose-gradle-plugin", version.ref = "jetbrains-compose" }
 gradlePlugin-composeCompiler = { module = "org.jetbrains.kotlin.plugin.compose:org.jetbrains.kotlin.plugin.compose.gradle.plugin", version.ref = "kotlin" }
@@ -39,6 +40,7 @@ androidx-appcompat-resources = "androidx.appcompat:appcompat-resources:1.6.1"
 androidx-annotation = "androidx.annotation:annotation:1.8.0"
 androidx-benchmark-macro = "androidx.benchmark:benchmark-macro-junit4:1.2.4"
 androidx-compose-runtime-tracing = { module = "androidx.compose.runtime:runtime-tracing", version.ref = "androidx-runtime-tracing" }
+androidx-compose-ui-tooling = { group = "androidx.compose.ui", name = "ui-tooling" }
 androidx-constraintlayout = "androidx.constraintlayout:constraintlayout:2.1.4"
 androidx-core = "androidx.core:core-ktx:1.13.1"
 androidx-exifinterface = "androidx.exifinterface:exifinterface:1.3.7"

internal/test-compose-screenshot/build.gradle.kts

@@ -0,0 +1,28 @@
+import coil3.androidLibrary
+
+plugins {
+    id("com.android.library")
+    id("kotlin-android")
+    id("org.jetbrains.compose")
+    id("org.jetbrains.kotlin.plugin.compose")
+    alias(libs.plugins.screenshot)
+}
+
+androidLibrary(name = "coil3.test.composescreenshot") {
+    buildFeatures {
+        compose = true
+    }
+    experimentalProperties["android.experimental.enableScreenshotTest"] = true
+}
+
+dependencies {
+    api(projects.coilCore)
+
+    implementation(projects.coilComposeCore)
+    implementation(projects.coilTest)
+
+    testImplementation(projects.internal.testUtils)
+    testImplementation(libs.bundles.test.jvm)
+
+    screenshotTestImplementation(libs.androidx.compose.ui.tooling)
+}

internal/test-compose-screenshot/src/screenshotTest/java/coil3/composescreenshot/PreviewScreenshots.kt

@@ -0,0 +1,77 @@
+package coil3.composescreenshot
+
+import android.graphics.Color
+import android.graphics.drawable.ColorDrawable
+import androidx.compose.foundation.Image
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.remember
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.layout.ContentScale
+import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.tooling.preview.Devices
+import androidx.compose.ui.tooling.preview.Preview
+import coil3.ImageLoader
+import coil3.compose.AsyncImage
+import coil3.compose.rememberAsyncImagePainter
+import coil3.request.ImageRequest
+import coil3.request.placeholder
+
+class PreviewScreenshots {
+
+    @Preview(
+        device = Devices.PIXEL,
+        showBackground = true,
+    )
+    @Composable
+    fun asyncImage() {
+        val context = LocalContext.current
+        val imageLoader = remember { ImageLoader(context) }
+
+        AsyncImage(
+            // AsyncImagePainter's default preview behaviour displays the request's placeholder.
+            model = ImageRequest.Builder(context)
+                .data(Unit)
+                .placeholder(
+                    object : ColorDrawable(Color.RED) {
+                        override fun getIntrinsicWidth() = 100
+                        override fun getIntrinsicHeight() = 100
+                    },
+                )
+                .build(),
+            contentDescription = null,
+            imageLoader = imageLoader,
+            contentScale = ContentScale.None,
+            modifier = Modifier.fillMaxSize(),
+        )
+    }
+
+    @Preview(
+        device = Devices.PIXEL,
+        showBackground = true,
+    )
+    @Composable
+    fun rememberAsyncImagePainter() {
+        val context = LocalContext.current
+        val imageLoader = remember { ImageLoader(context) }
+
+        Image(
+            painter = rememberAsyncImagePainter(
+                // AsyncImagePainter's default preview behaviour displays the request's placeholder.
+                model = ImageRequest.Builder(context)
+                    .data(Unit)
+                    .placeholder(
+                        object : ColorDrawable(Color.RED) {
+                            override fun getIntrinsicWidth() = 100
+                            override fun getIntrinsicHeight() = 100
+                        },
+                    )
+                    .build(),
+                imageLoader = imageLoader,
+            ),
+            contentDescription = null,
+            contentScale = ContentScale.None,
+            modifier = Modifier.fillMaxSize(),
+        )
+    }
+}

internal/test-paparazzi/build.gradle.kts

@@ -3,8 +3,9 @@ import coil3.androidLibrary
 plugins {
     id("com.android.library")
     id("kotlin-android")
-    id("app.cash.paparazzi")
+    id("org.jetbrains.compose")
     id("org.jetbrains.kotlin.plugin.compose")
+    id("app.cash.paparazzi")
 }
 
 androidLibrary(name = "coil3.test.paparazzi")

internal/test-roborazzi/build.gradle.kts

@@ -3,9 +3,9 @@ import coil3.androidLibrary
 plugins {
     id("com.android.library")
     id("kotlin-android")
-    id("io.github.takahirom.roborazzi")
     id("org.jetbrains.compose")
     id("org.jetbrains.kotlin.plugin.compose")
+    id("io.github.takahirom.roborazzi")
 }
 
 androidLibrary(name = "coil3.test.roborazzi")

settings.gradle.kts

@@ -31,9 +31,10 @@ include(
 // Private modules
 include(
     "internal:benchmark",
-    "internal:test-utils",
+    "internal:test-compose-screenshot",
     "internal:test-paparazzi",
     "internal:test-roborazzi",
+    "internal:test-utils",
     "samples:compose",
     "samples:shared",
     "samples:view",