Share Robolectric JVM setup in a convention plugin

android-test/build.gradle.kts

@@ -3,6 +3,7 @@ import okhttp3.buildsupport.androidBuild
 
 plugins {
   id("okhttp.base-conventions")
+  id("okhttp.robolectric-conventions")
   id("com.android.library")
   id("de.mannodermaus.android-junit5")
 }
@@ -43,22 +44,6 @@ android {
   testOptions {
     targetSdk = 37
     unitTests.isIncludeAndroidResources = true
-
-    // Robolectric 4.17 reflects into JDK internals, which JDK 17+ blocks by default.
-    // https://robolectric.org/getting-started/
-    unitTests.all {
-      it.jvmArgs(
-        "--add-opens=java.base/java.lang=ALL-UNNAMED",
-        "--add-opens=java.base/java.util=ALL-UNNAMED",
-        "--add-opens=java.base/java.io=ALL-UNNAMED",
-        "--add-opens=java.base/java.net=ALL-UNNAMED",
-        "--add-opens=java.base/java.security=ALL-UNNAMED",
-        "--add-opens=java.base/java.text=ALL-UNNAMED",
-        "--add-opens=java.base/jdk.internal.access=ALL-UNNAMED",
-        "--add-opens=java.desktop/java.awt.font=ALL-UNNAMED",
-        "--add-opens=jdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED",
-      )
-    }
   }
 
 

build-logic/src/main/kotlin/okhttp.robolectric-conventions.gradle.kts

@@ -0,0 +1,45 @@
+import okhttp3.buildsupport.testJavaVersion
+
+/**
+ * Shared configuration for the modules that run Robolectric tests.
+ *
+ * Robolectric reflects into JDK internals, which JDK 17+ blocks by default, and its newer Android
+ * images need a newer JVM. https://robolectric.org/getting-started/
+ */
+
+/** Opened so Robolectric can reflect into the JDK internals its shadows and interceptors use. */
+val robolectricJvmArgs =
+  listOf(
+    "--add-opens=java.base/java.lang=ALL-UNNAMED",
+    "--add-opens=java.base/java.util=ALL-UNNAMED",
+    "--add-opens=java.base/java.io=ALL-UNNAMED",
+    "--add-opens=java.base/java.net=ALL-UNNAMED",
+    "--add-opens=java.base/java.security=ALL-UNNAMED",
+    "--add-opens=java.base/java.text=ALL-UNNAMED",
+    "--add-opens=java.base/jdk.internal.access=ALL-UNNAMED",
+    "--add-opens=java.desktop/java.awt.font=ALL-UNNAMED",
+    "--add-opens=jdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED",
+  )
+
+tasks.withType<Test>().configureEach {
+  if (testJavaVersion >= 9) {
+    jvmArgs(robolectricJvmArgs)
+  }
+
+  if (testJavaVersion < 21) {
+    // Robolectric needs Java 21 to sandbox Android SDK 37. Tests configured only for SDKs outside
+    // this set are skipped rather than failing to create a sandbox.
+    systemProperty("robolectric.enabledSdks", (21..36).joinToString(","))
+  }
+}
+
+if (testJavaVersion < 9) {
+  afterEvaluate {
+    tasks.withType<Test> {
+      // Work around robolectric requirements and limitations. The Android Gradle Plugin adds
+      // --add-opens itself, which Java 8 doesn't understand.
+      // https://cs.android.com/android-studio/platform/tools/base/+/mirror-goog-studio-main:build-system/gradle-core/src/main/java/com/android/build/gradle/tasks/factory/AndroidUnitTest.java;l=339
+      allJvmArgs = allJvmArgs.filter { !it.startsWith("--add-opens") }
+    }
+  }
+}

okhttp/build.gradle.kts

@@ -16,6 +16,7 @@ plugins {
   id("okhttp.jvm-conventions")
   id("okhttp.quality-conventions")
   id("okhttp.testing-conventions")
+  id("okhttp.robolectric-conventions")
   id("app.cash.burst")
   alias(libs.plugins.maven.sympathy)
 }
@@ -324,20 +325,6 @@ project.tasks.withType<AnimalSniffer> {
   }
 }
 
-afterEvaluate {
-  tasks.withType<Test> {
-    if (javaLauncher
-        .get()
-        .metadata.languageVersion
-        .asInt() < 9
-    ) {
-      // Work around robolectric requirements and limitations
-      // https://cs.android.com/android-studio/platform/tools/base/+/mirror-goog-studio-main:build-system/gradle-core/src/main/java/com/android/build/gradle/tasks/factory/AndroidUnitTest.java;l=339
-      allJvmArgs = allJvmArgs.filter { !it.startsWith("--add-opens") }
-    }
-  }
-}
-
 // Work around issue 8826, where the Sentry SDK assumes that OkHttp's internal-visibility symbols
 // will be suffixed '$okhttp' in deployable artifacts. This isn't intended to be a published API,
 // but it's easy enough for us to keep it working. https://github.com/lysine-dev/okhttp/issues/8826