Migrate to using AGP's new variant API in the 'variant' package.

This change adds compatibility classes to support registering an ASM transform in AGP 4.2, 7.0 and 7.1. For 4.2 reflection has to be used for all invocations of the newer variant API since their package in 4.2 is different and its not possible to reference the classes when compiling against a newer version. For 7.0 an onwards, the API are stable and can be referenced directly.

Fixes #2700

RELNOTES=Fix an incompatibility in the Hilt Gradle Plugin with AGP 7.0-beta04 and 7.1-alpha03, be aware that with this fix the HiltGradlePlugin will not work with other older alpha/beta versions of AGP 7.0 and 7.1 other than the ones mentioned in these notes.
PiperOrigin-RevId: 383895392

java/dagger/hilt/android/plugin/build.gradle

@@ -16,7 +16,7 @@
 
 buildscript {
   ext {
-    agp_version = System.getenv('AGP_VERSION') ?: "7.0.0-beta01"
+    agp_version = System.getenv('AGP_VERSION') ?: "7.0.0-beta04"
   }
   repositories {
     google()

java/dagger/hilt/android/plugin/src/main/kotlin/dagger/hilt/android/plugin/HiltGradlePlugin.kt

@@ -18,8 +18,6 @@ package dagger.hilt.android.plugin
 
 import com.android.build.api.attributes.BuildTypeAttr
 import com.android.build.api.attributes.ProductFlavorAttr
-import com.android.build.api.component.Component
-import com.android.build.api.extension.AndroidComponentsExtension
 import com.android.build.api.instrumentation.FramesComputationMode
 import com.android.build.api.instrumentation.InstrumentationScope
 import com.android.build.gradle.AppExtension
@@ -34,9 +32,10 @@ import com.android.build.gradle.api.UnitTestVariant
 import dagger.hilt.android.plugin.task.AggregateDepsTask
 import dagger.hilt.android.plugin.task.HiltTransformTestClassesTask
 import dagger.hilt.android.plugin.util.AggregatedPackagesTransform
+import dagger.hilt.android.plugin.util.AndroidComponentsExtensionCompat.Companion.getAndroidComponentsExtension
+import dagger.hilt.android.plugin.util.ComponentCompat
 import dagger.hilt.android.plugin.util.CopyTransform
 import dagger.hilt.android.plugin.util.SimpleAGPVersion
-import dagger.hilt.android.plugin.util.allTestVariants
 import dagger.hilt.android.plugin.util.getSdkPath
 import java.io.File
 import javax.inject.Inject
@@ -234,7 +233,7 @@ class HiltGradlePlugin @Inject constructor(
   @Suppress("UnstableApiUsage") // ASM Pipeline APIs
   private fun configureBytecodeTransformASM(project: Project, hiltExtension: HiltExtension) {
     var warnAboutLocalTestsFlag = false
-    fun registerTransform(androidComponent: Component) {
+    fun registerTransform(androidComponent: ComponentCompat) {
       if (hiltExtension.enableTransformForLocalTests && !warnAboutLocalTestsFlag) {
         project.logger.warn(
           "The Hilt configuration option 'enableTransformForLocalTests' is no longer necessary " +
@@ -254,13 +253,7 @@ class HiltGradlePlugin @Inject constructor(
         FramesComputationMode.COMPUTE_FRAMES_FOR_INSTRUMENTED_METHODS
       )
     }
-
-    val androidComponents = project.extensions.getByType(AndroidComponentsExtension::class.java)
-    androidComponents.onVariants { registerTransform(it) }
-    androidComponents.allTestVariants(
-      onAndroidTest = { registerTransform(it) },
-      onUnitTest = { registerTransform(it) }
-    )
+    getAndroidComponentsExtension(project).onAllVariants { registerTransform(it) }
   }
 
   private fun configureBytecodeTransform(project: Project, hiltExtension: HiltExtension) {

java/dagger/hilt/android/plugin/src/main/kotlin/dagger/hilt/android/plugin/util/AndroidGradleCompat.kt

@@ -16,44 +16,154 @@
 
 package dagger.hilt.android.plugin.util
 
-import com.android.build.api.AndroidPluginVersion
-import com.android.build.api.component.AndroidTest
-import com.android.build.api.component.UnitTest
-import com.android.build.api.extension.AndroidComponentsExtension
-import com.android.build.api.extension.VariantSelector
+import com.android.build.api.variant.Component
+import com.android.build.api.variant.AndroidComponentsExtension
+import com.android.build.api.instrumentation.AsmClassVisitorFactory
+import com.android.build.api.instrumentation.FramesComputationMode
+import com.android.build.api.instrumentation.InstrumentationParameters
+import com.android.build.api.instrumentation.InstrumentationScope
 import com.android.build.api.variant.ApplicationVariant
 import com.android.build.api.variant.LibraryVariant
+import org.gradle.api.Project
 
 /**
- * Compatibility method to go over each Variant as Component (the newer
- * 'android.build.api.variant.Variant' version, not the older one
- * 'com.android.build.gradle.api.BaseVariant')
+ * Compatibility version of [com.android.build.api.variant.AndroidComponentsExtension]
+ * - In AGP 4.2 its package is 'com.android.build.api.extension'
+ * - In AGP 7.0 its packages is 'com.android.build.api.variant'
  */
-@Suppress("UnstableApiUsage")
-fun AndroidComponentsExtension<*, *, *>.allTestVariants(
-  onAndroidTest: (AndroidTest) -> Unit,
-  onUnitTest: (UnitTest) -> Unit
-) {
-  if (
-    findClass("com.android.build.api.AndroidPluginVersion") != null &&
-    this.pluginVersion >= AndroidPluginVersion(7, 0).beta(1)
-  ) {
-    this.onVariants { variant ->
-      when (variant) {
-        is ApplicationVariant -> variant.androidTest
-        is LibraryVariant -> variant.androidTest
-        else -> null
-      }?.let { onAndroidTest(it) }
-      variant.unitTest?.let { onUnitTest(it) }
+sealed class AndroidComponentsExtensionCompat {
+
+  /**
+   * A combined compatibility function of
+   * [com.android.build.api.variant.AndroidComponentsExtension.onVariants] that includes also
+   * [AndroidTest] and [UnitTest] variants.
+   */
+  abstract fun onAllVariants(block: (ComponentCompat) -> Unit)
+
+  class Api70Impl(
+    private val actual: AndroidComponentsExtension<*, *, *>
+  ) : AndroidComponentsExtensionCompat() {
+    override fun onAllVariants(block: (ComponentCompat) -> Unit) {
+      actual.onVariants { variant ->
+        when (variant) {
+          is ApplicationVariant -> variant.androidTest
+          is LibraryVariant -> variant.androidTest
+          else -> null
+        }?.let { block.invoke(ComponentCompat.Api70Impl(it)) }
+        variant.unitTest?.let { block.invoke(ComponentCompat.Api70Impl(it)) }
+      }
+    }
+  }
+
+  class Api42Impl(private val actual: Any) : AndroidComponentsExtensionCompat() {
+
+    private val extensionClazz =
+      Class.forName("com.android.build.api.extension.AndroidComponentsExtension")
+
+    private val variantSelectorClazz =
+      Class.forName("com.android.build.api.extension.VariantSelector")
+
+    override fun onAllVariants(block: (ComponentCompat) -> Unit) {
+      val selector = extensionClazz.getDeclaredMethod("selector").invoke(actual)
+      val allSelector = variantSelectorClazz.getDeclaredMethod("all").invoke(selector)
+      val wrapFunction: (Any) -> Unit = {
+        block.invoke(ComponentCompat.Api42Impl(it))
+      }
+      listOf("onVariants", "androidTests", "unitTests").forEach { methodName ->
+        extensionClazz.getDeclaredMethod(
+          methodName, variantSelectorClazz, Function1::class.java
+        ).invoke(actual, allSelector, wrapFunction)
+      }
+    }
+  }
+
+  companion object {
+    fun getAndroidComponentsExtension(project: Project): AndroidComponentsExtensionCompat {
+      return if (
+        findClass("com.android.build.api.variant.AndroidComponentsExtension") != null
+      ) {
+        val actualExtension = project.extensions.getByType(AndroidComponentsExtension::class.java)
+        Api70Impl(actualExtension)
+      } else {
+        val actualExtension = project.extensions.getByType(
+          Class.forName("com.android.build.api.extension.AndroidComponentsExtension")
+        )
+        Api42Impl(actualExtension)
+      }
+    }
+  }
+}
+
+/**
+ * Compatibility version of [com.android.build.api.variant.Component]
+ * - In AGP 4.2 its package is 'com.android.build.api.component'
+ * - In AGP 7.0 its packages is 'com.android.build.api.variant'
+ */
+@Suppress("UnstableApiUsage") // ASM Pipeline APIs
+sealed class ComponentCompat {
+
+  /**
+   * Redeclaration of [com.android.build.api.variant.ComponentIdentity.name]
+   */
+  abstract val name: String
+
+  /**
+   * Redeclaration of [com.android.build.api.variant.Component.transformClassesWith]
+   */
+  abstract fun <ParamT : InstrumentationParameters> transformClassesWith(
+    classVisitorFactoryImplClass: Class<out AsmClassVisitorFactory<ParamT>>,
+    scope: InstrumentationScope,
+    instrumentationParamsConfig: (ParamT) -> Unit
+  )
+
+  /**
+   * Redeclaration of [com.android.build.api.variant.Component.setAsmFramesComputationMode]
+   */
+  abstract fun setAsmFramesComputationMode(mode: FramesComputationMode)
+
+  class Api70Impl(private val component: Component) : ComponentCompat() {
+
+    override val name: String
+      get() = component.name
+
+    override fun <ParamT : InstrumentationParameters> transformClassesWith(
+      classVisitorFactoryImplClass: Class<out AsmClassVisitorFactory<ParamT>>,
+      scope: InstrumentationScope,
+      instrumentationParamsConfig: (ParamT) -> Unit
+    ) {
+      component.transformClassesWith(
+        classVisitorFactoryImplClass, scope, instrumentationParamsConfig
+      )
+    }
+
+    override fun setAsmFramesComputationMode(mode: FramesComputationMode) {
+      component.setAsmFramesComputationMode(mode)
+    }
+  }
+
+  class Api42Impl(private val actual: Any) : ComponentCompat() {
+
+    private val componentClazz = Class.forName("com.android.build.api.component.Component")
+
+    override val name: String
+      get() = componentClazz.getMethod("getName").invoke(actual) as String
+
+    override fun <ParamT : InstrumentationParameters> transformClassesWith(
+      classVisitorFactoryImplClass: Class<out AsmClassVisitorFactory<ParamT>>,
+      scope: InstrumentationScope,
+      instrumentationParamsConfig: (ParamT) -> Unit
+    ) {
+      componentClazz.getDeclaredMethod(
+        "transformClassesWith",
+        Class::class.java, InstrumentationScope::class.java, Function1::class.java
+      ).invoke(actual, classVisitorFactoryImplClass, scope, instrumentationParamsConfig)
+    }
+
+    override fun setAsmFramesComputationMode(mode: FramesComputationMode) {
+      componentClazz.getDeclaredMethod(
+        "setAsmFramesComputationMode", FramesComputationMode::class.java
+      ).invoke(actual, mode)
     }
-  } else {
-    // This methods were removed in 7.0.0-beta01 but are available in 4.2.0
-    AndroidComponentsExtension::class.java.getDeclaredMethod(
-      "androidTests", VariantSelector::class.java, Function1::class.java
-    ).invoke(this, this.selector().all(), onAndroidTest)
-    AndroidComponentsExtension::class.java.getDeclaredMethod(
-      "unitTests", VariantSelector::class.java, Function1::class.java
-    ).invoke(this, this.selector().all(), onUnitTest)
   }
 }