Option to limit Dagger factory generation to specific source sets

README.md

@@ -237,6 +237,17 @@ sources either.
 When you enable this feature, don't forget to remove the Dagger annotation processor. You should
 keep all other dependencies.
 
+If you want to only enable Dagger factory generation on some source sets 
+(such as only in main source set or only in tests), you can add those source sets
+to the allowlist:
+
+```groovy
+anvil {
+  generateDaggerFactoriesSourceSetAllowlist.add("main")
+}
+```
+
+
 ## Extending Anvil
 
 Every codebase has its own dependency injection patterns where certain code structures need to be

gradle-plugin/src/main/java/com/squareup/anvil/plugin/AnvilExtension.kt

@@ -2,6 +2,7 @@ package com.squareup.anvil.plugin
 
 import org.gradle.api.Action
 import org.gradle.api.model.ObjectFactory
+import org.gradle.api.provider.ListProperty
 import org.gradle.api.provider.Property
 import javax.inject.Inject
 
@@ -33,6 +34,15 @@ public abstract class AnvilExtension @Inject constructor(objects: ObjectFactory)
   public val generateDaggerFactoriesOnly: Property<Boolean> = objects.property(Boolean::class.java)
     .convention(false)
 
+  /**
+   * Allowlist of all source sets (such as main, test etc.) that Anvil should generate dagger
+   * factories in, if factory generation is enabled.
+   *
+   * When empty, Anvil will generate factories in all source sets.
+   */
+  public var generateDaggerFactoriesSourceSetAllowlist: ListProperty<String> =
+    objects.listProperty(String::class.java)
+
   /**
    * Enabling this indicates that only code generation should run and no component merging should
    * run. This is useful for cases where you want to use `@ContributesTo`, `@ContributesBinding`,

gradle-plugin/src/main/java/com/squareup/anvil/plugin/AnvilPlugin.kt

@@ -20,6 +20,7 @@ import org.gradle.api.artifacts.Configuration
 import org.gradle.api.provider.Provider
 import org.gradle.api.tasks.TaskContainer
 import org.gradle.api.tasks.TaskProvider
+import org.jetbrains.kotlin.gradle.dsl.kotlinExtension
 import org.jetbrains.kotlin.gradle.dsl.KotlinVersion.KOTLIN_1_9
 import org.jetbrains.kotlin.gradle.dsl.KotlinVersion.KOTLIN_2_0
 import org.jetbrains.kotlin.gradle.internal.KaptGenerateStubsTask
@@ -29,6 +30,7 @@ import org.jetbrains.kotlin.gradle.plugin.KotlinCompilation
 import org.jetbrains.kotlin.gradle.plugin.KotlinCompilerPluginSupportPlugin
 import org.jetbrains.kotlin.gradle.plugin.KotlinPlatformType.androidJvm
 import org.jetbrains.kotlin.gradle.plugin.KotlinPlatformType.jvm
+import org.jetbrains.kotlin.gradle.plugin.KotlinSourceSet
 import org.jetbrains.kotlin.gradle.plugin.PLUGIN_CLASSPATH_CONFIGURATION_NAME
 import org.jetbrains.kotlin.gradle.plugin.SubpluginArtifact
 import org.jetbrains.kotlin.gradle.plugin.SubpluginOption
@@ -170,6 +172,23 @@ internal open class AnvilPlugin : KotlinCompilerPluginSupportPlugin {
       }
     }
 
+    val allowlistedVariants = variant.variantFilter
+      .generateDaggerFactoriesSourceSetAllowlist.map { sourceSetName ->
+      val sourceSet = variant.kotlinSourceSets.singleOrNull { it.name == sourceSetName }
+        ?: throw GradleException("Unknown variant $sourceSetName. Available variants: " +
+                "${variant.kotlinSourceSets.joinToString { it.name }}"
+        )
+
+      sourceSet
+    }
+
+    val enableDaggerFactoriesInThisVariant = allowlistedVariants.isEmpty() ||
+      variant.androidSourceSets?.any { androidSourceSet ->
+        allowlistedVariants.any { allowlistedSourceSet ->
+          allowlistedSourceSet.name == androidSourceSet.name
+        }
+      } == true
+
     return project.provider {
       listOf(
         FilesSubpluginOption(
@@ -178,11 +197,13 @@ internal open class AnvilPlugin : KotlinCompilerPluginSupportPlugin {
         ),
         SubpluginOption(
           key = "generate-dagger-factories",
-          lazy { variant.variantFilter.generateDaggerFactories.toString() }
+          lazy { (variant.variantFilter.generateDaggerFactories &&
+                  enableDaggerFactoriesInThisVariant).toString() }
         ),
         SubpluginOption(
           key = "generate-dagger-factories-only",
-          lazy { variant.variantFilter.generateDaggerFactoriesOnly.toString() }
+          lazy { (variant.variantFilter.generateDaggerFactoriesOnly &&
+                  enableDaggerFactoriesInThisVariant).toString() }
         ),
         SubpluginOption(
           key = "disable-component-merging",
@@ -359,6 +380,7 @@ internal class Variant private constructor(
   val compileTaskProvider: TaskProvider<KotlinCompile>,
   val androidVariant: BaseVariant?,
   val androidSourceSets: List<AndroidSourceSet>?,
+  val kotlinSourceSets: List<KotlinSourceSet>,
   val compilerPluginClasspathName: String,
   val variantFilter: VariantFilter,
 ) {
@@ -391,6 +413,8 @@ internal class Variant private constructor(
         null
       }
 
+      val kotlinSourceSets = project.kotlinExtension.sourceSets.toList()
+
       val commonFilter = CommonFilter(kotlinCompilation.name, extension)
       val variantFilter = if (androidVariant != null) {
         AndroidVariantFilter(commonFilter, androidVariant)
@@ -406,6 +430,7 @@ internal class Variant private constructor(
           TaskProvider<KotlinCompile>,
         androidVariant = androidVariant,
         androidSourceSets = androidSourceSets,
+        kotlinSourceSets = kotlinSourceSets,
         compilerPluginClasspathName = PLUGIN_CLASSPATH_CONFIGURATION_NAME +
           kotlinCompilation.target.targetName.replaceFirstChar(Char::uppercase) +
           kotlinCompilation.name.replaceFirstChar(Char::uppercase),

gradle-plugin/src/main/java/com/squareup/anvil/plugin/VariantFilter.kt

@@ -24,6 +24,14 @@ public interface VariantFilter : Named {
    */
   public var generateDaggerFactoriesOnly: Boolean
 
+  /**
+   * Allowlist of all source sets (such as main, test etc.) that Anvil should generate dagger
+   * factories in, if factory generation is enabled.
+   *
+   * When empty, Anvil will generate factories in all source sets.
+   */
+  public var generateDaggerFactoriesSourceSetAllowlist: List<String>
+
   /**
    * Indicate whether component merging for this variant should be disabled. The default
    * value comes from the [AnvilExtension]. See [AnvilExtension.disableComponentMerging] for more
@@ -66,6 +74,14 @@ internal class CommonFilter(
       generateDaggerFactoriesOnlyOverride = value
     }
 
+  private var generateDaggerFactoriesSourceSetAllowOverride: List<String>? = null
+  override var generateDaggerFactoriesSourceSetAllowlist: List<String>
+    get() = generateDaggerFactoriesSourceSetAllowOverride
+      ?: extension.generateDaggerFactoriesSourceSetAllowlist.get()
+    set(value) {
+      generateDaggerFactoriesSourceSetAllowOverride = value
+    }
+
   private var disableComponentMergingOverride: Boolean? = null
   override var disableComponentMerging: Boolean
     get() = disableComponentMergingOverride ?: extension.disableComponentMerging.get()