Fix an issue where internal Kotlin objects were not properly being processed. Consolidate logic to figure out if a module requires an instance.

RELNOTES=Fixes an issue where internal Kotlin object modules were incorrectly depended on directly by the component.
PiperOrigin-RevId: 369743121

5 files changed, 22 insertions, 25 deletions

diff --git a/java/dagger/hilt/processor/internal/Processors.java b/java/dagger/hilt/processor/internal/Processors.java
index f33462dad..8740bd6a0 100644
--- a/java/dagger/hilt/processor/internal/Processors.java
+++ b/java/dagger/hilt/processor/internal/Processors.java
@@ -925,7 +925,10 @@ public final class Processors {
     return ElementFilter.methodsIn(elements.getAllMembers(module)).stream()
         .filter(Processors::isBindingMethod)
         .map(ExecutableElement::getModifiers)
-        .anyMatch(modifiers -> !modifiers.contains(ABSTRACT) && !modifiers.contains(STATIC));
+        .anyMatch(modifiers -> !modifiers.contains(ABSTRACT) && !modifiers.contains(STATIC))
+        // TODO(erichang): Getting a new KotlinMetadataUtil each time isn't great here, but until
+        // we have some sort of dependency management it will be difficult to share the instance.
+        && !KotlinMetadataUtils.getMetadataUtil().isObjectOrCompanionObjectClass(module);
   }
 
   private static boolean isBindingMethod(ExecutableElement method) {
diff --git a/java/dagger/hilt/processor/internal/aggregateddeps/AggregatedDepsProcessor.java b/java/dagger/hilt/processor/internal/aggregateddeps/AggregatedDepsProcessor.java
index ff66e5904..c45b373cb 100644
--- a/java/dagger/hilt/processor/internal/aggregateddeps/AggregatedDepsProcessor.java
+++ b/java/dagger/hilt/processor/internal/aggregateddeps/AggregatedDepsProcessor.java
@@ -37,10 +37,8 @@ import com.squareup.javapoet.ClassName;
 import dagger.hilt.processor.internal.BaseProcessor;
 import dagger.hilt.processor.internal.ClassNames;
 import dagger.hilt.processor.internal.Components;
-import dagger.hilt.processor.internal.KotlinMetadataUtils;
 import dagger.hilt.processor.internal.ProcessorErrors;
 import dagger.hilt.processor.internal.Processors;
-import dagger.internal.codegen.kotlin.KotlinMetadataUtil;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Optional;
@@ -167,7 +165,10 @@ public final class AggregatedDepsProcessor extends BaseProcessor {
     // Check that if Dagger needs an instance of the module, Hilt can provide it automatically by
     // calling a visible empty constructor.
     ProcessorErrors.checkState(
-        !daggerRequiresModuleInstance(module) || hasVisibleEmptyConstructor(module),
+        // Skip ApplicationContextModule, since Hilt manages this module internally.
+        ClassNames.APPLICATION_CONTEXT_MODULE.equals(ClassName.get(module))
+        || !Processors.requiresModuleInstance(getElementUtils(), module)
+        || hasVisibleEmptyConstructor(module),
         module,
         "Modules that need to be instantiated by Hilt must have a visible, empty constructor.");
 
@@ -444,27 +445,6 @@ public final class AggregatedDepsProcessor extends BaseProcessor {
         || name.contentEquals("javax.annotation.processing.Generated");
   }
 
-  private static boolean daggerRequiresModuleInstance(TypeElement module) {
-    return !module.getModifiers().contains(ABSTRACT)
-        && !hasOnlyStaticProvides(module)
-        // Skip ApplicationContextModule, since Hilt manages this module internally.
-        && !ClassNames.APPLICATION_CONTEXT_MODULE.equals(ClassName.get(module))
-        // Skip Kotlin object modules since all their provision methods are static
-        && !isKotlinObject(module);
-  }
-
-  private static boolean isKotlinObject(TypeElement type) {
-    KotlinMetadataUtil metadataUtil = KotlinMetadataUtils.getMetadataUtil();
-    return metadataUtil.isObjectClass(type) || metadataUtil.isCompanionObjectClass(type);
-  }
-
-  private static boolean hasOnlyStaticProvides(TypeElement module) {
-    // TODO(erichang): Check for @Produces too when we have a producers story
-    return ElementFilter.methodsIn(module.getEnclosedElements()).stream()
-        .filter(method -> Processors.hasAnnotation(method, ClassNames.PROVIDES))
-        .allMatch(method -> method.getModifiers().contains(STATIC));
-  }
-
   private static boolean hasVisibleEmptyConstructor(TypeElement type) {
     List<ExecutableElement> constructors = ElementFilter.constructorsIn(type.getEnclosedElements());
     return constructors.isEmpty()
diff --git a/java/dagger/internal/codegen/kotlin/KotlinMetadataUtil.java b/java/dagger/internal/codegen/kotlin/KotlinMetadataUtil.java
index cf80f1a96..980ff3438 100644
--- a/java/dagger/internal/codegen/kotlin/KotlinMetadataUtil.java
+++ b/java/dagger/internal/codegen/kotlin/KotlinMetadataUtil.java
@@ -100,6 +100,11 @@ public final class KotlinMetadataUtil {
         && metadataFactory.create(typeElement).classMetadata().flags(IS_COMPANION_OBJECT);
   }
 
+  /** Returns {@code true} if this type element is a Kotlin object or companion object. */
+  public boolean isObjectOrCompanionObjectClass(TypeElement typeElement) {
+    return isObjectClass(typeElement) || isCompanionObjectClass(typeElement);
+  }
+
   /* Returns {@code true} if this type element has a Kotlin Companion Object. */
   public boolean hasEnclosedCompanionObject(TypeElement typeElement) {
     return hasMetadata(typeElement)
diff --git a/javatests/dagger/hilt/android/InternalKtModuleTest.java b/javatests/dagger/hilt/android/InternalKtModuleTest.java
index b58309313..0b489896e 100644
--- a/javatests/dagger/hilt/android/InternalKtModuleTest.java
+++ b/javatests/dagger/hilt/android/InternalKtModuleTest.java
@@ -37,6 +37,7 @@ public final class InternalKtModuleTest {
   @Rule public final HiltAndroidRule rule = new HiltAndroidRule(this);
 
   @Inject String string;
+  @Inject Integer intValue;
 
   @Before
   public void setUp() {
@@ -46,5 +47,6 @@ public final class InternalKtModuleTest {
   @Test
   public void testBindingFromInternalKtModule() {
     assertThat(string).isEqualTo("expected_string_value");
+    assertThat(intValue).isEqualTo(9);
   }
 }
diff --git a/javatests/dagger/hilt/testmodules/InternalKtTestModule.kt b/javatests/dagger/hilt/testmodules/InternalKtTestModule.kt
index c78f3347f..0a71e445b 100644
--- a/javatests/dagger/hilt/testmodules/InternalKtTestModule.kt
+++ b/javatests/dagger/hilt/testmodules/InternalKtTestModule.kt
@@ -32,3 +32,10 @@ internal abstract class InternalKtTestModule private constructor() {
     fun provideString(): String = "expected_string_value"
   }
 }
+
+@Module
+@InstallIn(SingletonComponent::class)
+internal object InternalKtObjectModule {
+  @Provides
+  fun provideString(): Int = 9
+}