Avoid clashes with nested type defined in super Interface/Class.

RELNOTES=n/a
PiperOrigin-RevId: 418837115

java/dagger/internal/codegen/javapoet/TypeSpecs.java

@@ -49,9 +49,13 @@ public static TypeSpec.Builder addSupertype(
   public static TypeSpec.Builder addSupertype(TypeSpec.Builder typeBuilder, TypeElement supertype) {
     switch (supertype.getKind()) {
       case CLASS:
-        return typeBuilder.superclass(ClassName.get(supertype));
+        return typeBuilder
+            .superclass(ClassName.get(supertype))
+            .avoidClashesWithNestedClasses(supertype);
       case INTERFACE:
-        return typeBuilder.addSuperinterface(ClassName.get(supertype));
+        return typeBuilder
+            .addSuperinterface(ClassName.get(supertype))
+            .avoidClashesWithNestedClasses(supertype);
       default:
         throw new AssertionError(supertype + " is neither a class nor an interface.");
     }

javatests/dagger/functional/ComponentNestedTypeTest.java

@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2021 The Dagger Authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package dagger.functional;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import dagger.Component;
+import dagger.Module;
+import dagger.Provides;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+/** Regression test for b/212604806. */
+@RunWith(JUnit4.class)
+public final class ComponentNestedTypeTest {
+  @Component(modules = TestModule.class)
+  interface TestComponent {
+
+    // Dagger generated component implementation that extends TestComponent will implement this
+    // method, so the component implementation will keep a reference to the {@link
+    // dagger.functional.sub.NestedType}. The reference to {@link dagger.functional.sub.NestedType}
+    // may collide with the NestedType defined inside of TestComponent, because javapoet may strip
+    // the package prefix of the type as it does not have enough information about the super
+    // class/interfaces.
+    dagger.functional.sub.NestedType nestedType();
+
+    interface NestedType {}
+  }
+
+  public static final class SomeType implements dagger.functional.sub.NestedType {}
+
+  @Module
+  static final class TestModule {
+    @Provides
+    static dagger.functional.sub.NestedType provideSomeType() {
+      return new SomeType();
+    }
+  }
+
+  @Test
+  public void typeNameWontClashWithNestedTypeName() {
+    TestComponent component =
+        DaggerComponentNestedTypeTest_TestComponent.builder().testModule(new TestModule()).build();
+    assertThat(component.nestedType()).isNotNull();
+  }
+}

javatests/dagger/functional/sub/NestedType.java

@@ -0,0 +1,21 @@
+/*
+ * Copyright (C) 2021 The Dagger Authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package dagger.functional.sub;
+
+// Move this back to dagger.functional package once the javapoet clash bug gets fixed.
+// https://github.com/square/javapoet/issues/860
+public interface NestedType {}