Fix an issue where a class named "Create" can conflict with the creat…

…e() factory method on the component.

Fixes #3069.

RELNOTES=Fix #3069 where a class named "Create" could cause a conflict.
PiperOrigin-RevId: 419019730

java/dagger/internal/codegen/writing/ComponentImplementation.java

@@ -789,6 +789,7 @@ private void createRootComponentFactoryMethod() {
         noArgFactoryMethod = true;
       }
       validateMethodNameDoesNotOverrideGeneratedCreator(creatorKind.methodName());
+      claimMethodName(creatorKind.methodName());
       MethodSpec creatorFactoryMethod =
           methodBuilder(creatorKind.methodName())
               .addModifiers(PUBLIC, STATIC)
@@ -798,6 +799,7 @@ private void createRootComponentFactoryMethod() {
       addMethod(MethodSpecKind.BUILDER_METHOD, creatorFactoryMethod);
       if (noArgFactoryMethod && canInstantiateAllRequirements()) {
         validateMethodNameDoesNotOverrideGeneratedCreator("create");
+        claimMethodName("create");
         addMethod(
             MethodSpecKind.BUILDER_METHOD,
             methodBuilder("create")

javatests/dagger/functional/names/BUILD

@@ -0,0 +1,33 @@
+# 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.
+
+# Description:
+#   Functional tests for Dagger testing various name conflicts.
+
+load("//:build_defs.bzl", "DOCLINT_HTML_AND_SYNTAX")
+load("//:test_defs.bzl", "GenJavaTests")
+
+package(default_visibility = ["//:src"])
+
+# TODO(b/203233586): Replace with GenJavaTest
+GenJavaTests(
+    name = "ComponentFactoryNameConflictsTest",
+    srcs = ["ComponentFactoryNameConflictsTest.java"],
+    javacopts = DOCLINT_HTML_AND_SYNTAX,
+    deps = [
+        "//:dagger_with_compiler",
+        "//third_party/java/junit",
+        "//third_party/java/truth",
+    ],
+)

javatests/dagger/functional/names/ComponentFactoryNameConflictsTest.java

@@ -0,0 +1,88 @@
+/*
+ * 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.names;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import dagger.Component;
+import javax.inject.Inject;
+import javax.inject.Provider;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+/** This is a regression test for https://github.com/google/dagger/issues/3069. */
+@RunWith(JUnit4.class)
+public final class ComponentFactoryNameConflictsTest {
+
+  // A class name "Create" so the private method name in fastInit mode conflicts with the create()
+  // factory method.
+  public static final class Create {
+    // Take a dependency so we don't just inline this directly.
+    @Inject Create(Provider<CreateUsage> provider) {}
+  }
+
+  // Use another class to make sure the create class is used but not a direct component entry point.
+  public static final class CreateUsage {
+    @Inject CreateUsage(Create create) {}
+  }
+
+  @Component
+  interface CreateComponent {
+    CreateUsage getCreateUsage();
+  }
+
+  @Test
+  public void testCreate() {
+    CreateComponent testComponent =
+        DaggerComponentFactoryNameConflictsTest_CreateComponent.create();
+    CreateUsage createUsage = testComponent.getCreateUsage();
+    assertThat(createUsage).isNotNull();
+  }
+
+  // A class name "Builder" so the private method name in fastInit mode conflicts with the builder()
+  // factory method.
+  public static final class Builder {
+    // Take a dependency so we don't just inline this directly.
+    @Inject Builder(Provider<BuilderUsage> provider) {}
+  }
+
+  public static final class BuilderUsage {
+    @Inject BuilderUsage(Builder create) {}
+  }
+
+  @Component
+  interface BuilderComponent {
+    BuilderUsage getBuilderUsage();
+
+    @Component.Builder
+    interface OtherBuilder {
+      BuilderComponent build();
+    }
+  }
+
+  // Technically this test passes without claiming the name "builder" when we add the method (even
+  // though we do anyway for safety) because KeyVariableNamer actually hardcodes a list of common
+  // names to avoid which includes "builder".
+  @Test
+  public void testBuilder() {
+    BuilderComponent testComponent =
+        DaggerComponentFactoryNameConflictsTest_BuilderComponent.builder().build();
+    BuilderUsage builderUsage = testComponent.getBuilderUsage();
+    assertThat(builderUsage).isNotNull();
+  }
+}