/*
 * Copyright 2016 The Error Prone 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 com.google.errorprone.bugpatterns.inject.dagger;

import com.google.errorprone.BugCheckerRefactoringTestHelper;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;

/**
 * @author Gregory Kick (gak@google.com)
 */
@RunWith(JUnit4.class)
public final class PrivateConstructorForNoninstantiableModuleTest {
  private final BugCheckerRefactoringTestHelper testHelper =
      BugCheckerRefactoringTestHelper.newInstance(
          PrivateConstructorForNoninstantiableModule.class, getClass());

  @Test
  public void emptyModuleGetsLeftAlone() {
    testHelper
        .addInputLines(
            "in/Test.java",
            """
            import dagger.Module;

            @Module
            class Test {}
            """)
        .expectUnchanged()
        .doTest();
  }

  @Test
  public void onlyStaticMethods() {
    testHelper
        .addInputLines(
            "in/TestModule.java",
            """
            import dagger.Module;
            import dagger.Provides;

            @Module
            final class TestModule {
              @Provides
              static String provideString() {
                return "";
              }

              @Provides
              static Integer provideInteger() {
                return 1;
              }
            }
            """)
        .addOutputLines(
            "out/TestModule.java",
            """
            import dagger.Module;
            import dagger.Provides;

            @Module
            final class TestModule {
              @Provides
              static String provideString() {
                return "";
              }

              @Provides
              static Integer provideInteger() {
                return 1;
              }

              private TestModule() {}
            }
            """)
        .doTest();
  }

  @Test
  public void onlyStaticMethods_withConstructorGetsLeftAlone() {
    testHelper
        .addInputLines(
            "in/TestModule.java",
            """
            import dagger.Module;
            import dagger.Provides;

            @Module
            final class TestModule {
              @Provides
              static String provideString() {
                return "";
              }

              @Provides
              static Integer provideInteger() {
                return 1;
              }

              private TestModule() {}
            }
            """)
        .expectUnchanged()
        .doTest();
  }

  @Test
  public void abstractClassWithStaticAndAbstractMethods() {
    testHelper
        .addInputLines(
            "in/TestModule.java",
            """
            import dagger.Binds;
            import dagger.Module;
            import dagger.Provides;

            @Module
            abstract class TestModule {
              @Provides
              static String provideString() {
                return "";
              }

              @Binds
              abstract Object bindObject(String string);

              @Provides
              static Integer provideInteger() {
                return 1;
              }

              @Binds
              abstract Number bindNumber(Integer integer);
            }
            """)
        .addOutputLines(
            "out/TestModule.java",
            """
            import dagger.Binds;
            import dagger.Module;
            import dagger.Provides;

            @Module
            abstract class TestModule {
              @Provides
              static String provideString() {
                return "";
              }

              @Binds
              abstract Object bindObject(String string);

              @Provides
              static Integer provideInteger() {
                return 1;
              }

              @Binds
              abstract Number bindNumber(Integer integer);

              private TestModule() {}
            }
            """)
        .doTest();
  }

  @Test
  public void abstractClassWithStaticAndAbstractMethods_withConstructorGetsLeftAlone() {
    testHelper
        .addInputLines(
            "in/TestModule.java",
            """
            import dagger.Binds;
            import dagger.Module;
            import dagger.Provides;

            @Module
            abstract class TestModule {
              @Provides
              static String provideString() {
                return "";
              }

              @Binds
              abstract Object bindObject(String string);

              @Provides
              static Integer provideInteger() {
                return 1;
              }

              @Binds
              abstract Number bindNumber(Integer integer);

              private TestModule() {}
            }
            """)
        .expectUnchanged()
        .doTest();
  }

  @Test
  public void onlyAbstractMethods() {
    testHelper
        .addInputLines(
            "in/TestModule.java",
            """
            import dagger.Binds;
            import dagger.Module;

            @Module
            abstract class TestModule {
              @Binds
              abstract Object bindObject(String string);

              @Binds
              abstract Number bindNumber(Integer integer);
            }
            """)
        .addOutputLines(
            "out/TestModule.java",
            """
            import dagger.Binds;
            import dagger.Module;

            @Module
            abstract class TestModule {
              @Binds
              abstract Object bindObject(String string);

              @Binds
              abstract Number bindNumber(Integer integer);

              private TestModule() {}
            }
            """)
        .doTest();
  }

  @Test
  public void onlyAbstractMethods_withConstructorGetsLeftAlone() {
    testHelper
        .addInputLines(
            "in/TestModule.java",
            """
            import dagger.Binds;
            import dagger.Module;

            @Module
            abstract class TestModule {
              @Binds
              abstract Object bindObject(String string);

              @Binds
              abstract Number bindNumber(Integer integer);

              private TestModule() {}
            }
            """)
        .expectUnchanged()
        .doTest();
  }

  @Test
  public void interfaceModuleGetsLeftAlone() {
    testHelper
        .addInputLines(
            "in/TestModule.java",
            """
            import dagger.Binds;
            import dagger.Module;

            @Module
            interface TestModule {
              @Binds
              Object bindObject(String string);

              @Binds
              Number bindNumber(Integer integer);
            }
            """)
        .expectUnchanged()
        .doTest();
  }
}
