/*
 * Copyright 2015 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;

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

/** {@link NullableVoid}Test */
@RunWith(JUnit4.class)
public class NullableVoidTest {

  private final CompilationTestHelper compilationHelper =
      CompilationTestHelper.newInstance(NullableVoid.class, getClass());

  @Test
  public void positive() {
    compilationHelper
        .addSourceLines(
            "Test.java",
            """
            import javax.annotation.Nullable;

            class Test {
              // BUG: Diagnostic contains:
              @Nullable
              void f() {}
            }
            """)
        .doTest();
  }

  @Test
  public void positiveConstructor() {
    compilationHelper
        .addSourceLines(
            "Test.java",
            """
            import javax.annotation.Nullable;

            class Test {
              // BUG: Diagnostic contains:
              @Nullable
              Test() {}
            }
            """)
        .doTest();
  }

  @Test
  public void positiveCheckForNull() {
    compilationHelper
        .addSourceLines(
            "Test.java",
            """
            import javax.annotation.CheckForNull;

            class Test {
              // BUG: Diagnostic contains:
              @CheckForNull
              void f() {}
            }
            """)
        .doTest();
  }

  @Test
  public void negativeNotAnnotated() {
    compilationHelper
        .addSourceLines(
            "Test.java",
            """
            class Test {
              public void f() {}
            }
            """)
        .doTest();
  }

  @Test
  public void negativeBoxedVoid() {
    compilationHelper
        .addSourceLines(
            "Test.java",
            """
            import javax.annotation.Nullable;

            class Test {
              @Nullable
              Void f() {
                return null;
              }
            }
            """)
        .doTest();
  }

  // regression test for #418
  @Test
  public void typeParameter() {
    compilationHelper
        .addSourceLines(
            "Nullable.java",
            """
            import java.lang.annotation.ElementType;
            import java.lang.annotation.Retention;
            import java.lang.annotation.RetentionPolicy;
            import java.lang.annotation.Target;

            @Retention(RetentionPolicy.RUNTIME)
            @Target(ElementType.TYPE_USE)
            public @interface Nullable {}
            """)
        .addSourceLines(
            "Test.java",
            """
            class Test {
              <@Nullable T> void f(T t) {}
            }
            """)
        .doTest();
  }
}
