/*
 * Copyright 2014 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.threadsafety;

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

/** {@link SynchronizeOnNonFinalFieldTest}Test */
@RunWith(JUnit4.class)
public class SynchronizeOnNonFinalFieldTest {
  private final CompilationTestHelper compilationHelper =
      CompilationTestHelper.newInstance(SynchronizeOnNonFinalField.class, getClass());

  @Test
  public void positive1() {
    compilationHelper
        .addSourceLines(
            "threadsafety/Test.java",
            """
            package threadsafety.Test;

            class Test {
              Object lock = new Object();

              void m() {
                // BUG: Diagnostic contains: Synchronizing on non-final fields is not safe
                synchronized (lock) {
                }
              }
            }
            """)
        .doTest();
  }

  @Test
  public void positive2() {
    compilationHelper
        .addSourceLines(
            "threadsafety/Test.java",
            """
            package threadsafety.Test;

            class Test {
              Object lock = new Object();
              Test[] tx = null;

              void m(int i) {
                // BUG: Diagnostic contains: Synchronizing on non-final fields is not safe
                synchronized (this.tx[i].lock) {
                }
              }
            }
            """)
        .doTest();
  }

  @Test
  public void positive3() {
    compilationHelper
        .addSourceLines(
            "threadsafety/Test.java",
            """
            package threadsafety.Test;

            class Test {
              Object lock = new Object();

              void m(Test t) {
                // BUG: Diagnostic contains: Synchronizing on non-final fields is not safe
                synchronized (t.lock) {
                }
              }
            }
            """)
        .doTest();
  }

  @Test
  public void negative() {
    compilationHelper
        .addSourceLines(
            "threadsafety/Test.java",
            """
            package threadsafety.Test;

            class Test {
              final Object lock = new Object();

              void m() {
                synchronized (lock) {
                }
              }
            }
            """)
        .doTest();
  }

  @Test
  public void negative_lazyInit() {
    compilationHelper
        .addSourceLines(
            "threadsafety/Test.java",
            """
            package threadsafety.Test;

            import com.google.errorprone.annotations.concurrent.LazyInit;

            class Test {
              @LazyInit transient Object lock = new Object();

              void m() {
                synchronized (lock) {
                }
              }
            }
            """)
        .doTest();
  }

  @Test
  public void negative_writer() {
    compilationHelper
        .addSourceLines(
            "Test.java",
            """
            import java.io.Writer;

            abstract class Test extends Writer {
              void m() {
                synchronized (lock) {
                }
              }
            }
            """)
        .doTest();
  }
}
