/*
 * Copyright 2018 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.BugCheckerRefactoringTestHelper;
import com.google.errorprone.CompilationTestHelper;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;

/**
 * Tests for {@link LockNotBeforeTry} bugpattern.
 *
 * @author ghm@google.com (Graeme Morgan)
 */
@RunWith(JUnit4.class)
public final class LockNotBeforeTryTest {
  private final CompilationTestHelper compilationHelper =
      CompilationTestHelper.newInstance(LockNotBeforeTry.class, getClass());
  private final BugCheckerRefactoringTestHelper refactoringHelper =
      BugCheckerRefactoringTestHelper.newInstance(LockNotBeforeTry.class, getClass());

  @Test
  public void positive() {
    compilationHelper
        .addSourceLines(
            "Test.java",
            """
            import java.util.concurrent.locks.ReentrantLock;

            class Test {
              private void test(ReentrantLock lock) {
                try {
                  // BUG: Diagnostic contains:
                  lock.lock();
                } finally {
                  lock.unlock();
                }
              }
            }
            """)
        .doTest();
  }

  @Test
  public void negative() {
    compilationHelper
        .addSourceLines(
            "Test.java",
            """
            import java.util.concurrent.locks.ReentrantLock;

            class Test {
              private void test(ReentrantLock lock) {
                lock.lock();
                try {
                  System.out.println("hi");
                } finally {
                  lock.unlock();
                }
              }
            }
            """)
        .doTest();
  }

  @Test
  public void ignoresMultipleLocks() {
    compilationHelper
        .addSourceLines(
            "Test.java",
            """
            import java.util.concurrent.locks.ReentrantLock;

            class Test {
              private void test(ReentrantLock lockA, ReentrantLock lockB) {
                try {
                  lockA.lock();
                  lockB.lock();
                  System.out.println("hi");
                } finally {
                  lockA.unlock();
                  lockB.unlock();
                }
              }
            }
            """)
        .doTest();
  }

  @Test
  public void refactorToBefore() {
    refactoringHelper
        .addInputLines(
            "Test.java",
            """
            import java.util.concurrent.locks.ReentrantLock;

            class Test {
              private void test(ReentrantLock lock) {
                try {
                  lock.lock();
                  System.out.println("hi");
                } finally {
                  lock.unlock();
                }
              }
            }
            """)
        .addOutputLines(
            "Test.java",
            """
            import java.util.concurrent.locks.ReentrantLock;

            class Test {
              private void test(ReentrantLock lock) {
                lock.lock();
                try {
                  System.out.println("hi");
                } finally {
                  lock.unlock();
                }
              }
            }
            """)
        .doTest();
  }

  @Test
  public void interspersed() {
    refactoringHelper
        .addInputLines(
            "Test.java",
            """
            import java.util.concurrent.locks.ReentrantLock;

            class Test {
              private void test(ReentrantLock lock) {
                try {
                  System.out.println("hi");
                  // BUG: Diagnostic contains:
                  lock.lock();
                  System.out.println("bye");
                } finally {
                  lock.unlock();
                }
              }
            }
            """)
        .expectUnchanged()
        .doTest();
  }

  @Test
  public void refactorIntermediate() {
    refactoringHelper
        .addInputLines(
            "Test.java",
            """
            import java.util.concurrent.locks.ReentrantLock;

            class Test {
              private void test(ReentrantLock lock) {
                lock.lock();
                System.out.println("hi");
                try {
                  System.out.println("hi");
                } finally {
                  lock.unlock();
                }
              }
            }
            """)
        .addOutputLines(
            "Test.java",
            """
            import java.util.concurrent.locks.ReentrantLock;

            class Test {
              private void test(ReentrantLock lock) {
                lock.lock();
                try {
                  System.out.println("hi");
                  System.out.println("hi");
                } finally {
                  lock.unlock();
                }
              }
            }
            """)
        .doTest();
  }

  @Test
  public void refactorUnlockOutsideTry() {
    refactoringHelper
        .addInputLines(
            "Test.java",
            """
            import java.util.concurrent.locks.ReentrantLock;

            class Test {
              private void test(ReentrantLock lock) {
                lock.lock();
                System.out.println("hi");
                lock.unlock();
              }
            }
            """)
        .addOutputLines(
            "Test.java",
            """
            import java.util.concurrent.locks.ReentrantLock;

            class Test {
              private void test(ReentrantLock lock) {
                lock.lock();
                try {
                  System.out.println("hi");
                } finally {
                  lock.unlock();
                }
              }
            }
            """)
        .doTest();
  }

  @Test
  public void twoRegions() {
    refactoringHelper
        .addInputLines(
            "Test.java",
            """
            import java.util.concurrent.locks.ReentrantLock;

            class Test {
              private void test(ReentrantLock lock) {
                lock.lock();
                System.out.println("hi");
                lock.unlock();
                lock.lock();
                try {
                  System.out.println("hi");
                } finally {
                  lock.unlock();
                }
              }
            }
            """)
        .addOutputLines(
            "Test.java",
            """
            import java.util.concurrent.locks.ReentrantLock;

            class Test {
              private void test(ReentrantLock lock) {
                lock.lock();
                try {
                  System.out.println("hi");
                } finally {
                  lock.unlock();
                }
                lock.lock();
                try {
                  System.out.println("hi");
                } finally {
                  lock.unlock();
                }
              }
            }
            """)
        .doTest();
  }

  @Test
  public void unclosed() {
    refactoringHelper
        .addInputLines(
            "Test.java",
            """
            import java.util.concurrent.locks.ReentrantLock;

            class Test {
              private void test(ReentrantLock lock) {
                // BUG: Diagnostic contains:
                lock.lock();
                System.out.println("hi");
                lock.lock();
                try {
                  System.out.println("hi");
                } finally {
                  lock.unlock();
                }
              }
            }
            """)
        .expectUnchanged()
        .doTest();
  }

  @Test
  public void receiverless() {
    compilationHelper
        .addSourceLines(
            "Test.java",
            """
            abstract class Test implements java.util.concurrent.locks.Lock {
              private void test() {
                lock();
                try {
                } finally {
                  unlock();
                }
              }
            }
            """)
        .doTest();
  }

  @Test
  public void receiverless2() {
    compilationHelper
        .addSourceLines(
            "Test.java",
            """
            import java.util.concurrent.locks.Lock;

            abstract class Test implements Lock {
              private void test(Lock l) {
                lock();
                l.lock();
                try {
                } finally {
                  unlock();
                  l.unlock();
                }
              }
            }
            """)
        .doTest();
  }

  @Test
  public void nonInvocationExpression() {
    compilationHelper
        .addSourceLines(
            "Test.java",
            """
            import java.util.concurrent.locks.ReentrantLock;

            abstract class Test {
              private void test(ReentrantLock lock) {
                String s;
                // BUG: Diagnostic contains:
                lock.lock();
                s = lock.toString();
                lock.unlock();
              }
            }
            """)
        .doTest();
  }

  @Test
  public void nullCheck() {
    refactoringHelper
        .addInputLines(
            "Test.java",
            """
            import static java.util.Objects.requireNonNull;
            import java.util.concurrent.locks.ReentrantLock;

            class Test {
              private void test(ReentrantLock lock, Runnable r) {
                lock.lock();
                requireNonNull(r);
                try {
                  r.run();
                } finally {
                  lock.unlock();
                }
              }
            }
            """)
        .addOutputLines(
            "Test.java",
            """
            import static java.util.Objects.requireNonNull;
            import java.util.concurrent.locks.ReentrantLock;

            class Test {
              private void test(ReentrantLock lock, Runnable r) {
                lock.lock();
                try {
                  requireNonNull(r);
                  r.run();
                } finally {
                  lock.unlock();
                }
              }
            }
            """)
        .doTest();
  }
}
