/*
 * Copyright 2021 Google Inc. All Rights Reserved.
 *
 * 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;

/** Unit tests for {@link PublicApiNamedStreamShouldReturnStream}. */
@RunWith(JUnit4.class)
public class PublicApiNamedStreamShouldReturnStreamTest {

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

  @Test
  public void abstractMethodPositiveCase() {
    compilationHelper
        .addSourceLines(
            "in/Test.java",
            """
            public abstract class Test {
              // BUG: Diagnostic contains: PublicApiNamedStreamShouldReturnStream
              public abstract int stream();
            }
            """)
        .doTest();
  }

  @Test
  public void regularMethodPositiveCase() {
    compilationHelper
        .addSourceLines(
            "in/Test.java",
            """
            public class Test {
              // BUG: Diagnostic contains: PublicApiNamedStreamShouldReturnStream
              public String stream() {
                return "hello";
              }
            }
            """)
        .doTest();
  }

  @Test
  public void compliantNegativeCase() {
    compilationHelper
        .addSourceLines(
            "in/Test.java",
            """
            import java.util.stream.Stream;

            public abstract class Test {
              public abstract Stream<Integer> stream();
            }
            """)
        .doTest();
  }

  @Test
  public void differentNameNegativeCase() {
    compilationHelper
        .addSourceLines(
            "in/Test.java",
            """
            public class Test {
              public int differentMethodName() {
                return 0;
              }
            }
            """)
        .doTest();
  }

  @Test
  public void privateMethodNegativeCase() {
    compilationHelper
        .addSourceLines(
            "in/Test.java",
            """
            public class Test {
              private String stream() {
                return "hello";
              }
            }
            """)
        .doTest();
  }

  @Test
  public void returnTypeEndingWithStreamNegativeCase() {
    compilationHelper
        .addSourceLines(
            "in/Test.java",
            """
            public class Test {
              private static class TestStream {}

              public TestStream stream() {
                return new TestStream();
              }
            }
            """)
        .doTest();
  }

  @Test
  public void returnTypeNotEndingWithStreamPositiveCase() {
    compilationHelper
        .addSourceLines(
            "in/Test.java",
            """
            public class Test {
              private static class TestStreamRandomSuffix {}

              // BUG: Diagnostic contains: PublicApiNamedStreamShouldReturnStream
              public TestStreamRandomSuffix stream() {
                return new TestStreamRandomSuffix();
              }
            }
            """)
        .doTest();
  }
}
