/*
 * 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;

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

/** {@link StreamToString}Test */
@RunWith(JUnit4.class)
public class StreamToStringTest {

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

  @Test
  public void positive() {
    compilationHelper
        .addSourceLines(
            "Test.java",
            "import java.util.Arrays;",
            "class Test {",
            "  public static void main(String[] args) {",
            "    // BUG: Diagnostic contains:",
            "    System.err.println(Arrays.asList(42).stream());",
            "    // BUG: Diagnostic contains:",
            "    Arrays.asList(42).stream().toString();",
            "    // BUG: Diagnostic contains:",
            "    String.valueOf(Arrays.asList(42).stream());",
            "    // BUG: Diagnostic contains:",
            "    String s = \"\" + Arrays.asList(42).stream();",
            "  }",
            "}")
        .doTest();
  }

  @Test
  public void negative() {
    compilationHelper
        .addSourceLines(
            "Test.java",
            "import java.util.Arrays;",
            "import java.util.stream.Collectors;",
            "class Test {",
            "  public static void main(String[] args) {",
            "    System.err.println(Arrays.asList(42).stream()",
            "      .map(String::valueOf).collect(Collectors.joining(\", \")));",
            "    String.valueOf(Arrays.asList(42).stream()",
            "      .map(String::valueOf).collect(Collectors.joining(\", \")));",
            "    String s = \"\" + Arrays.asList(42).stream()",
            "      .map(String::valueOf).collect(Collectors.joining(\", \"));",
            "    String.format(\"%s %s\", null, null);",
            "  }",
            "}")
        .doTest();
  }

  @Test
  public void withinStreamClass() {
    compilationHelper
        .addSourceLines(
            "Test.java",
            "public abstract class Test implements java.util.stream.Stream {",
            "  public String s() {",
            "    return toString();",
            "  }",
            "}")
        .doTest();
  }

  @Test
  public void viaJoiner() {
    compilationHelper
        .addSourceLines(
            "Test.java",
            "import com.google.common.base.Joiner;",
            "import java.util.stream.Stream;",
            "class Test {",
            "  public void s(Stream<String> xs) {",
            "    // BUG: Diagnostic contains:",
            "    var x = Joiner.on(\"foo\").join(xs, xs);",
            "    // BUG: Diagnostic contains:",
            "    var y = Joiner.on(\"foo\").join(null, null, new Stream[]{xs});",
            "  }",
            "}")
        .doTest();
  }
}
