在Gradle中使用JUnit测试抛出的异常

我在Gradle项目中使用JUnit 5。我正试图在P1包中测试此主要功能:

public static void main(String[] args) {
    // Gets command line arguments
    String fileName = null;
    if (args != null && args.length == 1) {
      fileName = args[0];
    } else {
      throw new IllegalArgumentException("Please specify name of file.");
    }

    // Initializes file and scanner from provided path
    File file = new File(fileName);
    Scanner scanner = null;
    try {
      scanner = new Scanner(file);
    } catch (FileNotFoundException e) {
      System.out.println("File not found: " + e.getMessage());
      System.exit(1);
    }
}

特别是底部的try-catch块。这是我写的测试:

@Test
public void testMissingFile() {
    String[] args = { "bad_file" };
    FileNotFoundException thrown = assertThrows(
        FileNotFoundException.class,
        () -> P1.main(args));

    assertTrue(thrown.getMessage().contains("File not found:"));
}

不幸的是,此测试失败,输出来自 gradle test --info :

TestP1 > testMissingFile() STANDARD_OUT
    File not found: bad_file (No such file or directory)

我试图捕捉这个错误并测试它是否被抛出,但它破坏了测试。我希望测试在检查FileNotFoundException并断言错误消息的内容时通过断言。