public function testException() {
    try {
        $this->methodThatThrowsException();
        $this->fail("Expected Exception has not been raised.");
    } catch (Exception $ex) {
        $this->assertEquals("Exception message", $ex->getMessage());
    }
    
}

PhpUnit是一个很棒的库，但这一点有点令人沮丧。这就是为什么我们可以使用turbotesting-php开源库，它有一个非常方便的断言方法来帮助我们测试异常。在这里可以找到:

https://github.com/edertone/TurboTesting/blob/master/TurboTesting-Php/src/main/php/utils/AssertUtils.php

要使用它，我们只需执行以下操作:

AssertUtils::throwsException(function(){

    // Some code that must throw an exception here

}, '/expected error message/');

如果我们在匿名函数中键入的代码没有抛出异常，则会抛出异常。

如果我们在匿名函数中键入的代码抛出异常，但其消息与预期的regexp不匹配，则也将抛出异常。

另一种方法是:

$this->expectException(\InvalidArgumentException::class);
$this->expectExceptionMessage('Expected Exception Message');

请确保您的测试类扩展\PHPUnit_Framework_TestCase。

PHPUnit expectException方法非常不方便，因为它只允许每个测试方法测试一个异常。

我使用这个helper函数来断言某个函数抛出异常:

/**
 * Asserts that the given callback throws the given exception.
 *
 * @param string $expectClass The name of the expected exception class
 * @param callable $callback A callback which should throw the exception
 */
protected function assertException(string $expectClass, callable $callback)
{
    try {
        $callback();
    } catch (\Throwable $exception) {
        $this->assertInstanceOf($expectClass, $exception, 'An invalid exception was thrown');
        return;
    }

    $this->fail('No exception was thrown');
}

将它添加到您的测试类中，并以这样的方式调用:

public function testSomething() {
    $this->assertException(\PDOException::class, function() {
        new \PDO('bad:param');
    });
    $this->assertException(\PDOException::class, function() {
        new \PDO('foo:bar');
    });
}

对于PHPUnit 5.7.27和PHP 5.6，要在一个测试中测试多个异常，强制进行异常测试是很重要的。如果没有异常发生，则单独使用异常处理来断言exception实例将跳过对情况的测试。

public function testSomeFunction() {

    $e=null;
    $targetClassObj= new TargetClass();
    try {
        $targetClassObj->doSomething();
    } catch ( \Exception $e ) {
    }
    $this->assertInstanceOf(\Exception::class,$e);
    $this->assertEquals('Some message',$e->getMessage());

    $e=null;
    try {
        $targetClassObj->doSomethingElse();
    } catch ( Exception $e ) {
    }
    $this->assertInstanceOf(\Exception::class,$e);
    $this->assertEquals('Another message',$e->getMessage());

}

public function testException() {
    try {
        $this->methodThatThrowsException();
        $this->fail("Expected Exception has not been raised.");
    } catch (Exception $ex) {
        $this->assertEquals("Exception message", $ex->getMessage());
    }
    
}