PHPUnit在对象创建中测试断言

Question

When I run phpunit I get:

1) FooTests::testException assert(): Assertion "false" failed

I would like to expect the assert in the case I have.

class FooTests extends WP_UnitTestCase {

  protected $foo;

    public function setUp() {
        parent::setUp();
        $this->foo = new Foo();
    }

    function testException() {
        // I'd like to expect an assert in the class foo so the test should not fail.  
        $this->foo->test();
    }
}

class Foo {
    public function __construct(){
    }

    public function __destruct(){}


    public function test(){
      assert('false');
    }

}

Answer 1

You can achieve in one of the following manner:

1) Catch the PHPUnit warning exception

PHP emit a warning for each failed assertion, so PHPUnit raise an exception of the type PHPUnit_Framework_Error_Warning. As described in the doc:

By default, PHPUnit converts PHP errors, warnings, and notices that are triggered during the execution of a test to an exception.

[..]

PHPUnit_Framework_Error_Notice and PHPUnit_Framework_Error_Warning represent PHP notices and warnings, respectively.

So you can simply catch in the following manner:

public function testException() {
    $this->expectException(\PHPUnit_Framework_Error_Warning::class);
    $this->foo->test();
}

2) Using a callback on failed assertion

You could do something more clear using the assert_options, using as callback a custom exception and handle it as example:

public function test_using_assert_options_PHP5()
{
    $fnc = function() {
        throw new \Exception('assertion failed', 500);
    };

    $this->expectException(\Exception::class);
    $this->expectExceptionCode(500);
    $this->expectExceptionMessage('assertion failed');

    assert_options(ASSERT_CALLBACK, $fnc);
    $this->foo->test();
}

3) Change the behaviour of the failing exception (only from PHP7)

If you are using PHP7 you could implement this last behaviour with a new settings called assert.exception:

public function test_using_assert_options_PHP7()
{
    $this->expectException(\AssertionError::class);
    assert_options(ASSERT_EXCEPTION, 1);
    $this->foo->test();
}

Hope this help