FBExpect is a standalone unit testing utility based on the notion of assertions from PHPUnit. Starting with 2.x, FBExpect no longer uses PHPUnit as a dependency, and instead implements the assertions directly, and is intentended for use with HackTest.

It is linguistically clear which value is the expected value and which is the actual value:

use function Facebook\FBExpect\expect;

// PHPUnit
$this->assertSame($a, $b);

// FBExpect
expect($b)->toBeSame($a);

use function Facebook\FBExpect\expect;

// PHPUnit
$this->assertNotNull($x); // Actual test
assert($x !== null); // Tell the typechecker what's going on
$this->assertInstanceOf(Foo::class, $y);
assert($y instanceof Foo);

// FBExpect
$x = expect($x)->toNotBeNull();
$y = expect($y)->toBeInstanceOf(Foo::class);

FBExpect is installed via composer:

composer require facebook/fbexpect

Composer must be executed with php, not HHVM.

FBExpect is MIT-licensed.