assertTrue($x)
Fail if $x is false

assertFalse($x)
Fail if $x is true

assertNull($x)
Fail if $x is set

assertNotNull($x)
Fail if $x not set

assertIsA($x, $t)
Fail if $x is not the class or type $t

assertNotA($x, $t)
Fail if $x is of the class or type $t

assertEqual($x, $y)
Fail if $x == $y is false

assertNotEqual($x, $y)
Fail if $x == $y is true

assertWithinMargin($x, $y, $m)
Fail if abs($x - $y) < $m is false

assertOutsideMargin($x, $y, $m)
Fail if abs($x - $y) < $m is true

assertIdentical($x, $y)
Fail if $x == $y is false or a type mismatch

assertNotIdentical($x, $y)
Fail if $x == $y is true and types match

assertReference($x, $y)
Fail unless $x and $y are the same variable

assertClone($x, $y)
Fail unless $x and $y are identical copies

assertPattern($p, $x)
Fail unless the regex $p matches $x

assertNoPattern($p, $x)
Fail if the regex $p matches $x

expectError($x)
Swallows any upcoming matching error

assert($e)
Fail on failed expectation object $e