Argument Validation¶
The arguments passed to the with()
declaration when setting up an
expectation determine the criteria for matching method calls to expectations.
Thus, we can setup up many expectations for a single method, each
differentiated by the expected arguments. Such argument matching is done on a
“best fit” basis. This ensures explicit matches take precedence over
generalised matches.
An explicit match is merely where the expected argument and the actual
argument are easily equated (i.e. using ===
or ==
). More generalised
matches are possible using regular expressions, class hinting and the
available generic matchers. The purpose of generalised matchers is to allow
arguments be defined in non-explicit terms, e.g. Mockery::any()
passed to
with()
will match any argument in that position.
Mockery’s generic matchers do not cover all possibilities but offers optional support for the Hamcrest library of matchers. Hamcrest is a PHP port of the similarly named Java library (which has been ported also to Python, Erlang, etc). By using Hamcrest, Mockery does not need to duplicate Hamcrest’s already impressive utility which itself promotes a natural English DSL.
The examples below show Mockery matchers and their Hamcrest equivalent, if there is one. Hamcrest uses functions (no namespacing).
Note
If you don’t wish to use the global Hamcrest functions, they are all exposed
through the \Hamcrest\Matchers
class as well, as static methods. Thus,
identicalTo($arg)
is the same as \Hamcrest\Matchers::identicalTo($arg)
The most common matcher is the with()
matcher:
$mock = \Mockery::mock('MyClass');
$mock->shouldReceive('foo')
->with(1):
It tells mockery that it should receive a call to the foo
method with the
integer 1
as an argument. In cases like this, Mockery first tries to match
the arguments using ===
(identical) comparison operator. If the argument is
a primitive, and if it fails the identical comparison, Mockery does a fallback
to the ==
(equals) comparison operator.
When matching objects as arguments, Mockery only does the strict ===
comparison, which means only the same $object
will match:
$object = new stdClass();
$mock = \Mockery::mock('MyClass');
$mock->shouldReceive("foo")
->with($object);
// Hamcrest equivalent
$mock->shouldReceive("foo")
->with(identicalTo($object));
A different instance of stdClass
will not match.
Note
The Mockery\Matcher\MustBe
matcher has been deprecated.
If we need a loose comparison of objects, we can do that using Hamcrest’s
equalTo
matcher:
$mock->shouldReceive("foo")
->with(equalTo(new stdClass));
In cases when we don’t care about the type, or the value of an argument, just
that any argument is present, we use any()
:
$mock = \Mockery::mock('MyClass');
$mock->shouldReceive("foo")
->with(\Mockery::any());
// Hamcrest equivalent
$mock->shouldReceive("foo")
->with(anything())
Anything and everything passed in this argument slot is passed unconstrained.
Validating Types and Resources¶
The type()
matcher accepts any string which can be attached to is_
to
form a valid type check.
To match any PHP resource, we could do the following:
$mock = \Mockery::mock('MyClass');
$mock->shouldReceive("foo")
->with(\Mockery::type('resource'));
// Hamcrest equivalents
$mock->shouldReceive("foo")
->with(resourceValue());
$mock->shouldReceive("foo")
->with(typeOf('resource'));
It will return a true
from an is_resource()
call, if the provided
argument to the method is a PHP resource. For example, \Mockery::type('float')
or Hamcrest’s floatValue()
and typeOf('float')
checks use is_float()
,
and \Mockery::type('callable')
or Hamcrest’s callable()
uses
is_callable()
.
The type()
matcher also accepts a class or interface name to be used in an
instanceof
evaluation of the actual argument. Hamcrest uses anInstanceOf()
.
A full list of the type checkers is available at php.net or browse Hamcrest’s function list in the Hamcrest code.
Complex Argument Validation¶
If we want to perform a complex argument validation, the on()
matcher is
invaluable. It accepts a closure (anonymous function) to which the actual
argument will be passed.
$mock = \Mockery::mock('MyClass');
$mock->shouldReceive("foo")
->with(\Mockery::on(closure));
If the closure evaluates to (i.e. returns) boolean true
then the argument is
assumed to have matched the expectation.
$mock = \Mockery::mock('MyClass');
$mock->shouldReceive('foo')
->with(\Mockery::on(function ($argument) {
if ($argument % 2 == 0) {
return true;
}
return false;
}));
$mock->foo(4); // matches the expectation
$mock->foo(3); // throws a NoMatchingExpectationException
Note
There is no Hamcrest version of the on()
matcher.
We can also perform argument validation by passing a closure to withArgs()
method. The closure will receive all arguments passed in the call to the expected
method and if it evaluates (i.e. returns) to boolean true
, then the list of
arguments is assumed to have matched the expectation:
$mock = \Mockery::mock('MyClass');
$mock->shouldReceive("foo")
->withArgs(closure);
The closure can also handle optional parameters, so if an optional parameter is missing in the call to the expected method, it doesn’t necessary means that the list of arguments doesn’t match the expectation.
$closure = function ($odd, $even, $sum = null) {
$result = ($odd % 2 != 0) && ($even % 2 == 0);
if (!is_null($sum)) {
return $result && ($odd + $even == $sum);
}
return $result;
};
$mock = \Mockery::mock('MyClass');
$mock->shouldReceive('foo')->withArgs($closure);
$mock->foo(1, 2); // It matches the expectation: the optional argument is not needed
$mock->foo(1, 2, 3); // It also matches the expectation: the optional argument pass the validation
$mock->foo(1, 2, 4); // It doesn't match the expectation: the optional doesn't pass the validation
Note
In previous versions, Mockery’s with()
would attempt to do a pattern
matching against the arguments, attempting to use the argument as a
regular expression. Over time this proved to be not such a great idea, so
we removed this functionality, and have introduced Mockery::pattern()
instead.
If we would like to match an argument against a regular expression, we can use
the \Mockery::pattern()
:
$mock = \Mockery::mock('MyClass');
$mock->shouldReceive('foo')
->with(\Mockery::pattern('/^foo/'));
// Hamcrest equivalent
$mock->shouldReceive('foo')
->with(matchesPattern('/^foo/'));
The ducktype()
matcher is an alternative to matching by class type:
$mock = \Mockery::mock('MyClass');
$mock->shouldReceive('foo')
->with(\Mockery::ducktype('foo', 'bar'));
It matches any argument which is an object containing the provided list of methods to call.
Note
There is no Hamcrest version of the ducktype()
matcher.
Capturing Arguments¶
If we want to perform multiple validations on a single argument, the capture
matcher provides a streamlined alternative to using the on()
matcher.
It accepts a variable which the actual argument will be assigned.
$mock = \Mockery::mock('MyClass');
$mock->shouldReceive("foo")
->with(\Mockery::capture($bar));
This will assign any argument passed to foo
to the local $bar
variable to
then perform additional validation using assertions.
Note
The capture
matcher always evaluates to true
. As such, we should always
perform additional argument validation.
Additional Argument Matchers¶
The not()
matcher matches any argument which is not equal or identical to
the matcher’s parameter:
$mock = \Mockery::mock('MyClass');
$mock->shouldReceive('foo')
->with(\Mockery::not(2));
// Hamcrest equivalent
$mock->shouldReceive('foo')
->with(not(2));
anyOf()
matches any argument which equals any one of the given parameters:
$mock = \Mockery::mock('MyClass');
$mock->shouldReceive('foo')
->with(\Mockery::anyOf(1, 2));
// Hamcrest equivalent
$mock->shouldReceive('foo')
->with(anyOf(1,2));
notAnyOf()
matches any argument which is not equal or identical to any of
the given parameters:
$mock = \Mockery::mock('MyClass');
$mock->shouldReceive('foo')
->with(\Mockery::notAnyOf(1, 2));
Note
There is no Hamcrest version of the notAnyOf()
matcher.
subset()
matches any argument which is any array containing the given array
subset:
$mock = \Mockery::mock('MyClass');
$mock->shouldReceive('foo')
->with(\Mockery::subset(array(0 => 'foo')));
This enforces both key naming and values, i.e. both the key and value of each actual element is compared.
Note
There is no Hamcrest version of this functionality, though Hamcrest can check
a single entry using hasEntry()
or hasKeyValuePair()
.
contains()
matches any argument which is an array containing the listed
values:
$mock = \Mockery::mock('MyClass');
$mock->shouldReceive('foo')
->with(\Mockery::contains(value1, value2));
The naming of keys is ignored.
hasKey()
matches any argument which is an array containing the given key
name:
$mock = \Mockery::mock('MyClass');
$mock->shouldReceive('foo')
->with(\Mockery::hasKey(key));
hasValue()
matches any argument which is an array containing the given
value:
$mock = \Mockery::mock('MyClass');
$mock->shouldReceive('foo')
->with(\Mockery::hasValue(value));