webmozart/assert

Assertions to validate method input/output with nice error messages.

1.2.0 2016-11-23 20:04 UTC

README

Build Status Build status Latest Stable Version Total Downloads Dependency Status

Latest release: 1.2.0

PHP >= 5.3.9

This library contains efficient assertions to test the input and output of your methods. With these assertions, you can greatly reduce the amount of coding needed to write a safe implementation.

All assertions in the Assert class throw an \InvalidArgumentException if they fail.

FAQ

What's the difference to beberlei/assert?

This library is heavily inspired by Benjamin Eberlei's wonderful assert package, but fixes a usability issue with error messages that can't be fixed there without breaking backwards compatibility.

This package features usable error messages by default. However, you can also easily write custom error messages:

Assert::string($path, 'The path is expected to be a string. Got: %s');

In beberlei/assert, the ordering of the %s placeholders is different for every assertion. This package, on the contrary, provides consistent placeholder ordering for all assertions:

  • %s: The tested value as string, e.g. "/foo/bar".
  • %2$s, %3$s, ...: Additional assertion-specific values, e.g. the minimum/maximum length, allowed values, etc.

Check the source code of the assertions to find out details about the additional available placeholders.

Installation

Use Composer to install the package:

$ composer require webmozart/assert

Example

use Webmozart\Assert\Assert;

class Employee
{
    public function __construct($id)
    {
        Assert::integer($id, 'The employee ID must be an integer. Got: %s');
        Assert::greaterThan($id, 0, 'The employee ID must be a positive integer. Got: %s');
    }
}

If you create an employee with an invalid ID, an exception is thrown:

new Employee('foobar');
// => InvalidArgumentException: 
//    The employee ID must be an integer. Got: string

new Employee(-10);
// => InvalidArgumentException: 
//    The employee ID must be a positive integer. Got: -10

Assertions

The Assert class provides the following assertions:

Type Assertions

Method Description
string($value, $message = '') Check that a value is a string
stringNotEmpty($value, $message = '') Check that a value is a non-empty string
integer($value, $message = '') Check that a value is an integer
integerish($value, $message = '') Check that a value casts to an integer
float($value, $message = '') Check that a value is a float
numeric($value, $message = '') Check that a value is numeric
boolean($value, $message = '') Check that a value is a boolean
scalar($value, $message = '') Check that a value is a scalar
object($value, $message = '') Check that a value is an object
resource($value, $type = null, $message = '') Check that a value is a resource
isCallable($value, $message = '') Check that a value is a callable
isArray($value, $message = '') Check that a value is an array
isTraversable($value, $message = '') Check that a value is an array or a \Traversable
isInstanceOf($value, $class, $message = '') Check that a value is an instanceof a class
notInstanceOf($value, $class, $message = '') Check that a value is not an instanceof a class

Comparison Assertions

Method Description
true($value, $message = '') Check that a value is true
false($value, $message = '') Check that a value is false
null($value, $message = '') Check that a value is null
notNull($value, $message = '') Check that a value is not null
isEmpty($value, $message = '') Check that a value is empty()
notEmpty($value, $message = '') Check that a value is not empty()
eq($value, $value2, $message = '') Check that a value equals another (==)
notEq($value, $value2, $message = '') Check that a value does not equal another (!=)
same($value, $value2, $message = '') Check that a value is identical to another (===)
notSame($value, $value2, $message = '') Check that a value is not identical to another (!==)
greaterThan($value, $value2, $message = '') Check that a value is greater than another
greaterThanEq($value, $value2, $message = '') Check that a value is greater than or equal to another
lessThan($value, $value2, $message = '') Check that a value is less than another
lessThanEq($value, $value2, $message = '') Check that a value is less than or equal to another
range($value, $min, $max, $message = '') Check that a value is within a range
oneOf($value, array $values, $message = '') Check that a value is one of a list of values

String Assertions

You should check that a value is a string with Assert::string() before making any of the following assertions.

Method Description
contains($value, $subString, $message = '') Check that a string contains a substring
startsWith($value, $prefix, $message = '') Check that a string has a prefix
startsWithLetter($value, $message = '') Check that a string starts with a letter
endsWith($value, $suffix, $message = '') Check that a string has a suffix
regex($value, $pattern, $message = '') Check that a string matches a regular expression
alpha($value, $message = '') Check that a string contains letters only
digits($value, $message = '') Check that a string contains digits only
alnum($value, $message = '') Check that a string contains letters and digits only
lower($value, $message = '') Check that a string contains lowercase characters only
upper($value, $message = '') Check that a string contains uppercase characters only
length($value, $length, $message = '') Check that a string has a certain number of characters
minLength($value, $min, $message = '') Check that a string has at least a certain number of characters
maxLength($value, $max, $message = '') Check that a string has at most a certain number of characters
lengthBetween($value, $min, $max, $message = '') Check that a string has a length in the given range
uuid($value, $message = '') Check that a string is a valid UUID

File Assertions

Method Description
fileExists($value, $message = '') Check that a value is an existing path
file($value, $message = '') Check that a value is an existing file
directory($value, $message = '') Check that a value is an existing directory
readable($value, $message = '') Check that a value is a readable path
writable($value, $message = '') Check that a value is a writable path

Object Assertions

Method Description
classExists($value, $message = '') Check that a value is an existing class name
subclassOf($value, $class, $message = '') Check that a class is a subclass of another
implementsInterface($value, $class, $message = '') Check that a class implements an interface
propertyExists($value, $property, $message = '') Check that a property exists in a class/object
propertyNotExists($value, $property, $message = '') Check that a property does not exist in a class/object
methodExists($value, $method, $message = '') Check that a method exists in a class/object
methodNotExists($value, $method, $message = '') Check that a method does not exist in a class/object

Array Assertions

Method Description
keyExists($array, $key, $message = '') Check that a key exists in an array
keyNotExists($array, $key, $message = '') Check that a key does not exist in an array
count($array, $number, $message = '') Check that an array contains a specific number of elements

Function Assertions

Method Description
throws($closure, $class, $message = '') Check that a function throws a certain exception. Subclasses of the exception class will be accepted.

Collection Assertions

All of the above assertions can be prefixed with all*() to test the contents of an array or a \Traversable:

Assert::allIsInstanceOf($employees, 'Acme\Employee');

Nullable Assertions

All of the above assertions can be prefixed with nullOr*() to run the assertion only if it the value is not null:

Assert::nullOrString($middleName, 'The middle name must be a string or null. Got: %s');

Authors

Contribute

Contributions to the package are always welcome!

Support

If you are having problems, send a mail to bschussek@gmail.com or shout out to @webmozart on Twitter.

License

All contents of this package are licensed under the MIT license.