otezvikentiy/clock-mock

A PHP library for mocking date and time in tests

ClockMock

Slope s.r.l.

ClockMock provides a way for mocking the current timestamp used by PHP for \DateTime(Immutable) objects and date/time related functions. It requires the uopz extension (version >= 6.1.1).

This library is meant for development and testing only. It does not aim to propose a clock service to be used in production code, as we believe that you shouldn't need to do that when your only purpose is to mock the current time in testing code.

Why we built it

Here is an article that explains in depth how and why this library was built: link to the article.

TL;DR

• We were looking for a way to mock the native php date and time functions and classes without having to change our production code for it, and without having ot use any 3rd party library for handling dates/clocks.
• For this purpose, we were previously using the php-timecop extension but that never implemented support for PHP 7.4 onward.

Installation

You can install the library using Composer. Run the following command to install the latest version from Packagist:

composer require --dev slope-it/clock-mock

Note that, as this is not a tool intended for production, it should be required only for development (--dev flag).

Mocked functions/methods

• date()
• date_create()
• date_create_from_format()
• date_create_immutable()
• date_create_immutable_from_format()
• getdate()
• gettimeofday()
• gmdate()
• gmmktime()
• gmstrftime() (DEPRECATED starting from PHP 8.1)
• idate()
• localtime()
• microtime()
• mktime()
• strftime() (DEPRECATED starting from PHP 8.1)
• strtotime()
• time()
• unixtojd()
• DateTime::__construct
• DateTime::createFromFormat
• DateTimeImmutable::__construct
• DateTimeImmutable::createFromFormat
• $_SERVER['REQUEST_TIME']
• $_SERVER['REQUEST_TIME_FLOAT']

Usage

1. Stateful API

You can call ClockMock::freeze with a \DateTime or \DateTimeImmutable. Any code executed after it will use that specific date and time as the current timestamp. Call ClockMock::reset when done to restore real, current time.

Example:

<?php

use PHPUnit\Framework\TestCase;
use SlopeIt\ClockMock\ClockMock;

class MyTestCase extends TestCase
{
    public function test_something_using_stateful_mocking_api()
    {
        ClockMock::freeze(new \DateTime('1986-06-05'));
        
        // Code executed in here, until ::reset is called, will use the above date and time as "current"
        $nowYmd = date('Y-m-d');
        
        ClockMock::reset();
        
        $this->assertEquals('1986-06-05', $nowYmd);
    }
}

2. Stateless API

The library also provides a closure-based API that will execute the provided code at a specific point in time. This API does not need manually freezing or re-setting time, so it can be less error prone in some circumstances.

Example:

<?php

use PHPUnit\Framework\TestCase;
use SlopeIt\ClockMock\ClockMock;

class MyTestCase extends TestCase
{
    public function test_something_using_stateless_mocking_api()
    {
        $nowYmd = ClockMock::executeAtFrozenDateTime(new \DateTime('1986-06-05'), function () {
            // Code executed in here will use the above date and time as "current"
            return date('Y-m-d');
        });
        
        $this->assertEquals('1986-06-05', $nowYmd);
    }
}

How to contribute

• Did you find and fix any bugs in the existing code?
• Do you want to contribute a new feature, or a missing mock?
• Do you think documentation can be improved?

Under any of these circumstances, please fork this repo and create a pull request. We are more than happy to accept contributions!

Credits

• php-timecop, as ClockMock was inspired by it.
• ext-uopz, as ClockMock is just a very thin layer on top of the amazing uopz extension, which provides a very convenient way to mock any function or method, including the ones of the php stdlib, at runtime.