How to use assertions to check conditions in PHPUnit tests?

To use assertions to check conditions in PHPUnit tests, follow these steps:

Start by importing the necessary PHPUnit classes at the top of your test class file, such as:

use PHPUnit\Framework\TestCase;

class MyTest extends TestCase
{
    // ...
}

Inside your test methods, you can use various assertion methods provided by PHPUnit to check conditions. Here are some commonly used assertions:

To check if an expected value matches an actual value, use the assertEquals() method:

$this->assertEquals($expected, $actual);

To check if two variables refer to the exact same object, use the assertSame() method:

$this->assertSame($expected, $actual);

$this->assertTrue($condition);

$this->assertFalse($condition);

To check if an array contains a specific value, use the assertContains() method:

$this->assertContains($needle, $haystack);

To check if an array does not contain a specific value, use the assertNotContains() method:

$this->assertNotContains($needle, $haystack);

There are many more assertion methods available in PHPUnit, such as assertGreaterThan(), assertLessThan(), assertArrayHasKey(), etc. You can choose the appropriate one based on your specific testing needs.