PHPunit | assertEquals() Function

The assertEquals() function is a builtin function in PHPUnit and is used to assert whether the actual obtained value is equals to expected value or not. This assertion will return true in the case if the expected value is the same as the actual value else returns false. In case of true the asserted test case got passed else test case got failed.

Syntax:

assertEquals( mixed $expected, mixed $actual, string $message = '' )

Parameters: This function accepts three parameters as shown in the above syntax. The parameters are described below:

• $expected: This parameter is of any type which represent the expected data.
• $actual: This parameter is of any type which represent the actual data.
• $message: This parameter takes string value. When the testcase got failed this string message got displayed as error message.

Below programs illustrate the assertEquals() function in PHPUnit:

Program 1:

<?php
use PHPUnit\Framework\TestCase;

class GeeksPhpunitTestCase extends TestCase
{
    public function testNegativeTestcaseForAssertEquals()
    {
        $expected = "geeks";
        $actual = "Geeks";

        // Assert function to test whether expected
        // value is equal to actual or not
        $this->assertEquals(
            $expected,
            $actual,
            "actual value is not equals to expected"
        );
    }
}

?>

Output:

PHPUnit 8.2.5 by Sebastian Bergmann and contributors.

F                                                                   1 / 1 (100%)

Time: 64 ms, Memory: 10.00 MB

There was 1 failure:

1) GeeksPhpunitTestCase::testNegativeTestcaseForAssertEquals
actual value is not equals to expected
Failed asserting that two strings are equal.
--- Expected
+++ Actual
@@ @@
-'geeks'
+'Geeks'

/home/shivam/Documents/geeks/phpunit/abc.php:15

FAILURES!
Tests: 1, Assertions: 1, Failures: 1.

Program 2:

<?php
use PHPUnit\Framework\TestCase;

class GeeksPhpunitTestCase extends TestCase
{
    public function testPositiveTestcaseForAssertEquals()
    {
        $expected = "geeks";
        $actual = "geeks";

        // Assert function to test whether expected
        // value is equal to actual or not
        $this->assertEquals(
            $expected,
            $actual,
            "actual value is not equals to expected"
        );
    }
}

?>

Output:

PHPUnit 8.2.5 by Sebastian Bergmann and contributors.

.                                                                   1 / 1 (100%)

Time: 67 ms, Memory: 10.00 MB

OK (1 test, 1 assertion)

Note: To run testcases with phpunit follow steps from here. Also, assertEquals() is supported by phpunit 7 and above.