PHPunit | assertNotEquals() Function

The assertNotEquals() function is a builtin function in PHPUnit and is used to assert the actual obtained value to be not-equals to expected value. This assertion will return true in the case if the expected value is not-equals to actual value else returns false. In case of true the asserted test case got passed else test case got failed. Syntax:

assertNotEquals( 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 assertNotEquals() function in PHPUnit: Program 1: php

<?php
use PHPUnit\Framework\TestCase;

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

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

?>

Output:

PHPUnit 8.2.5 by Sebastian Bergmann and contributors.

F                                                                   1 / 1 (100%)

Time: 67 ms, Memory: 10.00 MB

There was 1 failure:

1) GeeksPhpunitTestCase::testNegativeTestcaseForAssertNotEquals
actual value is equals to expected
Failed asserting that 'geeks' is not equal to 'geeks'.

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

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

Program 2: php

<?php
use PHPUnit\Framework\TestCase;

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

        // Assert function to test whether expected
        // value is unequal to actual or not
        $this->assertNotEquals(
            $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, assertNotEquals() is supported by phpunit 7 and above.