PHPUnit assertNotNull() Function

The assertNotNull() function is a builtin function in PHPUnit and is used to assert whether the variable is not (Null ). This assertion will return true in the case if the variable is Not (Null) else return false. In case of true the asserted test case got passed else test case got failed.

Syntax:

assertNotNull(mixed $variable[, string $message = ''])

Parameters: This function accepts two parameters as mentioned and described below:

• $Variable: This parameter has represented any type of variable.
• $message: This parameter takes string value. When the test case got failed this string message got displayed as error message.

Below examples illustrate the  assertNotNull() function in PHPUnit:

Example 1:

PHP

<?php
use PHPUnit\Framework\TestCase;

class GeeksPhpunitTestCase extends TestCase
{
    public function testNegativeTestcaseForassertNotNull()
    {
        $variable = Null;

        // Assert function to test whether given
        // variable is null or not
        $this->assertNotNull(
            $variable,
            "variable is null or not"
        );
    }
}

?>

Output:

PHPUnit 8.5.8 by Sebastian Bergmann and contributors.

F                                                  1 / 1 (100%)

Time: 86 ms, Memory: 10.00 MB

There was 1 failure:

1) GeeksPhpunitTestCase::testPositiveTestcaseForassertNotNull
variable is null or not
Failed asserting that null is not null.

/home/lovely/Documents/php/test.php:15

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

Example 2:

PHP

<?php
use PHPUnit\Framework\TestCase;

class GeeksPhpunitTestCase extends TestCase
{
    public function testPositiveTestcaseForassertNotNull()
    {
        $variable = "Null";

        // Assert function to test whether given
        // variable is empty or not
        $this->assertNotNull(
            $variable,
            "variable is null or not"
        );
    }
}

?>

Output:

PHPUnit 8.5.8 by Sebastian Bergmann and contributors.

.                                                  1 / 1 (100%)

Time: 88 ms, Memory: 10.00 MB

OK (1 test, 1 assertion)