PHPUnit | assertStringNotContainsString() Function

The assertStringNotContainsString() function is a builtin function in PHPUnit and is used to assert a string doesn’t containing a substring. This assertion will return true in the case if the string doesn’t contain the substring as a substring else returns false and in case of true the asserted test case got passed else test case got failed.

Syntax:

assertStringNotContainsString(string $substring, string $string, string $message = ''])

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

• $substring: This parameter represents the string to be substring of given string.
• $string: This parameter is a string for which the assert function will check whether it contains substring or not.
• $message: This parameter takes string value. When the testcase got failed this string message got displayed as error message.

Below programs illustrate the assertStringNotContainsString() function in PHPUnit:

Program 1:

<?php
use PHPUnit\Framework\TestCase;

class GeeksPhpunitTestCase extends TestCase
{
    public function testNegativeTestcaseForAssertStringNotContainsString()
    {
        $testString = "geeksforgeek";
        $substring = "geeks";

        // Assert function to test whether 'geeks' is a
        // substring of testString
        $this->assertStringNotContainsString($substring, $testString,
                          "testString  contains 'geeks' as substring") ;
    }
}

?>

Output:

PHPUnit 8.2.5 by Sebastian Bergmann and contributors.

F                                                                   1 / 1 (100%)

Time: 72 ms, Memory: 10.00 MB

There was 1 failure:

1) GeeksPhpunitTestCase::testNegativeTestcaseForAssertStringNotContainsString
testString  contains 'geeks' as substring
Failed asserting that 'geeksforgeek' does not contain "geeks".

/home/shivam/Documents/geeks/phpunit/abc.php:11

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

Program 2:

<?php
use PHPUnit\Framework\TestCase;

class GeeksPhpunitTestCase extends TestCase
{
    public function testPositiveTestcaseForAssertStringNotContainsString()
    {
        $testString = "geekforgeek";
        $substring = "geeks";

        // Assert function to test whether 'geeks' is a
        // substring of testString
        $this->assertStringNotContainsString($substring, $testString,
                        "testString contains 'geeks' as substring") ;
    }
}

?>

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, assertStringNotContainsString() is supported by phpunit 7 and above.