PHPUnit assertNotIsWritable() Function

The assertNotIsWritable() function is a builtin function in PHPUnit and is used to assert whether the assertNotIswritable specified that filename is not writable. This assertion will return true in the case if either given file name Doesn't exist and is not writable else return false. In case of true the asserted test case got passed else test case got failed.

Syntax:

assertNotIsWritable(string $filename[, string $message = ''])

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

• $filename: This parameter is any type of string that denotes the file name.
• $message: This parameter takes a string value. When the test case got failed this string message got displayed as an error message.

Below examples illustrate the assertNotIsWritable() function in PHPUnit:

Examples 1:

<?php 
use PHPUnit\Framework\TestCase; 
  
class GeeksPhpunitTestCase extends TestCase 
{ 
    public function testNegativeTestcaseForassertNotIsWritable()
    { 
        $filename = "/home/lovely/Documents/php/phpunit"; 
  
        // Assert function to test whether given 
        // file name is not writable 
        $this->assertNotIsWritable(
            $filename, 
            "filename is not writable"
        ); 
    } 
} 
  
?> 

Output:

PHPUnit 8.5.8 by Sebastian Bergmann and contributors.

F                                                             1 / 1 (100%)

Time: 85 ms, Memory: 10.00 MB

There was 1 failure:

1) GeeksPhpunitTestCase::testNegativeTestcaseForassertNotIsWritable
filename is writable or Not
Failed asserting that "/home/lovely/Documents/php/phpunit" is not writable.

/home/lovely/Documents/php/test.php:16

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

Example 2:

<?php 
use PHPUnit\Framework\TestCase; 
  
class GeeksPhpunitTestCase extends TestCase 
{ 
    public function testPositiveTestcaseForassertNotIsWritable()
    { 
        $filename = "/home/lovely/Documents/php/phpunit/geeksforgeeks"; 
  
        // Assert function to test whether given 
        // file name is not writable 
        $this->assertNotIsWritable(
            $filename, 
            "filename is writable or not"
        ); 
    } 
} 
  
?> 

Output:

 PHPUnit 8.5.8 by Sebastian Bergmann and contributors.

.                                                 1 / 1 (100%)

Time: 87 ms, Memory: 10.00 MB

OK (1 test, 1 assertion)