PHPUnit assertDirectoryIsWritable() Function

The assertDirectoryIsWritable() function is a builtin function in PHPUnit and is used to assert whether the directory specified is a directory or is writable. This assertion will return true in the case if either given directory path exists and is writable else return false. In case of true the asserted test case got passed else test case got failed.

Syntax:

assertDirectoryIsWritable(string $directory[, string $message = ''])

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

• $directory: This parameter is a string which denotes the directory path.
• $message: This parameter takes string value. When the testcase got failed this string message got displayed as error message.

Below examples illustrate the assertDirectoryIsWritable() function in PHPUnit:

Example 1:

<?php 
use PHPUnit\Framework\TestCase; 
  
class GeeksPhpunitTestCase extends TestCase 
{ 
    public function testNegativeTestcaseForAssertDirectoryIsWritable() 
    { 
        $directoryPath = "/home/lovely/Documents/writable"; 
  
        // Assert function to test whether given 
        // directory path exists and writable
        $this->assertDirectoryIsWritable( 
            $directoryPath, 
            "directoryPath exists and writable"
        ); 
    } 
} 
  
?> 

Output:

PHPUnit 8.5.8 by Sebastian Bergmann and contributors.

F                                                         1 / 1 (100%)

Time: 90 ms, Memory: 10.00 MB

There was 1 failure:

1) GeeksPhpunitTestCase::testNegativeTestcaseForAssertDirectoryIsWritable
directoryPath exists and writable
Failed asserting that directory "/home/lovely/Documents/writable" exists.

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

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

Example 2:

<?php 
use PHPUnit\Framework\TestCase; 
  
class GeeksPhpunitTestCase extends TestCase 
{ 
    public function testPositiveTestcaseForAssertDirectoryIsWritable() 
    { 
        $directoryPath = "/home/lovely/Documents"; 
  
        // Assert function to test whether given 
        // directory path exists and writable
        $this->assertDirectoryIsWritable( 
            $directoryPath, 
            "directoryPath exists and writable"
        ); 
    } 
} 
  
?> 

Output:

PHPUnit 8.5.8 by Sebastian Bergmann and contributors.

.                                             1 / 1 (100%)

Time: 89 ms, Memory: 10.00 MB

OK (1 test, 2 assertions)