What are the potential pitfalls of testing private methods in PHP, and how can they be avoided?

Testing private methods in PHP can lead to tightly coupled tests, making it harder to refactor the code in the future. To avoid this, focus on testing the public API of your classes, as private methods are implementation details that should be covered by testing the public methods that use them. 

// Instead of testing private methods directly, focus on testing the public methods that use them

class MyClass
{
    private function privateMethod($input)
    {
        // implementation details
    }

    public function publicMethod($input)
    {
        // use privateMethod here
        $output = $this->privateMethod($input);
        return $output;
    }
}

// Test the public method instead of the private method

Keywords

private methods testing PHP visibility reflection

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