How to measure code coverage with PHPUnit?

To measure code coverage with PHPUnit, you can follow these steps:

Install PHPUnit: If you haven't already, install PHPUnit globally by running the following command in your terminal:

composer global require phpunit/phpunit

Instrument your code: In order to measure code coverage, PHPUnit needs to instrument your code. To do this, you need to modify your phpunit.xml configuration file. Add or modify the <logging> section as follows:

<phpunit ...>
    ...
    <logging>
        <log type="coverage-html" target="coverage/" title="Code Coverage"/>
        <log type="coverage-clover" target="coverage.xml"/>
    </logging>
    ...
</phpunit>

This will generate an HTML report in the coverage/ directory and a Clover XML report in coverage.xml.

Run PHPUnit: Run PHPUnit with coverage enabled by executing the following command in your terminal:

phpunit --coverage-html coverage/

This command will run your tests and generate an HTML coverage report in the coverage/ directory. You can open the index.html file in your browser to view the report.

Analyze the coverage report: The generated HTML report will provide a comprehensive overview of the code coverage. It will show the percentage of code covered for each file. You can navigate through the report to identify areas where coverage is lacking and prioritize writing tests for those parts of your codebase.

Additionally, the Clover XML report can be used by other tools for further analysis or integration with build systems.

Note: PHPUnit's code coverage feature relies on the Xdebug extension being installed and enabled. Ensure that Xdebug is correctly installed and configured on your system for accurate code coverage measurements.

That's it! You have now set up code coverage measurement with PHPUnit and can use the generated reports to identify areas for improvement in your test suite.