WordPress contributor teams have shipped several new tools for theme developers in the past couple weeks, which have the potential to raise the quality of new themes coming into the ecosystem. The Theme Sniffer plugin is a new effort from the Theme Review team that uses custom sniffs for PHP_CodeSniffer to test a theme against WordPress coding standards and check for PHP version compatibility.
The plugin is useful for both theme reviewers and developers who want to get their themes approved for the WordPress.org directory. It includes several optional standards to test against beyond the ruleset for theme review requirements. Passing the Theme Sniffer checks is not required for themes entering the directory but reviewers can use the plugin to speed the process up.
The Accessibility Team also published a new tool called WP Theme Auditor that runs Axe tests against a theme for automated accessibility feedback. Axe is an open source library and testing engine created by the accessibility experts at Deque. The WP Theme Auditor package can be installed into a theme’s root directory. Developers can then add test cases. Examples are available in the project’s README file. The tests are run against http://one.wordpress.test by default but developers can specify a different test environment URL.
The Accessibility team plans to expand the test cases in the tool to include all the content from the current Theme Unit Test Data package. In the most recent team meeting, they decided to recommend WP Theme Auditor as a WordPress testing tool and plan to post more details about it on the make.wordpress.org/accessibility blog.