A great thing about Tailwind CSS plugins being written in JavaScript is that they can be tested using tools like Jest.
Here's an example from https://github.com/opdavies/tailwindcss-plugin-jest-example (it may need updating to work with the latest Tailwind versions or to use the latest best practices):
Within the test, Tailwind can be run using PostCSS and generates styles based on a provided configuration, which is then checked against some expected output. If the generated styles match what was expected, the tests pass and the plugin is working as expected.
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