babel-plugin-tester is a utility for writing comprehensive tests for Babel plugins and presets. It simplifies the testing process by providing a structured way to define test cases, including support for fixtures, snapshots, and custom assertions. The tool is primarily designed for Jest but also works with other test runners like Mocha, Jasmine, and Vitest. It allows users to test both plugins and presets, offering options for configuration, setup/teardown functions, and output formatting. It’s ideal for developers working on Babel plugins or presets who want to ensure their transformations work as expected.