Transformers - codemods in disguise

on YouTube ↗36m

" summary

A concrete example: a codemod is written to convert badFunction → goodFunction across a large Ember codebase, handling the simple callback case and the object+string case by constructing an arrow function that calls obj.success rather than relying on fragile regex. The workflow uses jscodeshift + AST Explorer + recast (parsers: Babel/Esprima), proves regex is insufficient, and becomes runnable via npx with a shared toolchain (RWJ blue slash code Matt CLI) that auto-generates input/output docs and tests.

AI-written summary · about

" chapters (7)

1. 0:00Introduction
2. 2:07Story of a feature developer
3. 8:48Excuses for not refactoring
4. 14:58Enter JSCodeshift
5. 21:15Live codemod demo
6. 32:04Codemod CLI tool
7. 34:54Conclusion and thanks

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