Question 1

How do I debug jscodeshift transforms in VSCode?

Accepted Answer

Configure VSCode's launch.json with the provided debug setup, which uses jscodeshift's --dry and --print flags to run transforms without modifying files, allowing breakpoints and inspection in the IDE's debug console.

Question 2

jscodeshift vs Babel plugin for code transformations?

Accepted Answer

jscodeshift is better for batch, file-based transformations across entire projects with its CLI and collection API, while Babel plugins are ideal for compile-time AST manipulation within a build pipeline. jscodeshift preserves formatting, whereas Babel focuses on output optimization.

Question 3

How to write a jscodeshift transform for migrating to React hooks?

Accepted Answer

Start by using the jscodeshift API to find and replace class components with functional components, leveraging built-in methods like .find() for JSX elements. Reference example codemods from react-codemod for patterns and test with Jest utilities.

Question 4

Can jscodeshift handle TypeScript decorators?

Accepted Answer

Yes, by setting the parser to 'ts' or 'tsx' and ensuring the transform accounts for TypeScript-specific AST nodes. However, complex decorator logic may require custom handling due to parser limitations.

Question 5

How to ignore node_modules when running jscodeshift?

Accepted Answer

Use the --gitignore flag to automatically exclude files matching .gitignore patterns, or specify custom globs with --ignore-pattern for more control over ignored directories and files.

Question 6

What's the difference between jscodeshift and recast?

Accepted Answer

jscodeshift is a wrapper around recast that adds a fluent, collection-based API for easier AST manipulation, while recast is a lower-level AST-to-AST transform tool focused on preserving code style. jscodeshift simplifies common tasks but depends on recast for parsing and printing.

jscodeshift

What is jscodeshift?

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