@triggery/codemod

Codemods that mechanically migrate React/Redux side-effect code to Triggery's event → conditions → actions model. Powered by ts-morph.

pnpm add -D @triggery/codemod

CLI

# Pull a useEffect block out of a component into a *.trigger.ts file.
npx triggery-codemod extract-trigger --name new-message src/Chat.tsx

# Generate one trigger per RTK listenerMiddleware.startListening({ actionCreator, effect }).
npx triggery-codemod migrate-from-listener-middleware src/store/middleware.ts

Add --dry-run to preview without writing.

Programmatic API

import { extractTrigger, migrateFromListenerMiddleware } from '@triggery/codemod';

extractTrigger({ file: 'src/Chat.tsx', name: 'new-message' });

migrateFromListenerMiddleware({ file: 'src/store/middleware.ts' });

What each codemod does (and what it leaves to you)

extract-trigger

Reads the first useEffect(() => { … }, []) in the file and writes a sibling <name>.trigger.ts containing a stub createTrigger({…, handler() { /* original body */ } }). The component is rewritten to call useEvent(<name>Trigger, '<event-name>') instead.

The codemod intentionally does not:

• Infer the events / conditions / actions schema generic — you write it.
• Move closure-captured state into typed conditions — refactor by hand.
• Touch cleanup functions or effects with conditional deps — handle manually.

migrate-from-listener-middleware

For each startListening({ actionCreator, effect }) call in the file, generates one <event-name>.trigger.ts. The effect body is dropped verbatim into the new trigger's handler with a // TODO: refactor dispatch/getState into actions/conditions marker.

Other listenerMiddleware shapes (matcher, predicate, type) are detected but skipped — they need human review.

Why ts-morph (and not jscodeshift / babel)?

ts-morph is the TypeScript Compiler API with a nicer surface. It speaks JSX and the same type system the rest of Triggery is built on. The codemods produce TypeScript output, so type-aware AST work would be a regression with jscodeshift's recast-based round-trip.

Documentation

Full documentation, recipes and API reference at https://triggeryjs.github.io/packages/codemod/.

Related packages

• @triggery/eslint-plugin — Lint rules that catch issues this codemod can't repair.
• @triggery/cli — triggery scaffold trigger for greenfield files.

See the full package list in the repo README.

License

MIT © Aleksey Skhomenko