effect-oxlint

library0.2.0jsnpmunverified

Effect-first library for writing oxlint custom lint rules. Current stable version: 0.2.0. Release cadence: irregular, with initial releases in early 2025. Key differentiators: provides typed errors, composable visitors, Option-safe AST matching, and Ref-based state without mutable variables, wrapping @oxlint/plugins in Effect idioms. Requires effect@^4.0.0-beta.57 as a peer dependency. Ideal for Effect ecosystem developers who want to write lint rules with Effect's effectful computation model.

devops testing

npm install effect-oxlint

github ↗package ↗

INSTALL

IMPORT

SIG · EFFECT-OXLINT

effect-oxlint

devopsjavascriptv0.2.0

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

Rule

✓ import { Rule } from 'effect-oxlint'

✗ const { Rule } = require('effect-oxlint')

ESM-only; named export from main module.

AST

✓ import { AST } from 'effect-oxlint'

✗ import AST from 'effect-oxlint'

Default import not available; must use named import.

Plugin

✓ import { Plugin } from 'effect-oxlint'

Named export for assembling plugins.

Diagnostic

✓ import { Diagnostic } from 'effect-oxlint'

Named export for building diagnostics.

Testing

✓ import { Testing } from 'effect-oxlint/testing'

✗ import { Testing } from 'effect-oxlint'

Testing module is in a subpath export 'effect-oxlint/testing'.

Defines a custom oxlint rule using Effect idioms, then assembles it into a plugin.

import * as Effect from 'effect/Effect'; import * as Option from 'effect/Option'; import { AST, Diagnostic, Rule, RuleContext } from 'effect-oxlint'; const noJsonParse = Rule.define({ name: 'no-json-parse', meta: Rule.meta({ type: 'suggestion', description: 'Use Schema for JSON decoding instead of JSON.parse' }), create: function* () { const ctx = yield* RuleContext; return { MemberExpression: (node) => Option.match( AST.matchMember(node, 'JSON', ['parse', 'stringify']), { onNone: () => Effect.void, onSome: (matched) => ctx.report( Diagnostic.make({ node: matched, message: 'Use Schema for JSON' }) ) } ) }; } }); export default Plugin.define({ name: 'my-effect-rules', rules: { 'no-json-parse': noJsonParse } });

Debug

Known issues

breakingIn v0.2.0, SourceCode.getText was split into getText() (whole file) and getNodeText(node) (node-specific). Old overload with Option<Node> removed.

fix

Use SourceCode.getText() for full file and SourceCode.getNodeText(node) for specific nodes.

affects: >=0.2.0

breakingRequires effect@^4.0.0-beta.57; incompatible with older effect versions.

fix

Update effect to ^4.0.0-beta.57.

affects: >=0.2.0

deprecatedThe previous Option<Node> overload of SourceCode.getText is removed; update to split functions.

fix

Use getNodeText for node-specific text extraction.

affects: >=0.2.0

breakingPeer dependency effect must be at least 4.0.0-beta.57; earlier betas fail.

fix

npm install effect@^4.0.0-beta.57

affects: >=0.2.0

Errors

Common errors & fixes

Cannot find module 'effect-oxlint' or its corresponding type declarations.

Missing or incompatible peer dependency 'effect'.

fix

Install effect@^4.0.0-beta.57 alongside effect-oxlint.

TypeError: (intermediate value) is not iterable

Using yield* in a non-generator context or missing Effect.run*.

fix

Ensure create is a generator function and wrap in Effect.runSync or similar.

Error: Cannot find module 'effect-oxlint/testing'

Importing Testing from wrong path; Testing is a subpath export.

fix

import { Testing } from 'effect-oxlint/testing'

Upgrade

Version history

0.2.0latest on npm

Audit

Dependencies

effectrequiredPeer dependency; provides Effect, Option, etc. for rule definitions

Agent activity

2 hits · last 30 days

node

Resources

githubhttps://github.com/mpsuesser/effect-oxlint ↗

packagehttps://www.npmjs.com/package/effect-oxlint ↗