Lint rules

@logtape/lint provides lint rules for ESLint (v8 and v9), Oxlint, and Deno Lint that detect common LogTape usage mistakes at development time.

Available rules

Rule	Default severity	Fix
no-message-interpolation	error	no
prefer-lazy-evaluation	warn	yes
no-unawaited-log	error	yes (conditional)
require-meta-sink	warn	no

Installation

Deno

deno add jsr:@logtape/lint

npm

npm add --save-dev @logtape/lint

pnpm

pnpm add --save-dev @logtape/lint

Yarn

yarn add --dev @logtape/lint

Bun

bun add --dev @logtape/lint

ESLint configuration

@logtape/lint ships with a ready-made recommended flat config preset for ESLint v9. Import the preset and spread it into your eslint.config.js (or eslint.config.mjs):

import logtape from "@logtape/lint/eslint";

export default [
  // ...other configs
  logtape.configs.recommended,
];

The preset activates all four rules with their default severities (see the table above).

For manual configuration, import the plugin and wire rules yourself:

import logtape from "@logtape/lint/eslint";

export default [
  {
    plugins: { "@logtape": logtape },
    rules: {
      "@logtape/no-message-interpolation": "error",
      "@logtape/prefer-lazy-evaluation": "warn",
      "@logtape/no-unawaited-log": "error",
      "@logtape/require-meta-sink": "warn",
    },
  },
];

Oxlint configuration

@logtape/lint rules follow the same plugin API as ESLint, so they work with Oxlint's ESLint-compatible plugin interface. Add the plugin to your .oxlintrc.json:

{
  "jsPlugins": [
    { "name": "@logtape", "specifier": "@logtape/lint/eslint" }
  ],
  "rules": {
    "@logtape/no-message-interpolation": "error",
    "@logtape/prefer-lazy-evaluation": "warn",
    "@logtape/no-unawaited-log": "error",
    "@logtape/require-meta-sink": "warn"
  }
}

Deno Lint configuration

WARNING

The Deno Lint plugin API is experimental (unstable). This plugin requires Deno 2.2.0 or later with the "unstable": ["lint"] option in deno.json.

Add the plugin to your deno.json and list the rules you want to enable:

{
  "unstable": ["lint"],
  "lint": {
    "plugins": ["jsr:@logtape/lint/deno"],
    "rules": {
      "include": [
        "logtape/no-message-interpolation",
        "logtape/prefer-lazy-evaluation",
        "logtape/no-unawaited-log",
        "logtape/require-meta-sink"
      ]
    }
  }
}

Then run deno lint as usual.