Registry / testing / eslint-plugin-strict-null-checks

eslint-plugin-strict-null-checks

library0.1.3jsnpmunverified

ESLint plugin that reproduces TypeScript's strictNullChecks behavior as lint rules, enabling incremental migration from strictNullChecks: false to true. Version 0.1.3 (stable, low activity) depends on typescript >=3.9.4. Unlike native tsconfig strictNullChecks, allows warnings instead of errors and can be gradually applied per file via ESLint config. Requires @typescript-eslint/parser with project option pointing to a separate tsconfig with strictNullChecks: true.

testing

npm install eslint-plugin-strict-null-checks

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · ESLINT-PLUGIN-STRI

eslint-plugin-strict-null-checks

testingjavascriptv0.1.3

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.

plugin

✓ plugins: ['strict-null-checks']

✗ plugins: ['eslint-plugin-strict-null-checks']

In ESLint config, plugin names omit the eslint-plugin- prefix.

rule

✓ rules: { 'strict-null-checks/all': 'warn' }

✗ rules: { 'strict-null-checks': 'warn' }

The rule is namespaced with 'all' as the rule name.

parserOptions

✓ parserOptions: { project: './tsconfig.strictNullChecks.json' }

✗ parserOptions: { project: './tsconfig.json' }

Requires a separate tsconfig with strictNullChecks: true to avoid affecting the rest of the project.

Configure ESLint to gradually enforce strict null checks using a separate tsconfig.

// .eslintrc.js module.exports = { parser: '@typescript-eslint/parser', parserOptions: { project: './tsconfig.strictNullChecks.json', }, plugins: ['strict-null-checks'], rules: { 'strict-null-checks/all': 'warn', }, ignorePatterns: ['.eslintrc.js'], }; // tsconfig.strictNullChecks.json { "compilerOptions": { "strictNullChecks": true }, "include": ["src/**/*.ts", "src/**/*.tsx"] } // Then run: npx eslint src/

Debug

Known issues

breakingRequires a separate tsconfig file with strictNullChecks: true, which may conflict with existing project configuration.

fix

Create tsconfig.strictNullChecks.json and set parserOptions.project to that file.

affects: >=0.0.0

gotchaParsing error: "parserOptions.project" has been set for @typescript-eslint/parser. The file does not match your project config: .eslintrc.js. The file must be included in at least one of the projects provided.

fix

Add ignorePatterns: ['.eslintrc.js'] to your ESLint config, or include .eslintrc.js in tsconfig.strictNullChecks.json with allowJs: true.

affects: >=0.0.0

gotchaThe plugin only works with @typescript-eslint/parser, not the default Espree parser.

fix

Install @typescript-eslint/parser and set parser in ESLint config.

affects: >=0.0.0

breakingThe 'all' rule may produce false positives for code that intentionally uses null/undefined in ways TypeScript allows when strictNullChecks is off.

fix

Use warning level and manually review each violation before committing to fix.

affects: >=0.0.0

Errors

Common errors & fixes

Parsing error: "parserOptions.project" has been set for @typescript-eslint/parser. The file does not match your project config: .eslintrc.js.

ESLint config file is not covered by tsconfig.strictNullChecks.json.

fix

Add ignorePatterns: ['.eslintrc.js'] to ESLint config, or include the file in tsconfig.

Cannot find module 'eslint-plugin-strict-null-checks'

Plugin not installed.

fix

Run npm install eslint-plugin-strict-null-checks --save-dev

Configuration for rule 'strict-null-checks/all' is invalid: Unknown rule strict-null-checks/all

The plugin is not loaded in plugins section.

fix

Add 'strict-null-checks' to plugins array in ESLint config.

TypeError: Cannot read properties of undefined (reading 'getTypeArguments')

Incompatible @typescript-eslint/parser version or missing project.

fix

Ensure @typescript-eslint/parser is installed and parserOptions.project points to valid tsconfig.

Upgrade

Version history

0.1.3latest on npm

Audit

Dependencies

typescriptrequiredPeer dependency for TypeScript type checking

Agent activity

2 hits · last 30 days

node

Resources

githubhttps://github.com/JaroslawPokropinski/eslint-plugin-strict-null-check ↗

packageeslint-plugin-strict-null-checks ↗

homepagehttps://github.com/JaroslawPokropinski/eslint-plugin-strict-null-check#readme ↗