Updates

.github/workflows/ci.yml

@@ -0,0 +1,67 @@
+name: CI
+
+on:
+  push:
+    branches: ['main']
+    tags: ['v*']
+  pull_request:
+    branches: ['*']
+
+  workflow_dispatch:
+
+concurrency:
+  group: ${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  validate:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: pnpm/action-setup@v4
+        with:
+          version: 10
+          run_install: false
+
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 22
+          cache: pnpm
+
+      - run: pnpm install
+
+      - run: pnpm validate
+
+      - uses: SonarSource/sonarqube-scan-action@v7.0.0
+        if: "!startsWith(github.ref, 'refs/tags/')"
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          SONAR_TOKEN: ${{ secrets.SONAR_TOKEN }}
+
+  publish:
+    runs-on: ubuntu-latest
+    if: startsWith(github.ref, 'refs/tags/v')
+    needs: validate
+    permissions:
+      id-token: write
+      contents: read
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: pnpm/action-setup@v4
+        with:
+          version: 10
+          run_install: false
+
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 22
+          cache: pnpm
+          registry-url: https://registry.npmjs.org
+
+      - run: npm install -g npm@11
+
+      - run: pnpm install
+
+      - run: npm publish --provenance

CLAUDE.md

@@ -0,0 +1,46 @@
+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Commands
+
+```bash
+pnpm build           # Clean and build with tsup (outputs dist/)
+pnpm lint            # ESLint with auto-fix
+pnpm typecheck       # TypeScript check (noEmit)
+pnpm test            # Runs vitest once
+pnpm test:watch      # Runs vitest watch mode
+pnpm test:coverage   # Runs tests with coverage
+pnpm validate        # Full validation: lint + typecheck + test:coverage + build + size
+```
+
+Run a single test file:
+```bash
+pnpm test test/arrays.spec.ts
+```
+
+Run tests matching a pattern:
+```bash
+pnpm test -t "should return true"
+```
+
+## Architecture
+
+Single-purpose library exporting one default function `equal(left, right)` that performs deep equality comparison.
+
+**Source structure:**
+- `src/index.ts` - Main `equal` function with specialized comparators for arrays, Maps, Sets, ArrayBuffers, and objects
+- `src/helpers.ts` - Type guard utilities (`isObject`, `isRegex`, etc.)
+- `src/types.ts` - TypeScript type definitions
+
+**Key implementation details:**
+- Circular references: Handled via WeakMap/WeakSet tracking to prevent infinite recursion in self-referential or cross-referential structures
+- React elements: Skips `_owner` property (contains circular refs) when `$$typeof` is present
+- NaN handling: `NaN === NaN` returns true
+- Comparison order: Reference equality → constructor match → type-specific comparison → valueOf/toString fallback → key-by-key recursion
+
+**Tests** are organized by data type in `test/*.spec.ts` (scalars, objects, arrays, dates, regex, functions, bigint, maps, sets, typed-arrays).
+
+## Build
+
+Uses `tsup` with dual output (CJS + ESM). Size limit: 1kB per format.

eslint.config.mjs

@@ -0,0 +1,15 @@
+import config from '@gilbarbara/eslint-config';
+import testingLibrary from '@gilbarbara/eslint-config/testing-library';
+import vitest from '@gilbarbara/eslint-config/vitest';
+
+export default [
+  ...config,
+  ...vitest,
+  ...testingLibrary,
+  {
+    files: ['**/?(*.)+(spec|test).[jt]s?(x)'],
+    rules: {
+      'no-console': 'off',
+    },
+  },
+];

package.json

@@ -32,43 +32,43 @@
     "typescript"
   ],
   "devDependencies": {
-    "@gilbarbara/eslint-config": "^0.5.4",
+    "@gilbarbara/eslint-config": "^1.0.4",
     "@gilbarbara/prettier-config": "^1.0.0",
-    "@gilbarbara/tsconfig": "^0.2.3",
-    "@size-limit/preset-small-lib": "^9.0.0",
-    "@types/node": "^20.8.4",
-    "@types/react": "^18.2.28",
-    "@types/react-dom": "^18.2.13",
-    "@types/react-test-renderer": "^18.0.3",
-    "@vitest/coverage-v8": "^0.34.6",
-    "del-cli": "^5.1.0",
-    "happy-dom": "^12.7.0",
-    "husky": "^8.0.3",
-    "is-ci-cli": "^2.2.0",
-    "jest-extended": "^4.0.2",
-    "react": "^18.2.0",
-    "react-test-renderer": "^18.2.0",
-    "repo-tools": "^0.2.2",
-    "size-limit": "^9.0.0",
-    "ts-node": "^10.9.1",
-    "tsup": "^7.2.0",
-    "typescript": "^5.2.2",
-    "vitest": "^0.34.6"
+    "@gilbarbara/tsconfig": "^1.0.0",
+    "@size-limit/preset-small-lib": "^12.0.0",
+    "@testing-library/react": "^16.3.2",
+    "@types/node": "^22.19.8",
+    "@types/react": "^19.2.10",
+    "@types/react-dom": "^19.2.3",
+    "@vitest/coverage-v8": "^4.0.18",
+    "del-cli": "^7.0.0",
+    "eslint": "^9.39.2",
+    "happy-dom": "^20.5.0",
+    "husky": "^9.1.7",
+    "jest-extended": "^7.0.0",
+    "prettier": "^3.8.1",
+    "react": "^19.2.4",
+    "react-dom": "^19.2.4",
+    "repo-tools": "^0.3.1",
+    "size-limit": "^12.0.0",
+    "ts-node": "^10.9.2",
+    "tsup": "^8.5.1",
+    "typescript": "^5.9.3",
+    "vitest": "^4.0.18"
   },
   "scripts": {
-    "build": "npm run clean && tsup",
+    "build": "pnpm clean && tsup",
     "watch": "tsup --watch",
     "clean": "del dist/*",
-    "test": "is-ci \"test:coverage\" \"test:watch\"",
-    "test:coverage": "TZ=UTC vitest run --coverage",
-    "test:watch": "TZ=UTC vitest watch",
+    "test": "vitest run",
+    "test:coverage": "vitest run --coverage",
+    "test:watch": "vitest watch",
     "lint": "eslint --fix src test",
-    "typecheck": "tsc",
+    "typecheck": "tsc --p test/tsconfig.json",
     "format": "prettier \"**/*.{css,graphql,js,json,jsx,less,md,mdx,scss,ts,tsx,yaml,yml}\" --write",
-    "validate": "npm run lint && npm run typecheck && npm run test:coverage && npm run build && npm run size",
+    "validate": "pnpm lint && pnpm typecheck && pnpm test:coverage && pnpm build && pnpm size",
     "size": "size-limit",
-    "prepublishOnly": "npm run validate",
-    "prepare": "husky install"
+    "prepare": "husky"
   },
   "tsup": {
     "cjsInterop": true,
@@ -83,11 +83,6 @@
     "sourcemap": true,
     "splitting": false
   },
-  "eslintConfig": {
-    "extends": [
-      "@gilbarbara/eslint-config"
-    ]
-  },
   "prettier": "@gilbarbara/prettier-config",
   "size-limit": [
     {