Rewrite to TypeScript

.github/workflows/main.yml

@@ -0,0 +1,22 @@
+name: CI
+on:
+  - push
+  - pull_request
+jobs:
+  test:
+    name: Node.js ${{ matrix.node-version }}
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        node-version:
+          - 18
+          - 16
+          - 14
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions/setup-node@v3
+        with:
+          node-version: ${{ matrix.node-version }}
+      - run: npm install
+      - run: npm test

.gitignore

@@ -1,4 +1,4 @@
 /dist
 /node_modules
-/yarn-*.log
 /coverage
+/package-lock.json

.tool-versions

@@ -0,0 +1 @@
+nodejs 18.15.0

CHANGELOG.md

@@ -1,9 +1,14 @@
 # Change Log
+
 All notable changes to this project will be documented in this file.
 
 The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
+## [0.2.0] - 2023-08-04
+
+- Rewritten to TypeScript.
+
 ## [0.1.1] - 2019-12-19
 
 - Do not use CoreJS builtins.

README.md

@@ -1,4 +1,4 @@
-# typecheck [![Build Status](https://travis-ci.org/umbrellio/typecheck.svg?branch=master)](https://travis-ci.org/umbrellio/typecheck) [![Coverage Status](https://coveralls.io/repos/github/umbrellio/typecheck/badge.svg?branch=master)](https://coveralls.io/github/umbrellio/typecheck?branch=master)
+# typecheck
 
 Simple, strict, extensible runtime type checker for JavaScript.
 

lib/index.ts

@@ -0,0 +1,28 @@
+import Type, { IType } from './type.js'
+
+import ArrayType from './types/array.js'
+import Sum from './types/sum.js'
+import Option from './types/option.js'
+import Struct from './types/struct.js'
+
+export default {
+  check(type: IType, value: unknown): boolean {
+    return type.__check(value)
+  },
+  Type,
+
+  String: new Type(
+    v => Object.prototype.toString.call(v) === '[object String]'
+  ),
+  Number: new Type(
+    v => Object.prototype.toString.call(v) === '[object Number]'
+  ),
+  Boolean: new Type(
+    v => Object.prototype.toString.call(v) === '[object Boolean]'
+  ),
+
+  Array: (type: IType) => new ArrayType(type),
+  Sum: (...types: unknown[]) => new Sum(types),
+  Option: (type: IType) => new Option(type),
+  Struct: (def: Record<string, IType>) => new Struct(def),
+}

lib/type.ts

@@ -0,0 +1,17 @@
+type TypeCheckFn = (value: unknown) => boolean
+
+export interface IType {
+  __check(value: unknown): boolean
+}
+
+export default class Type implements IType {
+  checker: TypeCheckFn
+
+  constructor(checker: TypeCheckFn) {
+    this.checker = checker
+  }
+
+  __check(value: unknown) {
+    return this.checker(value)
+  }
+}

lib/types/array.ts

@@ -0,0 +1,14 @@
+import { IType } from '../type.js'
+export default class TArray implements IType {
+  type: IType
+
+  constructor(type: IType) {
+    this.type = type
+  }
+
+  __check(value: unknown) {
+    if (!Array.isArray(value)) return false
+
+    return value.every(v => this.type.__check(v))
+  }
+}

lib/types/option.ts

@@ -0,0 +1,15 @@
+import { IType } from '../type.js'
+export default class Option implements IType {
+  type: IType
+
+  constructor(type: IType) {
+    this.type = type
+  }
+
+  __check(value: unknown) {
+    if (value === null) return true
+    if (value === undefined) return true
+
+    return this.type.__check(value)
+  }
+}

lib/types/struct.js → lib/types/struct.ts

@@ -1,14 +1,19 @@
-import { checkObjectType, hasOwnProperty } from '../util'
+import { hasOwnProperty, isObject } from '../util.js'
+import { IType } from '../type.js'
 
-export default class Struct {
-  constructor (definition) {
+export default class Struct implements IType {
+  definition: Record<string, IType>
+  definitionKeys: string[]
+  definitionKeysLen: number
+
+  constructor(definition: Record<string, IType>) {
     this.definition = definition
     this.definitionKeys = Object.keys(definition)
     this.definitionKeysLen = this.definitionKeys.length
   }
 
-  __check (value) {
-    if (!checkObjectType(value, 'Object')) return false
+  __check(value: unknown) {
+    if (!isObject(value)) return false
     if (this.definitionKeysLen !== Object.keys(value).length) return false
 
     for (let i = 0; i < this.definitionKeysLen; i += 1) {

lib/types/sum.ts

@@ -0,0 +1,20 @@
+import { isType } from '../util.js'
+import { IType } from '../type.js'
+
+export default class Sum implements IType {
+  values: unknown[]
+
+  constructor(values: unknown[]) {
+    this.values = values
+  }
+
+  __check(value: unknown) {
+    return this.values.some(v => {
+      if (isType(v)) {
+        return v.__check(value)
+      } else {
+        return v === value
+      }
+    })
+  }
+}

lib/util.ts

@@ -0,0 +1,13 @@
+import { IType } from './type.js'
+
+export function isObject(v: unknown): v is Record<string, unknown> {
+  return Object.prototype.toString.call(v) === '[object Object]'
+}
+
+export function isType(v: unknown): v is IType {
+  return isObject(v) && '__check' in v
+}
+
+export function hasOwnProperty(obj: Object, prop: string): boolean {
+  return Object.prototype.hasOwnProperty.call(obj, prop)
+}

package.json

@@ -1,13 +1,16 @@
 {
   "name": "@umbrellio/typecheck",
   "description": "Simple, strict, extensible runtime type checker for JavaScript",
-  "version": "0.1.1",
+  "version": "0.2.0",
   "author": "Alexander Komarov <[email protected]>",
   "repository": "umbrellio/typecheck",
   "license": "MIT",
-  "main": "dist/typecheck.cjs.js",
-  "modules": "dist/typecheck.es.js",
-  "unpkg": "dist/typecheck.iife.js",
+  "type": "module",
+  "exports": "./dist/index.js",
+  "types": "./dist/index.d.ts",
+  "engines": {
+    "node": ">=14.16 <=18"
+  },
   "files": [
     "dist"
   ],
@@ -18,27 +21,21 @@
     "type-check"
   ],
   "devDependencies": {
-    "@babel/core": "^7.6.0",
-    "@babel/preset-env": "^7.6.0",
-    "babel-eslint": "^10.0.3",
-    "babel-jest": "^24.9.0",
-    "core-js": "3",
-    "coveralls": "^3.0.6",
-    "eslint": "^6.3.0",
-    "eslint-config-umbrellio": "^5.0.1",
-    "eslint-plugin-import": "^2.18.2",
-    "eslint-plugin-node": "^10.0.0",
-    "eslint-plugin-prefer-object-spread": "^1.2.1",
-    "eslint-plugin-promise": "^4.2.1",
-    "jest": "^24.9.0",
-    "rollup": "^1.21.2",
-    "rollup-plugin-babel": "^4.3.3",
-    "rollup-plugin-node-resolve": "^5.2.0"
+    "ava": "^5.3.1",
+    "c8": "^8.0.1",
+    "ts-node": "^10.9.1",
+    "typescript": "^5.1.6"
   },
   "scripts": {
-    "build": "rollup -c",
-    "lint": "eslint lib/**/*.js",
-    "test": "jest",
-    "test:coverage": "jest --coverage"
+    "build": "tsc",
+    "test": "tsc --noEmit && c8 --reporter=lcov ava"
+  },
+  "ava": {
+    "extensions": {
+      "ts": "module"
+    },
+    "nodeArguments": [
+      "--loader=ts-node/esm"
+    ]
   }
 }