Add JSDoc based types

Author: wooorm

.gitignore

@@ -1,4 +1,5 @@
 .DS_Store
+*.d.ts
 *.log
 coverage/
 node_modules/

index.js

@@ -1,16 +1,49 @@
+/**
+ * @typedef {import('unist').Position} Position
+ * @typedef {import('unist').Point} Point
+ *
+ * @typedef {Partial<Point>} PointLike
+ *
+ * @typedef {Object} PositionLike
+ * @property {PointLike} [start]
+ * @property {PointLike} [end]
+ *
+ * @typedef {Object} NodeLike
+ * @property {PositionLike} [position]
+ */
+
 export var pointStart = point('start')
 export var pointEnd = point('end')
 
+/**
+ * Get the positional info of `node`.
+ *
+ * @param {NodeLike} [node]
+ * @returns {Position}
+ */
 export function position(node) {
   return {start: pointStart(node), end: pointEnd(node)}
 }
 
+/**
+ * Get the positional info of `node`.
+ *
+ * @param {'start'|'end'} type
+ */
 function point(type) {
   point.displayName = type
 
   return point
 
+  /**
+   * Get the positional info of `node`.
+   *
+   * @param {NodeLike} [node]
+   * @returns {Point}
+   */
   function point(node) {
+    /** @type {Point} */
+    // @ts-ignore looks like a point
     var point = (node && node.position && node.position[type]) || {}
 
     return {

package.json

@@ -25,22 +25,30 @@
   "sideEffects": false,
   "type": "module",
   "main": "index.js",
+  "types": "index.d.ts",
   "files": [
+    "index.d.ts",
     "index.js"
   ],
   "devDependencies": {
+    "@types/tape": "^4.0.0",
     "c8": "^7.0.0",
     "prettier": "^2.0.0",
     "remark-cli": "^9.0.0",
     "remark-preset-wooorm": "^8.0.0",
+    "rimraf": "^3.0.0",
     "tape": "^5.0.0",
+    "type-coverage": "^2.0.0",
+    "typescript": "^4.0.0",
     "xo": "^0.38.0"
   },
   "scripts": {
+    "prepack": "npm run build && npm run format",
+    "build": "rimraf \"*.d.ts\" && tsc && type-coverage",
     "format": "remark . -qfo && prettier . -w --loglevel warn && xo --fix",
     "test-api": "node test.js",
     "test-coverage": "c8 --check-coverage --branches 100 --functions 100 --lines 100 --statements 100 --reporter lcov node test.js",
-    "test": "npm run format && npm run test-coverage"
+    "test": "npm run build && npm run format && npm run test-coverage"
   },
   "prettier": {
     "tabWidth": 2,
@@ -62,5 +70,10 @@
     "plugins": [
       "preset-wooorm"
     ]
+  },
+  "typeCoverage": {
+    "atLeast": 100,
+    "detail": true,
+    "strict": true
   }
 }

tsconfig.json

@@ -0,0 +1,15 @@
+{
+  "include": ["*.js"],
+  "compilerOptions": {
+    "target": "ES2020",
+    "lib": ["ES2020"],
+    "module": "ES2020",
+    "moduleResolution": "node",
+    "allowJs": true,
+    "checkJs": true,
+    "declaration": true,
+    "emitDeclarationOnly": true,
+    "allowSyntheticDefaultImports": true,
+    "skipLibCheck": true
+  }
+}