Add JSDoc based types

.gitignore

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

build.js

@@ -4,30 +4,44 @@ import {bail} from 'bail'
 import concat from 'concat-stream'
 import unified from 'unified'
 import parse from 'rehype-parse'
+// @ts-ignore remove when typed
 import $ from 'hast-util-select'
+// @ts-ignore remove when typed
 import toString from 'hast-util-to-string'
 
 var endpoint =
   'https://www.readabilityformulas.com/articles/spache-formula-word-list.php'
 
 https.get(endpoint, onresponse)
 
+/**
+ * @param {import('http').IncomingMessage} response
+ */
 function onresponse(response) {
   response.pipe(concat(onconcat)).on('error', bail)
 }
 
+/**
+ * @param {Buffer} buf
+ */
 function onconcat(buf) {
   var tree = unified().use(parse).parse(buf)
 
   var values = $.selectAll('td p', tree)
-    .map((d) => toString(d))
+    .map((/** @type {import('hast').Element} */ d) => toString(d))
     .join('|')
     .replace(/\\/g, "'")
     .trim()
     .split(/\s*\|\s*/g)
     .filter(Boolean)
-    .map((d) => d.toLowerCase())
-    .filter((d, index, all) => all.indexOf(d) === index)
+    .map((/** @type {string} */ d) => d.toLowerCase())
+    .filter(
+      (
+        /** @type {string} */ d,
+        /** @type {number} */ index,
+        /** @type {Array.<string>} */ all
+      ) => all.indexOf(d) === index
+    )
     .sort()
 
   fs.writeFile(

package.json

@@ -21,29 +21,40 @@
   "sideEffects": false,
   "type": "module",
   "main": "index.js",
+  "types": "index.d.ts",
   "files": [
+    "index.d.ts",
     "index.js"
   ],
   "devDependencies": {
+    "@types/concat-stream": "^1.0.0",
+    "@types/hast": "^2.0.0",
+    "@types/node": "^14.0.0",
+    "@types/tape": "^4.0.0",
     "bail": "^2.0.0",
-    "c8": "^7.7.0",
+    "c8": "^7.0.0",
     "concat-stream": "^2.0.0",
     "hast-util-select": "^4.0.0",
     "hast-util-to-string": "^1.0.0",
     "prettier": "^2.0.0",
     "rehype-parse": "^7.0.0",
     "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",
     "unified": "^9.0.0",
     "xo": "^0.38.0"
   },
   "scripts": {
+    "prepack": "npm run build && npm run format",
+    "build": "rimraf \"*.d.ts\" && tsc && type-coverage",
     "generate": "node build",
     "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,
@@ -65,5 +76,10 @@
     "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
+  }
+}