Use ESM

Author: wooorm

.gitignore

@@ -1,8 +1,5 @@
 .DS_Store
 *.log
-.nyc_output/
 coverage/
 node_modules/
-hast-util-is-element.js
-hast-util-is-element.min.js
 yarn.lock

.prettierignore

@@ -1,5 +1,2 @@
 coverage/
-hast-util-is-element.js
-hast-util-is-element.min.js
-*.json
 *.md

convert.js

@@ -1,35 +1,107 @@
-'use strict'
-
-var convert = require('./convert')
-
-module.exports = isElement
-
-isElement.convert = convert
-
 // Check if if `node` is an `element` and whether it passes the given test.
-function isElement(node, test, index, parent, context) {
-  var check = convert(test)
+// eslint-disable-next-line max-params
+export function isElement(node, test, index, parent, context) {
+  var check = convertElement(test)
 
   if (
-    index != null &&
+    index !== undefined &&
+    index !== null &&
     (typeof index !== 'number' ||
       index < 0 ||
       index === Number.POSITIVE_INFINITY)
   ) {
     throw new Error('Expected positive finite index for child node')
   }
 
-  if (parent != null && (!parent.type || !parent.children)) {
+  if (
+    parent !== undefined &&
+    parent !== null &&
+    (!parent.type || !parent.children)
+  ) {
     throw new Error('Expected parent node')
   }
 
   if (!node || !node.type || typeof node.type !== 'string') {
     return false
   }
 
-  if ((parent == null) !== (index == null)) {
+  if (
+    (parent === undefined || parent === null) !==
+    (index === undefined || index === null)
+  ) {
     throw new Error('Expected both parent and index')
   }
 
   return check.call(context, node, index, parent)
 }
+
+export function convertElement(test) {
+  if (test === undefined || test === null) {
+    return element
+  }
+
+  if (typeof test === 'string') {
+    return tagNameFactory(test)
+  }
+
+  if (typeof test === 'object') {
+    return anyFactory(test)
+  }
+
+  if (typeof test === 'function') {
+    return callFactory(test)
+  }
+
+  throw new Error('Expected function, string, or array as test')
+}
+
+function anyFactory(tests) {
+  var index = -1
+  var checks = []
+
+  while (++index < tests.length) {
+    checks[index] = convertElement(tests[index])
+  }
+
+  return any
+
+  function any(...parameters) {
+    var index = -1
+
+    while (++index < checks.length) {
+      if (checks[index].call(this, ...parameters)) {
+        return true
+      }
+    }
+
+    return false
+  }
+}
+
+// Utility to convert a string a tag name check.
+function tagNameFactory(test) {
+  return tagName
+
+  function tagName(node) {
+    return element(node) && node.tagName === test
+  }
+}
+
+// Utility to convert a function check.
+function callFactory(test) {
+  return call
+
+  function call(node, ...parameters) {
+    return element(node) && Boolean(test.call(this, node, ...parameters))
+  }
+}
+
+// Utility to return true if this is an element.
+function element(node) {
+  return (
+    node &&
+    typeof node === 'object' &&
+    node.type === 'element' &&
+    typeof node.tagName === 'string'
+  )
+}

index.js

@@ -23,28 +23,25 @@
   "contributors": [
     "Titus Wormer <[email protected]> (https://wooorm.com)"
   ],
+  "sideEffects": false,
+  "type": "module",
+  "main": "index.js",
   "files": [
-    "convert.js",
     "index.js"
   ],
   "devDependencies": {
-    "browserify": "^17.0.0",
-    "nyc": "^15.0.0",
+    "c8": "^7.0.0",
     "prettier": "^2.0.0",
     "remark-cli": "^9.0.0",
     "remark-preset-wooorm": "^8.0.0",
     "tape": "^5.0.0",
-    "tinyify": "^3.0.0",
     "xo": "^0.38.0"
   },
   "scripts": {
     "format": "remark . -qfo && prettier . -w --loglevel warn && xo --fix",
-    "build-bundle": "browserify . -s hastUtilIsElement -o hast-util-is-element.js",
-    "build-mangle": "browserify . -s hastUtilIsElement -o hast-util-is-element.min.js -p tinyify",
-    "build": "npm run build-bundle && npm run build-mangle",
-    "test-api": "node test",
-    "test-coverage": "nyc --reporter lcov tape test.js",
-    "test": "npm run format && npm run build && npm run test-coverage"
+    "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"
   },
   "prettier": {
     "tabWidth": 2,
@@ -56,30 +53,11 @@
   },
   "xo": {
     "prettier": true,
-    "esnext": false,
-    "ignores": [
-      "hast-util-is-element.js"
-    ],
     "rules": {
-      "eqeqeq": [
-        "error",
-        "always",
-        {
-          "null": "ignore"
-        }
-      ],
-      "max-params": "off",
-      "no-eq-null": "off",
-      "unicorn/prefer-type-error": "off",
-      "unicorn/prefer-reflect-apply": "off"
+      "no-var": "off",
+      "prefer-arrow-callback": "off"
     }
   },
-  "nyc": {
-    "check-coverage": true,
-    "lines": 100,
-    "functions": 100,
-    "branches": 100
-  },
   "remarkConfig": {
     "plugins": [
       "preset-wooorm"

package.json

@@ -13,6 +13,9 @@
 
 ## Install
 
+This package is [ESM only](https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c):
+Node 12+ is needed to use it and it must be `import`ed instead of `require`d.
+
 [npm][]:
 
 ```sh
@@ -22,17 +25,20 @@ npm install hast-util-is-element
 ## Use
 
 ```js
-var is = require('hast-util-is-element')
+import {isElement} from 'hast-util-is-element'
 
-is({type: 'text', value: 'foo'}) // => false
+isElement({type: 'text', value: 'foo'}) // => false
 
-is({type: 'element', tagName: 'a'}, 'a') // => true
+isElement({type: 'element', tagName: 'a'}, 'a') // => true
 
-is({type: 'element', tagName: 'a'}, ['a', 'area']) // => true
+isElement({type: 'element', tagName: 'a'}, ['a', 'area']) // => true
 ```
 
 ## API
 
+This package exports the following identifiers: `isElement`, `convertElement`.
+There is no default export.
+
 ### `isElement(node[, test[, index, parent[, context]]])`
 
 Check if the given value is a (certain) [*element*][element].
@@ -71,7 +77,7 @@ A `node` that is not a node, or not an element, does not throw.
 
 `boolean?` — Whether `element` matches.
 
-### `isElement.convert(test)`
+### `convertElement(test)`
 
 Create a test function from `test`, that can later be called with a `node`,
 `index`, and `parent`.
@@ -81,8 +87,6 @@ where something else passes a compatible test.
 The created function is slightly faster because it expects valid input only.
 Therefore, passing invalid input, yields unexpected results.
 
-Can also be accessed with `require('hast-util-is-element/convert')`.
-
 ## Security
 
 `hast-util-is-element` does not change the syntax tree so there are no openings

readme.md

@@ -1,7 +1,5 @@
-'use strict'
-
-var test = require('tape')
-var isElement = require('.')
+import test from 'tape'
+import {isElement} from './index.js'
 
 test('isElement', function (t) {
   t.equal(isElement(), false, 'should return `false` without node')