Use ESM

Author: wooorm

.gitignore

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

index.js

@@ -1,33 +1,20 @@
-'use strict'
+import nodeAssert from 'assert'
+import {inspect} from './inspect.js'
 
-var assert = require('assert')
-var array = require('x-is-array')
-var object = require('x-is-object')
-
-var inspect
-
-try {
-  // eslint-disable-next-line no-useless-concat
-  inspect = require('ut' + 'il').inspect
-} catch (_) {}
-
-exports = wrap(unist)
-module.exports = exports
-
-exports.parent = wrap(parent)
-exports.text = wrap(text)
-exports.void = wrap(empty)
-exports.wrap = wrap
+export var assert = wrap(assertNode)
+assert.parent = wrap(parent)
+assert.text = wrap(text)
+assert.void = wrap(empty)
 
 // Identifier to check if a value is seen.
 var ID = '__unist__'
 
 // List of specced properties.
-var defined = ['type', 'value', 'children', 'position']
+var defined = new Set(['type', 'value', 'children', 'position'])
 
 // Wrapper around `Node` which adds the current node (and parent, if available),
 // to the message.
-function wrap(fn) {
+export function wrap(fn) {
   return wrapped
 
   function wrapped(node, parent) {
@@ -50,43 +37,43 @@ function wrap(fn) {
 }
 
 // Assert.
-function unist(node) {
+function assertNode(node) {
   var type
   var children
   var value
   var key
   var index
   var length
 
-  assert.ok(object(node), 'node should be an object')
+  nodeAssert.ok(node === Object(node), 'node should be an object')
 
   type = node.type
   children = node.children
   value = node.value
 
-  assert.ok('type' in node, 'node should have a type')
-  assert.strictEqual(typeof type, 'string', '`type` should be a string')
-  assert.notStrictEqual(type, '', '`type` should not be empty')
+  nodeAssert.ok('type' in node, 'node should have a type')
+  nodeAssert.strictEqual(typeof type, 'string', '`type` should be a string')
+  nodeAssert.notStrictEqual(type, '', '`type` should not be empty')
 
-  if (value != null) {
-    assert.strictEqual(typeof value, 'string', '`value` should be a string')
+  if (value !== null && value !== undefined) {
+    nodeAssert.strictEqual(typeof value, 'string', '`value` should be a string')
   }
 
   position(node.position)
 
   for (key in node) {
-    if (!defined.includes(key)) {
+    if (!defined.has(key)) {
       vanilla(key, node[key])
     }
   }
 
-  if (children != null) {
-    assert.ok(array(children), '`children` should be an array')
+  if (children !== null && children !== undefined) {
+    nodeAssert.ok(Array.isArray(children), '`children` should be an array')
     index = -1
     length = children.length
 
     while (++index < length) {
-      exports(children[index], node)
+      assert(children[index], node)
     }
   }
 }
@@ -95,50 +82,53 @@ function unist(node) {
 // same (deep) value.
 function vanilla(key, value) {
   try {
-    assert.deepStrictEqual(value, JSON.parse(JSON.stringify(value)))
-  } catch (_) {
-    assert.fail('non-specced property `' + key + '` should be JSON')
+    nodeAssert.deepStrictEqual(value, JSON.parse(JSON.stringify(value)))
+  } catch {
+    nodeAssert.fail('non-specced property `' + key + '` should be JSON')
   }
 }
 
 // Stringify a value to inspect it.
 // Tries `JSON.stringify()`, and if that fails uses `String()` instead.
 function view(value) {
   try {
-    /* istanbul ignore next - Browser. */
-    return inspect ? inspect(value, {colors: false}) : JSON.stringify(value)
-  } catch (_) {
-    /* istanbul ignore next - Cyclical. */
+    return inspect(value)
+    /* c8 ignore next 3 */
+  } catch {
     return String(value)
   }
 }
 
 // Assert `node` is a parent node.
 function parent(node) {
-  unist(node)
+  assertNode(node)
 
-  assert.strictEqual('value' in node, false, 'parent should not have `value`')
-  assert.ok('children' in node, 'parent should have `children`')
+  nodeAssert.strictEqual(
+    'value' in node,
+    false,
+    'parent should not have `value`'
+  )
+  nodeAssert.ok('children' in node, 'parent should have `children`')
 }
 
 // Assert `node` is a text node.
 function text(node) {
-  unist(node)
+  assertNode(node)
 
-  assert.strictEqual(
+  nodeAssert.strictEqual(
     'children' in node,
     false,
     'text should not have `children`'
   )
-  assert.ok('value' in node, 'text should have `value`')
+  nodeAssert.ok('value' in node, 'text should have `value`')
 }
 
 // Assert `node` is a unist node, but neither parent nor text.
 function empty(node) {
-  unist(node)
+  assertNode(node)
 
-  assert.strictEqual('value' in node, false, 'void should not have `value`')
-  assert.strictEqual(
+  nodeAssert.strictEqual('value' in node, false, 'void should not have `value`')
+  nodeAssert.strictEqual(
     'children' in node,
     false,
     'void should not have `children`'
@@ -147,8 +137,11 @@ function empty(node) {
 
 // Assert `position` is a unist position.
 function position(position) {
-  if (position != null) {
-    assert.ok(object(position), '`position` should be an object')
+  if (position !== null && position !== undefined) {
+    nodeAssert.ok(
+      position === Object(position),
+      '`position` should be an object'
+    )
 
     point(position.start, 'position.start')
     point(position.end, 'position.end')
@@ -157,20 +150,26 @@ function position(position) {
 
 // Assert `point` is a unist point.
 function point(point, name) {
-  if (point != null) {
-    assert.ok(object(point), '`' + name + '` should be an object')
+  if (point !== null && point !== undefined) {
+    nodeAssert.ok(point === Object(point), '`' + name + '` should be an object')
 
-    if (point.line != null) {
-      assert.ok('line' in point, '`' + name + '` should have numeric `line`')
-      assert.ok(point.line >= 1, '`' + name + '.line` should be gte `1`')
+    if (point.line !== null && point.line !== undefined) {
+      nodeAssert.ok(
+        'line' in point,
+        '`' + name + '` should have numeric `line`'
+      )
+      nodeAssert.ok(point.line >= 1, '`' + name + '.line` should be gte `1`')
     }
 
-    if (point.column != null) {
-      assert.ok(
+    if (point.column !== null && point.column !== undefined) {
+      nodeAssert.ok(
         'column' in point,
         '`' + name + '` should have numeric `column`'
       )
-      assert.ok(point.column >= 1, '`' + name + '.column` should be gte `1`')
+      nodeAssert.ok(
+        point.column >= 1,
+        '`' + name + '.column` should be gte `1`'
+      )
     }
   }
 }

inspect.browser.js

@@ -0,0 +1,3 @@
+export function inspect(value) {
+  return JSON.stringify(value)
+}

inspect.js

@@ -0,0 +1,5 @@
+import {inspect as utilInspect} from 'util'
+
+export function inspect(value) {
+  return utilInspect(value, {colors: false})
+}

package.json

@@ -22,35 +22,38 @@
   "contributors": [
     "Titus Wormer <[email protected]> (https://wooorm.com)"
   ],
-  "dependencies": {
-    "x-is-array": "^0.1.0",
-    "x-is-object": "^0.1.0"
+  "sideEffects": false,
+  "type": "module",
+  "main": "index.js",
+  "browser": {
+    "./inspect.js": "./inspect.browser.js"
   },
+  "react-native": {
+    "./inspect.js": "./inspect.browser.js"
+  },
+  "types": "types/index.d.ts",
   "files": [
     "index.js",
+    "inspect.js",
+    "inspect.browser.js",
     "types/index.d.ts"
   ],
-  "types": "types/index.d.ts",
+  "dependencies": {},
   "devDependencies": {
-    "browserify": "^17.0.0",
+    "c8": "^7.0.0",
     "dtslint": "^4.0.0",
-    "nyc": "^15.0.0",
     "prettier": "^2.0.0",
     "remark-cli": "^9.0.0",
     "remark-preset-wooorm": "^8.0.0",
     "tape": "^5.0.0",
-    "tinyify": "^3.0.0",
-    "xo": "^0.35.0"
+    "xo": "^0.38.0"
   },
   "scripts": {
     "format": "remark . -qfo && prettier . -w --loglevel warn && xo --fix",
-    "build-bundle": "browserify . -s unistUtilAssert -o unist-util-assert.js",
-    "build-mangle": "browserify . -s unistUtilAssert -o unist-util-assert.min.js -p tinyify",
-    "build": "npm run build-bundle && npm run build-mangle",
-    "test-api": "node test",
-    "test-coverage": "nyc --reporter lcov tape test",
+    "test-api": "node test/index.js",
+    "test-coverage": "c8 --check-coverage --branches 100 --functions 100 --lines 100 --statements 100 --reporter lcov node test/index.js",
     "test-types": "dtslint types",
-    "test": "npm run format && npm run build && npm run test-coverage && npm run test-types"
+    "test": "npm run format && npm run test-coverage && npm run test-types"
   },
   "prettier": {
     "tabWidth": 2,
@@ -62,24 +65,15 @@
   },
   "xo": {
     "prettier": true,
-    "esnext": false,
     "rules": {
-      "unicorn/prefer-optional-catch-binding": "off",
-      "unicorn/prefer-set-has": "off",
-      "no-eq-null": "off",
-      "eqeqeq": "off"
+      "import/no-mutable-exports": "off",
+      "no-var": "off",
+      "prefer-arrow-callback": "off"
     },
-    "ignores": [
-      "types/",
-      "unist-util-assert.js"
+    "ignore": [
+      "types/"
     ]
   },
-  "nyc": {
-    "check-coverage": true,
-    "lines": 100,
-    "functions": 100,
-    "branches": 100
-  },
   "remarkConfig": {
     "plugins": [
       "preset-wooorm"

readme.md

@@ -12,16 +12,19 @@
 
 ## 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][]:
 
-```bash
+```sh
 npm install unist-util-assert
 ```
 
 ## Use
 
 ```js
-var assert = require('unist-util-assert')
+import {assert} from 'unist-util-assert'
 
 assert({type: 'root', children: []})
 assert({type: 'break'})
@@ -46,6 +49,9 @@ assert({type: 'paragraph', children: ['foo']})
 
 ## API
 
+This package exports the following identifiers: `assert`, `wrap`.
+There is no default export.
+
 ### `assert(tree)`
 
 Assert that [`tree`][tree] is a valid [unist][] [node][].
@@ -70,11 +76,11 @@ Assert that `node` is a valid [unist][] [node][], but neither [parent][] nor
 This module can be used as a base to test subsets of [unist][] (for an example,
 see [`mdast-util-assert`][mdast-util-assert]).
 All functions that are exposed from such a module, and functions used internally
-to test [child][]ren, should be wrapped in `assert.wrap`, which adds an
-inspectable string of the respective node, and its parent when available, to
-the exposed error message.
+to test [child][]ren, should be wrapped in `wrap`, which adds an inspectable
+string of the respective node, and its parent when available, to the exposed
+error message.
 
-### `assert.wrap(fn)`
+### `wrap(fn)`
 
 Wraps `fn` (which is passed a node, and an optional parent node), so that any
 errors thrown inside it will contain information regarding the node (and the

test/children.js

@@ -1,7 +1,5 @@
-'use strict'
-
-var test = require('tape')
-var assert = require('..')
+import test from 'tape'
+import {assert} from '../index.js'
 
 test('children', function (t) {
   t.throws(

test/index.js

@@ -1,13 +1,11 @@
-'use strict'
-
 /* eslint-disable import/no-unassigned-import */
-require('./node')
-require('./type')
-require('./value')
-require('./children')
-require('./position')
-require('./non-defined')
-require('./parent')
-require('./text')
-require('./void')
+import './node.js'
+import './type.js'
+import './value.js'
+import './children.js'
+import './position.js'
+import './non-defined.js'
+import './parent.js'
+import './text.js'
+import './void.js'
 /* eslint-enable import/no-unassigned-import */