Use ESM

Author: wooorm

.gitignore

@@ -1,6 +1,5 @@
 .DS_Store
 *.log
-.nyc_output/
 coverage/
 node_modules/
 yarn.lock

.prettierignore

@@ -1,3 +1,2 @@
 coverage/
-*.json
 *.md

index.js

@@ -1,15 +1,13 @@
-'use strict'
+import sax from 'sax'
+import Message from 'vfile-message'
 
-var Parser = require('sax').SAXParser
-var Message = require('vfile-message')
-
-module.exports = fromXml
+var Parser = sax.SAXParser
 
 var fromCharCode = String.fromCharCode
 
 var search = /\r?\n|\r/g
 
-function fromXml(doc) {
+export function fromXml(doc) {
   var parser = new Parser(true, {position: true, strictEntities: true})
   var stack = [{type: 'root', children: []}]
   var position = now()
@@ -32,16 +30,17 @@ function fromXml(doc) {
 
   function onerror(error) {
     var index = error.message.indexOf('\nLine')
-    /* istanbul ignore next
-     * - The substring should always be included, but this guards against
-     * changes in newer sax versions */
+    // The substring should always be included, but this guards against
+    // changes in newer sax versions.
+    /* c8 ignore next */
     fail(index === -1 ? error.message : error.message.slice(0, index), 'sax')
   }
 
   function onsgmldeclaration() {
     fail('Unexpected SGML declaration', 'unexpected-sgml')
   }
 
+  // eslint-disable-next-line complexity
   function ondoctype(value) {
     var node = {type: 'doctype', name: '', public: null, system: null}
     var index = -1
@@ -97,24 +96,39 @@ function fromXml(doc) {
             // Done.
           } else if (isSpace(code)) {
             // As expected.
-          } else if (code === 80 /* `P` */) {
-            state = 'IN_EID'
-            returnState = 'AFTER_PUBLIC'
-            buffer = 'PUBLIC'
-            bufferIndex = 0
-          } else if (code === 83 /* `S` */) {
-            state = 'IN_EID'
-            returnState = 'AFTER_SYSTEM'
-            buffer = 'SYSTEM'
-            bufferIndex = 0
-          } else if (code === 91 /* `[` */) {
-            fail('Unexpected internal subset', 'doctype-internal-subset')
-          } else {
-            fail(
-              'Expected external identifier (`PUBLIC` or `SYSTEM`), whitespace, or doctype end',
-              'doctype-external-identifier'
-            )
-          }
+          } else
+            switch (code) {
+              case 80: {
+                state = 'IN_EID'
+                returnState = 'AFTER_PUBLIC'
+                buffer = 'PUBLIC'
+                bufferIndex = 0
+
+                break
+              }
+
+              case 83: {
+                state = 'IN_EID'
+                returnState = 'AFTER_SYSTEM'
+                buffer = 'SYSTEM'
+                bufferIndex = 0
+
+                break
+              }
+
+              case 91: {
+                fail('Unexpected internal subset', 'doctype-internal-subset')
+
+                break
+              }
+
+              default: {
+                fail(
+                  'Expected external identifier (`PUBLIC` or `SYSTEM`), whitespace, or doctype end',
+                  'doctype-external-identifier'
+                )
+              }
+            }
 
           break
         case 'IN_EID':
@@ -203,9 +217,9 @@ function fromXml(doc) {
 
           break
         case 'IN_SYSTEM_LITERAL':
-          /* istanbul ignore next
-           * - Handled by SAX, but keep it to guard against changes in newer sax
-           * versions. */
+          // Handled by SAX, but keep it to guard against changes in newer sax
+          // versions.
+          /* c8 ignore next 5 */
           if (code === null /* EOF */) {
             fail(
               'Expected quote or apostrophe to end system literal',
@@ -232,7 +246,8 @@ function fromXml(doc) {
           }
 
           break
-        /* istanbul ignore next - Guard against new states */
+        // Guard against new states.
+        /* c8 ignore next 2 */
         default:
           throw new Error('Unhandled state `' + state + '`')
       }
@@ -252,7 +267,7 @@ function fromXml(doc) {
   }
 
   function oncomment(value) {
-    var node = {type: 'comment', value: value}
+    var node = {type: 'comment', value}
 
     // Comment has a positional bug… 😢
     // They end right before the last character (`>`), so let’s add that:
@@ -276,7 +291,7 @@ function fromXml(doc) {
   }
 
   function ontext(value) {
-    var node = {type: 'text', value: value}
+    var node = {type: 'text', value}
     // Text has a positional bug… 😢
     // When they are added, the position is already at the next token.
     // So let’s reverse that.
@@ -343,7 +358,7 @@ function fromXml(doc) {
 
 // See: <https://www.w3.org/TR/xml/#NT-NameStartChar>
 function isNameStartChar(code) {
-  return /[:A-Z_a-z\xc0-\xd6\xd8-\xf6\xf8-\u02ff\u0370-\u037d\u037f-\u1fff\u200c\u200d\u2070-\u218f\u2c00-\u2fef\u3001-\ud7ff\uf900-\ufdcf\ufdf0-\ufffd]/.test(
+  return /[:A-Z_a-z\u00C0-\u00D6\u00D8-\u00F6\u00F8-\u02FF\u0370-\u037D\u037F-\u1FFF\u200C\u200D\u2070-\u218F\u2C00-\u2FEF\u3001-\uD7FF\uF900-\uFDCF\uFDF0-\uFFFD]/.test(
     fromCharCode(code)
   )
 }
@@ -352,7 +367,7 @@ function isNameStartChar(code) {
 function isNameChar(code) {
   return (
     isNameStartChar(code) ||
-    /[-.\d\xb7\u0300-\u036f\u203f\u2040]/.test(fromCharCode(code))
+    /[-.\d\u00B7\u0300-\u036F\u203F\u2040]/.test(fromCharCode(code))
   )
 }
 

package.json

@@ -28,6 +28,9 @@
   "contributors": [
     "Titus Wormer <[email protected]> (https://wooorm.com)"
   ],
+  "sideEffects": false,
+  "type": "module",
+  "main": "index.js",
   "files": [
     "index.js"
   ],
@@ -36,27 +39,20 @@
     "vfile-message": "^2.0.0"
   },
   "devDependencies": {
-    "is-hidden": "^1.0.0",
-    "negate": "^1.0.0",
-    "nyc": "^15.0.0",
+    "c8": "^7.0.0",
+    "is-hidden": "^2.0.0",
     "prettier": "^2.0.0",
     "remark-cli": "^9.0.0",
     "remark-preset-wooorm": "^8.0.0",
     "tape": "^5.0.0",
-    "xo": "^0.38.0"
+    "xo": "^0.39.0"
   },
   "scripts": {
     "format": "remark . -qfo && prettier . -w --loglevel warn && xo --fix",
-    "test-api": "node test",
-    "test-coverage": "nyc --reporter lcov tape test/index.js",
+    "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": "npm run format && npm run test-coverage"
   },
-  "nyc": {
-    "check-coverage": true,
-    "lines": 100,
-    "functions": 100,
-    "branches": 100
-  },
   "prettier": {
     "tabWidth": 2,
     "useTabs": false,
@@ -67,14 +63,10 @@
   },
   "xo": {
     "prettier": true,
-    "esnext": false,
     "rules": {
-      "complexity": "off",
       "no-misleading-character-class": "off",
-      "unicorn/escape-case": "off",
-      "unicorn/no-hex-escape": "off",
-      "unicorn/no-fn-reference-in-iterator": "off",
-      "unicorn/prefer-optional-catch-binding": "off"
+      "no-var": "off",
+      "prefer-arrow-callback": "off"
     }
   },
   "remarkConfig": {

readme.md

@@ -12,6 +12,9 @@
 
 ## 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
@@ -33,8 +36,8 @@ Say we have the following XML file, `example.xml`:
 And our script, `example.js`, looks as follows:
 
 ```js
-var fs = require('fs')
-var fromXml = require('xast-util-from-xml')
+import fs from 'fs'
+import {fromXml} from 'xast-util-from-xml'
 
 var doc = fs.readFileSync('example.xml')
 
@@ -85,6 +88,9 @@ Now, running `node example` yields (positional info removed for brevity):
 
 ## API
 
+This package exports the following identifiers: `fromXml`.
+There is no default export.
+
 ### `fromXml(doc)`
 
 Parse XML to a **[xast][]** tree.

test/index.js

@@ -1,11 +1,8 @@
-'use strict'
-
-var fs = require('fs')
-var path = require('path')
-var test = require('tape')
-var negate = require('negate')
-var hidden = require('is-hidden')
-var fromXml = require('..')
+import fs from 'fs'
+import path from 'path'
+import test from 'tape'
+import {isHidden} from 'is-hidden'
+import {fromXml} from '../index.js'
 
 var join = path.join
 
@@ -208,11 +205,13 @@ test('xast-util-from-xml', function (t) {
 
 test('fixtures', function (t) {
   var base = join('test', 'fixtures')
-  var files = fs.readdirSync(base).filter(negate(hidden))
+  var files = fs.readdirSync(base)
   var index = -1
 
   while (++index < files.length) {
-    each(files[index])
+    if (!isHidden(files[index])) {
+      each(files[index])
+    }
   }
 
   t.end()
@@ -225,7 +224,7 @@ test('fixtures', function (t) {
 
     try {
       expected = JSON.parse(fs.readFileSync(fp))
-    } catch (_) {
+    } catch {
       // New fixture.
       fs.writeFileSync(fp, JSON.stringify(actual, 0, 2) + '\n')
       return