Refactor code-style

Author: wooorm

lib/index.js

@@ -5,33 +5,49 @@
 
 import {toc} from 'mdast-util-toc'
 
+/** @type {Readonly<Options>} */
+const emptyOptions = {}
+
 /**
- * Plugin to generate a Table of Contents (TOC).
+ * Generate a table of contents (TOC).
  *
- * @type {import('unified').Plugin<[Options?]|void[], Root>}
+ * @param {Readonly<Options> | null | undefined} [options]
+ *   Configuration (optional).
+ * @returns
+ *   Transform.
  */
-export default function remarkToc(options = {}) {
-  return (node) => {
-    const result = toc(
-      node,
-      Object.assign({}, options, {
-        heading: options.heading || 'toc|table[ -]of[ -]contents?'
-      })
-    )
+export default function remarkToc(options) {
+  let settings = options || emptyOptions
+
+  if (!settings.heading) {
+    settings = {...settings, heading: 'toc|table[ -]of[ -]contents?'}
+  }
+
+  /**
+   * Transform.
+   *
+   * @param {Root} tree
+   *   Tree.
+   * @returns {undefined}
+   *   Nothing.
+   */
+  return function (tree) {
+    const result = toc(tree, settings)
 
     if (
-      result.endIndex === null ||
-      result.index === null ||
+      result.endIndex === undefined ||
+      result.endIndex === -1 ||
+      result.index === undefined ||
       result.index === -1 ||
       !result.map
     ) {
       return
     }
 
-    node.children = [
-      ...node.children.slice(0, result.index),
+    tree.children = [
+      ...tree.children.slice(0, result.index),
       result.map,
-      ...node.children.slice(result.endIndex)
+      ...tree.children.slice(result.endIndex)
     ]
   }
 }

package.json

@@ -40,8 +40,7 @@
   ],
   "dependencies": {
     "@types/mdast": "^4.0.0",
-    "mdast-util-toc": "^7.0.0",
-    "unified": "^11.0.0"
+    "mdast-util-toc": "^7.0.0"
   },
   "devDependencies": {
     "@types/node": "^20.0.0",

readme.md

@@ -238,7 +238,7 @@ so:
  async function main() {
    const file = await remark()
 -    .use(remarkToc)
-+    .use(remarkToc, {tight: true, ordered: true})
++    .use(remarkToc, {ordered: true, tight: true})
      .process(await read('example.md'))
 
    console.log(String(file))
@@ -265,7 +265,7 @@ so:
  async function main() {
    const file = await remark()
 -    .use(remarkToc)
-+    .use(remarkToc, {maxDepth: 3, skip: 'delta', parents: ['root', 'listItem']})
++    .use(remarkToc, {maxDepth: 3, parents: ['listItem', 'root'], skip: 'delta'})
      .process(await read('example.md'))
 
    console.log(String(file))

test/index.js

@@ -6,11 +6,19 @@ import assert from 'node:assert/strict'
 import fs from 'node:fs/promises'
 import process from 'node:process'
 import test from 'node:test'
-import {remark} from 'remark'
 import {isHidden} from 'is-hidden'
+import {remark} from 'remark'
 import remarkToc from '../index.js'
 
 test('remarkToc', async function (t) {
+  await t.test('should expose the public api', async function () {
+    assert.deepEqual(Object.keys(await import('../index.js')).sort(), [
+      'default'
+    ])
+  })
+})
+
+test('fixtures', async function (t) {
   const base = new URL('fixtures/', import.meta.url)
   const folders = await fs.readdir(base)
 
@@ -38,9 +46,7 @@ test('remarkToc', async function (t) {
         config = JSON.parse(String(await fs.readFile(configUrl)))
       } catch {}
 
-      const proc = remark()
-        // @ts-expect-error: to do: fix type.
-        .use(remarkToc, config)
+      const proc = remark().use(remarkToc, config)
 
       const actual = String(await proc.process(input))