From 089a5e7b7b41b83d3196ec096ea2fe5d3f1d1019 Mon Sep 17 00:00:00 2001
From: Remco Haszing <remcohaszing@gmail.com>
Date: Fri, 18 Apr 2025 19:51:16 +0200
Subject: [PATCH 1/2] Memoize the processor in MarkdownHooks
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Some plugins may perform heavy work in preparation to make the
transformer light-weight. A good example of this is
`rehype-starry-night`.

Without this change, an interactive markdown editor which includes
`rehype-starry-night` is very sluggish. With this change, performance is
as good as if `rehype-starry-night` isn’t even used.
---
 lib/index.js | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/lib/index.js b/lib/index.js
index 6e3fdd2..7600018 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -107,7 +107,7 @@ import {unreachable} from 'devlop'
 import {toJsxRuntime} from 'hast-util-to-jsx-runtime'
 import {urlAttributes} from 'html-url-attributes'
 import {Fragment, jsx, jsxs} from 'react/jsx-runtime'
-import {useEffect, useState} from 'react'
+import {useEffect, useMemo, useState} from 'react'
 import remarkParse from 'remark-parse'
 import remarkRehype from 'remark-rehype'
 import {unified} from 'unified'
@@ -212,7 +212,10 @@ export async function MarkdownAsync(options) {
  *   React node.
  */
 export function MarkdownHooks(options) {
-  const processor = createProcessor(options)
+  const processor = useMemo(
+    () => createProcessor(options),
+    [options.rehypePlugins, options.remarkPlugins, options.remarkRehypeOptions]
+  )
   const [error, setError] = useState(
     /** @type {Error | undefined} */ (undefined)
   )
@@ -238,12 +241,7 @@ export function MarkdownHooks(options) {
         cancelled = true
       }
     },
-    [
-      options.children,
-      options.rehypePlugins,
-      options.remarkPlugins,
-      options.remarkRehypeOptions
-    ]
+    [options.children, processor]
   )
 
   if (error) throw error

From 087408fd819fda187eff42e5257993f69811a5bb Mon Sep 17 00:00:00 2001
From: Remco Haszing <remcohaszing@gmail.com>
Date: Sat, 19 Apr 2025 17:33:53 +0200
Subject: [PATCH 2/2] Replace arrow function with a function expression

---
 lib/index.js | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/index.js b/lib/index.js
index 7600018..06f07e1 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -213,7 +213,9 @@ export async function MarkdownAsync(options) {
  */
 export function MarkdownHooks(options) {
   const processor = useMemo(
-    () => createProcessor(options),
+    function () {
+      return createProcessor(options)
+    },
     [options.rehypePlugins, options.remarkPlugins, options.remarkRehypeOptions]
   )
   const [error, setError] = useState(