Fix build failure when image file name includes special characters (#9781)

The latest version of `vite-plugin-markdown` uses a regular
expression that includes the file path via string concatenation.
However the file path is not escaped for use in a regular
expressions. So if a markdown document includes a reference to an
image file name which includes certain special characters it will
cause the build to fail.

This patch escapes regex special characters in the file path string
being injected into the regular expression. While I found that not
all special characters will cause this problem, it seems safer to
simply escape all regex specials. I also added test to verify this.

Related to: Commit 165cfc154b

Co-authored-by: Erika <3019731+Princesseuh@users.noreply.github.com>

.changeset/weak-plums-sip.md

@@ -0,0 +1,5 @@
+---
+"astro": patch
+---
+
+Fix build failure when image file name includes special characters

packages/astro/src/vite-plugin-markdown/images.ts

@@ -13,7 +13,7 @@ export function getMarkdownCodeForImages(imagePaths: MarkdownImagePath[], html:
 						.map((entry) => {
 							const rawUrl = JSON.stringify(entry.raw);
 							return `{
-											const regex = new RegExp('__ASTRO_IMAGE_="([^"]*' + ${rawUrl} + '[^"]*)"', 'g');
+											const regex = new RegExp('__ASTRO_IMAGE_="([^"]*' + ${rawUrl.replace(/[.*+?^${}()|[\]\\]/g, '\\\\$&')} + '[^"]*)"', 'g');
 											let match;
 											let occurrenceCounter = 0;
 											while ((match = regex.exec(html)) !== null) {

packages/astro/test/core-image.test.js

@@ -427,6 +427,15 @@ describe('astro:image', () => {
 				expect($img.attr('src').startsWith('/_image')).to.equal(true);
 			});
 
+			it('Supports special characters in file name', async () => {
+				let res = await fixture.fetch('/specialChars');
+				let html = await res.text();
+				$ = cheerio.load(html);
+
+				let $img = $('img');
+				expect($img.attr('src').startsWith('/_image')).to.equal(true);
+			});
+
 			it('properly handles remote images', async () => {
 				let res = await fixture.fetch('/httpImage');
 				let html = await res.text();

packages/astro/test/fixtures/core-image/src/pages/specialChars.md

@@ -0,0 +1,3 @@
+![C++](../assets/c++.png)
+
+Image with special characters in file name worked.