Fix for loading markdown pages with spaces in the name

.changeset/stupid-donkeys-care.md

@@ -0,0 +1,5 @@
+---
+'astro': patch
+---
+
+Fixes issue with loading md pages in project with a space in folder name

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

@@ -9,8 +9,8 @@ import type { Plugin } from 'vite';
 import type { AstroConfig } from '../@types/astro';
 import { PAGE_SSR_SCRIPT_ID } from '../vite-plugin-scripts/index.js';
 import { pagesVirtualModuleId } from '../core/app/index.js';
-import { appendForwardSlash } from '../core/path.js';
-import { resolvePages } from '../core/util.js';
+import { appendForwardSlash, prependForwardSlash } from '../core/path.js';
+import { resolvePages, viteID } from '../core/util.js';
 
 interface AstroPluginOptions {
 	config: AstroConfig;
@@ -156,7 +156,9 @@ ${setup}`.trim();
 					site: config.site ? new URL(config.base, config.site).toString() : undefined,
 					sourcefile: id,
 					sourcemap: 'inline',
-					internalURL: `/@fs${new URL('../runtime/server/index.js', import.meta.url).pathname}`,
+					internalURL: `/@fs${prependForwardSlash(
+						viteID(new URL('../runtime/server/index.js', import.meta.url))
+					)}`,
 				});
 
 				tsResult = `\nexport const metadata = ${JSON.stringify(metadata)};

packages/astro/test/astro-pages.test.js

@@ -1,19 +1,46 @@
 import { expect } from 'chai';
 import * as cheerio from 'cheerio';
-import { loadFixture } from './test-utils.js';
+import { loadFixture, isWindows} from './test-utils.js';
 
 describe('Pages', () => {
 	let fixture;
 
 	before(async () => {
-		fixture = await loadFixture({ root: './fixtures/astro-pages/' });
+		fixture = await loadFixture({ root: './fixtures/astro pages/' });
 		await fixture.build();
 	});
 
-	it('Can find page with "index" at the end file name', async () => {
-		const html = await fixture.readFile('/posts/name-with-index/index.html');
-		const $ = cheerio.load(html);
+	describe('Build', () => {
+		before(async () => {
+			await fixture.build();
+		});
 
-		expect($('h1').text()).to.equal('Name with index');
+		it('Can find page with "index" at the end file name', async () => {
+			const html = await fixture.readFile('/posts/name-with-index/index.html');
+			const $ = cheerio.load(html);
+
+			expect($('h1').text()).to.equal('Name with index');
+		});
+	});
+
+	if(isWindows) return;
+
+	describe('Development', () => {
+		let devServer;
+
+		before(async () => {
+			devServer = await fixture.startDevServer();
+		});
+
+		after(async () => {
+			await devServer.stop();
+		});
+
+		it('Is able to load md pages', async () => {
+			const html = await fixture.fetch('/').then((res) => res.text());
+			const $ = cheerio.load(html);
+
+			expect($('#testing').length).to.be.greaterThan(0);
+		});
 	});
 });

packages/astro/test/fixtures/astro pages/src/pages/index.md

@@ -0,0 +1 @@
+# Testing