Ensure file and url are always present in MDX for Astro.glob (#4076)

1 files changed, 22 insertions, 4 deletions

diff --git a/packages/integrations/mdx/src/utils.ts b/packages/integrations/mdx/src/utils.ts
index 1091e8511..c824c39c3 100644
--- a/packages/integrations/mdx/src/utils.ts
+++ b/packages/integrations/mdx/src/utils.ts
@@ -4,16 +4,34 @@ function appendForwardSlash(path: string) {
 	return path.endsWith('/') ? path : path + '/';
 }
 
+interface FileInfo {
+	fileId: string;
+	fileUrl: string;
+}
+
 /** @see 'vite-plugin-utils' for source */
-export function getFileInfo(id: string, config: AstroConfig) {
+export function getFileInfo(id: string, config: AstroConfig): FileInfo {
 	const sitePathname = appendForwardSlash(
 		config.site ? new URL(config.base, config.site).pathname : config.base
 	);
 
+	// Try to grab the file's actual URL
+	let url: URL | undefined = undefined;
+	try {
+		url = new URL(`file://${id}`);
+	} catch {}
+
 	const fileId = id.split('?')[0];
-	let fileUrl = fileId.includes('/pages/')
-		? fileId.replace(/^.*?\/pages\//, sitePathname).replace(/(\/index)?\.mdx$/, '')
-		: undefined;
+	let fileUrl: string;
+	const isPage = fileId.includes('/pages/');
+	if(isPage) {
+		fileUrl = fileId.replace(/^.*?\/pages\//, sitePathname).replace(/(\/index)?\.mdx$/, '');
+	} else if(url && url.pathname.startsWith(config.root.pathname)) {
+		fileUrl = url.pathname.slice(config.root.pathname.length);
+	} else {
+		fileUrl = fileId;
+	}
+
 	if (fileUrl && config.trailingSlash === 'always') {
 		fileUrl = appendForwardSlash(fileUrl);
 	}