Fix URL calculation in clone input box (#29470)

Ported the function as-is and added comments so we don't forget about
this in the future.

Fixes: https://github.com/go-gitea/gitea/issues/29462

1 files changed, 15 insertions, 7 deletions

diff --git a/templates/repo/clone_script.tmpl b/templates/repo/clone_script.tmpl
index 0376da4a71..40dae76dc7 100644
--- a/templates/repo/clone_script.tmpl
+++ b/templates/repo/clone_script.tmpl
@@ -24,14 +24,22 @@
 		const btn = isSSH ? sshBtn : httpsBtn;
 		if (!btn) return;
 
-		let link = btn.getAttribute('data-link');
-		if (link.startsWith('http://') || link.startsWith('https://')) {
-			// use current protocol/host as the clone link
-			const url = new URL(link);
-			url.protocol = window.location.protocol;
-			url.host = window.location.host;
-			link = url.toString();
+		// NOTE: Keep this function in sync with the one in the js folder
+		function toOriginUrl(urlStr) {
+			try {
+				if (urlStr.startsWith('http://') || urlStr.startsWith('https://') || urlStr.startsWith('/')) {
+					const {origin, protocol, hostname, port} = window.location;
+					const url = new URL(urlStr, origin);
+					url.protocol = protocol;
+					url.hostname = hostname;
+					url.port = port || (protocol === 'https:' ? '443' : '80');
+					return url.toString();
+				}
+			} catch {}
+			return urlStr;
 		}
+		const link = toOriginUrl(btn.getAttribute('data-link'));
+
 		for (const el of document.getElementsByClassName('js-clone-url')) {
 			el[el.nodeName === 'INPUT' ? 'value' : 'textContent'] = link;
 		}