From ae487615a635cc5cde0dc500a3c44b25a1dfdb40 Mon Sep 17 00:00:00 2001
From: zimbatm <zimbatm@zimbatm.com>
Date: Fri, 18 Mar 2016 19:47:19 +0000
Subject: [PATCH] nix-prefetch-git: fix url_to_name heuristic

The function wasn't checking that *all* of the characters where
[a-z0-9]. Fixes #13921
---
 pkgs/build-support/fetchgit/nix-prefetch-git | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pkgs/build-support/fetchgit/nix-prefetch-git b/pkgs/build-support/fetchgit/nix-prefetch-git
index 2c9d61504ed2..97c983dbe8da 100755
--- a/pkgs/build-support/fetchgit/nix-prefetch-git
+++ b/pkgs/build-support/fetchgit/nix-prefetch-git
@@ -118,7 +118,7 @@ url_to_name(){
     # basename removes the / and .git suffixes
     local base=$(basename "$url" .git)
 
-    if [[ $ref =~ [a-z0-9]+ ]]; then
+    if [[ $ref =~ ^[a-z0-9]+$ ]]; then
         echo "$base-${ref:0:7}"
     else
         echo $base