guix build: Gracefully handle invalid '--with-git-url' specs.

* guix/scripts/build.scm (transform-package-source-git-url): Add case
for when 'string-split' does not return exactly two elements.

diff --git a/guix/scripts/build.scm b/guix/scripts/build.scm
index 8d5411e..8fa700c 100644 (file)
--- a/guix/scripts/build.scm
+++ b/guix/scripts/build.scm
@@ -370,7 +370,10 @@ a checkout of the Git repository at the given URL."
                       (package
                         (inherit old)
                         (source (git-checkout (url url)
-                                              (recursive? #t)))))))))
+                                              (recursive? #t)))))))
+             (_
+              (leave (G_ "~a: invalid Git URL replacement specification~%")
+                     spec))))
          replacement-specs))
 
   (define rewrite