import: git: Support 'stable-version-regexp' property.

Some packages (eg: xfce4-panel) use even number for minor version to indicate
a stable release, when refresh such packages to latest versions we'd like them
to be stable ones.  Introduce 'stable-version-regexp' as a package property,
so that unwanted releases can be filtered out.

* doc/guix.texi (Invoking guix refresh): Document 'stable-version-regexp'.
* guix/import/git.scm (import-git-release): Filter out unstable releases when
target-version is unset but 'stable-version-regexp' is available.

Change-Id: I7bbb2cb41b19175a7e3fb79e00cd8dbb20d049ad

2 files changed, 12 insertions, 1 deletions

diff --git a/doc/guix.texi b/doc/guix.texi
index 30c91d0df9d..17d4bdd23a8 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -16124,6 +16124,10 @@ the tag name for separating the numbers of the version.
 pre-releases; to make it also look for pre-releases, set the this
 property to @code{#t}.
 
+@item @code{stable-version-regexp}: a regular expression for matching the
+version string, if specified the updater will pick the latest version from
+matching ones when the @option{--target-version} option is omitted.
+
 @end itemize
 
 @lisp
diff --git a/guix/import/git.scm b/guix/import/git.scm
index 8d443895cf1..81ea9b73988 100644
--- a/guix/import/git.scm
+++ b/guix/import/git.scm
@@ -206,7 +206,14 @@ a version prefix when PARTIAL-VERSION? is #t."
          (old-reference (origin-uri (package-source package)))
          (tags (get-package-tags package))
          (versions (map car tags))
-         (version (find-version versions version partial-version?))
+         (stable-rx (and=> (assq-ref (package-properties package)
+                                     'stable-version-regexp)
+                           make-regexp))
+         (version (find-version
+                   (if (and stable-rx (not version))
+                       (filter (cut regexp-exec stable-rx <>) versions)
+                       versions)
+                   version partial-version?))
          (tag (assoc-ref tags version)))
     (and version
          (upstream-source