[jhbuild] [tarball] skip unset directories when looking for patches (GNOME bug 583420)

[Frederic Peters <fpeters src gnome org>]

commit 59e29e08e75435796e24176854646cf6d63607ec
Author: Frédéric Péters <fpeters 0d be>
Date:   Thu May 21 11:06:54 2009 +0200

    [tarball] skip unset directories when looking for patches (GNOME bug 583420)
---
 jhbuild/versioncontrol/tarball.py |   14 +++++++++-----
 1 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/jhbuild/versioncontrol/tarball.py b/jhbuild/versioncontrol/tarball.py
index 2b44a58..4fb5608 100644
--- a/jhbuild/versioncontrol/tarball.py
+++ b/jhbuild/versioncontrol/tarball.py
@@ -241,11 +241,15 @@ class TarballBranch(Branch):
 
             if not patchfile:
                 # nothing else, use jhbuild provided patches
-                for dirname in (
-                        os.path.join(self.config.modulesets_dir, 'patches'),
-                        os.path.join(self.config.modulesets_dir, '../patches'),
-                        os.path.join(PKGDATADIR, 'patches', patch),
-                        os.path.join(SRCDIR, 'patches', patch)):
+                possible_locations = []
+                if self.config.modulesets_dir:
+                    possible_locations.append(os.path.join(self.config.modulesets_dir, 'patches'))
+                    possible_locations.append(os.path.join(self.config.modulesets_dir, '../patches'))
+                if PKGDATADIR:
+                    possible_locations.append(os.path.join(PKGDATADIR, 'patches'))
+                if SRCDIR:
+                    possible_locations.append(os.path.join(SRCDIR, 'patches'))
+                for dirname in possible_locations:
                     patchfile = os.path.join(dirname, patch)
                     if os.path.exists(patchfile):
                         break