Catch ValueError to prevent stack trace
diff --git a/buildstream/plugins/sources/_downloadablefilesource.py b/buildstream/plugins/sources/_downloadablefilesource.py
index ec9c0fb..4df4034 100644
--- a/buildstream/plugins/sources/_downloadablefilesource.py
+++ b/buildstream/plugins/sources/_downloadablefilesource.py
@@ -155,6 +155,9 @@
except (urllib.error.URLError, urllib.error.ContentTooShortError, OSError) as e:
raise SourceError("{}: Error mirroring {}: {}"
.format(self, self.url, e)) from e
+ except ValueError as e:
+ raise SourceError("{}: Error mirroring {}: {}"
+ .format(self, self.url, e)) from e
def _get_mirror_dir(self):
return os.path.join(self.get_mirror_directory(),