[PATCH 2/3] tests/functional: fix formatting of exception args

["Daniel P. Berrangé" <berrange@redhat.com>]

On HTTP 404 errors, we failed to include the URL in the exception
that was raised, while for the catch-all exception we failed to
include the URL and forgot the placeholder for the exception
details too.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
 tests/functional/qemu_test/asset.py | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/tests/functional/qemu_test/asset.py b/tests/functional/qemu_test/asset.py
index b5a6136d36..ae2bec3ea5 100644
--- a/tests/functional/qemu_test/asset.py
+++ b/tests/functional/qemu_test/asset.py
@@ -168,12 +168,13 @@ def fetch(self):
                 # indicate a broken test rather than a transient
                 # server or networking problem
                 if e.code == 404:
-                    raise AssetError(self, "Unable to download: "
-                                     "HTTP error %d" % e.code)
+                    raise AssetError(self, "Unable to download %s: "
+                                     "HTTP error %d" % (self.url, e.code))
                 continue
             except Exception as e:
                 tmp_cache_file.unlink()
-                raise AssetError(self, "Unable to download: " % e)
+                raise AssetError(self, "Unable to download %s: %s" % (
+                    self.url, e))
 
         if not os.path.exists(tmp_cache_file):
             raise AssetError(self, "Download retries exceeded", transient=True)
-- 
2.50.1