Merge ~pieq/oem-qa-autosummary:fix-lp1935771-new-bugs-mutable-default-args into oem-qa-autosummary:master

[Pierre Equoy]

This fixes lp:1935771.

See commit message for more information.

To test:

Use a project with a recent milestone, and make sure that the expected new bugs are retrieved.

Check in the logs for the phrase "Search bugs from {created_since} to {created_before} for {self.project_name} project", where created_before should change every time you request a new summary.

[Kristin Chuang (kristinchuang)]

works for me, +1

Tried out the changes in a local deployment around 2021-07-13 16:55:

[OK] correct `created_before` date detected:
https://pastebin.canonical.com/p/CdCQpZbkwv/ row #11

[OK] a correct set of new bugs returned

review: Approve

diff --git a/autosummary/summary.py b/autosummary/summary.py
index c38c071..9a08276 100644
--- a/autosummary/summary.py
+++ b/autosummary/summary.py
@@ -67,7 +67,7 @@ class Summary:
                     return user, passwd
         return "", ""
 
-    def get_new_bugs(self, created_since=None, created_before=datetime.today()):
+    def get_new_bugs(self, created_since=None, created_before=None):
         """
         Return a list of bugs that have been opened by a Canonical QA engineer
         in the same project between `created_since` and `created_before`. Bugs
@@ -78,6 +78,10 @@ class Summary:
 
         if created_since is None:
             created_since = self.image_date
+
+        if created_before is None:
+            created_before = datetime.today()
+
         new_bugs = []
         logging.info((f"Search bugs from {created_since} to {created_before}"
                       f" for {self.project_name} project"))