+ self._single_revision = None
+
+ def send_single_combined_email(self, known_added_sha1s):
+ if not self.environment.combine_when_single_commit:
+ return None
+
+ # In the sadly-all-too-frequent usecase of people pushing only
+ # one of their commits at a time to a repository, users feel
+ # the reference change summary emails are noise rather than
+ # important signal. This is because, in this particular
+ # usecase, there is a reference change summary email for each
+ # new commit, and all these summaries do is point out that
+ # there is one new commit (which can readily be inferred by
+ # the existence of the individual revision email that is also
+ # sent). In such cases, our users prefer there to be a combined
+ # reference change summary/new revision email.
+ #
+ # So, if the change is an update and it doesn't discard any
+ # commits, and it adds exactly one non-merge commit (gerrit
+ # forces a workflow where every commit is individually merged
+ # and the git-multimail hook fired off for just this one
+ # change), then we send a combined refchange/revision email.
+ try:
+ # If this change is a reference update that doesn't discard
+ # any commits...
+ if self.change_type != 'update':
+ return None
+
+ if read_git_lines(
+ ['merge-base', self.old.sha1, self.new.sha1]
+ ) != [self.old.sha1]:
+ return None
+
+ # Check if this update introduced exactly one non-merge
+ # commit:
+
+ def split_line(line):
+ """Split line into (sha1, [parent,...])."""
+
+ words = line.split()
+ return (words[0], words[1:])
+
+ # Get the new commits introduced by the push as a list of
+ # (sha1, [parent,...])
+ new_commits = [
+ split_line(line)
+ for line in read_git_lines(
+ [
+ 'log', '-3', '--format=%H %P',
+ '%s..%s' % (self.old.sha1, self.new.sha1),
+ ]
+ )
+ ]
+
+ if not new_commits:
+ return None
+
+ # If the newest commit is a merge, save it for a later check
+ # but otherwise ignore it
+ merge = None
+ tot = len(new_commits)
+ if len(new_commits[0][1]) > 1:
+ merge = new_commits[0][0]
+ del new_commits[0]
+
+ # Our primary check: we can't combine if more than one commit
+ # is introduced. We also currently only combine if the new
+ # commit is a non-merge commit, though it may make sense to
+ # combine if it is a merge as well.
+ if not (
+ len(new_commits) == 1
+ and len(new_commits[0][1]) == 1
+ and new_commits[0][0] in known_added_sha1s
+ ):
+ return None
+
+ # We do not want to combine revision and refchange emails if
+ # those go to separate locations.
+ rev = Revision(self, GitObject(new_commits[0][0]), 1, tot)
+ if rev.recipients != self.recipients:
+ return None
+
+ # We ignored the newest commit if it was just a merge of the one
+ # commit being introduced. But we don't want to ignore that
+ # merge commit it it involved conflict resolutions. Check that.
+ if merge and merge != read_git_output(['diff-tree', '--cc', merge]):
+ return None
+
+ # We can combine the refchange and one new revision emails
+ # into one. Return the Revision that a combined email should
+ # be sent about.
+ return rev
+ except CommandError:
+ # Cannot determine number of commits in old..new or new..old;
+ # don't combine reference/revision emails:
+ return None
+
+ def generate_combined_email(self, push, revision, body_filter=None, extra_header_values={}):
+ values = revision.get_values()
+ if extra_header_values:
+ values.update(extra_header_values)
+ if 'subject' not in extra_header_values:
+ values['subject'] = self.expand(COMBINED_REFCHANGE_REVISION_SUBJECT_TEMPLATE, **values)
+
+ self._single_revision = revision
+ self.header_template = COMBINED_HEADER_TEMPLATE
+ self.intro_template = COMBINED_INTRO_TEMPLATE
+ self.footer_template = COMBINED_FOOTER_TEMPLATE
+ for line in self.generate_email(push, body_filter, values):
+ yield line
+
+ def generate_email_body(self, push):
+ '''Call the appropriate body generation routine.
+
+ If this is a combined refchange/revision email, the special logic
+ for handling this combined email comes from this function. For
+ other cases, we just use the normal handling.'''
+
+ # If self._single_revision isn't set; don't override
+ if not self._single_revision:
+ for line in super(BranchChange, self).generate_email_body(push):
+ yield line
+ return
+
+ # This is a combined refchange/revision email; we first provide
+ # some info from the refchange portion, and then call the revision
+ # generate_email_body function to handle the revision portion.
+ adds = list(generate_summaries(
+ '--topo-order', '--reverse', '%s..%s'
+ % (self.old.commit_sha1, self.new.commit_sha1,)
+ ))
+
+ yield self.expand("The following commit(s) were added to %(refname)s by this push:\n")
+ for (sha1, subject) in adds:
+ yield self.expand(
+ BRIEF_SUMMARY_TEMPLATE, action='new',
+ rev_short=sha1, text=subject,
+ )
+
+ yield self._single_revision.rev.short + " is described below\n"
+ yield '\n'
+
+ for line in self._single_revision.generate_email_body(push):
+ yield line