localrepo: have stream_in() not modify its argument
Localrepo's stream_in function modified its requirements argument. This is not
good practice because it may be unexpected behavior to the caller.
--- a/mercurial/localrepo.py Wed Apr 22 12:06:44 2015 -0700
+++ b/mercurial/localrepo.py Wed Apr 22 12:59:12 2015 -0700
@@ -1827,8 +1827,8 @@
# new requirements = old non-format requirements +
# new format-related
# requirements from the streamed-in repository
- requirements.update(self.requirements - self.supportedformats)
- self.requirements = requirements
+ self.requirements = requirements | (
+ self.requirements - self.supportedformats)
self._applyopenerreqs()
self._writerequirements()