match: define exactmatcher.matchfn statically This should eliminate the reference cycle, self.matchfn -> self.exact -> self.

match: remove override of prefix() from differencematcher It's exactly the same as basematcher.prefix().

cat: do not start pager if output will be written to file

cat: pass filename template as explicit argument I'll move the handling of the '-' filename to commands.cat().

cmdutil: extract function checking if pattern should be taken as stdin/out This will be used in commands.cat().

cmdutil: drop deprecated hack to pass file object to makefileobj() (API) All callers pass a string 'pat' or None.

encoding: make sure "wide" variable never be referenced from other modules Better to not expose (maybe-) unicode objects.

manifest: use itertools.chain() instead of + for Python 3 compat This is all pure-Python code, so I'm not too worried about perf here, but we can come back and fix it should it be a problem. With this change, the manifest code passes most unit tests on Python 3 (once the tests are corrected with many b prefixes. I've got a little more to sort out there and then I'll mail that change too.

manifest: fix some pure-Python parser bits to work on Python 3

tests: make test-manifest finish importing in Python 3 The test is still broken, but now it executes.