py3: port metaedit extension to Python 3 Without these changes, this extension is responsible for a test of test failures. Differential Revision: https://phab.mercurial-scm.org/D2150

py3: pass system string to email.message.Message.set_type() Python 3 insists the type is a str. Differential Revision: https://phab.mercurial-scm.org/D2149

py3: open temporary file in binary mode Otherwise things fail later when we write bytes to the handle. Differential Revision: https://phab.mercurial-scm.org/D2148

py3: use email parser that operates on bytes email.parser.Parser() operates on str in both Python 2 and 3. Python 3.2 introduced the email.parser.BytesParser(), which works like Parser except it accepts bytes. We implement the pycompat helper as a function so we lazily import the "email" module. Differential Revision: https://phab.mercurial-scm.org/D2147

py3: port ext-phase-report.py extension The custom module importer doesn't run on Python files in the tests directory. So we need the source to be compatible with both Python 2 and 3. Differential Revision: https://phab.mercurial-scm.org/D2145

py3: more robustly cast UUID to bytes The UUID type only has __str__ implemented. So we need to cast to bytes on Python 3. We need an actual bytes instance here (bytestr won't do) because the re.escape() later iterates over characters and characters need to behave like ints, not bytes instances of length 1. Differential Revision: https://phab.mercurial-scm.org/D2144