py3: convert log opts to bytes-key dict Now simple log command works.

graphlog: pass function arguments without expansion It's annoying on Python 3 because keys must be unicode type. Let's stop using **opts expansion when not necessary.

py3: call codecs.escape_decode() directly The same rule as 3b7a6941a6ef applies.

util: wrap s.decode('string_escape') calls for future py3 compatibility

merge with stable

hgwebdir: add support for explicit index files This is useful for when repositories are nested in --web-conf, and in the future with hosted subrepositories. The previous behavior was only to render an index at each virtual directory. There is now an explicit 'index' child for each virtual directory. The name was suggested by Yuya, for consistency with the other method names. Additionally, there is now an explicit 'index' child for every repository directory with a nested repository somewhere below it. This seems more consistent with each virtual directory hosting an index, and more discoverable than to only have an index for a directory that directly hosts a nested repository. I couldn't figure out how to close the loop and provide one in each directory without a deeper nested repository, without blocking a committed 'index' file. Keeping that seems better than rendering an empty index.

ui: move configlist parser to config.py The list parser is complex and reusable without ui. Let's move it to config.py. This allows us to parse a list from a "pure" config object without going through ui. Like, we can make "_trustusers" calculated from raw configs, instead of making sure it's synchronized by calling "fixconfig"s.

tests: allow ModuleNotFoundError in addition to ImportError My environment (Python version? PYTHONPATH? something else?) raises ModuleNotFoundError in test-check-py3-compat.t. This patch allows any "*Error". The error string contains "error importing", so it seems specific enough even after.

pager: skip running the pager if it's set to 'cat' Avoid useless uses of cat.

pager: avoid shell=True on subprocess.Popen for better errors (issue5491) man(1) behaves as poorly as Mercurial without this change. This cribs from git's run-command[0], which has a list of characters that imply a string that needs to be run using 'sh -c'. If none of those characters are present in the command string, we can use shell=False mode on subprocess and get significantly better error messages (see the test) when the pager process is invalid. With a complicated pager command (that contains one of the unsafe characters), we behave as we do today (which is no worse than git manages.) I briefly tried tapdancing in a thread to catch early pager exits, but it's just too perilous: you get races between fd duping operations and a bad pager exiting, and it's too hard to differentiate between a slow-bad-pager result and a fast-human-quit-pager-early result. I've observed some weird variation in exit code handling in the "bad experience" case in test-pager.t: on my Mac hg predictably exits nonzero, but on Linux hg always exits zero in that case. For now, we'll work around it with || true. :( 0: https://github.com/git/git/blob/cddbda4bc87b9d2c985b6749b1cf026b15e2d3e7/run-command.c#L201