util: add a doctest for empty sha() calls

largefiles: replace tempfile.NamedTemporaryFile with tempfile.mkstemp This is consistent with the rest of Mercurial's code, mirroring the try-finally-unlink structure elsewhere. Furthermore, it fixes the case where largefiles throws an IOError on Windows when the temporary file is opened a second time by copytocacheabsolute. This patch creates the temporary file in the repo's largefiles store rather than /tmp, which might be a different filesystem.

util: allow sha1() with no args Normally this works because we replace util.sha1 with hashlib.sha1 after first use, but if the first user doesn't provide an arg, it breaks.

tests: use md5sum.py instead of sha1sum, add check

setup: set whole env for running hg even if .hg doesn't exist (issue3073) The issue was partially fixed by b357a972d6cd, but there were missing variables to run build_hgextindex.

keyword: backout realpath change (issue3071)

strip: backout 73307643a09f (issue3077)

largefiles: avoid checking requirements on every command When largefiles is enabled, commands on large repositories which don't require largefiles could be slowed down substantially. Disable checking this for every command.

largefiles: shorten test suite by using log --template

largefiles: fix bad bug where transplanting a changeset with a largefile will result in an old largefile being comitted later on