largefiles: align rm warnings with warnings used in core

merge with stable

largefiles: commit directories that only contain largefiles (issue3548) If we pass a directory to commit whose only commitable files are largefiles, the core commit code aborts before finding the largefiles. So we do the following: For directories that only have largefiles as matches, we explicitly add the largefiles to the matchlist and remove the directory. In other cases, we leave the match list unmodified.

revset.children: ignore rev numbers that are too low This replaces unnecessary parentrevs() calls with calculating min(parentset). Even though the min operation is O(size of parentset), since parentrevs is relatively expensive, this tradeoff almost always works in our favour. In a repository with over 400,000 changesets, hg perfrevset "children(X)" takes: Set X Before After -1 0.51s 0.06s -1000: 0.55s 0.08s -10000: 0.56s 0.10s -100000: 0.60s 0.25s -100000:-99000 0.55s 0.19s 0:100000 0.60s 0.61s all() 0.72s 0.74s The relative performance is similar for Mercurial's own repository -- several times faster in most cases, slightly slower for revisions close to 0 and all().

perf: add a command to measure revset performance

run-tests: fix whitespace nonsense

merge with mpm

run-tests: on windows, put correct python at front of PATH The older approach of trying to copy the python executable into the test directory was doomed to fail. There remains one weakness with this approach: if you've run "make local", tests may pick up the wrong extension DLLs from inside the source tree. I don't know why this happens. A reasonable workaround for now is to test either using --local or with a working directory that does not contain built DLLs.

run-tests: fix exename on Windows

run-tests: support running tests in parallel on windows Previously, we used os.spawnvp, which doesn't exist on Windows, and isn't needed anyway (the command line begins with an absolute path). We also need a slightly more convoluted way to wait for processes without specifying an order on Windows, as it lacks os.wait.