pathcomplete: complete directories more conservatively Suppose we want to perform a single-level completion (i.e. without --full) of "fi" in a repo containing "fee", "fie/dead", "fie/live", and "foe". If we give back "fie/" as the only answer, the shell will consider the completion to be unambiguous, and will append a space after the completion. We can't complete "fie/live" or "fie/dead" without first backspacing over that space. We used to thus create two fake names, "fie/a" and "fie/b", to force the shell to consider the completion to be ambiguous. It would then stop at "fie/" without appending a space, allowing us to hit tab again to complete "fie/live" or "fie/dead". The change here arises from realising that we only need to force the shell to consider a completion as ambiguous if we have exactly one directory and zero files as possible completions. This prevents spurious names from showing up as possible completions when they don't need to be invented in the first place.

sadclown: another test failure eluded me

bash_completion: recognize normal command abbreviations In many common cases, this eliminates a call to "hg help" to get a complete command name, thus improving responsiveness.

completion: selectively use debugpathcomplete in bash_completion The current bash_completion code can be very slow in a large working directory. It always uses "hg status" to generate possibly matching files, which checks the status of every file. We often don't care about status when completing, so that cost is very high. As the new debugpathcomplete command does not check the status of files, it offers much better performance for commands that only care about completing names.

completion: add a debugpathcomplete command The bash_completion code uses "hg status" to generate a list of possible completions for commands that operate on files in the working directory. In a large working directory, this can result in a single tab-completion being very slow (several seconds) as a result of checking the status of every file, even when there is no need to check status or no possible matches. The new debugpathcomplete command gains performance in a few simple ways: * Allow completion to operate on just a single directory. When used to complete the right commands, this considerably reduces the number of completions returned, at no loss in functionality. * Never check the status of files. For completions that really must know if a file is modified, it is faster to use status: hg status -nm 'glob:myprefix**' Performance: Here are the commands used by bash_completion to complete, run in the root of the mozilla-central working dir (~77,000 files) and another repo (~165,000 files): All "normal state" files (used by e.g. remove, revert): mozilla other status -nmcd 'glob:**' 1.77 4.10 sec debugpathcomplete -f -n 0.53 1.26 debugpathcomplete -n 0.17 0.41 ("-f" means "complete full paths", rather than the current directory) Tracked files matching "a": mozilla other status -nmcd 'glob:a**' 0.26 0.47 debugpathcomplete -f -n a 0.10 0.24 debugpathcomplete -n a 0.10 0.22 We should be able to further improve completion performance once the critbit work lands. Right now, our performance is limited by the need to iterate over all keys in the dirstate.

tests: add new command to test-debugcomplete

completion: add a debuglabelcomplete command When completing a "label" (a symbolic name for a commit), the bash_completion script currently has to invoke hg three times. For a large repository, the cost of starting up and loading all the necessary context over and over is very high. For instance, in mozilla-central: time (export HGPLAIN=1; hg tags -q; hg bookmarks -q; hg branches) >/dev/null 0.446 sec Compare with the debuglabelcomplete command that this commit adds: time hg debuglabelcomplete >/dev/null 0.148 sec This greatly helps responsiveness.