completion: let 'ls-files' and 'diff-index' filter matching paths

During git-aware path completion, e.g. 'git rm dir/fil<TAB>', both
'git ls-files' and 'git diff-index' list all paths in the given 'dir/'
matching certain criteria (cached, modified, untracked, etc.)
appropriate for the given git command, even paths whose names don't
begin with 'fil'.  This comes with a considerable performance
penalty when the directory in question contains a lot of paths, but
the current word can be uniquely completed or when only a handful of
those paths match the current word.

Reduce the number of iterations in this codepath from the number of
paths to the number of matching paths by specifying an appropriate
globbing pattern to 'git ls-files' and 'git diff-index' to list only
paths that match the current word to be completed.

Note that both commands treat backslashes as escape characters in
their file arguments, e.g. to preserve the literal meaning of globbing
characters, so we have to double every backslash in the globbing
pattern.  This is why one of the path completion tests specifically
checks the completion of a path containing a literal backslash
character (that test still fails, though, because both commands output
such paths enclosed in double quotes and the special characters
escaped; a later patch in this series will deal with those).

This speeds up path completion considerably when there are a lot of
non-matching paths to be filtered out.  Uniquely completing a tracked
filename at the top of the worktree in linux.git (over 62k files),
i.e. what's doing all the hard work behind 'git rm Mak<TAB>' to
complete 'Makefile':

  Before this patch, best of five, on Linux:

    $ time cur=Mak __git_complete_index_file

    real    0m2.159s
    user    0m1.299s
    sys     0m1.089s

  After:

    real    0m0.033s
    user    0m0.023s
    sys     0m0.015s

  Difference: -98.5%
  Speedup:     65.4x

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2 files changed
tree: 5c187443055f08c49163d98cfa0bfc7dad649c57
  1. .github/
  2. block-sha1/
  3. builtin/
  4. ci/
  5. compat/
  6. contrib/
  7. Documentation/
  8. ewah/
  9. git-gui/
  10. gitk-git/
  11. gitweb/
  12. mergetools/
  13. perl/
  14. po/
  15. ppc/
  16. refs/
  17. sha1dc/
  18. t/
  19. templates/
  20. vcs-svn/
  21. xdiff/
  22. .clang-format
  23. .gitattributes
  24. .gitignore
  25. .gitmodules
  26. .mailmap
  27. .travis.yml
  28. .tsan-suppressions
  29. abspath.c
  30. aclocal.m4
  31. advice.c
  32. advice.h
  33. alias.c
  34. alloc.c
  35. apply.c
  36. apply.h
  37. archive-tar.c
  38. archive-zip.c
  39. archive.c
  40. archive.h
  41. argv-array.c
  42. argv-array.h
  43. attr.c
  44. attr.h
  45. base85.c
  46. bisect.c
  47. bisect.h
  48. blame.c
  49. blame.h
  50. blob.c
  51. blob.h
  52. branch.c
  53. branch.h
  54. builtin.h
  55. bulk-checkin.c
  56. bulk-checkin.h
  57. bundle.c
  58. bundle.h
  59. cache-tree.c
  60. cache-tree.h
  61. cache.h
  62. check-builtins.sh
  63. check-racy.c
  64. check_bindir
  65. checkout.c
  66. checkout.h
  67. color.c
  68. color.h
  69. column.c
  70. column.h
  71. combine-diff.c
  72. command-list.txt
  73. commit-slab.h
  74. commit.c
  75. commit.h
  76. common-main.c
  77. config.c
  78. config.h
  79. config.mak.in
  80. config.mak.uname
  81. configure.ac
  82. connect.c
  83. connect.h
  84. connected.c
  85. connected.h
  86. convert.c
  87. convert.h
  88. copy.c
  89. COPYING
  90. credential-cache--daemon.c
  91. credential-cache.c
  92. credential-store.c
  93. credential.c
  94. credential.h
  95. csum-file.c
  96. csum-file.h
  97. ctype.c
  98. daemon.c
  99. date.c
  100. decorate.c
  101. decorate.h
  102. delta.h
  103. diff-delta.c
  104. diff-lib.c
  105. diff-no-index.c
  106. diff.c
  107. diff.h
  108. diffcore-break.c
  109. diffcore-delta.c
  110. diffcore-order.c
  111. diffcore-pickaxe.c
  112. diffcore-rename.c
  113. diffcore.h
  114. dir-iterator.c
  115. dir-iterator.h
  116. dir.c
  117. dir.h
  118. editor.c
  119. entry.c
  120. environment.c
  121. exec_cmd.c
  122. exec_cmd.h
  123. fast-import.c
  124. fetch-object.c
  125. fetch-object.h
  126. fetch-pack.c
  127. fetch-pack.h
  128. fmt-merge-msg.h
  129. fsck.c
  130. fsck.h
  131. fsmonitor.c
  132. fsmonitor.h
  133. generate-cmdlist.sh
  134. gettext.c
  135. gettext.h
  136. git-add--interactive.perl
  137. git-archimport.perl
  138. git-bisect.sh
  139. git-compat-util.h
  140. git-cvsexportcommit.perl
  141. git-cvsimport.perl
  142. git-cvsserver.perl
  143. git-difftool--helper.sh
  144. git-filter-branch.sh
  145. git-instaweb.sh
  146. git-merge-octopus.sh
  147. git-merge-one-file.sh
  148. git-merge-resolve.sh
  149. git-mergetool--lib.sh
  150. git-mergetool.sh
  151. git-p4.py
  152. git-parse-remote.sh
  153. git-quiltimport.sh
  154. git-rebase--am.sh
  155. git-rebase--interactive.sh
  156. git-rebase--merge.sh
  157. git-rebase.sh
  158. git-remote-testgit.sh
  159. git-request-pull.sh
  160. git-send-email.perl
  161. git-sh-i18n.sh
  162. git-sh-setup.sh
  163. git-stash.sh
  164. git-submodule.sh
  165. git-svn.perl
  166. GIT-VERSION-GEN
  167. git-web--browse.sh
  168. git.c
  169. git.rc
  170. gpg-interface.c
  171. gpg-interface.h
  172. graph.c
  173. graph.h
  174. grep.c
  175. grep.h
  176. hash.h
  177. hashmap.c
  178. hashmap.h
  179. help.c
  180. help.h
  181. hex.c
  182. http-backend.c
  183. http-fetch.c
  184. http-push.c
  185. http-walker.c
  186. http.c
  187. http.h
  188. ident.c
  189. imap-send.c
  190. INSTALL
  191. iterator.h
  192. khash.h
  193. kwset.c
  194. kwset.h
  195. levenshtein.c
  196. levenshtein.h
  197. LGPL-2.1
  198. line-log.c
  199. line-log.h
  200. line-range.c
  201. line-range.h
  202. list-objects-filter-options.c
  203. list-objects-filter-options.h
  204. list-objects-filter.c
  205. list-objects-filter.h
  206. list-objects.c
  207. list-objects.h
  208. list.h
  209. ll-merge.c
  210. ll-merge.h
  211. lockfile.c
  212. lockfile.h
  213. log-tree.c
  214. log-tree.h
  215. mailinfo.c
  216. mailinfo.h
  217. mailmap.c
  218. mailmap.h
  219. Makefile
  220. match-trees.c
  221. merge-blobs.c
  222. merge-blobs.h
  223. merge-recursive.c
  224. merge-recursive.h
  225. merge.c
  226. mergesort.c
  227. mergesort.h
  228. name-hash.c
  229. notes-cache.c
  230. notes-cache.h
  231. notes-merge.c
  232. notes-merge.h
  233. notes-utils.c
  234. notes-utils.h
  235. notes.c
  236. notes.h
  237. object-store.h
  238. object.c
  239. object.h
  240. oidmap.c
  241. oidmap.h
  242. oidset.c
  243. oidset.h
  244. pack-bitmap-write.c
  245. pack-bitmap.c
  246. pack-bitmap.h
  247. pack-check.c
  248. pack-objects.c
  249. pack-objects.h
  250. pack-revindex.c
  251. pack-revindex.h
  252. pack-write.c
  253. pack.h
  254. packfile.c
  255. packfile.h
  256. pager.c
  257. parse-options-cb.c
  258. parse-options.c
  259. parse-options.h
  260. patch-delta.c
  261. patch-ids.c
  262. patch-ids.h
  263. path.c
  264. path.h
  265. pathspec.c
  266. pathspec.h
  267. pkt-line.c
  268. pkt-line.h
  269. preload-index.c
  270. pretty.c
  271. pretty.h
  272. prio-queue.c
  273. prio-queue.h
  274. progress.c
  275. progress.h
  276. prompt.c
  277. prompt.h
  278. protocol.c
  279. protocol.h
  280. quote.c
  281. quote.h
  282. reachable.c
  283. reachable.h
  284. read-cache.c
  285. README.md
  286. ref-filter.c
  287. ref-filter.h
  288. reflog-walk.c
  289. reflog-walk.h
  290. refs.c
  291. refs.h
  292. remote-curl.c
  293. remote-testsvn.c
  294. remote.c
  295. remote.h
  296. replace_object.c
  297. repository.c
  298. repository.h
  299. rerere.c
  300. rerere.h
  301. resolve-undo.c
  302. resolve-undo.h
  303. revision.c
  304. revision.h
  305. run-command.c
  306. run-command.h
  307. send-pack.c
  308. send-pack.h
  309. sequencer.c
  310. sequencer.h
  311. server-info.c
  312. setup.c
  313. sh-i18n--envsubst.c
  314. sha1-array.c
  315. sha1-array.h
  316. sha1-lookup.c
  317. sha1-lookup.h
  318. sha1_file.c
  319. sha1_name.c
  320. sha1dc_git.c
  321. sha1dc_git.h
  322. shallow.c
  323. shell.c
  324. shortlog.h
  325. show-index.c
  326. sideband.c
  327. sideband.h
  328. sigchain.c
  329. sigchain.h
  330. split-index.c
  331. split-index.h
  332. strbuf.c
  333. strbuf.h
  334. streaming.c
  335. streaming.h
  336. string-list.c
  337. string-list.h
  338. sub-process.c
  339. sub-process.h
  340. submodule-config.c
  341. submodule-config.h
  342. submodule.c
  343. submodule.h
  344. symlinks.c
  345. tag.c
  346. tag.h
  347. tar.h
  348. tempfile.c
  349. tempfile.h
  350. thread-utils.c
  351. thread-utils.h
  352. tmp-objdir.c
  353. tmp-objdir.h
  354. trace.c
  355. trace.h
  356. trailer.c
  357. trailer.h
  358. transport-helper.c
  359. transport-internal.h
  360. transport.c
  361. transport.h
  362. tree-diff.c
  363. tree-walk.c
  364. tree-walk.h
  365. tree.c
  366. tree.h
  367. unicode_width.h
  368. unimplemented.sh
  369. unix-socket.c
  370. unix-socket.h
  371. unpack-trees.c
  372. unpack-trees.h
  373. upload-pack.c
  374. url.c
  375. url.h
  376. urlmatch.c
  377. urlmatch.h
  378. usage.c
  379. userdiff.c
  380. userdiff.h
  381. utf8.c
  382. utf8.h
  383. varint.c
  384. varint.h
  385. version.c
  386. version.h
  387. versioncmp.c
  388. walker.c
  389. walker.h
  390. wildmatch.c
  391. wildmatch.h
  392. worktree.c
  393. worktree.h
  394. wrap-for-bin.sh
  395. wrapper.c
  396. write_or_die.c
  397. ws.c
  398. wt-status.c
  399. wt-status.h
  400. xdiff-interface.c
  401. xdiff-interface.h
  402. zlib.c
README.md

Git - fast, scalable, distributed revision control system

Git is a fast, scalable, distributed revision control system with an unusually rich command set that provides both high-level operations and full access to internals.

Git is an Open Source project covered by the GNU General Public License version 2 (some parts of it are under different licenses, compatible with the GPLv2). It was originally written by Linus Torvalds with help of a group of hackers around the net.

Please read the file INSTALL for installation instructions.

Many Git online resources are accessible from https://git-scm.com/ including full documentation and Git related tools.

See Documentation/gittutorial.txt to get started, then see Documentation/giteveryday.txt for a useful minimum set of commands, and Documentation/git-.txt for documentation of each command. If git has been correctly installed, then the tutorial can also be read with man gittutorial or git help tutorial, and the documentation of each command with man git-<commandname> or git help <commandname>.

CVS users may also want to read Documentation/gitcvs-migration.txt (man gitcvs-migration or git help cvs-migration if git is installed).

The user discussion and development of Git take place on the Git mailing list -- everyone is welcome to post bug reports, feature requests, comments and patches to git@vger.kernel.org (read Documentation/SubmittingPatches for instructions on patch submission). To subscribe to the list, send an email with just “subscribe git” in the body to majordomo@vger.kernel.org. The mailing list archives are available at https://public-inbox.org/git/, http://marc.info/?l=git and other archival sites.

The maintainer frequently sends the “What's cooking” reports that list the current status of various development topics to the mailing list. The discussion following them give a good reference for project status, development direction and remaining tasks.

The name “git” was given by Linus Torvalds when he wrote the very first version. He described the tool as “the stupid content tracker” and the name as (depending on your mood):

  • random three-letter combination that is pronounceable, and not actually used by any common UNIX command. The fact that it is a mispronunciation of “get” may or may not be relevant.
  • stupid. contemptible and despicable. simple. Take your pick from the dictionary of slang.
  • “global information tracker”: you're in a good mood, and it actually works for you. Angels sing, and a light suddenly fills the room.
  • “goddamn idiotic truckload of sh*t”: when it breaks