git-apply: Loosen "match_beginning" logic

Even after a handfle attempts, match_beginning logic still has corner
cases:

    1bf1a85 (apply: treat EOF as proper context., 2006-05-23)
    65aadb9 (apply: force matching at the beginning., 2006-05-24)
    4be6096 (apply --unidiff-zero: loosen sanity checks ..., 2006-09-17)
    ee5a317 (Fix "git apply" to correctly enforce "match ..., 2008-04-06)

This is a tricky piece of code.

We still incorrectly enforce "match_beginning" for -U0 matches.
I noticed this while trying out an example sequence from Clemens Buchacher:

    $ echo a >victim
    $ git add victim
    $ echo b >>victim
    $ git diff -U0 >patch
    $ cat patch
    diff --git i/victim w/victim
    index 7898192..422c2b7 100644
    --- i/victim
    +++ w/victim
    @@ -1,0 +2 @@ a
    +b
    $ git apply --cached --unidiff-zero <patch
    $ git show :victim
    b
    a

The change inserts a new line before the second line, but we insist it to
be applied at the beginning.  As the result, the code refuses to apply it
at the original offset, and we end up adding the line at the beginning.

Updates to the test script are by Clemens Buchacher.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2 files changed
tree: 2ede2745b8611c76ac76b7b9e240a1e092b87f84
  1. arm/
  2. compat/
  3. contrib/
  4. Documentation/
  5. git-gui/
  6. gitk-git/
  7. gitweb/
  8. mozilla-sha1/
  9. perl/
  10. ppc/
  11. t/
  12. templates/
  13. xdiff/
  14. .gitattributes
  15. .gitignore
  16. .mailmap
  17. abspath.c
  18. alias.c
  19. alloc.c
  20. archive-tar.c
  21. archive-zip.c
  22. archive.c
  23. archive.h
  24. attr.c
  25. attr.h
  26. base85.c
  27. blob.c
  28. blob.h
  29. branch.c
  30. branch.h
  31. builtin-add.c
  32. builtin-annotate.c
  33. builtin-apply.c
  34. builtin-archive.c
  35. builtin-blame.c
  36. builtin-branch.c
  37. builtin-bundle.c
  38. builtin-cat-file.c
  39. builtin-check-attr.c
  40. builtin-check-ref-format.c
  41. builtin-checkout-index.c
  42. builtin-checkout.c
  43. builtin-clean.c
  44. builtin-clone.c
  45. builtin-commit-tree.c
  46. builtin-commit.c
  47. builtin-config.c
  48. builtin-count-objects.c
  49. builtin-describe.c
  50. builtin-diff-files.c
  51. builtin-diff-index.c
  52. builtin-diff-tree.c
  53. builtin-diff.c
  54. builtin-fast-export.c
  55. builtin-fetch--tool.c
  56. builtin-fetch-pack.c
  57. builtin-fetch.c
  58. builtin-fmt-merge-msg.c
  59. builtin-for-each-ref.c
  60. builtin-fsck.c
  61. builtin-gc.c
  62. builtin-grep.c
  63. builtin-http-fetch.c
  64. builtin-init-db.c
  65. builtin-log.c
  66. builtin-ls-files.c
  67. builtin-ls-remote.c
  68. builtin-ls-tree.c
  69. builtin-mailinfo.c
  70. builtin-mailsplit.c
  71. builtin-merge-base.c
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  80. builtin-prune-packed.c
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  82. builtin-push.c
  83. builtin-read-tree.c
  84. builtin-reflog.c
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  86. builtin-rerere.c
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  88. builtin-rev-list.c
  89. builtin-rev-parse.c
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  91. builtin-rm.c
  92. builtin-send-pack.c
  93. builtin-shortlog.c
  94. builtin-show-branch.c
  95. builtin-show-ref.c
  96. builtin-stripspace.c
  97. builtin-symbolic-ref.c
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  99. builtin-tar-tree.c
  100. builtin-unpack-objects.c
  101. builtin-update-index.c
  102. builtin-update-ref.c
  103. builtin-upload-archive.c
  104. builtin-verify-pack.c
  105. builtin-verify-tag.c
  106. builtin-write-tree.c
  107. builtin.h
  108. bundle.c
  109. bundle.h
  110. cache-tree.c
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  112. cache.h
  113. check-builtins.sh
  114. check-racy.c
  115. check_bindir
  116. color.c
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  118. combine-diff.c
  119. command-list.txt
  120. commit.c
  121. commit.h
  122. config.c
  123. config.mak.in
  124. configure.ac
  125. connect.c
  126. convert.c
  127. copy.c
  128. COPYING
  129. csum-file.c
  130. csum-file.h
  131. ctype.c
  132. daemon.c
  133. date.c
  134. decorate.c
  135. decorate.h
  136. delta.h
  137. diff-delta.c
  138. diff-lib.c
  139. diff-no-index.c
  140. diff.c
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  142. diffcore-break.c
  143. diffcore-delta.c
  144. diffcore-order.c
  145. diffcore-pickaxe.c
  146. diffcore-rename.c
  147. diffcore.h
  148. dir.c
  149. dir.h
  150. dump-cache-tree.c
  151. editor.c
  152. entry.c
  153. environment.c
  154. exec_cmd.c
  155. exec_cmd.h
  156. fast-import.c
  157. fetch-pack.h
  158. fixup-builtins
  159. fsck.c
  160. fsck.h
  161. generate-cmdlist.sh
  162. git-add--interactive.perl
  163. git-am.sh
  164. git-archimport.perl
  165. git-bisect.sh
  166. git-compat-util.h
  167. git-cvsexportcommit.perl
  168. git-cvsimport.perl
  169. git-cvsserver.perl
  170. git-filter-branch.sh
  171. git-instaweb.sh
  172. git-lost-found.sh
  173. git-merge-octopus.sh
  174. git-merge-one-file.sh
  175. git-merge-resolve.sh
  176. git-mergetool.sh
  177. git-parse-remote.sh
  178. git-pull.sh
  179. git-quiltimport.sh
  180. git-rebase--interactive.sh
  181. git-rebase.sh
  182. git-relink.perl
  183. git-repack.sh
  184. git-request-pull.sh
  185. git-send-email.perl
  186. git-sh-setup.sh
  187. git-stash.sh
  188. git-submodule.sh
  189. git-svn.perl
  190. GIT-VERSION-GEN
  191. git-web--browse.sh
  192. git.c
  193. git.spec.in
  194. graph.c
  195. graph.h
  196. grep.c
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  198. hash-object.c
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  201. help.c
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  203. http-walker.c
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  206. ident.c
  207. imap-send.c
  208. index-pack.c
  209. INSTALL
  210. interpolate.c
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  212. list-objects.c
  213. list-objects.h
  214. ll-merge.c
  215. ll-merge.h
  216. lockfile.c
  217. log-tree.c
  218. log-tree.h
  219. mailmap.c
  220. mailmap.h
  221. Makefile
  222. match-trees.c
  223. merge-file.c
  224. merge-index.c
  225. merge-recursive.h
  226. merge-tree.c
  227. mktag.c
  228. mktree.c
  229. name-hash.c
  230. object.c
  231. object.h
  232. pack-check.c
  233. pack-redundant.c
  234. pack-refs.c
  235. pack-refs.h
  236. pack-revindex.c
  237. pack-revindex.h
  238. pack-write.c
  239. pack.h
  240. pager.c
  241. parse-options.c
  242. parse-options.h
  243. patch-delta.c
  244. patch-id.c
  245. patch-ids.c
  246. patch-ids.h
  247. path.c
  248. pkt-line.c
  249. pkt-line.h
  250. pretty.c
  251. progress.c
  252. progress.h
  253. quote.c
  254. quote.h
  255. reachable.c
  256. reachable.h
  257. read-cache.c
  258. README
  259. receive-pack.c
  260. reflog-walk.c
  261. reflog-walk.h
  262. refs.c
  263. refs.h
  264. remote.c
  265. remote.h
  266. rerere.c
  267. rerere.h
  268. revision.c
  269. revision.h
  270. run-command.c
  271. run-command.h
  272. send-pack.h
  273. server-info.c
  274. setup.c
  275. sha1-lookup.c
  276. sha1-lookup.h
  277. sha1_file.c
  278. sha1_name.c
  279. shallow.c
  280. shell.c
  281. shortlog.h
  282. show-index.c
  283. sideband.c
  284. sideband.h
  285. strbuf.c
  286. strbuf.h
  287. string-list.c
  288. string-list.h
  289. symlinks.c
  290. tag.c
  291. tag.h
  292. tar.h
  293. test-chmtime.c
  294. test-date.c
  295. test-delta.c
  296. test-genrandom.c
  297. test-match-trees.c
  298. test-parse-options.c
  299. test-path-utils.c
  300. test-sha1.c
  301. test-sha1.sh
  302. thread-utils.c
  303. thread-utils.h
  304. trace.c
  305. transport.c
  306. transport.h
  307. tree-diff.c
  308. tree-walk.c
  309. tree-walk.h
  310. tree.c
  311. tree.h
  312. unpack-file.c
  313. unpack-trees.c
  314. unpack-trees.h
  315. update-server-info.c
  316. upload-pack.c
  317. usage.c
  318. utf8.c
  319. utf8.h
  320. var.c
  321. walker.c
  322. walker.h
  323. wrapper.c
  324. write_or_die.c
  325. ws.c
  326. wt-status.c
  327. wt-status.h
  328. xdiff-interface.c
  329. xdiff-interface.h