Documentation / RelNotes / 2.5.0.txton commit builtin/show-ref: rewrite to use object_id (f0a011f)
   1Git 2.5 Release Notes
   2=====================
   3
   4Updates since v2.4
   5------------------
   6
   7Ports
   8
   9
  10UI, Workflows & Features
  11
  12 * "git p4" now detects the filetype (e.g. binary) correctly even when
  13   the files are opened exclusively.
  14
  15 * git p4 attempts to better handle branches in Perforce.
  16
  17 * "git p4" learned "--changes-block-size <n>" to read the changes in
  18   chunks from Perforce, instead of making one call to "p4 changes"
  19   that may trigger "too many rows scanned" error from Perforce.
  20
  21 * "git show-branch --topics HEAD" (with no other arguments) did not
  22   do anything interesting.  Instead, contrast the given revision
  23   against all the local branches by default.
  24
  25 * A replacement for contrib/workdir/git-new-workdir that does not
  26   rely on symbolic links and make sharing of objects and refs safer
  27   by making the borrowee and borrowers aware of each other.
  28
  29 * Tweak the sample "store" backend of the credential helper to honor
  30   XDG configuration file locations when specified.
  31
  32 * A heuristic to help the "git <cmd> <revs> <pathspec>" command line
  33   convention to catch mistyped paths is to make sure all the non-rev
  34   parameters in the later part of the command line are names of the
  35   files in the working tree, but that means "git grep $str -- \*.c"
  36   must always be disambiguated with "--", because nobody sane will
  37   create a file whose name literally is asterisk-dot-see.  Loosen the
  38   heuristic to declare that with a wildcard string the user likely
  39   meant to give us a pathspec.
  40
  41 * "git merge FETCH_HEAD" learned that the previous "git fetch" could
  42   be to create an Octopus merge, i.e. recording multiple branches
  43   that are not marked as "not-for-merge"; this allows us to lose an
  44   old style invocation "git merge <msg> HEAD $commits..." in the
  45   implementation of "git pull" script; the old style syntax can now
  46   be deprecated.
  47
  48 * Help us to find broken test script that splits the body part of the
  49   test by mistaken use of wrong kind of quotes.
  50   (merge d93d5d5 jc/test-prereq-validate later to maint).
  51
  52 * Developer support to automatically detect broken &&-chain in the
  53   test scripts is now turned on by default.
  54   (merge 92b269f jk/test-chain-lint later to maint).
  55
  56 * Filter scripts were run with SIGPIPE disabled on the Git side,
  57   expecting that they may not read what Git feeds them to filter.
  58   We however treated a filter that does not read its input fully
  59   before exiting as an error.
  60
  61   This changes semantics, but arguably in a good way.  If a filter
  62   can produce its output without consuming its input using whatever
  63   magic, we now let it do so, instead of diagnosing it as a
  64   programming error.
  65
  66 * Instead of dying immediately upon failing to obtain a lock, the
  67   locking (of refs etc) retries after a short while with backoff.
  68
  69 * Introduce http.<url>.SSLCipherList configuration variable to tweak
  70   the list of cipher suite to be used with libcURL when talking with
  71   https:// sites.
  72
  73 * "git subtree" script (in contrib/) used "echo -n" to produce
  74   progress messages in a non-portable way.
  75
  76 * "git subtree" script (in contrib/) does not have --squash option
  77   when pushing, but the documentation and help text pretended as if
  78   it did.
  79
  80 * The Git subcommand completion (in contrib/) listed credential
  81   helpers among candidates, which is not something the end user would
  82   invoke interatively.
  83
  84
  85Performance, Internal Implementation, Development Support etc.
  86
  87 * "unsigned char [20]" used thoughout the code to represent object
  88   names are being converted into a semi-opaque "struct object_id".
  89   This effort is expected to interfere with other topics in flight,
  90   but hopefully will give us one extra level of abstraction in the
  91   end, when completed.
  92
  93 * Catch a programmer mistake to feed a pointer not an array to
  94   ARRAY_SIZE() macro, by using a couple of GCC extensions.
  95   (merge 89c855e ep/do-not-feed-a-pointer-to-array-size later to maint).
  96
  97 * Some error messages in "git config" were emitted without calling
  98   the usual error() facility.
  99
 100 * When "add--interactive" splits a hunk into two overlapping hunks
 101   and then let the user choose only one, it sometimes feeds an
 102   incorrect patch text to "git apply".  Add tests to demonstrate
 103   this.
 104
 105   I have a slight suspicion that this may be $gmane/87202 coming back
 106   and biting us (I seem to have said "let's run with this and see
 107   what happens" back then).
 108
 109 * More line-ending tests.
 110
 111 * An earlier rewrite to use strbuf_getwholeline() instead of fgets(3)
 112   to read packed-refs file revealed that the former is unacceptably
 113   inefficient.
 114
 115 * The refs API uses ref_lock struct which had its own "int fd", even
 116   though the same file descriptor was in the lock struct it contains.
 117   Clean-up the code to lose this redundant field.
 118
 119 * Add the "--allow-unknown-type" option to "cat-file" to allow
 120   inspecting loose objects of an experimental or a broken type.
 121
 122 * Many long-running operations show progress eye-candy, even when
 123   they are later backgrounded.  Hide the eye-candy when the process
 124   is sent to the background instead.
 125   (merge 9a9a41d lm/squelch-bg-progress later to maint).
 126
 127 * There was a dead code that used to handle "git pull --tags" and
 128   show special-cased error message, which was made irrelevant when
 129   the semantics of the option changed back in Git 1.9 days.
 130   (merge 19d122b pt/pull-tags-error-diag later to maint).
 131
 132
 133Also contains various documentation updates and code clean-ups.
 134
 135
 136Fixes since v2.4
 137----------------
 138
 139Unless otherwise noted, all the fixes since v2.4 in the maintenance
 140track are contained in this release (see the maintenance releases'
 141notes for details).
 142
 143 * Git 2.4 broke setting verbosity and progress levels on "git clone"
 144   with native transports.
 145   (merge 822f0c4 mh/clone-verbosity-fix later to maint).
 146
 147 * "git add -e" did not allow the user to abort the operation by
 148   killing the editor.
 149   (merge cb64800 jk/add-e-kill-editor later to maint).
 150
 151 * Memory usage of "git index-pack" has been trimmed by tens of
 152   per-cent.
 153   (merge c6458e6 nd/slim-index-pack-memory-usage later to maint).
 154
 155 * "git rev-list --objects $old --not --all" to see if everything that
 156   is reachable from $old is already connected to the existing refs
 157   was very inefficient.
 158   (merge b6e8a3b jk/still-interesting later to maint).
 159
 160 * "hash-object --literally" introduced in v2.2 was not prepared to
 161   take a really long object type name.
 162   (merge 1427a7f jc/hash-object later to maint).
 163
 164 * "git rebase --quiet" was not quite quiet when there is nothing to
 165   do.
 166   (merge 22946a9 jk/rebase-quiet-noop later to maint).
 167
 168 * The completion for "log --decorate=" parameter value was incorrect.
 169   (merge af16bda sg/complete-decorate-full-not-long later to maint).
 170
 171 * "filter-branch" corrupted commit log message that ends with an
 172   incomplete line on platforms with some "sed" implementations that
 173   munge such a line.  Work it around by avoiding to use "sed".
 174   (merge df06201 jk/filter-branch-use-of-sed-on-incomplete-line later to maint).
 175
 176 * "git daemon" fails to build from the source under NO_IPV6
 177   configuration (regression in 2.4).
 178   (merge d358f77 jc/daemon-no-ipv6-for-2.4.1 later to maint).
 179
 180 * Some time ago, "git blame" (incorrectly) lost the convert_to_git()
 181   call when synthesizing a fake "tip" commit that represents the
 182   state in the working tree, which broke folks who record the history
 183   with LF line ending to make their project portabile across
 184   platforms while terminating lines in their working tree files with
 185   CRLF for their platform.
 186   (merge 4bf256d tb/blame-resurrect-convert-to-git later to maint).
 187
 188 * We avoid setting core.worktree when the repository location is the
 189   ".git" directory directly at the top level of the working tree, but
 190   the code misdetected the case in which the working tree is at the
 191   root level of the filesystem (which arguably is a silly thing to
 192   do, but still valid).
 193   (merge 84ccad8 jk/init-core-worktree-at-root later to maint).
 194
 195 * "git commit --date=now" or anything that relies on approxidate lost
 196   the daylight-saving-time offset.
 197   (merge f6e6362 jc/epochtime-wo-tz later to maint).
 198
 199 * Access to objects in repositories that borrow from another one on a
 200   slow NFS server unnecessarily got more expensive due to recent code
 201   becoming more cautious in a naive way not to lose objects to pruning.
 202   (merge ee1c6c3 jk/prune-mtime later to maint).
 203
 204 * The codepaths that read .gitignore and .gitattributes files have been
 205   taught that these files encoded in UTF-8 may have UTF-8 BOM marker at
 206   the beginning; this makes it in line with what we do for configuration
 207   files already.
 208   (merge 27547e5 cn/bom-in-gitignore later to maint).
 209
 210 * a few helper scripts in the test suite did not report errors
 211   correcty.
 212   (merge de248e9 ep/fix-test-lib-functions-report later to maint).
 213
 214 * The default $HOME/.gitconfig file created upon "git config --global"
 215   that edits it had incorrectly spelled user.name and user.email
 216   entries in it.
 217   (merge 7e11052 oh/fix-config-default-user-name-section later to maint).
 218
 219 * "git cat-file bl $blob" failed to barf even though there is no
 220   object type that is "bl".
 221   (merge b7994af jk/type-from-string-gently later to maint).
 222
 223 * The usual "git diff" when seeing a file turning into a directory
 224   showed a patchset to remove the file and create all files in the
 225   directory, but "git diff --no-index" simply refused to work.  Also,
 226   when asked to compare a file and a directory, imitate POSIX "diff"
 227   and compare the file with the file with the same name in the
 228   directory, instead of refusing to run.
 229   (merge 0615173 jc/diff-no-index-d-f later to maint).
 230
 231 * "git rebase -i" moved the "current" command from "todo" to "done" a
 232   bit too prematurely, losing a step when a "pick" did not even start.
 233   (merge 8cbc57c ph/rebase-i-redo later to maint).
 234
 235 * The connection initiation code for "ssh" transport tried to absorb
 236   differences between the stock "ssh" and Putty-supplied "plink" and
 237   its derivatives, but the logic to tell that we are using "plink"
 238   variants were too loose and falsely triggered when "plink" appeared
 239   anywhere in the path (e.g. "/home/me/bin/uplink/ssh").
 240   (merge baaf233 bc/connect-plink later to maint).
 241
 242 * "git stash pop/apply" forgot to make sure that not just the working
 243   tree is clean but also the index is clean. The latter is important
 244   as a stash application can conflict and the index will be used for
 245   conflict resolution.
 246   (merge ed178ef jk/stash-require-clean-index later to maint).
 247
 248 * We have prepended $GIT_EXEC_PATH and the path "git" is installed in
 249   (typically "/usr/bin") to $PATH when invoking subprograms and hooks
 250   for almost eternity, but the original use case the latter tried to
 251   support was semi-bogus (i.e. install git to /opt/foo/git and run it
 252   without having /opt/foo on $PATH), and more importantly it has
 253   become less and less relevant as Git grew more mainstream (i.e. the
 254   users would _want_ to have it on their $PATH).  Stop prepending the
 255   path in which "git" is installed to users' $PATH, as that would
 256   interfere the command search order people depend on (e.g. they may
 257   not like versions of programs that are unrelated to Git in /usr/bin
 258   and want to override them by having different ones in /usr/local/bin
 259   and have the latter directory earlier in their $PATH).
 260   (merge a0b4507 jk/git-no-more-argv0-path-munging later to maint).
 261
 262 * core.excludesfile (defaulting to $XDG_HOME/git/ignore) is supposed
 263   to be overridden by repository-specific .git/info/exclude file, but
 264   the order was swapped from the beginning. This belatedly fixes it.
 265   (merge 099d2d8 jc/gitignore-precedence later to maint).
 266
 267 * After "git add -N", the path appeared in output of "git diff HEAD"
 268   and "git diff --cached HEAD", leading "git status" to classify it
 269   as "Changes to be committed".  Such a path, however, is not yet to
 270   be scheduled to be committed.  "git diff" showed the change to the
 271   path as modification, not as a "new file", in the header of its
 272   output.
 273
 274   Treat such paths as "yet to be added to the index but Git already
 275   know about them"; "git diff HEAD" and "git diff --cached HEAD"
 276   should not talk about them, and "git diff" should show them as new
 277   files yet to be added to the index.
 278   (merge d95d728 nd/diff-i-t-a later to maint).
 279
 280 * There was a commented-out (instead of being marked to expect
 281   failure) test that documented a breakage that was fixed since the
 282   test was written; turn it into a proper test.
 283   (merge 66d2e04 sb/t1020-cleanup later to maint).
 284
 285 * The "log --decorate" enhancement in Git 2.4 that shows the commit
 286   at the tip of the current branch e.g. "HEAD -> master", did not
 287   work with --decorate=full.
 288   (merge 429ad20 mg/log-decorate-HEAD later to maint).
 289
 290 * The ref API did not handle cases where 'refs/heads/xyzzy/frotz' is
 291   removed at the same time as 'refs/heads/xyzzy' is added (or vice
 292   versa) very well.
 293   (merge c628edf mh/ref-directory-file later to maint).
 294
 295 * Multi-ref transaction support we merged a few releases ago
 296   unnecessarily kept many file descriptors open, risking to fail with
 297   resource exhaustion.  This is for 2.4.x track.
 298   (merge 185ce3a mh/write-refs-sooner-2.4 later to maint).
 299
 300 * "git bundle verify" did not diagnose extra parameters on the
 301   command line.
 302   (merge 7886cfa ps/bundle-verify-arg later to maint).
 303
 304 * Various documentation mark-up fixes to make the output more
 305   consistent in general and also make AsciiDoctor (an alternative
 306   formatter) happier.
 307   (merge d0258b9 jk/asciidoc-markup-fix later to maint).
 308   (merge ad3967a jk/stripspace-asciidoctor-fix later to maint).
 309   (merge 975e382 ja/tutorial-asciidoctor-fix later to maint).
 310
 311 * Code cleanups and documentation updates.
 312   (merge 0269f96 mm/usage-log-l-can-take-regex later to maint).
 313   (merge 64f2589 nd/t1509-chroot-test later to maint).
 314   (merge f86a374 sb/test-bitmap-free-at-end later to maint).
 315   (merge 05bfc7d sb/line-log-plug-pairdiff-leak later to maint).
 316   (merge 846e5df pt/xdg-config-path later to maint).
 317   (merge 1154aa4 jc/plug-fmt-merge-msg-leak later to maint).
 318   (merge 319b678 jk/sha1-file-reduce-useless-warnings later to maint).
 319   (merge 9a35c14 fg/document-commit-message-stripping later to maint).
 320   (merge bbf431c ps/doc-packfile-vs-pack-file later to maint).
 321   (merge 309a9e3 jk/skip-http-tests-under-no-curl later to maint).
 322   (merge ccd593c dl/branch-error-message later to maint).