Documentation / RelNotes / 2.8.0.txton commit Merge branch 'js/pthread-exit-emu-windows' (3978cd0)
   1Git 2.8 Release Notes
   2=====================
   3
   4Backward compatibility note
   5---------------------------
   6
   7The rsync:// transport has been removed.
   8
   9
  10Updates since v2.7
  11------------------
  12
  13UI, Workflows & Features
  14
  15 * It turns out "git clone" over rsync transport has been broken when
  16   the source repository has packed references for a long time, and
  17   nobody noticed nor complained about it.
  18
  19 * "branch --delete" has "branch -d" but "push --delete" does not.
  20
  21 * "git blame" learned to produce the progress eye-candy when it takes
  22   too much time before emitting the first line of the result.
  23
  24 * "git grep" can now be configured (or told from the command line)
  25   how many threads to use when searching in the working tree files.
  26
  27 * Some "git notes" operations, e.g. "git log --notes=<note>", should
  28   be able to read notes from any tree-ish that is shaped like a notes
  29   tree, but the notes infrastructure required that the argument must
  30   be a ref under refs/notes/.  Loosen it to require a valid ref only
  31   when the operation would update the notes (in which case we must
  32   have a place to store the updated notes tree, iow, a ref).
  33
  34 * "git grep" by default does not fall back to its "--no-index"
  35   behaviour outside a directory under Git's control (otherwise the
  36   user may by mistake end up running a huge recursive search); with a
  37   new configuration (set in $HOME/.gitconfig--by definition this
  38   cannot be set in the config file per project), this safety can be
  39   disabled.
  40
  41 * "git pull --rebase" has been extended to allow invoking
  42   "rebase -i".
  43
  44 * "git p4" learned to cope with the type of a file getting changed.
  45
  46 * "git format-patch" learned to notice format.outputDirectory
  47   configuration variable.  This allows "-o <dir>" option to be
  48   omitted on the command line if you always use the same directory in
  49   your workflow.
  50
  51 * "interpret-trailers" has been taught to optionally update a file in
  52   place, instead of always writing the result to the standard output.
  53
  54 * Many commands that read files that are expected to contain text
  55   that is generated (or can be edited) by the end user to control
  56   their behaviour (e.g. "git grep -f <filename>") have been updated
  57   to be more tolerant to lines that are terminated with CRLF (they
  58   used to treat such a line to contain payload that ends with CR,
  59   which is usually not what the users expect).
  60
  61 * "git notes merge" used to limit the source of the merged notes tree
  62   to somewhere under refs/notes/ hierarchy, which was too limiting
  63   when inventing a workflow to exchange notes with remote
  64   repositories using remote-tracking notes trees (located in e.g.
  65   refs/remote-notes/ or somesuch).
  66
  67 * "git ls-files" learned a new "--eol" option to help diagnose
  68   end-of-line problems.
  69
  70 * "ls-remote" learned an option to show which branch the remote
  71   repository advertises as its primary by pointing its HEAD at.
  72
  73 * New http.proxyAuthMethod configuration variable can be used to
  74   specify what authentication method to use, as a way to work around
  75   proxies that do not give error response expected by libcurl when
  76   CURLAUTH_ANY is used.  Also, the codepath for proxy authentication
  77   has been taught to use credential API to store the authentication
  78   material in user's keyrings.
  79
  80 * Update the untracked cache subsystem and change its primary UI from
  81   "git update-index" to "git config".
  82
  83 * There were a few "now I am doing this thing" progress messages in
  84   the TCP connection code that can be triggered by setting a verbose
  85   option internally in the code, but "git fetch -v" and friends never
  86   passed the verbose option down to that codepath.
  87
  88 * Clean/smudge filters defined in a configuration file of lower
  89   precedence can now be overridden to be a pass-through no-op by
  90   setting the variable to an empty string.
  91
  92 * A new "<branch>^{/!-<pattern>}" notation can be used to name a
  93   commit that is reachable from <branch> that does not match the
  94   given <pattern>.
  95
  96 * The "user.useConfigOnly" configuration variable can be used to
  97   force the user to always set user.email & user.name configuration
  98   variables, serving as a reminder for those who work on multiple
  99   projects and do not want to put these in their $HOME/.gitconfig.
 100
 101 * "git fetch" and friends that make network connections can now be
 102   told to only use ipv4 (or ipv6).
 103
 104 * Some authentication methods do not need username or password, but
 105   libcurl needs some hint that it needs to perform authentication.
 106   Supplying an empty username and password string is a valid way to
 107   do so, but you can set the http.[<url>.]emptyAuth configuration
 108   variable to achieve the same, if you find it cleaner.
 109
 110 * You can now set http.[<url>.]pinnedpubkey to specify the pinned
 111   public key when building with recent enough versions of libcURL.
 112
 113 * The configuration system has been taught to phrase where it found a
 114   bad configuration variable in a better way in its error messages.
 115   "git config" learnt a new "--show-origin" option to indicate where
 116   the values come from.
 117
 118 * The "credential-cache" daemon process used to run in whatever
 119   directory it happened to start in, but this made umount(2)ing the
 120   filesystem that houses the repository harder; now the process
 121   chdir()s to the directory that house its own socket on startup.
 122
 123 * When "git submodule update" did not result in fetching the commit
 124   object in the submodule that is referenced by the superproject, the
 125   command learned to retry another fetch, specifically asking for
 126   that commit that may not be connected to the refs it usually
 127   fetches.
 128
 129 * "git merge-recursive" learned "--no-renames" option to disable its
 130   rename detection logic.
 131
 132 * Across the transition at around Git version 2.0, the user used to
 133   get a pretty loud warning when running "git push" without setting
 134   push.default configuration variable.  We no longer warn, given that
 135   the transition is over long time ago.
 136
 137 * README has been renamed to README.md and its contents got tweaked
 138   slightly to make it easier on the eyes.
 139
 140
 141Performance, Internal Implementation, Development Support etc.
 142
 143 * Add a framework to spawn a group of processes in parallel, and use
 144   it to run "git fetch --recurse-submodules" in parallel.
 145
 146 * A slight update to the Makefile to mark "phoney" targets
 147   as such correctly.
 148
 149 * In-core storage of the reverse index for .pack files (which lets
 150   you go from a pack offset to an object name) has been streamlined.
 151
 152 * d95138e6 (setup: set env $GIT_WORK_TREE when work tree is set, like
 153   $GIT_DIR, 2015-06-26) attempted to work around a glitch in alias
 154   handling by overwriting GIT_WORK_TREE environment variable to
 155   affect subprocesses when set_git_work_tree() gets called, which
 156   resulted in a rather unpleasant regression to "clone" and "init".
 157   Try to address the same issue by always restoring the environment
 158   and respawning the real underlying command when handling alias.
 159
 160 * The low-level code that is used to create symbolic references has
 161   been updated to share more code with the code that deals with
 162   normal references.
 163
 164 * strbuf_getline() and friends have been redefined to make it easier
 165   to identify which callsite of (new) strbuf_getline_lf() should
 166   allow and silently ignore carriage-return at the end of the line to
 167   help users on DOSsy systems.
 168
 169 * "git shortlog" used to accumulate various pieces of information
 170   regardless of what was asked to be shown in the final output.  It
 171   has been optimized by noticing what need not to be collected
 172   (e.g. there is no need to collect the log messages when showing
 173   only the number of changes).
 174
 175 * "git checkout $branch" (and other operations that share the same
 176   underlying machinery) has been optimized.
 177
 178 * Automated tests in Travis CI environment has been optimized by
 179   persisting runtime statistics of previous "prove" run, executing
 180   tests that take longer before other ones; this reduces the total
 181   wallclock time.
 182
 183 * Test scripts have been updated to remove assumptions that are not
 184   portable between Git for POSIX and Git for Windows, or to skip ones
 185   with expectations that are not satisfiable on Git for Windows.
 186
 187 * Some calls to strcpy(3) triggers a false warning from static
 188   analysers that are less intelligent than humans, and reducing the
 189   number of these false hits helps us notice real issues.  A few
 190   calls to strcpy(3) in test-path-utils that are already safe has
 191   been rewritten to avoid false wanings.
 192
 193 * Some calls to strcpy(3) triggers a false warning from static
 194   analysers that are less intelligent than humans, and reducing the
 195   number of these false hits helps us notice real issues.  A few
 196   calls to strcpy(3) in "git rerere" that are already safe has been
 197   rewritten to avoid false wanings.
 198
 199 * The "name_path" API was an attempt to reduce the need to construct
 200   the full path out of a series of path components while walking a
 201   tree hierarchy, but over time made less efficient because the path
 202   needs to be flattened, e.g. to be compared with another path that
 203   is already flat.  The API has been removed and its users have been
 204   rewritten to simplify the overall code complexity.
 205
 206 * Help those who debug http(s) part of the system.
 207   (merge 0054045 sp/remote-curl-ssl-strerror later to maint).
 208
 209 * The internal API to interact with "remote.*" configuration
 210   variables has been streamlined.
 211
 212 * The ref-filter's format-parsing code has been refactored, in
 213   preparation for "branch --format" and friends.
 214
 215 * Traditionally, the tests that try commands that work on the
 216   contents in the working tree were named with "worktree" in their
 217   filenames, but with the recent addition of "git worktree"
 218   subcommand, whose tests are also named similarly, it has become
 219   harder to tell them apart.  The traditional tests have been renamed
 220   to use "work-tree" instead in an attempt to differentiate them.
 221   (merge 5549029 mg/work-tree-tests later to maint).
 222
 223 * Many codepaths forget to check return value from git_config_set();
 224   the function is made to die() to make sure we do not proceed when
 225   setting a configuration variable failed.
 226   (merge 3d18064 ps/config-error later to maint).
 227
 228 * Handling of errors while writing into our internal asynchronous
 229   process has been made more robust, which reduces flakiness in our
 230   tests.
 231   (merge 43f3afc jk/epipe-in-async later to maint).
 232
 233 * There is a new DEVELOPER knob that enables many compiler warning
 234   options in the Makefile.
 235
 236
 237Also contains various documentation updates and code clean-ups.
 238
 239
 240Fixes since v2.7
 241----------------
 242
 243Unless otherwise noted, all the fixes since v2.7 in the maintenance
 244track are contained in this release (see the maintenance releases'
 245notes for details).
 246
 247 * An earlier change in 2.5.x-era broke users' hooks and aliases by
 248   exporting GIT_WORK_TREE to point at the root of the working tree,
 249   interfering when they tried to use a different working tree without
 250   setting GIT_WORK_TREE environment themselves.
 251
 252 * The "exclude_list" structure has the usual "alloc, nr" pair of
 253   fields to be used by ALLOC_GROW(), but clear_exclude_list() forgot
 254   to reset 'alloc' to 0 when it cleared 'nr' to discard the managed
 255   array.
 256
 257 * Paths that have been told the index about with "add -N" are not
 258   quite yet in the index, but a few commands behaved as if they
 259   already are in a harmful way.
 260
 261 * "git send-email" was confused by escaped quotes stored in the alias
 262   files saved by "mutt", which has been corrected.
 263
 264 * A few unportable C construct have been spotted by clang compiler
 265   and have been fixed.
 266
 267 * The documentation has been updated to hint the connection between
 268   the '--signoff' option and DCO.
 269
 270 * "git reflog" incorrectly assumed that all objects that used to be
 271   at the tip of a ref must be commits, which caused it to segfault.
 272
 273 * The ignore mechanism saw a few regressions around untracked file
 274   listing and sparse checkout selection areas in 2.7.0; the change
 275   that is responsible for the regression has been reverted.
 276
 277 * Some codepaths used fopen(3) when opening a fixed path in $GIT_DIR
 278   (e.g. COMMIT_EDITMSG) that is meant to be left after the command is
 279   done.  This however did not work well if the repository is set to
 280   be shared with core.sharedRepository and the umask of the previous
 281   user is tighter.  They have been made to work better by calling
 282   unlink(2) and retrying after fopen(3) fails with EPERM.
 283
 284 * Asking gitweb for a nonexistent commit left a warning in the server
 285   log.
 286
 287   Somebody may want to follow this up with an additional test, perhaps?
 288   IIRC, we do test that no Perl warnings are given to the server log,
 289   so this should have been caught if our test coverage were good.
 290
 291 * "git rebase", unlike all other callers of "gc --auto", did not
 292   ignore the exit code from "gc --auto".
 293
 294 * Many codepaths that run "gc --auto" before exiting kept packfiles
 295   mapped and left the file descriptors to them open, which was not
 296   friendly to systems that cannot remove files that are open.  They
 297   now close the packs before doing so.
 298
 299 * A recent optimization to filter-branch in v2.7.0 introduced a
 300   regression when --prune-empty filter is used, which has been
 301   corrected.
 302
 303 * The description for SANITY prerequisite the test suite uses has
 304   been clarified both in the comment and in the implementation.
 305
 306 * "git tag" started listing a tag "foo" as "tags/foo" when a branch
 307   named "foo" exists in the same repository; remove this unnecessary
 308   disambiguation, which is a regression introduced in v2.7.0.
 309
 310 * The way "git svn" uses auth parameter was broken by Subversion
 311   1.9.0 and later.
 312
 313 * The "split" subcommand of "git subtree" (in contrib/) incorrectly
 314   skipped merges when it shouldn't, which was corrected.
 315
 316 * A few options of "git diff" did not work well when the command was
 317   run from a subdirectory.
 318
 319 * The command line completion learned a handful of additional options
 320   and command specific syntax.
 321
 322 * dirname() emulation has been added, as Msys2 lacks it.
 323
 324 * The underlying machinery used by "ls-files -o" and other commands
 325   have been taught not to create empty submodule ref cache for a
 326   directory that is not a submodule.  This removes a ton of wasted
 327   CPU cycles.
 328
 329 * "git worktree" had a broken code that attempted to auto-fix
 330   possible inconsistency that results from end-users moving a
 331   worktree to different places without telling Git (the original
 332   repository needs to maintain backpointers to its worktrees, but
 333   "mv" run by end-users who are not familiar with that fact will
 334   obviously not adjust them), which actually made things worse
 335   when triggered.
 336
 337 * The low-level merge machinery has been taught to use CRLF line
 338   termination when inserting conflict markers to merged contents that
 339   are themselves CRLF line-terminated.
 340
 341 * "git push --force-with-lease" has been taught to report if the push
 342   needed to force (or fast-forwarded).
 343
 344 * The emulated "yes" command used in our test scripts has been
 345   tweaked not to spend too much time generating unnecessary output
 346   that is not used, to help those who test on Windows where it would
 347   not stop until it fills the pipe buffer due to lack of SIGPIPE.
 348
 349 * The documentation for "git clean" has been corrected; it mentioned
 350   that .git/modules/* are removed by giving two "-f", which has never
 351   been the case.
 352
 353 * The vimdiff backend for "git mergetool" has been tweaked to arrange
 354   and number buffers in the order that would match the expectation of
 355   majority of people who read left to right, then top down and assign
 356   buffers 1 2 3 4 "mentally" to local base remote merge windows based
 357   on that order.
 358
 359 * "git show 'HEAD:Foo[BAR]Baz'" did not interpret the argument as a
 360   rev, i.e. the object named by the the pathname with wildcard
 361   characters in a tree object.
 362   (merge aac4fac nd/dwim-wildcards-as-pathspecs later to maint).
 363
 364 * "git rev-parse --git-common-dir" used in the worktree feature
 365   misbehaved when run from a subdirectory.
 366   (merge 17f1365 nd/git-common-dir-fix later to maint).
 367
 368 * Another try to add support to the ignore mechanism that lets you
 369   say "this is excluded" and then later say "oh, no, this part (that
 370   is a subset of the previous part) is not excluded".
 371
 372 * "git worktree add -B <branchname>" did not work.
 373
 374 * The "v(iew)" subcommand of the interactive "git am -i" command was
 375   broken in 2.6.0 timeframe when the command was rewritten in C.
 376   (merge 708b8cc jc/am-i-v-fix later to maint).
 377
 378 * "git merge-tree" used to mishandle "both sides added" conflict with
 379   its own "create a fake ancestor file that has the common parts of
 380   what both sides have added and do a 3-way merge" logic; this has
 381   been updated to use the usual "3-way merge with an empty blob as
 382   the fake common ancestor file" approach used in the rest of the
 383   system.
 384   (merge 907681e jk/no-diff-emit-common later to maint).
 385
 386 * The memory ownership rule of fill_textconv() API, which was a bit
 387   tricky, has been documented a bit better.
 388   (merge a64e6a4 jk/more-comments-on-textconv later to maint).
 389
 390 * Update various codepaths to avoid manually-counted malloc().
 391   (merge 08c95df jk/tighten-alloc later to maint).
 392
 393 * The documentation did not clearly state that the 'simple' mode is
 394   now the default for "git push" when push.default configuration is
 395   not set.
 396   (merge f6b1fb3 mm/push-simple-doc later to maint).
 397
 398 * Recent versions of GNU grep are pickier when their input contains
 399   arbitrary binary data, which some of our tests uses.  Rewrite the
 400   tests to sidestep the problem.
 401   (merge 3b1442d jk/grep-binary-workaround-in-test later to maint).
 402
 403 * A helper function "git submodule" uses since v2.7.0 to list the
 404   modules that match the pathspec argument given to its subcommands
 405   (e.g. "submodule add <repo> <path>") has been fixed.
 406   (merge 2b56bb7 sb/submodule-module-list-fix later to maint).
 407
 408 * "git config section.var value" to set a value in per-repository
 409   configuration file failed when it was run outside any repository,
 410   but didn't say the reason correctly.
 411   (merge 638fa62 js/config-set-in-non-repository later to maint).
 412
 413 * Other minor clean-ups and documentation updates
 414   (merge f459823 ak/extract-argv0-last-dir-sep later to maint).
 415   (merge 63ca1c0 ak/git-strip-extension-from-dashed-command later to maint).
 416   (merge 4867f11 ps/plug-xdl-merge-leak later to maint).
 417   (merge 4938686 dt/initial-ref-xn-commit-doc later to maint).
 418   (merge 9537f21 ma/update-hooks-sample-typofix later to maint).