Documentation / RelNotes / 2.22.0.txton commit Git 2.22-rc0 (ab15ad1)
   1Git 2.22 Release Notes
   2======================
   3
   4Updates since v2.21
   5-------------------
   6
   7UI, Workflows & Features
   8
   9 * "git checkout --no-overlay" can be used to trigger a new mode of
  10   checking out paths out of the tree-ish, that allows paths that
  11   match the pathspec that are in the current index and working tree
  12   and are not in the tree-ish.
  13
  14 * The %(trailers) formatter in "git log --format=..."  now allows to
  15   optionally pick trailers selectively by keyword, show only values,
  16   etc.
  17
  18 * Four new configuration variables {author,committer}.{name,email}
  19   have been introduced to override user.{name,email} in more specific
  20   cases.
  21
  22 * Command-line completion (in contrib/) learned to tab-complete the
  23   "git submodule absorbgitdirs" subcommand.
  24
  25 * "git branch" learned a new subcommand "--show-current".
  26
  27 * Output from "diff --cc" did not show the original paths when the
  28   merge involved renames.  A new option adds the paths in the
  29   original trees to the output.
  30
  31 * The command line completion (in contrib/) has been taught to
  32   complete more subcommand parameters.
  33
  34 * The final report from "git bisect" used to show the suspected
  35   culprit using a raw "diff-tree", with which there is no output for
  36   a merge commit.  This has been updated to use a more modern and
  37   human readable output that still is concise enough.
  38
  39 * "git rebase --rebase-merges" replaces its old "--preserve-merges"
  40   option; the latter is now marked as deprecated.
  41
  42 * Error message given while cloning with --recurse-submodules has
  43   been updated.
  44
  45 * The completion helper code now pays attention to repository-local
  46   configuration (when available), which allows --list-cmds to honour
  47   a repository specific setting of completion.commands, for example.
  48
  49 * "git mergetool" learned to offer Sublime Merge (smerge) as one of
  50   its backends.
  51
  52 * A new hook "post-index-change" is called when the on-disk index
  53   file changes, which can help e.g. a virtualized working tree
  54   implementation.
  55
  56 * "git difftool" can now run outside a repository.
  57
  58 * "git checkout -m <other>" was about carrying the differences
  59   between HEAD and the working-tree files forward while checking out
  60   another branch, and ignored the differences between HEAD and the
  61   index.  The command has been taught to abort when the index and the
  62   HEAD are different.
  63
  64 * A progress indicator has been added to the "index-pack" step, which
  65   often makes users wait for completion during "git clone".
  66
  67 * "git submodule" learns "set-branch" subcommand that allows the
  68   submodule.*.branch settings to be modified.
  69
  70 * "git merge-recursive" backend recently learned a new heuristics to
  71   infer file movement based on how other files in the same directory
  72   moved.  As this is inherently less robust heuristics than the one
  73   based on the content similarity of the file itself (rather than
  74   based on what its neighbours are doing), it sometimes gives an
  75   outcome unexpected by the end users.  This has been toned down to
  76   leave the renamed paths in higher/conflicted stages in the index so
  77   that the user can examine and confirm the result.
  78
  79 * "git tag" learned to give an advice suggesting it might be a
  80   mistake when creating an annotated or signed tag that points at
  81   another tag.
  82
  83 * The "git pack-objects" command learned to report the number of
  84   objects it packed via the trace2 mechanism.
  85
  86 * The list of conflicted paths shown in the editor while concluding a
  87   conflicted merge was shown above the scissors line when the
  88   clean-up mode is set to "scissors", even though it was commented
  89   out just like the list of updated paths and other information to
  90   help the user explain the merge better.
  91
  92 * The trace2 tracing facility learned to auto-generate a filename
  93   when told to log to a directory.
  94
  95 * "git clone" learned a new --server-option option when talking over
  96   the protocol version 2.
  97
  98 * The connectivity bitmaps are created by default in bare
  99   repositories now; also the pathname hash-cache is created by
 100   default to avoid making crappy deltas when repacking.
 101
 102
 103Performance, Internal Implementation, Development Support etc.
 104
 105 * The diff machinery, one of the oldest parts of the system, which
 106   long predates the parse-options API, uses fairly long and complex
 107   handcrafted option parser.  This is being rewritten to use the
 108   parse-options API.
 109
 110 * The implementation of pack-redundant has been updated for
 111   performance in a repository with many packfiles.
 112
 113 * A more structured way to obtain execution trace has been added.
 114
 115 * "git prune" has been taught to take advantage of reachability
 116   bitmap when able.
 117
 118 * The command line parser of "git commit-tree" has been rewritten to
 119   use the parse-options API.
 120
 121 * Suggest GitGitGadget instead of submitGit as a way to submit
 122   patches based on GitHub PR to us.
 123
 124 * The test framework has been updated to help developers by making it
 125   easier to run most of the tests under different versions of
 126   over-the-wire protocols.
 127
 128 * Dev support update to make it easier to compare two formatted
 129   results from our documentation.
 130
 131 * The scripted "git rebase" implementation has been retired.
 132
 133 * "git multi-pack-index verify" did not scale well with the number of
 134   packfiles, which is being improved.
 135
 136 * "git stash" has been rewritten in C.
 137
 138 * The "check-docs" Makefile target to support developers has been
 139   updated.
 140
 141 * The tests have been updated not to rely on the abbreviated option
 142   names the parse-options API offers, to protect us from an
 143   abbreviated form of an option that used to be unique within the
 144   command getting non-unique when a new option that share the same
 145   prefix is added.
 146
 147 * The scripted version of "git rebase -i" wrote and rewrote the todo
 148   list many times during a single step of its operation, and the
 149   recent C-rewrite made a faithful conversion of the logic to C.  The
 150   implementation has been updated to carry necessary information
 151   around in-core to avoid rewriting the same file over and over
 152   unnecessarily.
 153
 154 * Test framework update to more robustly clean up leftover files and
 155   processes after tests are done.
 156
 157 * Conversion from unsigned char[20] to struct object_id continues.
 158
 159 * While running "git diff" in a lazy clone, we can upfront know which
 160   missing blobs we will need, instead of waiting for the on-demand
 161   machinery to discover them one by one.  The code learned to aim to
 162   achieve better performance by batching the request for these
 163   promised blobs.
 164
 165 * During an initial "git clone --depth=..." partial clone, it is
 166   pointless to spend cycles for a large portion of the connectivity
 167   check that enumerates and skips promisor objects (which by
 168   definition is all objects fetched from the other side).  This has
 169   been optimized out.
 170
 171 * Mechanically and systematically drop "extern" from function
 172   declarlation.
 173
 174 * The script to aggregate perf result unconditionally depended on
 175   libjson-perl even though it did not have to, which has been
 176   corrected.
 177
 178 * The internal implementation of "git rebase -i" has been updated to
 179   avoid forking a separate "rebase--interactive" process.
 180
 181
 182Fixes since v2.21
 183-----------------
 184
 185 * "git prune-packed" did not notice and complain against excess
 186   arguments given from the command line, which now it does.
 187   (merge 9b0bd87ed2 rj/prune-packed-excess-args later to maint).
 188
 189 * Split-index fix.
 190   (merge 6e37c8ed3c nd/split-index-null-base-fix later to maint).
 191
 192 * "git diff --no-index" may still want to access Git goodies like
 193   --ext-diff and --textconv, but so far these have been ignored,
 194   which has been corrected.
 195   (merge 287ab28bfa jk/diff-no-index-initialize later to maint).
 196
 197 * Unify RPC code for smart http in protocol v0/v1 and v2, which fixes
 198   a bug in the latter (lack of authentication retry) and generally
 199   improves the code base.
 200   (merge a97d00799a jt/http-auth-proto-v2-fix later to maint).
 201
 202 * The include file compat/bswap.h has been updated so that it is safe
 203   to (accidentally) include it more than once.
 204   (merge 33aa579a55 jk/guard-bswap-header later to maint).
 205
 206 * The set of header files used by "make hdr-check" unconditionally
 207   included sha256/gcrypt.h, even when it is not used, causing the
 208   make target to fail.  We now skip it when GCRYPT_SHA256 is not in
 209   use.
 210   (merge f23aa18e7f rj/hdr-check-gcrypt-fix later to maint).
 211
 212 * The Makefile uses 'find' utility to enumerate all the *.h header
 213   files, which is expensive on platforms with slow filesystems; it
 214   now optionally uses "ls-files" if working within a repository,
 215   which is a trick similar to how all sources are enumerated to run
 216   ETAGS on.
 217   (merge 92b88eba9f js/find-lib-h-with-ls-files-when-possible later to maint).
 218
 219 * "git rebase" that was reimplemented in C did not set ORIG_HEAD
 220   correctly, which has been corrected.
 221   (merge cbd29ead92 js/rebase-orig-head-fix later to maint).
 222
 223 * Dev support.
 224   (merge f545737144 js/stress-test-ui-tweak later to maint).
 225
 226 * CFLAGS now can be tweaked when invoking Make while using
 227   DEVELOPER=YesPlease; this did not work well before.
 228   (merge 6d5d4b4e93 ab/makefile-help-devs-more later to maint).
 229
 230 * "git fsck --connectivity-only" omits computation necessary to sift
 231   the objects that are not reachable from any of the refs into
 232   unreachable and dangling.  This is now enabled when dangling
 233   objects are requested (which is done by default, but can be
 234   overridden with the "--no-dangling" option).
 235   (merge 8d8c2a5aef jk/fsck-doc later to maint).
 236
 237 * On platforms where "git fetch" is killed with SIGPIPE (e.g. OSX),
 238   the upload-pack that runs on the other end that hangs up after
 239   detecting an error could cause "git fetch" to die with a signal,
 240   which led to a flakey test.  "git fetch" now ignores SIGPIPE during
 241   the network portion of its operation (this is not a problem as we
 242   check the return status from our write(2)s).
 243   (merge 143588949c jk/no-sigpipe-during-network-transport later to maint).
 244
 245 * A recent update broke "is this object available to us?" check for
 246   well-known objects like an empty tree (which should yield "yes",
 247   even when there is no on-disk object for an empty tree), which has
 248   been corrected.
 249   (merge f06ab027ef jk/virtual-objects-do-exist later to maint).
 250
 251 * The setup code has been cleaned up to avoid leaks around the
 252   repository_format structure.
 253   (merge e8805af1c3 ma/clear-repository-format later to maint).
 254
 255 * "git config --type=color ..." is meant to replace "git config --get-color"
 256   but there is a slight difference that wasn't documented, which is
 257   now fixed.
 258   (merge cd8e7593b9 jk/config-type-color-ends-with-lf later to maint).
 259
 260 * When the "clean" filter can reduce the size of a huge file in the
 261   working tree down to a small "token" (a la Git LFS), there is no
 262   point in allocating a huge scratch area upfront, but the buffer is
 263   sized based on the original file size.  The convert mechanism now
 264   allocates very minimum and reallocates as it receives the output
 265   from the clean filter process.
 266   (merge 02156ab031 jh/resize-convert-scratch-buffer later to maint).
 267
 268 * "git rebase" uses the refs/rewritten/ hierarchy to store its
 269   intermediate states, which inherently makes the hierarchy per
 270   worktree, but it didn't quite work well.
 271   (merge b9317d55a3 nd/rewritten-ref-is-per-worktree later to maint).
 272
 273 * "git log -L<from>,<to>:<path>" with "-s" did not suppress the patch
 274   output as it should.  This has been corrected.
 275   (merge 05314efaea jk/line-log-with-patch later to maint).
 276
 277 * "git worktree add" used to do a "find an available name with stat
 278   and then mkdir", which is race-prone.  This has been fixed by using
 279   mkdir and reacting to EEXIST in a loop.
 280   (merge 7af01f2367 ms/worktree-add-atomic-mkdir later to maint).
 281
 282 * Build update for SHA-1 with collision detection.
 283   (merge 07a20f569b jk/sha1dc later to maint).
 284
 285 * Build procedure has been fixed around use of asciidoctor instead of
 286   asciidoc.
 287   (merge 185f9a0ea0 ma/asciidoctor-fixes later to maint).
 288
 289 * remote-http transport did not anonymize URLs reported in its error
 290   messages at places.
 291   (merge c1284b21f2 js/anonymize-remote-curl-diag later to maint).
 292
 293 * Error messages given from the http transport have been updated so
 294   that they can be localized.
 295   (merge ed8b4132c8 js/remote-curl-i18n later to maint).
 296
 297 * "git init" forgot to read platform-specific repository
 298   configuration, which made Windows port to ignore settings of
 299   core.hidedotfiles, for example.
 300
 301 * A corner-case object name ambiguity while the sequencer machinery
 302   is working (e.g. "rebase -i -x") has been fixed.
 303
 304 * "git format-patch" did not diagnose an error while opening the
 305   output file for the cover-letter, which has been corrected.
 306   (merge 2fe95f494c jc/format-patch-error-check later to maint).
 307
 308 * "git checkout -f <branch>" while the index has an unmerged path
 309   incorrectly left some paths in an unmerged state, which has been
 310   corrected.
 311
 312 * A corner case bug in the refs API has been corrected.
 313   (merge d3322eb28b jk/refs-double-abort later to maint).
 314
 315 * Unicode update.
 316   (merge 584b62c37b bb/unicode-12 later to maint).
 317
 318 * dumb-http walker has been updated to share more error recovery
 319   strategy with the normal codepath.
 320
 321 * A buglet in configuration parser has been fixed.
 322   (merge 19e7fdaa58 nd/include-if-wildmatch later to maint).
 323
 324 * The documentation for "git read-tree --reset -u" has been updated.
 325   (merge b5a0bd694c nd/read-tree-reset-doc later to maint).
 326
 327 * Code clean-up around a much-less-important-than-it-used-to-be
 328   update_server_info() funtion.
 329   (merge b3223761c8 jk/server-info-rabbit-hole later to maint).
 330
 331 * The message given when "git commit -a <paths>" errors out has been
 332   updated.
 333   (merge 5a1dbd48bc nd/commit-a-with-paths-msg-update later to maint).
 334
 335 * "git cherry-pick --options A..B", after giving control back to the
 336   user to ask help resolving a conflicted step, did not honor the
 337   options it originally received, which has been corrected.
 338
 339 * Various glitches in "git gc" around reflog handling have been fixed.
 340
 341 * The code to read from commit-graph file has been cleanup with more
 342   careful error checking before using data read from it.
 343
 344 * Performance fix around "git fetch" that grabs many refs.
 345   (merge b764300912 jt/fetch-pack-wanted-refs-optim later to maint).
 346
 347 * Protocol v2 support in "git fetch-pack" of shallow clones has been
 348   corrected.
 349
 350 * Performance fix around "git blame", especially in a linear history
 351   (which is the norm we should optimize for).
 352   (merge f892014943 dk/blame-keep-origin-blob later to maint).
 353
 354 * Performance fix for "rev-list --parents -- pathspec".
 355   (merge 8320b1dbe7 jk/revision-rewritten-parents-in-prio-queue later to maint).
 356
 357 * Updating the display with progress message has been cleaned up to
 358   deal better with overlong messages.
 359   (merge 545dc345eb sg/overlong-progress-fix later to maint).
 360
 361 * "git blame -- path" in a non-bare repository starts blaming from
 362   the working tree, and the same command in a bare repository errors
 363   out because there is no working tree by definition.  The command
 364   has been taught to instead start blaming from the commit at HEAD,
 365   which is more useful.
 366   (merge a544fb08f8 sg/blame-in-bare-start-at-head later to maint).
 367
 368 * An underallocation in the code to read the untracked cache
 369   extension has been corrected.
 370   (merge 3a7b45a623 js/untracked-cache-allocfix later to maint).
 371
 372 * The code is updated to check the result of memory allocation before
 373   it is used in more places, by using xmalloc and/or xcalloc calls.
 374   (merge 999b951b28 jk/xmalloc later to maint).
 375
 376 * The GETTEXT_POISON test option has been quite broken ever since it
 377   was made runtime-tunable, which has been fixed.
 378   (merge f88b9cb603 jc/gettext-test-fix later to maint).
 379
 380 * Test fix on APFS that is incapable of store paths in Latin-1.
 381   (merge 3889149619 js/iso8895-test-on-apfs later to maint).
 382
 383 * "git submodule foreach <command> --quiet" did not pass the option
 384   down correctly, which has been corrected.
 385   (merge a282f5a906 nd/submodule-foreach-quiet later to maint).
 386
 387 * "git send-email" has been taught to use quoted-printable when the
 388   payload contains carriage-return.  The use of the mechanism is in
 389   line with the design originally added the codepath that chooses QP
 390   when the payload has overly long lines.
 391   (merge 74d76a1701 bc/send-email-qp-cr later to maint).
 392
 393 * The recently added feature to add addresses that are on
 394   anything-by: trailers in 'git send-email' was found to be way too
 395   eager and considered nonsense strings as if they can be legitimate
 396   beginning of *-by: trailer.  This has been tightened.
 397
 398 * Builds with gettext broke on recent macOS w/ Homebrew, which
 399   seems to have stopped including from /usr/local/include; this
 400   has been corrected.
 401   (merge 92a1377a2a js/macos-gettext-build later to maint).
 402
 403 * Running "git add" on a repository created inside the current
 404   repository is an explicit indication that the user wants to add it
 405   as a submodule, but when the HEAD of the inner repository is on an
 406   unborn branch, it cannot be added as a submodule.  Worse, the files
 407   in its working tree can be added as if they are a part of the outer
 408   repository, which is not what the user wants.  These problems are
 409   being addressed.
 410   (merge f937bc2f86 km/empty-repo-is-still-a-repo later to maint).
 411
 412 * "git cherry-pick" run with the "-x" or the "--signoff" option used
 413   to (and more importantly, ought to) clean up the commit log message
 414   with the --cleanup=space option by default, but this has been
 415   broken since late 2017.  This has been fixed.
 416
 417 * When given a tag that points at a commit-ish, "git replace --graft"
 418   failed to peel the tag before writing a replace ref, which did not
 419   make sense because the old graft mechanism the feature wants to
 420   mimick only allowed to replace one commit object with another.
 421   This has been fixed.
 422   (merge ee521ec4cb cc/replace-graft-peel-tags later to maint).
 423
 424 * Code tightening against a "wrong" object appearing where an object
 425   of a different type is expected, instead of blindly assuming that
 426   the connection between objects are correctly made.
 427   (merge 97dd512af7 tb/unexpected later to maint).
 428
 429 * An earlier update for MinGW and Cygwin accidentally broke MSVC build,
 430   which has been fixed.
 431   (merge 22c3634c0f ss/msvc-path-utils-fix later to maint).
 432
 433 * %(push:track) token used in the --format option to "git
 434   for-each-ref" and friends was not showing the right branch, which
 435   has been fixed.
 436   (merge c646d0934e dr/ref-filter-push-track-fix later to maint).
 437
 438 * "make check-docs", "git help -a", etc. did not account for cases
 439   where a particular build may deliberately omit some subcommands,
 440   which has been corrected.
 441
 442 * The logic to tell if a Git repository has a working tree protects
 443   "git branch -D" from removing the branch that is currently checked
 444   out by mistake.  The implementation of this logic was broken for
 445   repositories with unusual name, which unfortunately is the norm for
 446   submodules these days.  This has been fixed.
 447   (merge f3534c98e4 jt/submodule-repo-is-with-worktree later to maint).
 448
 449 * AIX shared the same build issues with other BSDs around fileno(fp),
 450   which has been corrected.
 451   (merge ee662bf5c6 cc/aix-has-fileno-as-a-macro later to maint).
 452
 453 * The autoconf generated configure script failed to use the right
 454   gettext() implementations from -libintl by ignoring useless stub
 455   implementations shipped in some C library, which has been
 456   corrected.
 457   (merge b71e56a683 vk/autoconf-gettext later to maint).
 458
 459 * Fix index-pack perf test so that the repeated invocations always
 460   run in an empty repository, which emulates the initial clone
 461   situation better.
 462   (merge 775c71e16d jk/p5302-avoid-collision-check-cost later to maint).
 463
 464 * A "ls-files" that emulates "find" to enumerate files in the working
 465   tree resulted in duplicated Makefile rules that caused the build to
 466   issue an unnecessary warning during a trial build after merge
 467   conflicts are resolved in working tree *.h files but before the
 468   resolved results are added to the index.  This has been corrected.
 469
 470 * "git chery-pick" (and "revert" that shares the same runtime engine)
 471   that deals with multiple commits got confused when the final step
 472   gets stopped with a conflict and the user concluded the sequence
 473   with "git commit".  Attempt to fix it by cleaning up the state
 474   files used by these commands in such a situation.
 475   (merge 4a72486de9 pw/clean-sequencer-state-upon-final-commit later to maint).
 476
 477 * Code cleanup, docfix, build fix, etc.
 478   (merge 11f470aee7 jc/test-yes-doc later to maint).
 479   (merge 90503a240b js/doc-symref-in-proto-v1 later to maint).
 480   (merge 5c326d1252 jk/unused-params later to maint).
 481   (merge 68cabbfda3 dl/doc-submodule-wo-subcommand later to maint).
 482   (merge 9903623761 ab/receive-pack-use-after-free-fix later to maint).
 483   (merge 1ede45e44b en/merge-options-doc later to maint).
 484   (merge 3e14dd2c8e rd/doc-hook-used-in-sample later to maint).
 485   (merge c271dc28fd nd/no-more-check-racy later to maint).
 486   (merge e6e15194a8 yb/utf-16le-bom-spellfix later to maint).
 487   (merge bb101aaf0c rd/attr.c-comment-typofix later to maint).
 488   (merge 716a5af812 rd/gc-prune-doc-fix later to maint).
 489   (merge 50b206371d js/untravis-windows later to maint).
 490   (merge dbf47215e3 js/rebase-recreate-merge later to maint).
 491   (merge 56cb2d30f8 dl/reset-doc-no-wrt-abbrev later to maint).
 492   (merge 64eca306a2 ja/dir-rename-doc-markup-fix later to maint).
 493   (merge af91b0230c dl/ignore-docs later to maint).
 494   (merge 59a06e947b ra/t3600-test-path-funcs later to maint).
 495   (merge e041d0781b ar/t4150-remove-cruft later to maint).
 496   (merge 8d75a1d183 ma/asciidoctor-fixes-more later to maint).
 497   (merge 74cc547b0f mh/pack-protocol-doc-fix later to maint).
 498   (merge ed31851fa6 ab/doc-misc-typofixes later to maint).
 499   (merge a7256debd4 nd/checkout-m-doc-update later to maint).
 500   (merge 3a9e1ad78d jt/t5551-protocol-v2-does-not-have-half-auth later to maint).
 501   (merge 0b918b75af sg/t5318-cleanup later to maint).
 502   (merge 68ed71b53c cb/doco-mono later to maint).
 503   (merge a34dca2451 nd/interpret-trailers-docfix later to maint).
 504   (merge cf7b857a77 en/fast-import-parsing-fix later to maint).
 505   (merge fe61ccbc35 po/rerere-doc-fmt later to maint).
 506   (merge ffea0248bf po/describe-not-necessarily-7 later to maint).
 507   (merge 7cb7283adb tg/ls-files-debug-format-fix later to maint).
 508   (merge f64a21bd82 tz/doc-apostrophe-no-longer-needed later to maint).
 509   (merge dbe7b41019 js/t3301-unbreak-notes-test later to maint).
 510   (merge d8083e4180 km/t3000-retitle later to maint).
 511   (merge 9e4cbccbd7 tz/git-svn-doc-markup-fix later to maint).
 512   (merge da9ca955a7 jk/ls-files-doc-markup-fix later to maint).