Documentation / RelNotes / 2.2.0.txton commit Merge branch 'for-junio' of git://bogomips.org/git-svn (ef59f32)
   1Git v2.2 Release Notes
   2======================
   3
   4Updates since v2.1
   5------------------
   6
   7Ports
   8
   9 * Building on older MacOS X systems automatically sets
  10   the necessary NO_APPLE_COMMON_CRYPTO build-time option.
  11
  12 * The support to build with NO_PTHREADS has been resurrected.
  13
  14 * Compilation options has been updated a bit to support z/OS port
  15   better.
  16
  17
  18UI, Workflows & Features
  19
  20 * "git archive" learned to filter what gets archived with pathspec.
  21
  22 * "git config --edit --global" starts from a skeletal per-user
  23   configuration file contents, instead of a total blank, when the
  24   user does not already have any.  This immediately reduces the
  25   need for a later "Have you forgotten setting core.user?" and we
  26   can add more to the template as we gain more experience.
  27
  28 * "git stash list -p" used to be almost always a no-op because each
  29   stash entry is represented as a merge commit.  It learned to show
  30   the difference between the base commit version and the working tree
  31   version, which is in line with what "git show" gives.
  32
  33 * Sometimes users want to report a bug they experience on their
  34   repository, but they are not at liberty to share the contents of
  35   the repository.  "fast-export" was taught an "--anonymize" option
  36   to replace blob contents, names of people and paths and log
  37   messages with bland and simple strings to help them.
  38
  39 * "git difftool" learned an option to stop feeding paths to the
  40   diff backend when it exits with a non-zero status.
  41
  42 * "log --date=iso" uses a slight variant of ISO 8601 format that is
  43   made more human readable.  A new "--date=iso-strict" option gives
  44   datetime output that is more strictly conformant.
  45
  46 * The logic "git prune" uses is more resilient against various corner
  47   cases.
  48
  49 * A broken reimplementation of Git could write an invalid index that
  50   records both stage #0 and higher stage entries for the same path.
  51   We now notice and reject such an index, as there is no sensible
  52   fallback (we do not know if the broken tool wanted to resolve and
  53   forgot to remove higher stage entries, or if it wanted to unresolve
  54   and forgot to remove the stage#0 entry).
  55
  56 * The temporary files "git mergetool" uses are named to avoid too
  57   many dots in them (e.g. a temporary file for "hello.c" used to be
  58   named e.g. "hello.BASE.4321.c" but now uses underscore instead,
  59   e.g. "hello_BASE_4321.c").
  60
  61 * The temporary files "git mergetools" uses can be placed in a newly
  62   creted temporary directory, instead of the current directory, by
  63   setting the mergetool.writeToTemp configuration variable.
  64
  65 * "git mergetool" understands "--tool bc" now, as version 4 of
  66   BeyondCompare can be driven the same way as its version 3 and it
  67   feels awkward to say "--tool bc3".
  68
  69 * The "pre-receive" and "post-receive" hooks are no longer required
  70   to consume their input fully (not following this requirement used
  71   to result in intermittent errors in "git push").
  72
  73 * The pretty-format specifier "%d", which expanded to " (tagname)"
  74   for a tagged commit, gained a cousin "%D" that just gives the
  75   "tagname" without frills.
  76
  77 * "git push" learned "--signed" push, that allows a push (i.e.
  78   request to update the refs on the other side to point at a new
  79   history, together with the transmission of necessary objects) to be
  80   signed, so that it can be verified and audited, using the GPG
  81   signature of the person who pushed, that the tips of branches at a
  82   public repository really point the commits the pusher wanted to,
  83   without having to "trust" the server.
  84
  85 * "git interpret-trailers" is a new filter to programatically edit
  86    the tail end of the commit log messages.
  87
  88 * "git help everyday" shows the "Everyday Git in 20 commands or so"
  89   document, whose contents have been updated to more modern Git
  90   practice.
  91
  92
  93Performance, Internal Implementation, etc.
  94
  95 * The API to manipulate the "refs" has been restructured to make it
  96   more transactional, with the eventual goal to allow all-or-none
  97   atomic updates and migrating the storage to something other than
  98   the traditional filesystem based one (e.g. databases).
  99
 100 * The lockfile API and its users have been cleaned up.
 101
 102 * We no longer attempt to keep track of individual dependencies to
 103   the header files in the build procedure, relying on automated
 104   dependency generation support from modern compilers.
 105
 106 * In tests, we have been using NOT_{MINGW,CYGWIN} test prerequisites
 107   long before negated prerequisites e.g. !MINGW were invented.
 108   The former has been converted to the latter to avoid confusion.
 109
 110 * Looking up remotes configuration in a repository with very many
 111   remotes defined has been optimized.
 112
 113 * There are cases where you lock and open to write a file, close it
 114   to show the updated contents to external processes, and then have
 115   to update the file again while still holding the lock, but the
 116   lockfile API lacked support for such an access pattern.
 117
 118 * The API to allocate the structure to keep track of commit
 119   decoration has been updated to make it less cumbersome to use.
 120
 121 * An in-core caching layer to let us avoid reading the same
 122   configuration files number of times has been added.  A few commands
 123   have been converted to use this subsystem.
 124
 125 * Various code paths have been cleaned up and simplified by using
 126   "strbuf", "starts_with()", and "skip_prefix()" APIs more.
 127
 128 * A few codepaths that died when large blobs that would not fit in
 129   core are involved in their operation have been taught to punt
 130   instead, by e.g. marking too large a blob as not to be diffed.
 131
 132 * A few more code paths in "commit" and "checkout" have been taught
 133   to repopulate the cache-tree in the index, to help speed up later
 134   "write-tree" (used in "commit") and "diff-index --cached" (used in
 135   "status").
 136
 137 * A common programming mistake to assign the same short option name
 138   to two separate options is detected by parse_options() API to help
 139   developers.
 140
 141 * The code path to write out the packed-refs file has been optimized,
 142   which especially matters in a repository with a large number of
 143   refs.
 144
 145 * The check to see if a ref $F can be created by making sure no
 146   existing ref has $F/ as its prefix has been optimized, which
 147   especially matters in a repository with a large number of existing
 148   refs.
 149
 150 * "git fsck" was taught to check contents of tag objects a bit more.
 151
 152 * "git hash-object" was taught a "--literally" option to help
 153   debugging.
 154
 155 * When running a required clean filter, we do not have to mmap the
 156   original before feeding the filter.  Instead, stream the file
 157   contents directly to the filter and process its output.
 158
 159 * The scripts in the test suite can be run with "-x" option to show
 160   a shell-trace of each command run in them.
 161
 162 * The "run-command" API learned to manage the argv and environment
 163   array for child process, alleviating the need for the callers to
 164   allocate and deallocate them.
 165
 166 * Some people use AsciiDoctor, instead of AsciiDoc, to format our
 167   documentation set; the documentation has been adjusted, as
 168   AsciiDoctor is pickier than AsciiDoc in its input mark-up.
 169
 170
 171Also contains various documentation updates and code clean-ups.
 172
 173
 174Fixes since v2.1
 175----------------
 176
 177Unless otherwise noted, all the fixes since v2.1 in the maintenance
 178track are contained in this release (see the maintenance releases'
 179notes for details).
 180
 181 * "git log --pretty/format=" with an empty format string did not
 182   mean the more obvious "No output whatsoever" but "Use default
 183   format", which was counterintuitive.
 184
 185 * "git -c section.var command" and "git -c section.var= command"
 186   should pass the configuration differently (the former should be a
 187   boolean true, the latter should be an empty string).
 188
 189 * Applying a patch not generated by Git in a subdirectory used to
 190   check the whitespace breakage using the attributes for incorrect
 191   paths. Also whitespace checks were performed even for paths
 192   excluded via "git apply --exclude=<path>" mechanism.
 193
 194 * "git bundle create" with date-range specification were meant to
 195   exclude tags outside the range, but it didn't.
 196
 197 * "git add x" where x that used to be a directory has become a
 198   symbolic link to a directory misbehaved.
 199
 200 * The prompt script checked $GIT_DIR/ref/stash file to see if there
 201   is a stash, which was a no-no.
 202
 203 * Pack-protocol documentation had a minor typo.
 204
 205 * "git checkout -m" did not switch to another branch while carrying
 206   the local changes forward when a path was deleted from the index.
 207
 208 * "git daemon" (with NO_IPV6 build configuration) used to incorrectly
 209   use the hostname even when gethostbyname() reported that the given
 210   hostname is not found.
 211   (merge 107efbe rs/daemon-fixes later to maint).
 212
 213 * With sufficiently long refnames, "git fast-import" could have
 214   overflown an on-stack buffer.
 215
 216 * After "pack-refs --prune" packed refs at the top-level, it failed
 217   to prune them.
 218
 219 * Progress output from "git gc --auto" was visible in "git fetch -q".
 220
 221 * We used to pass -1000 to poll(2), expecting it to also mean "no
 222   timeout", which should be spelled as -1.
 223
 224 * "git rebase" documentation was unclear that it is required to
 225   specify on what <upstream> the rebase is to be done when telling it
 226   to first check out <branch>.
 227   (merge 95c6826 so/rebase-doc later to maint).
 228
 229 * "git push" over HTTP transport had an artificial limit on number of
 230   refs that can be pushed imposed by the command line length.
 231   (merge 26be19b jk/send-pack-many-refspecs later to maint).
 232
 233 * When receiving an invalid pack stream that records the same object
 234   twice, multiple threads got confused due to a race.
 235   (merge ab791dd jk/index-pack-threading-races later to maint).
 236
 237 * An attempt to remove the entire tree in the "git fast-import" input
 238   stream caused it to misbehave.
 239   (merge 2668d69 mb/fast-import-delete-root later to maint).
 240
 241 * Reachability check (used in "git prune" and friends) did not add a
 242   detached HEAD as a starting point to traverse objects still in use.
 243   (merge c40fdd0 mk/reachable-protect-detached-head later to maint).
 244
 245 * "git config --add section.var val" used to lose existing
 246   section.var whose value was an empty string.
 247   (merge c1063be ta/config-add-to-empty-or-true-fix later to maint).
 248
 249 * "git fsck" failed to report that it found corrupt objects via its
 250   exit status in some cases.
 251   (merge 30d1038 jk/fsck-exit-code-fix later to maint).
 252
 253 * Use of "--verbose" option used to break "git branch --merged".
 254   (merge 12994dd jk/maint-branch-verbose-merged later to maint).
 255
 256 * Some MUAs mangled a line in a message that begins with "From " to
 257   ">From " when writing to a mailbox file and feeding such an input
 258   to "git am" used to lose such a line.
 259   (merge 85de86a jk/mbox-from-line later to maint).
 260
 261 * "rev-parse --verify --quiet $name" is meant to quietly exit with a
 262   non-zero status when $name is not a valid object name, but still
 263   gave error messages in some cases.
 264
 265 * A handful of C source files have been updated to include
 266   "git-compat-util.h" as the first thing, to conform better to our
 267   coding guidelines.
 268   (merge 1c4b660 da/include-compat-util-first-in-c later to maint).
 269
 270 * t7004 test, which tried to run Git with small stack space, has been
 271   updated to give a bit larger stack to avoid false breakage on some
 272   platforms.
 273   (merge b9a1907 sk/tag-contains-wo-recursion later to maint).
 274
 275 * A few documentation pages had example sections marked up not quite
 276   correctly, which passed AsciiDoc but failed with AsciiDoctor.
 277   (merge c30c43c bc/asciidoc-pretty-formats-fix later to maint).
 278   (merge f8a48af bc/asciidoc later to maint).
 279
 280 * "gitweb" used deprecated CGI::startfrom, which was removed from
 281   CGI.pm as of 4.04; use CGI::start_from instead.
 282   (merge 4750f4b rm/gitweb-start-form later to maint).
 283
 284 * Newer versions of 'meld' breaks the auto-detection we use to see if
 285   they are new enough to support the `--output` option.
 286   (merge b12d045 da/mergetool-meld later to maint).
 287
 288 * "git pack-objects" forgot to disable the codepath to generate
 289   object recheability bitmap when it needs to split the resulting
 290   pack.
 291   (merge 2113471 jk/pack-objects-no-bitmap-when-splitting later to maint).