Documentation / RelNotes / 2.2.0.txton commit Update draft release notes to 2.2 (19b5d50)
   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
  13UI, Workflows & Features
  14
  15 * "git archive" learned to filter what gets archived with pathspec.
  16
  17 * "git config --edit --global" starts from a skeletal per-user
  18   configuration file contents, instead of a total blank, when the
  19   user does not already have any.  This immediately reduces the
  20   need for a later "Have you forgotten setting core.user?" and we
  21   can add more to the template as we gain more experience.
  22
  23 * "git stash list -p" used to be almost always a no-op because each
  24   stash entry is represented as a merge commit.  It learned to show
  25   the difference between the base commit version and the working tree
  26   version, which is in line with what "git show" gives.
  27
  28 * Sometimes users want to report a bug they experience on their
  29   repository, but they are not at liberty to share the contents of
  30   the repository.  "fast-export" was taught an "--anonymize" option
  31   to replace blob contents, names of people and paths and log
  32   messages with bland and simple strings to help them.
  33
  34 * "log --date=iso" uses a slight variant of ISO 8601 format that is
  35   made more human readable.  A new "--date=iso-strict" option gives
  36   datetime output that is more strictly conformant.
  37
  38 * A broken reimplementation of Git could write an invalid index that
  39   records both stage #0 and higher stage entries for the same path.
  40   We now notice and reject such an index, as there is no sensible
  41   fallback (we do not know if the broken tool wanted to resolve and
  42   forgot to remove higher stage entries, or if it wanted to unresolve
  43   and forgot to remove the stage#0 entry).
  44
  45 * The temporary files "git mergetool" uses are named to avoid too
  46   many dots in them (e.g. a temporary file for "hello.c" used to be
  47   named e.g. "hello.BASE.4321.c" but now uses underscore instead,
  48   e.g. "hello_BASE_4321.c").
  49
  50 * The temporary files "git mergetools" uses can be placed in a newly
  51   creted temporary directory, instead of the current directory, by
  52   setting the mergetool.writeToTemp configuration variable.
  53
  54 * The "pre-receive" and "post-receive" hooks are no longer required
  55   to consume their input fully (not following this requirement used
  56   to result in intermittent errors in "git push").
  57
  58 * The pretty-format specifier "%d", which expanded to " (tagname)"
  59   for a tagged commit, gained a cousin "%D" that just gives the
  60   "tagname" without frills.
  61
  62 * "git push" learned "--signed" push, that allows a push (i.e.
  63   request to update the refs on the other side to point at a new
  64   history, together with the transmission of necessary objects) to be
  65   signed, so that it can be verified and audited, using the GPG
  66   signature of the person who pushed, that the tips of branches at a
  67   public repository really point the commits the pusher wanted to,
  68   without having to "trust" the server.
  69
  70 * "git interpret-trailers" is a new filter to programatically edit
  71    the tail end of the commit log messages.
  72
  73 * "git help everyday" shows the "Everyday Git in 20 commands or so"
  74   document, whose contents have been updated to more modern Git
  75   practice.
  76
  77
  78Performance, Internal Implementation, etc.
  79
  80 * The API to manipulate the "refs" has been restructured to make it
  81   more transactional, with the eventual goal to allow all-or-none
  82   atomic updates and migrating the storage to something other than
  83   the traditional filesystem based one (e.g. databases).
  84
  85 * The lockfile API and its users have been cleaned up.
  86
  87 * We no longer attempt to keep track of individual dependencies to
  88   the header files in the build procedure, relying on automated
  89   dependency generation support from modern compilers.
  90
  91 * In tests, we have been using NOT_{MINGW,CYGWIN} test prerequisites
  92   long before negated prerequisites e.g. !MINGW were invented.
  93   The former has been converted to the latter to avoid confusion.
  94
  95 * Looking up remotes configuration in a repository with very many
  96   remotes defined has been optimized.
  97
  98 * There are cases where you lock and open to write a file, close it
  99   to show the updated contents to external processes, and then have
 100   to update the file again while still holding the lock, but the
 101   lockfile API lacked support for such an access pattern.
 102
 103 * The API to allocate the structure to keep track of commit
 104   decoration has been updated to make it less cumbersome to use.
 105
 106 * An in-core caching layer to let us avoid reading the same
 107   configuration files number of times has been added.  A few commands
 108   have been converted to use this subsystem.
 109
 110 * Various code paths have been cleaned up and simplified by using
 111   "strbuf", "starts_with()", and "skip_prefix()" APIs more.
 112
 113 * A few codepaths that died when large blobs that would not fit in
 114   core are involved in their operation have been taught to punt
 115   instead, by e.g. marking too large a blob as not to be diffed.
 116
 117 * A few more code paths in "commit" and "checkout" have been taught
 118   to repopulate the cache-tree in the index, to help speed up later
 119   "write-tree" (used in "commit") and "diff-index --cached" (used in
 120   "status").
 121
 122 * A common programming mistake to assign the same short option name
 123   to two separate options is detected by parse_options() API to help
 124   developers.
 125
 126 * The code path to write out the packed-refs file has been optimized,
 127   which especially matters in a repository with a large number of
 128   refs.
 129
 130 * The check to see if a ref $F can be created by making sure no
 131   existing ref has $F/ as its prefix has been optimized, which
 132   especially matters in a repository with a large number of existing
 133   refs.
 134
 135 * "git fsck" was taught to check contents of tag objects a bit more.
 136
 137 * "git hash-object" was taught a "--literally" option to help
 138   debugging.
 139
 140 * When running a required clean filter, we do not have to mmap the
 141   original before feeding the filter.  Instead, stream the file
 142   contents directly to the filter and process its output.
 143
 144 * The scripts in the test suite can be run with "-x" option to show
 145   a shell-trace of each command run in them.
 146
 147
 148Also contains various documentation updates and code clean-ups.
 149
 150
 151Fixes since v2.1
 152----------------
 153
 154Unless otherwise noted, all the fixes since v2.1 in the maintenance
 155track are contained in this release (see the maintenance releases'
 156notes for details).
 157
 158 * "git log --pretty/format=" with an empty format string did not
 159   mean the more obvious "No output whatsoever" but "Use default
 160   format", which was counterintuitive.
 161
 162 * "git -c section.var command" and "git -c section.var= command"
 163   should pass the configuration differently (the former should be a
 164   boolean true, the latter should be an empty string).
 165
 166 * Applying a patch not generated by Git in a subdirectory used to
 167   check the whitespace breakage using the attributes for incorrect
 168   paths. Also whitespace checks were performed even for paths
 169   excluded via "git apply --exclude=<path>" mechanism.
 170
 171 * "git bundle create" with date-range specification were meant to
 172   exclude tags outside the range, but it didn't.
 173
 174 * "git add x" where x that used to be a directory has become a
 175   symbolic link to a directory misbehaved.
 176
 177 * The prompt script checked $GIT_DIR/ref/stash file to see if there
 178   is a stash, which was a no-no.
 179
 180 * Pack-protocol documentation had a minor typo.
 181
 182 * "git checkout -m" did not switch to another branch while carrying
 183   the local changes forward when a path was deleted from the index.
 184
 185 * "git daemon" (with NO_IPV6 build configuration) used to incorrectly
 186   use the hostname even when gethostbyname() reported that the given
 187   hostname is not found.
 188   (merge 107efbe rs/daemon-fixes later to maint).
 189
 190 * With sufficiently long refnames, "git fast-import" could have
 191   overflown an on-stack buffer.
 192
 193 * After "pack-refs --prune" packed refs at the top-level, it failed
 194   to prune them.
 195
 196 * Progress output from "git gc --auto" was visible in "git fetch -q".
 197
 198 * We used to pass -1000 to poll(2), expecting it to also mean "no
 199   timeout", which should be spelled as -1.
 200
 201 * "git rebase" documentation was unclear that it is required to
 202   specify on what <upstream> the rebase is to be done when telling it
 203   to first check out <branch>.
 204   (merge 95c6826 so/rebase-doc later to maint).
 205
 206 * "git push" over HTTP transport had an artificial limit on number of
 207   refs that can be pushed imposed by the command line length.
 208   (merge 26be19b jk/send-pack-many-refspecs later to maint).
 209
 210 * When receiving an invalid pack stream that records the same object
 211   twice, multiple threads got confused due to a race.
 212   (merge ab791dd jk/index-pack-threading-races later to maint).
 213
 214 * An attempt to remove the entire tree in the "git fast-import" input
 215   stream caused it to misbehave.
 216   (merge 2668d69 mb/fast-import-delete-root later to maint).
 217
 218 * Reachability check (used in "git prune" and friends) did not add a
 219   detached HEAD as a starting point to traverse objects still in use.
 220   (merge c40fdd0 mk/reachable-protect-detached-head later to maint).
 221
 222 * "git config --add section.var val" used to lose existing
 223   section.var whose value was an empty string.
 224   (merge c1063be ta/config-add-to-empty-or-true-fix later to maint).
 225
 226 * "git fsck" failed to report that it found corrupt objects via its
 227   exit status in some cases.
 228   (merge 30d1038 jk/fsck-exit-code-fix later to maint).
 229
 230 * Use of "--verbose" option used to break "git branch --merged".
 231   (merge 12994dd jk/maint-branch-verbose-merged later to maint).
 232
 233 * Some MUAs mangled a line in a message that begins with "From " to
 234   ">From " when writing to a mailbox file and feeding such an input
 235   to "git am" used to lose such a line.
 236   (merge 85de86a jk/mbox-from-line later to maint).
 237
 238 * "rev-parse --verify --quiet $name" is meant to quietly exit with a
 239   non-zero status when $name is not a valid object name, but still
 240   gave error messages in some cases.
 241
 242 * A handful of C source files have been updated to include
 243   "git-compat-util.h" as the first thing, to conform better to our
 244   coding guidelines.
 245   (merge 1c4b660 da/include-compat-util-first-in-c later to maint).
 246
 247 * t7004 test, which tried to run Git with small stack space, has been
 248   updated to give a bit larger stack to avoid false breakage on some
 249   platforms.
 250   (merge b9a1907 sk/tag-contains-wo-recursion later to maint).
 251
 252 * A few documentation pages had example sections marked up not quite
 253   correctly, which passed AsciiDoc but failed with AsciiDoctor.
 254   (merge c30c43c bc/asciidoc-pretty-formats-fix later to maint).
 255   (merge f8a48af bc/asciidoc later to maint).
 256
 257 * "gitweb" used deprecated CGI::startfrom, which was removed from
 258   CGI.pm as of 4.04; use CGI::start_from instead.
 259   (merge 4750f4b rm/gitweb-start-form later to maint).
 260
 261 * Newer versions of 'meld' breaks the auto-detection we use to see if
 262   they are new enough to support the `--output` option.
 263   (merge b12d045 da/mergetool-meld later to maint).