<branch> can be omitted in this syntax, and it's actually documented a
few paragraphs down:

  You could omit <branch>, in which case the command degenerates to
  "check out the current branch", which is a glorified no-op with
  rather expensive side-effects to show only the tracking information,
  if exists, for the current branch.
Signed-off-by: NNguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

It's easier to search for and also less cryptic.
Signed-off-by: NNguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NJunio C Hamano <gitster@pobox.com>

* maint:
  mingw: allow building with an MSYS2 runtime v3.x

Docfix.

* js/rebase-recreate-merge:
  rebase docs: fix "gitlink" typo

Dev support.

* js/untravis-windows:
  travis: remove the hack to build the Windows job on Azure Pipelines

Doxfix.

* rd/gc-prune-doc-fix:
  docs/git-gc: fix typo "--prune=all" to "--prune=now"

The Makefile uses 'find' utility to enumerate all the *.h header
files, which is expensive on platforms with slow filesystems; it
now optionally uses "ls-files" if working within a repository,
which is a trick similar to how all sources are enumerated to run
ETAGS on.

* js/find-lib-h-with-ls-files-when-possible:
  Makefile: use `git ls-files` to list header files, if possible

The set of header files used by "make hdr-check" unconditionally
included sha256/gcrypt.h, even when it is not used, causing the
make target to fail.  We now skip it when GCRYPT_SHA256 is not in
use.

* rj/hdr-check-gcrypt-fix:
  Makefile: fix 'hdr-check' when GCRYPT not installed

The include file compat/bswap.h has been updated so that it is safe
to (accidentally) include it more than once.

* jk/guard-bswap-header:
  compat/bswap: add include header guards

In-code comment typofix.

* rd/attr.c-comment-typofix:
  attr.c: ".gitattribute" -> ".gitattributes" (comments)

Doc update.

* yb/utf-16le-bom-spellfix:
  gitattributes.txt: fix typo

Recently the Git for Windows project started the upgrade process to
a MSYS2 runtime version based on Cygwin v3.x.

This has the very notable consequence that `$(uname -r)` no longer
reports a version starting with "2", but a version with "3".

That breaks our build, as df5218b4 (config.mak.uname: support MSys2,
2016-01-13) simply did not expect the version reported by `uname -r` to
depend on the underlying Cygwin version: it expected the reported
version to match the "2" in "MSYS2".

So let's invert that test case to test for *anything else* than a
version starting with "1" (for MSys). That should safeguard us for the
future, even if Cygwin ends up releasing versionsl like 314.272.65536.
Signed-off-by: NJohannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

In 20d2a30f (Makefile: replace perl/Makefile.PL with simple make
rules, 2017-12-10), Git stopped using MakeMaker. Therefore, that
definition in the MINGW-specific section became useless.
Signed-off-by: NJohannes Schindelin <johannes.schindelin@gmx.de>
Reviewed-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Unify RPC code for smart http in protocol v0/v1 and v2, which fixes
a bug in the latter (lack of authentication retry) and generally
improves the code base.

* jt/http-auth-proto-v2-fix:
  remote-curl: use post_rpc() for protocol v2 also
  remote-curl: refactor reading into rpc_state's buf
  remote-curl: reduce scope of rpc_state.result
  remote-curl: reduce scope of rpc_state.stdin_preamble
  remote-curl: reduce scope of rpc_state.argv

"git diff --no-index" may still want to access Git goodies like
--ext-diff and --textconv, but so far these have been ignored,
which has been corrected.

* jk/diff-no-index-initialize:
  diff: reuse diff setup for --no-index case

Unused code removal.

* nd/no-more-check-racy:
  Delete check-racy.c

Doc update.

* rd/doc-hook-used-in-sample:
  mention use of "hooks.allownonascii" in "man githooks"

Second batch to teach the diff machinery to use the parse-options
API.

* nd/diff-parseopt-2: (21 commits)
  diff-parseopt: convert --ignore-some-changes
  diff-parseopt: convert --[no-]minimal
  diff-parseopt: convert --relative
  diff-parseopt: convert --no-renames|--[no--rename-empty
  diff-parseopt: convert --find-copies-harder
  diff-parseopt: convert -C|--find-copies
  diff-parseopt: convert -D|--irreversible-delete
  diff-parseopt: convert -M|--find-renames
  diff-parseopt: convert -B|--break-rewrites
  diff-parseopt: convert --output-*
  diff-parseopt: convert --[no-]compact-summary
  diff-parseopt: convert --stat*
  diff-parseopt: convert -s|--no-patch
  diff-parseopt: convert --name-status
  diff-parseopt: convert --name-only
  diff-parseopt: convert --patch-with-stat
  diff-parseopt: convert --summary
  diff-parseopt: convert --check
  diff-parseopt: convert --dirstat and friends
  diff-parseopt: convert --numstat and --shortstat
  ...

Doc update.

* en/merge-options-doc:
  merge-options.txt: correct wording of --no-commit option

The command line completion (in contrib/) has been taught to
complete more subcommand parameters.

* nd/completion-more-parameters:
  completion: add more parameter value completion

Memfix.

* ab/receive-pack-use-after-free-fix:
  receive-pack: fix use-after-free bug

Doc update.

* dl/doc-submodule-wo-subcommand:
  submodule: document default behavior

Code clean-up.

* jk/unused-params:
  ref-filter: drop unused "sz" parameters
  ref-filter: drop unused "obj" parameters
  ref-filter: drop unused buf/sz pairs
  files-backend: drop refs parameter from split_symref_update()
  pack-objects: drop unused parameter from oe_map_new_pack()
  merge-recursive: drop several unused parameters
  diff: drop complete_rewrite parameter from run_external_diff()
  diff: drop unused emit data parameter from sane_truncate_line()
  diff: drop unused color reset parameters
  diff: drop options parameter from diffcore_fix_diff_index()

"git prune" has been taught to take advantage of reachability
bitmap when able.

* jk/prune-optim:
  t5304: rename "sha1" variables to "oid"
  prune: check SEEN flag for reachability
  prune: use bitmaps for reachability traversal
  prune: lazily perform reachability traversal

A more structured way to obtain execution trace has been added.

* jh/trace2:
  trace2: add for_each macros to clang-format
  trace2: t/helper/test-trace2, t0210.sh, t0211.sh, t0212.sh
  trace2:data: add subverb for rebase
  trace2:data: add subverb to reset command
  trace2:data: add subverb to checkout command
  trace2:data: pack-objects: add trace2 regions
  trace2:data: add trace2 instrumentation to index read/write
  trace2:data: add trace2 hook classification
  trace2:data: add trace2 transport child classification
  trace2:data: add trace2 sub-process classification
  trace2:data: add editor/pager child classification
  trace2:data: add trace2 regions to wt-status
  trace2: collect Windows-specific process information
  trace2: create new combined trace facility
  trace2: Documentation/technical/api-trace2.txt

Doc update.

* js/doc-symref-in-proto-v1:
  protocol-capabilities.txt: document symref

Split-index fix.

* nd/split-index-null-base-fix:
  read-cache.c: fix writing "link" index ext with null base oid

"git prune-packed" did not notice and complain against excess
arguments given from the command line, which now it does.

* rj/prune-packed-excess-args:
  prune-packed: check for too many arguments

Test doc update.

* jc/test-yes-doc:
  test: caution on our version of 'yes'

Output from "diff --cc" did not show the original paths when the
merge involved renames.  A new option adds the paths in the
original trees to the output.

* en/combined-all-paths:
  log,diff-tree: add --combined-all-paths option

Update the implementation of pack-redundant for performance in a
repository with many packfiles.

* sc/pack-redundant:
  pack-redundant: consistent sort method
  pack-redundant: rename pack_list.all_objects
  pack-redundant: new algorithm to find min packs
  pack-redundant: delete redundant code
  pack-redundant: delay creation of unique_objects
  t5323: test cases for git-pack-redundant

"git branch" learned a new subcommand "--show-current".

* du/branch-show-current:
  branch: introduce --show-current display option

Command-line completion (in contrib/) learned to tab-complete the
"git submodule absorbgitdirs" subcommand.

* dl/complete-submodule-absorbgitdirs:
  completion: complete git submodule absorbgitdirs

Four new configuration variables {author,committer}.{name,email}
have been introduced to override user.{name,email} in more specific
cases.

* wh/author-committer-ident-config:
  config: allow giving separate author and committer idents

The %(trailers) formatter in "git log --format=..."  now allows to
optionally pick trailers selectively by keyword, show only values,
etc.

* aw/pretty-trailers:
  pretty: add support for separator option in %(trailers)
  strbuf: separate callback for strbuf_expand:ing literals
  pretty: add support for "valueonly" option in %(trailers)
  pretty: allow showing specific trailers
  pretty: single return path in %(trailers) handling
  pretty: allow %(trailers) options with explicit value
  doc: group pretty-format.txt placeholders descriptions

The diff machinery, one of the oldest parts of the system, which
long predates the parse-options API, uses fairly long and complex
handcrafted option parser.  This is being rewritten to use the
parse-options API.

* nd/diff-parseopt:
  diff.c: convert --raw
  diff.c: convert -W|--[no-]function-context
  diff.c: convert -U|--unified
  diff.c: convert -u|-p|--patch
  diff.c: prepare to use parse_options() for parsing
  diff.h: avoid bit fields in struct diff_flags
  diff.h: keep forward struct declarations sorted
  parse-options: allow ll_callback with OPTION_CALLBACK
  parse-options: avoid magic return codes
  parse-options: stop abusing 'callback' for lowlevel callbacks
  parse-options: add OPT_BITOP()
  parse-options: disable option abbreviation with PARSE_OPT_KEEP_UNKNOWN
  parse-options: add one-shot mode
  parse-options.h: remove extern on function prototypes

"git checkout --no-overlay" can be used to trigger a new mode of
checking out paths out of the tree-ish, that allows paths that
match the pathspec that are in the current index and working tree
and are not in the tree-ish.

* tg/checkout-no-overlay:
  revert "checkout: introduce checkout.overlayMode config"
  checkout: introduce checkout.overlayMode config
  checkout: introduce --{,no-}overlay option
  checkout: factor out mark_cache_entry_for_checkout function
  checkout: clarify comment
  read-cache: add invalidate parameter to remove_marked_cache_entries
  entry: support CE_WT_REMOVE flag in checkout_entry
  entry: factor out unlink_entry function
  move worktree tests to t24*

Correct misspelled ".gitattribute" in comments only, so no functional
change.
Signed-off-by: NRobert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>