t1509 test that requires a dedicated VM environment had some
bitrot, which has been corrected.

* ps/t1509-chroot-test-fixup:
  tests: fix cleanup after tests in t1509-root-worktree
  tests: fix broken && chains in t1509-root-worktree

* sb/check-return-from-read-ref:
  transport-helper: die on errors reading refs.

"git pull" in recent releases of Git has a regression in the code
that allows custom path to the --upload-pack=<program>.  This has
been corrected.

Note that this is irrelevant for 'master' with "git pull" rewritten
in C.

* mm/pull-upload-pack:
  pull.sh: quote $upload_pack when passing it to git-fetch

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

Allow untracked cache (experimental) to be used when sparse
checkout (experimental) is also in use.

* dt/untracked-sparse:
  untracked-cache: support sparse checkout

* ta/docfix-index-format-tech:
  typofix for index-format.txt

An off-by-one error made "git remote" to mishandle a remote with a
single letter nickname.

* mh/get-remote-group-fix:
  get_remote_group(): use skip_prefix()
  get_remote_group(): eliminate superfluous call to strcspn()
  get_remote_group(): rename local variable "space" to "wordlen"
  get_remote_group(): handle remotes with single-character names

"git pull --rebase" has been taught to pay attention to
rebase.autostash configuration.

* kd/pull-rebase-autostash:
  pull: allow dirty tree when rebase.autostash enabled

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

* sb/remove-unused-var-from-builtin-add:
  add: remove dead code

* sb/parse-options-codeformat:
  parse-options: align curly braces for all options

The code to perform multi-tree merges has been taught to repopulate
the cache-tree upon a successful merge into the index, so that
subsequent "diff-index --cached" (hence "status") and "write-tree"
(hence "commit") will go faster.

The same logic in "git checkout" may now be removed, but that is a
separate issue.

* dt/unpack-trees-cache-tree-revalidate:
  unpack-trees: populate cache-tree on successful merge

Tests that assume how reflogs are represented on the filesystem too
much have been corrected.

* dt/reflog-tests:
  tests: remove some direct access to .git/logs
  t/t7509: remove unnecessary manipulation of reflog

The "new-worktree-mode" hack in "checkout" that was added in
nd/multiple-work-trees topic has been removed by updating the
implementation of new "worktree add".

* es/worktree-add-cleanup: (25 commits)
  Documentation/git-worktree: fix duplicated 'from'
  Documentation/config: mention "now" and "never" for 'expire' settings
  Documentation/git-worktree: fix broken 'linkgit' invocation
  checkout: drop intimate knowledge of newly created worktree
  worktree: populate via "git reset --hard" rather than "git checkout"
  worktree: avoid resolving HEAD unnecessarily
  worktree: make setup of new HEAD distinct from worktree population
  worktree: detect branch-name/detached and error conditions locally
  worktree: add_worktree: construct worktree-population command locally
  worktree: elucidate environment variables intended for child processes
  worktree: make branch creation distinct from worktree population
  worktree: add: suppress auto-vivication with --detach and no <branch>
  worktree: make --detach mutually exclusive with -b/-B
  worktree: introduce options container
  worktree: simplify new branch (-b/-B) option checking
  worktree: improve worktree setup message
  branch: publish die_if_checked_out()
  checkout: teach check_linked_checkout() about symbolic link HEAD
  checkout: check_linked_checkout: simplify symref parsing
  checkout: check_linked_checkout: improve "already checked out" aesthetic
  ...

Rewrite "am" in "C".

* pt/am-builtin: (46 commits)
  git-am: add am.threeWay config variable
  builtin-am: remove redirection to git-am.sh
  builtin-am: check for valid committer ident
  builtin-am: implement legacy -b/--binary option
  builtin-am: implement -i/--interactive
  builtin-am: support and auto-detect mercurial patches
  builtin-am: support and auto-detect StGit series files
  builtin-am: support and auto-detect StGit patches
  builtin-am: rerere support
  builtin-am: invoke post-applypatch hook
  builtin-am: invoke pre-applypatch hook
  builtin-am: invoke applypatch-msg hook
  builtin-am: support automatic notes copying
  builtin-am: invoke post-rewrite hook
  builtin-am: implement -S/--gpg-sign, commit.gpgsign
  builtin-am: implement --committer-date-is-author-date
  builtin-am: implement --ignore-date
  builtin-am: pass git-apply's options to git-apply
  builtin-am: implement --[no-]scissors
  builtin-am: support --keep-cr, am.keepcr
  ...

Remove remaining cruft from  "git checkout --to", which
transitioned to "git worktree add".

* es/worktree-add:
  config: rename "gc.pruneWorktreesExpire" to "gc.worktreePruneExpire"
  Documentation/git-worktree: wordsmith worktree-related manpages
  Documentation/config: fix stale "git prune --worktree" reference
  Documentation/git-worktree: fix incorrect reference to file "locked"
  Documentation/git-worktree: consistently use term "linked working tree"

Code and documentation clean-up to "git bisect".

* ad/bisect-cleanup:
  bisect: don't mix option parsing and non-trivial code
  bisect: simplify the addition of new bisect terms
  bisect: replace hardcoded "bad|good" by variables
  Documentation/bisect: revise overall content
  Documentation/bisect: move getting help section to the end
  bisect: correction of typo

During cleanup we do a simple 'rm /*' to remove leftover files
from previous tests. As 'rm' errors out when there is anything it
cannot delete and there are directories present at '/' it will
throw an error, causing the '&&' chain to fail.

Fix this by explicitly removing the files.
Signed-off-by: NPatrick Steinhardt <ps@pks.im>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NPatrick Steinhardt <ps@pks.im>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NPatrick Steinhardt <ps@pks.im>
Acked-by: NEric Sunshine <sunshine@sunshineco.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Add the am.threeWay configuration variable to use the -3 or --3way
option of git am by default. When am.threeway is set and not desired
for a specific git am command, the --no-3way option can be used to
override it.
Signed-off-by: NRemi Lespinet <remi.lespinet@ensimag.grenoble-inp.fr>
Signed-off-by: NPaul Tan <pyokagan@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

At the beginning of the rewrite of git-am.sh to C, in order to not break
existing test scripts that depended on a functional git-am, a
redirection to git-am.sh was introduced that would activate if the
environment variable _GIT_USE_BUILTIN_AM was not defined.

Now that all of git-am.sh's functionality has been re-implemented in
builtin/am.c, remove this redirection, and retire git-am.sh into
contrib/examples/.
Signed-off-by: NPaul Tan <pyokagan@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

When commit_tree() is called, if the user does not have an explicit
committer ident configured, it will attempt to construct a default
committer ident based on the user's and system's info (e.g. gecos field,
hostname etc.) However, if a default committer ident is unable to be
constructed, commit_tree() will die(), but at this point of git-am's
execution, there will already be changes made to the index and work
tree.

This can be confusing to new users, and as such since d64e6b04 (Keep
Porcelainish from failing by broken ident after making changes.,
2006-02-18) git-am.sh will check to see if the committer ident has been
configured, or a default one can be constructed, before even starting to
apply patches.

Re-implement this in builtin/am.c.
Signed-off-by: NPaul Tan <pyokagan@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The -b/--binary option was initially implemented in 087b6742 (git-am:
--binary; document --resume and --binary., 2005-11-16). The option will
pass the --binary flag to git-apply to allow it to apply binary patches.

However, in 2b6eef94 (Make apply --binary a no-op., 2006-09-06), --binary
was been made a no-op in git-apply. Following that, since cb3a160d
(git-am: ignore --binary option, 2008-08-09), the --binary option in
git-am is ignored as well.

In 6c15a1c6 (am: officially deprecate -b/--binary option, 2012-03-13),
the --binary option was tweaked to its present behavior: when set, the
message:

	The -b/--binary option has been a no-op for long time, and it
	will be removed. Please do not use it anymore.

will be printed.

Re-implement this in builtin/am.c.
Signed-off-by: NPaul Tan <pyokagan@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Since d1c5f2a4 (Add git-am, applymbox replacement., 2005-10-07),
git-am.sh supported the --interactive mode. After parsing the patch mail
and extracting the patch, commit message and authorship info, an
interactive session will begin that allows the user to choose between:

* applying the patch

* applying the patch and all subsequent patches (by disabling
  interactive mode in subsequent patches)

* skipping the patch

* editing the commit message

Since f89ad67f (Add [v]iew patch in git-am interactive., 2005-10-25),
git-am.sh --interactive also supported viewing the patch to be applied.

When --resolved-ing in --interactive mode, we need to take care to
update the patch with the contents of the index, such that the correct
patch will be displayed when the patch is viewed in interactive mode.

Re-implement the above in builtin/am.c
Signed-off-by: NPaul Tan <pyokagan@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Since 0cfd1120 (am: preliminary support for hg patches, 2011-08-29),
git-am.sh could convert mercurial patches to an RFC2822 mail patch
suitable for parsing with git-mailinfo, and queue them in the state
directory for application.

Since 15ced753 (git-am foreign patch support: autodetect some patch
formats, 2009-05-27), git-am.sh was able to auto-detect mercurial
patches by checking if the file begins with the line:

	# HG changeset patch

Re-implement the above in builtin/am.c.
Helped-by: NStefan Beller <sbeller@google.com>
Signed-off-by: NPaul Tan <pyokagan@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Since c574e683 (git-am foreign patch support: StGIT support, 2009-05-27),
git-am.sh is able to read a single StGit series file and, for each StGit
patch listed in the file, convert the StGit patch into a RFC2822 mail
patch suitable for parsing with git-mailinfo, and queue them in the
state directory for applying.

Since 15ced753 (git-am foreign patch support: autodetect some patch
formats, 2009-05-27), git-am.sh is able to auto-detect StGit series
files by checking to see if the file starts with the string:

	# This series applies on GIT commit

Re-implement the above in builtin/am.c.
Signed-off-by: NPaul Tan <pyokagan@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Since c574e683 (git-am foreign patch support: StGIT support, 2009-05-27),
git-am.sh supported converting StGit patches into RFC2822 mail patches
that can be parsed with git-mailinfo.

Implement this by introducing two functions in builtin/am.c:
stgit_patch_to_mail() and split_mail_conv().

stgit_patch_to_mail() is a callback function for split_mail_conv(), and
contains the logic for converting an StGit patch into an RFC2822 mail
patch.

split_mail_conv() implements the logic to go through each file in the
`paths` list, reading from stdin where specified, and calls the callback
function to write the converted patch to the corresponding output file
in the state directory. This interface should be generic enough to
support other foreign patch formats in the future.

Since 15ced753 (git-am foreign patch support: autodetect some patch
formats, 2009-05-27), git-am.sh is able to auto-detect StGit patches.
Re-implement this in builtin/am.c.
Helped-by: NEric Sunshine <sunshine@sunshineco.com>
Signed-off-by: NPaul Tan <pyokagan@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

git-am.sh will call git-rerere at the following events:

* "git rerere" when a three-way merge fails to record the conflicted
  automerge results. Since 8389b52b (git-rerere: reuse recorded resolve.,
  2006-01-28)

  * Since cb6020bb (Teach --[no-]rerere-autoupdate option to merge,
    revert and friends, 2009-12-04), git-am.sh supports the
    --[no-]rerere-autoupdate option as well, and would pass it to
    git-rerere.

* "git rerere" when --resolved, to record the hand resolution. Since
  f131dd49 (rerere: record (or avoid misrecording) resolved, skipped or
  aborted rebase/am, 2006-12-08)

* "git rerere clear" when --skip-ing. Since f131dd49 (rerere: record (or
  avoid misrecording) resolved, skipped or aborted rebase/am,
  2006-12-08)

* "git rerere clear" when --abort-ing. Since 3e5057a8 (git am --abort,
  2008-07-16)

Re-implement the above in builtin/am.c.
Signed-off-by: NPaul Tan <pyokagan@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Since d1c5f2a4 (Add git-am, applymbox replacement., 2005-10-07),
git-am.sh will invoke the post-applypatch hook after the patch is
applied and a commit is made. The exit code of the hook is ignored.

Re-implement this in builtin/am.c.
Signed-off-by: NPaul Tan <pyokagan@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Since d1c5f2a4 (Add git-am, applymbox replacement., 2005-10-07),
git-am.sg will invoke the pre-applypatch hook after applying the patch
to the index, but before a commit is made. Should the hook exit with a
non-zero status, git am will exit.

Re-implement this in builtin/am.c.
Signed-off-by: NPaul Tan <pyokagan@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Since d1c5f2a4 (Add git-am, applymbox replacement., 2005-10-07),
git-am.sh will invoke the applypatch-msg hooks just after extracting the
patch message. If the applypatch-msg hook exits with a non-zero status,
git-am.sh abort before even applying the patch to the index.

Re-implement this in builtin/am.c.
Signed-off-by: NPaul Tan <pyokagan@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Since eb2151bb (rebase: support automatic notes copying, 2010-03-12),
git-am.sh supported automatic notes copying in --rebasing mode by
invoking "git notes copy" once it has finished applying all the patches.

Re-implement this feature in builtin/am.c.
Signed-off-by: NPaul Tan <pyokagan@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Since 96e19488 (rebase: invoke post-rewrite hook, 2010-03-12), git-am.sh
will invoke the post-rewrite hook after it successfully finishes
applying all the queued patches.

To do this, when parsing a mail to extract its patch and metadata, in
--rebasing mode git-am.sh will also store the original commit ID in the
$state_dir/original-commit file. Once it applies and commits the patch,
the original commit ID, and the new commit ID, will be appended to the
$state_dir/rewritten file.

Once all of the queued mail have been processed, git-am.sh will then
invoke the post-rewrite hook with the contents of the
$state_dir/rewritten file.

Re-implement this in builtin/am.c.
Signed-off-by: NPaul Tan <pyokagan@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Since 3b4e395f (am: add the --gpg-sign option, 2014-02-01), git-am.sh
supported the --gpg-sign option, and would pass it to git-commit-tree,
thus GPG-signing the commit object.

Re-implement this option in builtin/am.c.

git-commit-tree would also sign the commit by default if the
commit.gpgsign setting is true. Since we do not run commit-tree, we
re-implement this behavior by handling the commit.gpgsign setting
ourselves.
Helped-by: NStefan Beller <sbeller@google.com>
Signed-off-by: NPaul Tan <pyokagan@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Since 3f01ad66 (am: Add --committer-date-is-author-date option,
2009-01-22), git-am.sh implemented the --committer-date-is-author-date
option, which tells git-am to use the timestamp recorded in the email
message as both author and committer date.

Re-implement this option in builtin/am.c.
Signed-off-by: NPaul Tan <pyokagan@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Since a79ec62d (git-am: Add --ignore-date option, 2009-01-24), git-am.sh
supported the --ignore-date option, and would use the current timestamp
instead of the one provided in the patch if the option was set.

Re-implement this option in builtin/am.c.
Signed-off-by: NPaul Tan <pyokagan@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

git-am.sh recognizes some of git-apply's options, and would pass them to
git-apply:

* --whitespace, since 8c31cb82 (git-am: --whitespace=x option.,
  2006-02-28)

* -C, since 67dad687 (add -C[NUM] to git-am, 2007-02-08)

* -p, since 2092a1fe (Teach git-am to pass -p option down to git-apply,
  2007-02-11)

* --directory, since b47dfe9e (git-am: add --directory=<dir> option,
  2009-01-11)

* --reject, since b80da424 (git-am: implement --reject option passed to
  git-apply, 2009-01-23)

* --ignore-space-change, --ignore-whitespace, since 86c91f91 (git apply:
  option to ignore whitespace differences, 2009-08-04)

* --exclude, since 77e9e496 (am: pass exclude down to apply, 2011-08-03)

* --include, since 58725efd (am: support --include option, 2012-03-28)

* --reject, since b80da424 (git-am: implement --reject option passed to
  git-apply, 2009-01-23)

Re-implement support for these options in builtin/am.c.
Signed-off-by: NPaul Tan <pyokagan@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Since 017678b4 (am/mailinfo: Disable scissors processing by default,
2009-08-26), git-am supported the --[no-]scissors option, passing it to
git-mailinfo.

Re-implement support for this option in builtin/am.c.

Since the default setting of --scissors in git-mailinfo can be
configured with mailinfo.scissors (and perhaps through other settings in
the future), to be safe we make an explicit distinction between
SCISSORS_UNSET, SCISSORS_TRUE and SCISSORS_FALSE.
Signed-off-by: NPaul Tan <pyokagan@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Since ad2c9280 (git-am: Add command line parameter `--keep-cr` passing it
to git-mailsplit, 2010-02-27), git-am.sh supported the --keep-cr option
and would pass it to git-mailsplit.

Since e80d4cbe (git-am: Add am.keepcr and --no-keep-cr to override it,
2010-02-27), git-am.sh supported the am.keepcr config setting, which
controls whether --keep-cr is on by default.

Re-implement the above in builtin/am.c.
Signed-off-by: NPaul Tan <pyokagan@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>