The code to learn the list of merge strategies from the output of
"git merge -s help" forces C locale, so that it can notice the
message shown to indicate where the list starts in the output.

However, GETTEXT_POISON build corrupts its output even when run in
the C locale, and we cannot expect this test to succeed.

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

The established way to update the completion script in an already
running shell is to simply source it again: this brings in any new
--options and features, and clears caching variables.  E.g. it clears
the variables caching the list of (all|porcelain) git commands, so
when they are later lazy-initialized again, then they will list and
cache any newly installed commmands as well.

Unfortunately, since d401f3de (git-completion.bash: introduce
__gitcomp_builtin, 2018-02-09) and subsequent patches this doesn't
work for a lot of git commands' options.  To eliminate a lot of
hard-to-maintain hard-coded lists of options, those commits changed
the completion script to use a bunch of programmatically created and
lazy-initialized variables to cache the options of those builtin
porcelain commands that use parse-options.  These variables are not
cleared upon sourcing the completion script, therefore they continue
caching the old lists of options, even when some commands recently
learned new options or when deprecated options were removed.

Always 'unset' these variables caching the options of builtin commands
when sourcing the completion script.

Redirect 'unset's stderr to /dev/null, because ZSH's 'unset' complains
if it's invoked without any arguments, i.e. no variables caching
builtin's options are set.  This can happen, if someone were to source
the completion script twice without completing any --options in
between.  Bash stays silent in this case.

Add tests to ensure that these variables are indeed cleared when the
completion script is sourced; not just the variables caching options,
but all other caching variables, i.e. the variables caching commands,
porcelain commands and merge strategies as well.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Two subcommands are added for completion: merge and get-ref. get-ref
is more like plumbing. But since it does not share the prefix with any
other subcommands, it won't slow anybody down.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The new subcommand that takes these options is 'git notes edit'. Just
accept the options from subcommands since we handle them the same way
in builtin/notes.c anyway. If a user does

    git prune --reuse-message=...

just let the command catches that error when it's executed.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

This also adds completion for 'git notes remove' and 'git notes edit'.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

There is not a strong reason to hide this option, and git-merge already
completes this one. Let's allow to complete this for all commands (and
let git-completion.bash do the suppressing if needed).

This makes --rerere-autoupdate completable for am, cherry-pick and
revert. rebase completion is fixed manually because it's a shell
script and does not benefit from --git-completion-helper.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The new completable options for "worktree add" are:

--checkout
--guess-remote
--lock
--track

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The new completable options are:

--color
--format=
--ignore-case

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The new completable options are --null and --show-stash.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

No new completable options!

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

No new completable options!

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The new completable option is --gpg-sign

In-progress options like --continue will be part of --git-completion-helper
then filtered out by _git_revert() unless the operation is in
progress. This helps keep marking of these operations in just one place.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The new completable options are:

--intent-to-add
--quiet
--recurse-submodules

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The new completable option is --raw.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

"git remote --mirror" is a special case. Technically it is possible to
specify --mirror without any argument. But we will get a "dangerous,
deprecated!" warning in that case.

This new parse-opt flag allows --git-completion-helper to always
complete --mirror=, ignoring the dangerous use case.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

No new completable options!

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The new completable options are:

--atomic
--exec=
--ipv4
--ipv6
--no-verify
--porcelain
--progress
--push-option
--signed

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

This is really nice. Since pull_options[] already declares all
passthru options to 'merge' or 'fetch', a single

    git pull --git-completion-helper

would provide all completable options (--no- variants are a separate
issue). Dead shell variables can now be deleted.

New completable options are:

--allow-unrelated-histories
--ipv4
--ipv6
--jobs
--refmap=
--signoff
--strategy-option=

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The new completable options are:

--allow-empty (notes add and notes append)
--for-rewrite= (notes copy)

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The new completable options are:

--always
--exclude
--name-only
--refs
--undefined

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The new completable option is --verbose.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The new completion option is --all.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

New completable options are:

--allow-unrelated-histories
--message=
--overwrite-ignore
--signoff
--strategy-option=
--summary
--verify

The variable $__git_merge_options remains because _git_pull() still
needs it. It will soon be gone after _git_pull() is updated.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The new completable options are --quiet and --upload-pack=.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The new completable options are:

--debug
--empty-directory
--eol
--recurse-submodules
--resolve-undo

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The new completable option is --separate-git-dir=.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

No new completable options!

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The new completable options are:

--after-context=
--before-context=
--color
--context
--exclude-standard
--quiet
--recurse-submodules
--textconv

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The new completable option is --quiet.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The new completable options are:

--connectivity-only
--dangling
--progress
--reflogs

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

New completable options:

--deepen=
--ipv4
--ipv6
--jobs=
--multiple
--progress
--refmap=
--shallow-exclude=
--shallow-since=
--update-head-ok

Since _git_pull() needs fetch options too, $__git_fetch_options
remains. This variable will soon be gone after _git_pull() is updated.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Since we can't automatically extract diff options for completion yet,
difftool will take all options from $__git_diff_common_options. This
brings _a lot_ more completable options to difftool.

--ignore-submodules is added to $__git_diff_common_options to avoid
regression in difftool. But it's a good thing anyway even for other
diff commands.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

No new completable options!

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The new completable options are:

--blob=
--bool
--bool-or-int
--edit
--expiry-date
--get-color
--get-colorbool
--get-urlmatch
--includes
--int
--null
--path
--show-origin

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The new comletable options are:

--branch
--gpg-sign
--long
--no-post-rewrite
--null
--porcelain
--status

--allow-empty is no longer completable because it's a hidden option
since 4741edd5 (Remove deprecated OPTION_BOOLEAN for parsing arguments
- 2013-08-03)

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The new completable options are:

--config
--dissociate
--ipv4
--ipv6
--jobs=
--progress
--reference-if-able
--separate-git-dir=
--shallow-exclude
--shallow-since=
--verbose

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The new completable options are --exclude and --interactive

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The new completable options are:

--allow-empty
--allow-empty-message
--ff
--gpg-sign
--keep-redundant-commits
--strategy-option

In-progress options like --continue will be part of --git-completion-helper
then filtered out by _git_cherry_pick() unless the operation is in
progress. This helps keep marking of these operations in just one place.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The new completable options are:

--ignore-other-worktrees
--progress

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The new completable options are:

--all
--create-reflog
--format=
--ignore-case
--quiet

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>