#!/bin/sh
#
# Copyright (c) 2005 Junio C Hamano
#
# Fetch one or more remote refs and merge it/them into the current HEAD.

setglobal SUBDIRECTORY_OK = 'Yes'
setglobal OPTIONS_KEEPDASHDASH = ''
setglobal OPTIONS_STUCKLONG = 'Yes'
setglobal OPTIONS_SPEC = '"\
git pull [options] [<repository> [<refspec>...]]

Fetch one or more remote refs and integrate it/them with the current HEAD.
--
v,verbose                  be more verbose
q,quiet                    be more quiet
progress                   force progress reporting

  Options related to merging
r,rebase?false|true|preserve incorporate changes by rebasing rather than merging
n!                         do not show a diffstat at the end of the merge
stat                       show a diffstat at the end of the merge
summary                    (synonym to --stat)
log?n                      add (at most <n>) entries from shortlog to merge commit message
squash                     create a single commit instead of doing a merge
commit                     perform a commit if the merge succeeds (default)
e,edit                       edit message before committing
ff                         allow fast-forward
ff-only!                   abort if fast-forward is not possible
verify-signatures          verify that the named commit has a valid GPG signature
s,strategy=strategy        merge strategy to use
X,strategy-option=option   option for selected merge strategy
S,gpg-sign?key-id          GPG sign commit

  Options related to fetching
all                        fetch from all remotes
a,append                   append to .git/FETCH_HEAD instead of overwriting
upload-pack=path           path to upload pack on remote end
f,force                    force overwrite of local branch
t,tags                     fetch all tags and associated objects
p,prune                    prune remote-tracking branches no longer on remote
recurse-submodules?on-demand control recursive fetching of submodules
dry-run                    dry run
k,keep                     keep downloaded pack
depth=depth                deepen history of shallow clone
unshallow                  convert to a complete repository
update-shallow             accept refs that update .git/shallow
refmap=refmap              specify fetch refmap
'"
test $Argc -gt 0 && setglobal args = "$ifsjoin(Argv)"
source git-sh-setup
source git-sh-i18n
set_reflog_action "pull$(args+ $args)"
require_work_tree_exists
cd_to_toplevel


proc die_conflict {
    git diff-index --cached --name-status -r --ignore-submodules HEAD --
    if test $[git config --bool --get advice.resolveConflict || echo true] = "true" {
	die $[gettext "Pull is not possible because you have unmerged files.
Please, fix them up in the work tree, and then use 'git add/rm <file>'
as appropriate to mark resolution and make a commit.]
    } else {
	die $[gettext "Pull is not possible because you have unmerged files.]
    }
}

proc die_merge {
    if test $[git config --bool --get advice.resolveConflict || echo true] = "true" {
	die $[gettext "You have not concluded your merge (MERGE_HEAD exists).
Please, commit your changes before merging.]
    } else {
	die $[gettext "You have not concluded your merge (MERGE_HEAD exists).]
    }
}

test -z $[git ls-files -u] || die_conflict
test -f "$GIT_DIR/MERGE_HEAD" && die_merge

proc bool_or_string_config {
	git config --bool $1 !2 >/dev/null || git config $1
}

setglobal strategy_args = '', diffstat = '', no_commit = '', squash = '', no_ff = '', ff_only = ''
setglobal log_arg = '', verbosity = '', progress = '', recurse_submodules = '', verify_signatures = ''
setglobal merge_args = '', edit = '', rebase_args = '', all = '', append = '', upload_pack = '', force = '', tags = '', prune = ''
setglobal keep = '', depth = '', unshallow = '', update_shallow = '', refmap = ''
setglobal curr_branch = $[git symbolic-ref -q HEAD]
setglobal curr_branch_short = $(curr_branch#refs/heads/)
setglobal rebase = $[bool_or_string_config branch.$curr_branch_short.rebase]
if test -z $rebase
{
	setglobal rebase = $[bool_or_string_config pull.rebase]
}

# Setup default fast-forward options via `pull.ff`
setglobal pull_ff = $[bool_or_string_config pull.ff]
match $pull_ff {
with true
	setglobal no_ff = '--ff'
	
with false
	setglobal no_ff = '--no-ff'
	
with only
	setglobal ff_only = '--ff-only'
	
}


setglobal dry_run = ''
while :
{
	match $1 {
	with -q|--quiet
		setglobal verbosity = ""$verbosity -q"" 
	with -v|--verbose
		setglobal verbosity = ""$verbosity -v"" 
	with --progress
		setglobal progress = '--progress' 
	with --no-progress
		setglobal progress = '--no-progress' 
	with -n|--no-stat|--no-summary
		setglobal diffstat = '--no-stat' 
	with --stat|--summary
		setglobal diffstat = '--stat' 
	with --log|--log=*|--no-log
		setglobal log_arg = $1 
	with --no-commit
		setglobal no_commit = '--no-commit' 
	with --commit
		setglobal no_commit = '--commit' 
	with -e|--edit
		setglobal edit = '--edit' 
	with --no-edit
		setglobal edit = '--no-edit' 
	with --squash
		setglobal squash = '--squash' 
	with --no-squash
		setglobal squash = '--no-squash' 
	with --ff
		setglobal no_ff = '--ff' 
	with --no-ff
		setglobal no_ff = '--no-ff' 
	with --ff-only
		setglobal ff_only = '--ff-only' 
	with -s*|--strategy=*
		setglobal strategy_args = ""$strategy_args $1""
		
	with -X*|--strategy-option=*
		setglobal merge_args = ""$merge_args $[git rev-parse --sq-quote $1]""
		
	with -r*|--rebase=*
		setglobal rebase = $(1#*=)
		
	with --rebase
		setglobal rebase = 'true'
		
	with --no-rebase
		setglobal rebase = 'false'
		
	with --recurse-submodules
		setglobal recurse_submodules = '--recurse-submodules'
		
	with --recurse-submodules=*
		setglobal recurse_submodules = $1
		
	with --no-recurse-submodules
		setglobal recurse_submodules = '--no-recurse-submodules'
		
	with --verify-signatures
		setglobal verify_signatures = '--verify-signatures'
		
	with --no-verify-signatures
		setglobal verify_signatures = '--no-verify-signatures'
		
	with --gpg-sign|-S
		setglobal gpg_sign_args = '-S'
		
	with --gpg-sign=*
		setglobal gpg_sign_args = $[git rev-parse --sq-quote "-S$(1#--gpg-sign=)]
		
	with -S*
		setglobal gpg_sign_args = $[git rev-parse --sq-quote $1]
		
	with --dry-run
		setglobal dry_run = '--dry-run'
		
	with --all|--no-all
		setglobal all = $1 
	with -a|--append|--no-append
		setglobal append = $1 
	with --upload-pack=*|--no-upload-pack
		setglobal upload_pack = $1 
	with -f|--force|--no-force
		setglobal force = ""$force $1"" 
	with -t|--tags|--no-tags
		setglobal tags = $1 
	with -p|--prune|--no-prune
		setglobal prune = $1 
	with -k|--keep|--no-keep
		setglobal keep = $1 
	with --depth=*|--no-depth
		setglobal depth = $1 
	with --unshallow|--no-unshallow
		setglobal unshallow = $1 
	with --update-shallow|--no-update-shallow
		setglobal update_shallow = $1 
	with --refmap=*|--no-refmap
		setglobal refmap = $1 
	with -h|--help-all
		usage
		
	with --
		shift
		break
		
	with *
		usage
		
	}
	shift
}

match $rebase {
with preserve
	setglobal rebase = 'true'
	setglobal rebase_args = '--preserve-merges'
	
with true|false|''
	
with *
	echo "Invalid value for --rebase, should be true, false, or preserve"
	usage
	exit 1
	
}

proc error_on_no_merge_candidates {
	exec > !2

	if test true = $rebase
	{
		setglobal op_type = 'rebase'
		setglobal op_prep = 'against'
	} else {
		setglobal op_type = 'merge'
		setglobal op_prep = 'with'
	}

	setglobal upstream = $[git config "branch.$curr_branch_short.merge]
	setglobal remote = $[git config "branch.$curr_branch_short.remote]

	if test $Argc -gt 1 {
		if test $rebase = true {
			printf "There is no candidate for rebasing against "
		} else {
			printf "There are no candidates for merging "
		}
		echo "among the refs that you just fetched."
		echo "Generally this means that you provided a wildcard refspec which had no"
		echo "matches on the remote end."
	} elif test $Argc -gt 0 && test $1 != $remote {
		echo "You asked to pull from the remote '$1', but did not specify"
		echo "a branch. Because this is not the default configured remote"
		echo "for your current branch, you must specify a branch on the command line."
	} elif test -z $curr_branch -o -z $upstream {
		source git-parse-remote
		error_on_missing_default_upstream "pull" $op_type $op_prep \
			"git pull <remote> <branch>"
	} else {
		echo "Your configuration specifies to $op_type $op_prep the ref '$(upstream#refs/heads/)'"
		echo "from the remote, but no such ref was fetched."
	}
	exit 1
}

test true = $rebase && do {
	if ! git rev-parse -q --verify HEAD >/dev/null
	{
		# On an unborn branch
		if test -f $[git rev-parse --git-path index]
		{
			die $[gettext "updating an unborn branch with changes added to the index]
		}
	} else {
		require_clean_work_tree "pull with rebase" "Please commit or stash them."
	}
	setglobal oldremoteref = '' &&
	test -n $curr_branch &&
	source git-parse-remote &&
	setglobal remoteref = $[get_remote_merge_branch @Argv !2 >/dev/null] &&
	setglobal oldremoteref = $[git merge-base --fork-point $remoteref $curr_branch !2 >/dev/null]
}
setglobal orig_head = $[git rev-parse -q --verify HEAD]
git fetch $verbosity $progress $dry_run $recurse_submodules $all $append \
$(upload_pack:+"$upload_pack") $force $tags $prune $keep $depth $unshallow $update_shallow \
$refmap --update-head-ok @Argv || exit 1
test -z $dry_run || exit 0

setglobal curr_head = $[git rev-parse -q --verify HEAD]
if test -n $orig_head && test $curr_head != $orig_head
{
	# The fetch involved updating the current branch.

	# The working tree and the index file is still based on the
	# $orig_head commit, but we are merging into $curr_head.
	# First update the working tree to match $curr_head.

	eval_gettextln "Warning: fetch updated the current branch head.
Warning: fast-forwarding your working tree from
Warning: commit \$orig_head." > !2
	git update-index -q --refresh
	git read-tree -u -m $orig_head $curr_head ||
		die $[eval_gettext "Cannot fast-forward your working tree.
After making sure that you saved anything precious from
$ git diff \$orig_head
output, run
$ git reset --hard
to recover.]

}

setglobal merge_head = $[sed -e '/	not-for-merge	/d' \
	-e 's/	.*//' "$GIT_DIR"/FETCH_HEAD | \
	tr '\012' ' ]

match $merge_head {
with ''
	error_on_no_merge_candidates @Argv
	
with ?*' '?*
	if test -z $orig_head
	{
		die $[gettext "Cannot merge multiple branches into empty head]
	}
	if test true = $rebase
	{
		die $[gettext "Cannot rebase onto multiple branches]
	}
	
}

# Pulling into unborn branch: a shorthand for branching off
# FETCH_HEAD, for lazy typers.
if test -z $orig_head
{
	# Two-way merge: we claim the index is based on an empty tree,
	# and try to fast-forward to HEAD.  This ensures we will not
	# lose index/worktree changes that the user already made on
	# the unborn branch.
	setglobal empty_tree = '4b825dc642cb6eb9a060e54bf8d69288fbee4904'
	git read-tree -m -u $empty_tree $merge_head &&
	git update-ref -m "initial pull" HEAD $merge_head $curr_head
	exit
}

if test true = $rebase
{
	setglobal o = $[git show-branch --merge-base $curr_branch $merge_head $oldremoteref]
	if test $oldremoteref = $o
	{
		unset oldremoteref
	}
}

match $rebase {
with true
	setglobal eval = ""git-rebase $diffstat $strategy_args $merge_args $rebase_args $verbosity""
	setglobal eval = ""$eval $gpg_sign_args""
	setglobal eval = ""$eval --onto $merge_head $(oldremoteref:-$merge_head)""
	
with *
	setglobal eval = ""git-merge $diffstat $no_commit $verify_signatures $edit $squash $no_ff $ff_only""
	setglobal eval = ""$eval $log_arg $strategy_args $merge_args $verbosity $progress""
	setglobal eval = ""$eval $gpg_sign_args""
	setglobal eval = ""$eval FETCH_HEAD""
	
}
eval "exec $eval"