Alter git-checkout reflog message to include "from" branch
[git/git.git] / git-checkout.sh
CommitLineData
303e5f4c 1#!/bin/sh
b33e9666 2
6124aee5 3USAGE='[-q] [-f] [-b <new_branch>] [-m] [<branch>] [<paths>...]'
104f3e03 4SUBDIRECTORY_OK=Sometimes
806f36d4 5. git-sh-setup
7eff28a9 6require_work_tree
b0bafe03 7
969d326d 8old_name=HEAD
5be60078
JH
9old=$(git rev-parse --verify $old_name 2>/dev/null)
10oldbranch=$(git symbolic-ref $old_name 2>/dev/null)
e8b11749 11new=
969d326d 12new_name=
a79944d7 13force=
e8b11749 14branch=
0746d19a 15track=
91dcdfd3 16newbranch=
969d326d 17newbranch_log=
1be0659e 18merge=
6124aee5 19quiet=
4c474b6f 20v=-v
ead80606
JH
21LF='
22'
e8b11749
LT
23while [ "$#" != "0" ]; do
24 arg="$1"
25 shift
26 case "$arg" in
91dcdfd3
LT
27 "-b")
28 newbranch="$1"
29 shift
30 [ -z "$newbranch" ] &&
31 die "git checkout: -b needs a branch name"
5be60078 32 git show-ref --verify --quiet -- "refs/heads/$newbranch" &&
91dcdfd3 33 die "git checkout: branch $newbranch already exists"
5be60078 34 git check-ref-format "heads/$newbranch" ||
babfaf8d 35 die "git checkout: we do not like '$newbranch' as a branch name."
91dcdfd3 36 ;;
969d326d 37 "-l")
0746d19a
PB
38 newbranch_log=-l
39 ;;
40 "--track"|"--no-track")
41 track="$arg"
969d326d 42 ;;
303e5f4c 43 "-f")
e8b11749 44 force=1
303e5f4c 45 ;;
1be0659e
JH
46 -m)
47 merge=1
48 ;;
6124aee5
NP
49 "-q")
50 quiet=1
4c474b6f 51 v=
6124aee5 52 ;;
4aaa7027
JH
53 --)
54 break
55 ;;
b0bafe03
CS
56 -*)
57 usage
58 ;;
303e5f4c 59 *)
5be60078 60 if rev=$(git rev-parse --verify "$arg^0" 2>/dev/null)
4aaa7027
JH
61 then
62 if [ -z "$rev" ]; then
63 echo "unknown flag $arg"
64 exit 1
65 fi
8d78b5af 66 new_name="$arg"
5be60078 67 if git show-ref --verify --quiet -- "refs/heads/$arg"
305e22c3 68 then
5be60078 69 rev=$(git rev-parse --verify "refs/heads/$arg^0")
4aaa7027
JH
70 branch="$arg"
71 fi
5035242c 72 new="$rev"
5be60078 73 elif rev=$(git rev-parse --verify "$arg^{tree}" 2>/dev/null)
4aaa7027
JH
74 then
75 # checking out selected paths from a tree-ish.
76 new="$rev"
969d326d 77 new_name="$arg^{tree}"
4aaa7027
JH
78 branch=
79 else
80 new=
969d326d 81 new_name=
4aaa7027
JH
82 branch=
83 set x "$arg" "$@"
84 shift
e8b11749 85 fi
2608003f
JH
86 case "$1" in
87 --)
88 shift ;;
89 esac
4aaa7027 90 break
e8b11749 91 ;;
303e5f4c 92 esac
303e5f4c
LT
93done
94
9debc324 95case "$newbranch,$track" in
0746d19a
PB
96,--*)
97 die "git checkout: --track and --no-track require -b"
98esac
99
897643cc
JH
100case "$force$merge" in
10111)
102 die "git checkout: -f and -m are incompatible"
103esac
104
4aaa7027
JH
105# The behaviour of the command with and without explicit path
106# parameters is quite different.
107#
108# Without paths, we are checking out everything in the work tree,
109# possibly switching branches. This is the traditional behaviour.
91dcdfd3 110#
4aaa7027
JH
111# With paths, we are _never_ switching branch, but checking out
112# the named paths from either index (when no rev is given),
113# or the named tree-ish (when rev is given).
114
115if test "$#" -ge 1
116then
babfaf8d
JW
117 hint=
118 if test "$#" -eq 1
119 then
120 hint="
121Did you intend to checkout '$@' which can not be resolved as commit?"
122 fi
1be0659e 123 if test '' != "$newbranch$force$merge"
4aaa7027 124 then
babfaf8d 125 die "git checkout: updating paths is incompatible with switching branches/forcing$hint"
4aaa7027
JH
126 fi
127 if test '' != "$new"
128 then
129 # from a specific tree-ish; note that this is for
130 # rescuing paths and is never meant to remove what
131 # is not in the named tree-ish.
5be60078
JH
132 git ls-tree --full-name -r "$new" "$@" |
133 git update-index --index-info || exit $?
4aaa7027 134 fi
bf7e1472
JH
135
136 # Make sure the request is about existing paths.
5be60078
JH
137 git ls-files --error-unmatch -- "$@" >/dev/null || exit
138 git ls-files -- "$@" |
139 git checkout-index -f -u --stdin
4aaa7027
JH
140 exit $?
141else
142 # Make sure we did not fall back on $arg^{tree} codepath
143 # since we are not checking out from an arbitrary tree-ish,
144 # but switching branches.
145 if test '' != "$new"
146 then
5be60078 147 git rev-parse --verify "$new^{commit}" >/dev/null 2>&1 ||
4aaa7027
JH
148 die "Cannot switch branch to a non-commit."
149 fi
150fi
151
104f3e03
JH
152# We are switching branches and checking out trees, so
153# we *NEED* to be at the toplevel.
514c09fd 154cd_to_toplevel
104f3e03 155
969d326d 156[ -z "$new" ] && new=$old && new_name="$old_name"
4aaa7027 157
73c838e4 158# If we don't have an existing branch that we're switching to,
91dcdfd3 159# and we don't have a new branch name for the target we
73c838e4
JH
160# are switching to, then we are detaching our HEAD from any
161# branch. However, if "git checkout HEAD" detaches the HEAD
162# from the current branch, even though that may be logically
163# correct, it feels somewhat funny. More importantly, we do not
164# want "git checkout" nor "git checkout -f" to detach HEAD.
4aaa7027 165
bfbbb8f8
JH
166detached=
167detach_warn=
168
abba9dbb
JH
169describe_detached_head () {
170 test -n "$quiet" || {
171 printf >&2 "$1 "
172 GIT_PAGER= git log >&2 -1 --pretty=oneline --abbrev-commit "$2"
173 }
174}
175
3e0318a3 176if test -z "$branch$newbranch" && test "$new_name" != "$old_name"
c847f537 177then
bfbbb8f8 178 detached="$new"
6124aee5 179 if test -n "$oldbranch" && test -z "$quiet"
64886104 180 then
92cf9569 181 detach_warn="Note: moving to \"$new_name\" which isn't a local branch
d117452a
NP
182If you want to create a new branch from this checkout, you may do so
183(now or later) by using -b with the checkout command again. Example:
eb3204df 184 git checkout -b <new_branch_name>"
64886104 185 fi
3e0318a3 186elif test -z "$oldbranch" && test "$new" != "$old"
ead80606 187then
abba9dbb 188 describe_detached_head 'Previous HEAD position was' "$old"
c847f537 189fi
91dcdfd3 190
5a03e7f2
SP
191if [ "X$old" = X ]
192then
6124aee5
NP
193 if test -z "$quiet"
194 then
195 echo >&2 "warning: You appear to be on a branch yet to be born."
196 echo >&2 "warning: Forcing checkout of $new_name."
197 fi
5a03e7f2
SP
198 force=1
199fi
200
a79944d7 201if [ "$force" ]
303e5f4c 202then
5be60078 203 git read-tree $v --reset -u $new
303e5f4c 204else
5be60078
JH
205 git update-index --refresh >/dev/null
206 merge_error=$(git read-tree -m -u --exclude-per-directory=.gitignore $old $new 2>&1) || (
1be0659e
JH
207 case "$merge" in
208 '')
209 echo >&2 "$merge_error"
210 exit 1 ;;
19205acf
JH
211 esac
212
1be0659e 213 # Match the index to the working tree, and do a three-way.
a6080a0a 214 git diff-files --name-only | git update-index --remove --stdin &&
19205acf 215 work=`git write-tree` &&
4c474b6f 216 git read-tree $v --reset -u $new || exit
1be0659e 217
41f5d733 218 eval GITHEAD_$new='${new_name:-${branch:-$new}}' &&
d7ebd53d
JH
219 eval GITHEAD_$work=local &&
220 export GITHEAD_$new GITHEAD_$work &&
221 git merge-recursive $old -- $new $work
1be0659e
JH
222
223 # Do not register the cleanly merged paths in the index yet.
224 # this is not a real merge before committing, but just carrying
225 # the working tree changes along.
226 unmerged=`git ls-files -u`
4c474b6f 227 git read-tree $v --reset $new
1be0659e
JH
228 case "$unmerged" in
229 '') ;;
230 *)
231 (
232 z40=0000000000000000000000000000000000000000
233 echo "$unmerged" |
234 sed -e 's/^[0-7]* [0-9a-f]* /'"0 $z40 /"
235 echo "$unmerged"
236 ) | git update-index --index-info
237 ;;
238 esac
239 exit 0
19205acf 240 )
980d8ce5 241 saved_err=$?
6124aee5 242 if test "$saved_err" = 0 && test -z "$quiet"
504fe714 243 then
e4b0e4ab 244 git diff-index --name-status "$new"
504fe714 245 fi
980d8ce5 246 (exit $saved_err)
ef0bfa25
LT
247fi
248
a6080a0a 249#
01385e27 250# Switch the HEAD pointer to the new branch if we
ef0bfa25
LT
251# checked out a branch head, and remove any potential
252# old MERGE_HEAD's (subsequent commits will clearly not
253# be based on them, since we re-set the index)
254#
255if [ "$?" -eq 0 ]; then
91dcdfd3 256 if [ "$newbranch" ]; then
5be60078 257 git branch $track $newbranch_log "$newbranch" "$new_name" || exit
91dcdfd3
LT
258 branch="$newbranch"
259 fi
bfbbb8f8
JH
260 if test -n "$branch"
261 then
49aba0bb
SE
262 old_branch_name=`expr "z$oldbranch" : 'zrefs/heads/\(.*\)'`
263 GIT_DIR="$GIT_DIR" git symbolic-ref -m "checkout: moving from $old_branch_name to $branch" HEAD "refs/heads/$branch"
57216856 264 if test -n "$quiet"
e4b0e4ab 265 then
57216856
NP
266 true # nothing
267 elif test "refs/heads/$branch" = "$oldbranch"
268 then
269 echo >&2 "Already on branch \"$branch\""
270 else
6124aee5 271 echo >&2 "Switched to${newbranch:+ a new} branch \"$branch\""
e4b0e4ab 272 fi
bfbbb8f8
JH
273 elif test -n "$detached"
274 then
5be60078 275 git update-ref --no-deref -m "checkout: moving to $arg" HEAD "$detached" ||
bfbbb8f8
JH
276 die "Cannot detach HEAD"
277 if test -n "$detach_warn"
278 then
279 echo >&2 "$detach_warn"
280 fi
abba9dbb 281 describe_detached_head 'HEAD is now at' HEAD
bfbbb8f8 282 fi
ef0bfa25 283 rm -f "$GIT_DIR/MERGE_HEAD"
ab22707f
TL
284else
285 exit 1
ef0bfa25 286fi