"git pull --tags": error out with a better message.
[git] / git-pull.sh
1 #!/bin/sh
2 #
3 # Copyright (c) 2005 Junio C Hamano
4 #
5 # Fetch one or more remote refs and merge it/them into the current HEAD.
6
7 USAGE='[-n | --no-summary] [--[no-]commit] [--[no-]squash] [--[no-]ff] [-s strategy]... [<fetch-options>] <repo> <head>...'
8 LONG_USAGE='Fetch one or more remote refs and merge it/them into the current HEAD.'
9 SUBDIRECTORY_OK=Yes
10 OPTIONS_SPEC=
11 . git-sh-setup
12 set_reflog_action "pull $*"
13 require_work_tree
14 cd_to_toplevel
15
16 test -z "$(git ls-files -u)" ||
17         die "You are in the middle of a conflicted merge."
18
19 strategy_args= no_summary= no_commit= squash= no_ff=
20 curr_branch=$(git symbolic-ref -q HEAD)
21 curr_branch_short=$(echo "$curr_branch" | sed "s|refs/heads/||")
22 rebase=$(git config --bool branch.$curr_branch_short.rebase)
23 while :
24 do
25         case "$1" in
26         -n|--n|--no|--no-|--no-s|--no-su|--no-sum|--no-summ|\
27                 --no-summa|--no-summar|--no-summary)
28                 no_summary=-n ;;
29         --summary)
30                 no_summary=$1
31                 ;;
32         --no-c|--no-co|--no-com|--no-comm|--no-commi|--no-commit)
33                 no_commit=--no-commit ;;
34         --c|--co|--com|--comm|--commi|--commit)
35                 no_commit=--commit ;;
36         --sq|--squ|--squa|--squas|--squash)
37                 squash=--squash ;;
38         --no-sq|--no-squ|--no-squa|--no-squas|--no-squash)
39                 squash=--no-squash ;;
40         --ff)
41                 no_ff=--ff ;;
42         --no-ff)
43                 no_ff=--no-ff ;;
44         -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
45                 --strateg=*|--strategy=*|\
46         -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
47                 case "$#,$1" in
48                 *,*=*)
49                         strategy=`expr "z$1" : 'z-[^=]*=\(.*\)'` ;;
50                 1,*)
51                         usage ;;
52                 *)
53                         strategy="$2"
54                         shift ;;
55                 esac
56                 strategy_args="${strategy_args}-s $strategy "
57                 ;;
58         -r|--r|--re|--reb|--reba|--rebas|--rebase)
59                 rebase=true
60                 ;;
61         --no-r|--no-re|--no-reb|--no-reba|--no-rebas|--no-rebase)
62                 rebase=false
63                 ;;
64         -h|--h|--he|--hel|--help)
65                 usage
66                 ;;
67         *)
68                 # Pass thru anything that may be meant for fetch.
69                 break
70                 ;;
71         esac
72         shift
73 done
74
75 error_on_no_merge_candidates () {
76         exec >&2
77         for opt
78         do
79                 case "$opt" in
80                 -t|--t|--ta|--tag|--tags)
81                         echo "Fetching tags only, you probably meant:"
82                         echo "  git fetch --tags"
83                         exit 1
84                 esac
85         done
86
87         curr_branch=${curr_branch#refs/heads/}
88
89         echo "You asked me to pull without telling me which branch you"
90         echo "want to merge with, and 'branch.${curr_branch}.merge' in"
91         echo "your configuration file does not tell me either.  Please"
92         echo "name which branch you want to merge on the command line and"
93         echo "try again (e.g. 'git pull <repository> <refspec>')."
94         echo "See git-pull(1) for details on the refspec."
95         echo
96         echo "If you often merge with the same branch, you may want to"
97         echo "configure the following variables in your configuration"
98         echo "file:"
99         echo
100         echo "    branch.${curr_branch}.remote = <nickname>"
101         echo "    branch.${curr_branch}.merge = <remote-ref>"
102         echo "    remote.<nickname>.url = <url>"
103         echo "    remote.<nickname>.fetch = <refspec>"
104         echo
105         echo "See git-config(1) for details."
106         exit 1
107 }
108
109 orig_head=$(git rev-parse --verify HEAD 2>/dev/null)
110 git-fetch --update-head-ok "$@" || exit 1
111
112 curr_head=$(git rev-parse --verify HEAD 2>/dev/null)
113 if test "$curr_head" != "$orig_head"
114 then
115         # The fetch involved updating the current branch.
116
117         # The working tree and the index file is still based on the
118         # $orig_head commit, but we are merging into $curr_head.
119         # First update the working tree to match $curr_head.
120
121         echo >&2 "Warning: fetch updated the current branch head."
122         echo >&2 "Warning: fast forwarding your working tree from"
123         echo >&2 "Warning: commit $orig_head."
124         git update-index --refresh 2>/dev/null
125         git read-tree -u -m "$orig_head" "$curr_head" ||
126                 die 'Cannot fast-forward your working tree.
127 After making sure that you saved anything precious from
128 $ git diff '$orig_head'
129 output, run
130 $ git reset --hard
131 to recover.'
132
133 fi
134
135 merge_head=$(sed -e '/  not-for-merge   /d' \
136         -e 's/  .*//' "$GIT_DIR"/FETCH_HEAD | \
137         tr '\012' ' ')
138
139 case "$merge_head" in
140 '')
141         case $? in
142         0) error_on_no_merge_candidates "$@";;
143         1) echo >&2 "You are not currently on a branch; you must explicitly"
144            echo >&2 "specify which branch you wish to merge:"
145            echo >&2 "  git pull <remote> <branch>"
146            exit 1;;
147         *) exit $?;;
148         esac
149         ;;
150 ?*' '?*)
151         if test -z "$orig_head"
152         then
153                 echo >&2 "Cannot merge multiple branches into empty head"
154                 exit 1
155         fi
156         ;;
157 esac
158
159 if test -z "$orig_head"
160 then
161         git update-ref -m "initial pull" HEAD $merge_head "" &&
162         git read-tree --reset -u HEAD || exit 1
163         exit
164 fi
165
166 merge_name=$(git fmt-merge-msg <"$GIT_DIR/FETCH_HEAD") || exit
167 test true = "$rebase" && exec git-rebase $merge_head
168 exec git-merge $no_summary $no_commit $squash $no_ff $strategy_args \
169         "$merge_name" HEAD $merge_head