Documentation/SubmittingPatches: Gnus tips
[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] [-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 . git-sh-setup
11 set_reflog_action "pull $*"
12 require_work_tree
13 cd_to_toplevel
14
15 test -z "$(git ls-files -u)" ||
16         die "You are in the middle of a conflicted merge."
17
18 strategy_args= no_summary= no_commit= squash=
19 while case "$#,$1" in 0) break ;; *,-*) ;; *) break ;; esac
20 do
21         case "$1" in
22         -n|--n|--no|--no-|--no-s|--no-su|--no-sum|--no-summ|\
23                 --no-summa|--no-summar|--no-summary)
24                 no_summary=-n ;;
25         --no-c|--no-co|--no-com|--no-comm|--no-commi|--no-commit)
26                 no_commit=--no-commit ;;
27         --sq|--squ|--squa|--squas|--squash)
28                 squash=--squash ;;
29         -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
30                 --strateg=*|--strategy=*|\
31         -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
32                 case "$#,$1" in
33                 *,*=*)
34                         strategy=`expr "z$1" : 'z-[^=]*=\(.*\)'` ;;
35                 1,*)
36                         usage ;;
37                 *)
38                         strategy="$2"
39                         shift ;;
40                 esac
41                 strategy_args="${strategy_args}-s $strategy "
42                 ;;
43         -h|--h|--he|--hel|--help)
44                 usage
45                 ;;
46         -*)
47                 # Pass thru anything that is meant for fetch.
48                 break
49                 ;;
50         esac
51         shift
52 done
53
54 orig_head=$(git-rev-parse --verify HEAD 2>/dev/null)
55 git-fetch --update-head-ok "$@" || exit 1
56
57 curr_head=$(git-rev-parse --verify HEAD 2>/dev/null)
58 if test "$curr_head" != "$orig_head"
59 then
60         # The fetch involved updating the current branch.
61
62         # The working tree and the index file is still based on the
63         # $orig_head commit, but we are merging into $curr_head.
64         # First update the working tree to match $curr_head.
65
66         echo >&2 "Warning: fetch updated the current branch head."
67         echo >&2 "Warning: fast forwarding your working tree from"
68         echo >&2 "Warning: commit $orig_head."
69         git-update-index --refresh 2>/dev/null
70         git-read-tree -u -m "$orig_head" "$curr_head" ||
71                 die 'Cannot fast-forward your working tree.
72 After making sure that you saved anything precious from
73 $ git diff '$orig_head'
74 output, run
75 $ git reset --hard
76 to recover.'
77
78 fi
79
80 merge_head=$(sed -e '/  not-for-merge   /d' \
81         -e 's/  .*//' "$GIT_DIR"/FETCH_HEAD | \
82         tr '\012' ' ')
83
84 case "$merge_head" in
85 '')
86         curr_branch=$(git-symbolic-ref -q HEAD)
87         case $? in
88           0) ;;
89           1) echo >&2 "You are not currently on a branch; you must explicitly"
90              echo >&2 "specify which branch you wish to merge:"
91              echo >&2 "  git pull <remote> <branch>"
92              exit 1;;
93           *) exit $?;;
94         esac
95         curr_branch=${curr_branch#refs/heads/}
96
97         echo >&2 "Warning: No merge candidate found because value of config option
98          \"branch.${curr_branch}.merge\" does not match any remote branch fetched."
99         echo >&2 "No changes."
100         exit 0
101         ;;
102 ?*' '?*)
103         if test -z "$orig_head"
104         then
105                 echo >&2 "Cannot merge multiple branches into empty head"
106                 exit 1
107         fi
108         ;;
109 esac
110
111 if test -z "$orig_head"
112 then
113         git-update-ref -m "initial pull" HEAD $merge_head "" &&
114         git-read-tree --reset -u HEAD || exit 1
115         exit
116 fi
117
118 merge_name=$(git-fmt-merge-msg <"$GIT_DIR/FETCH_HEAD") || exit
119 exec git-merge $no_summary $no_commit $squash $strategy_args \
120         "$merge_name" HEAD $merge_head