Merge branch 'fix'
[git/git.git] / git-rebase.sh
1 #!/bin/sh
2 #
3 # Copyright (c) 2005 Junio C Hamano.
4 #
5
6 USAGE='[--onto <newbase>] <upstream> [<branch>]'
7 LONG_USAGE='git-rebase replaces <branch> with a new branch of the
8 same name. When the --onto option is provided the new branch starts
9 out with a HEAD equal to <newbase>, otherwise it is equal to <upstream>
10 It then attempts to create a new commit for each commit from the original
11 <branch> that does not exist in the <upstream> branch.
12
13 It is possible that a merge failure will prevent this process from being
14 completely automatic. You will have to resolve any such merge failure
15 and run git-rebase --continue. If you can not resolve the merge failure,
16 running git-rebase --abort will restore the original <branch> and remove
17 the working files found in the .dotest directory.
18
19 Note that if <branch> is not specified on the command line, the
20 currently checked out branch is used. You must be in the top
21 directory of your project to start (or continue) a rebase.
22
23 Example: git-rebase master~1 topic
24
25 A---B---C topic A'\''--B'\''--C'\'' topic
26 / --> /
27 D---E---F---G master D---E---F---G master
28 '
29 . git-sh-setup
30
31 unset newbase
32 while case "$#" in 0) break ;; esac
33 do
34 case "$1" in
35 --continue)
36 diff=$(git-diff-files)
37 case "$diff" in
38 ?*) echo "You must edit all merge conflicts and then"
39 echo "mark them as resolved using git update-index"
40 exit 1
41 ;;
42 esac
43 git am --resolved --3way
44 exit
45 ;;
46 --abort)
47 [ -d .dotest ] || die "No rebase in progress?"
48 git reset --hard ORIG_HEAD
49 rm -r .dotest
50 exit
51 ;;
52 --onto)
53 test 2 -le "$#" || usage
54 newbase="$2"
55 shift
56 ;;
57 -*)
58 usage
59 ;;
60 *)
61 break
62 ;;
63 esac
64 shift
65 done
66
67 # Make sure we do not have .dotest
68 if mkdir .dotest
69 then
70 rmdir .dotest
71 else
72 echo >&2 '
73 It seems that I cannot create a .dotest directory, and I wonder if you
74 are in the middle of patch application or another rebase. If that is not
75 the case, please rm -fr .dotest and run me again. I am stopping in case
76 you still have something valuable there.'
77 exit 1
78 fi
79
80 # The tree must be really really clean.
81 git-update-index --refresh || exit
82 diff=$(git-diff-index --cached --name-status -r HEAD)
83 case "$diff" in
84 ?*) echo "$diff"
85 exit 1
86 ;;
87 esac
88
89 # The upstream head must be given. Make sure it is valid.
90 upstream_name="$1"
91 upstream=`git rev-parse --verify "${upstream_name}^0"` ||
92 die "invalid upstream $upstream_name"
93
94 # If a hook exists, give it a chance to interrupt
95 if test -x "$GIT_DIR/hooks/pre-rebase"
96 then
97 "$GIT_DIR/hooks/pre-rebase" ${1+"$@"} || {
98 echo >&2 "The pre-rebase hook refused to rebase."
99 exit 1
100 }
101 fi
102
103 # If the branch to rebase is given, first switch to it.
104 case "$#" in
105 2)
106 branch_name="$2"
107 git-checkout "$2" || usage
108 ;;
109 *)
110 branch_name=`git symbolic-ref HEAD` || die "No current branch"
111 branch_name=`expr "z$branch_name" : 'zrefs/heads/\(.*\)'`
112 ;;
113 esac
114 branch=$(git-rev-parse --verify "${branch_name}^0") || exit
115
116 # Make sure the branch to rebase onto is valid.
117 onto_name=${newbase-"$upstream_name"}
118 onto=$(git-rev-parse --verify "${onto_name}^0") || exit
119
120 # Now we are rebasing commits $upstream..$branch on top of $onto
121
122 # Check if we are already based on $onto, but this should be
123 # done only when upstream and onto are the same.
124 if test "$upstream" = "$onto"
125 then
126 mb=$(git-merge-base "$onto" "$branch")
127 if test "$mb" = "$onto"
128 then
129 echo >&2 "Current branch $branch_name is up to date."
130 exit 0
131 fi
132 fi
133
134 # Rewind the head to "$onto"; this saves our current head in ORIG_HEAD.
135 git-reset --hard "$onto"
136
137 # If the $onto is a proper descendant of the tip of the branch, then
138 # we just fast forwarded.
139 if test "$mb" = "$onto"
140 then
141 echo >&2 "Fast-forwarded $branch to $newbase."
142 exit 0
143 fi
144
145 git-format-patch -k --stdout --full-index "$upstream" ORIG_HEAD |
146 git am --binary -3 -k