Keep bisection log so that it can be replayed later.
[git.git] / git-bisect.sh
1 #!/bin/sh
2 . git-sh-setup || dir "Not a git archive"
3
4 usage() {
5     echo >&2 'usage: git bisect [start|bad|good|next|reset|visualize]
6 git bisect start                reset bisect state and start bisection.
7 git bisect bad [<rev>]          mark <rev> a known-bad revision.
8 git bisect good [<rev>...]      mark <rev>... known-good revisions.
9 git bisect next                 find next bisection to test and check it out.
10 git bisect reset [<branch>]     finish bisection search and go back to branch.
11 git bisect visualize            show bisect status in gitk.
12 git bisect replay <logfile>     replay bisection log
13 git bisect log                  show bisect log.'
14     exit 1
15 }
16
17 bisect_autostart() {
18         test -d "$GIT_DIR/refs/bisect" || {
19                 echo >&2 'You need to start by "git bisect start"'
20                 if test -t 0
21                 then
22                         echo >&2 -n 'Do you want me to do it for you [Y/n]? '
23                         read yesno
24                         case "$yesno" in
25                         [Nn]*)
26                                 exit ;;
27                         esac
28                         bisect_start
29                 else
30                         exit 1
31                 fi
32         }
33 }
34
35 bisect_start() {
36         case "$#" in 0) ;; *) usage ;; esac
37         #
38         # Verify HEAD. If we were bisecting before this, reset to the
39         # top-of-line master first!
40         #
41         head=$(readlink $GIT_DIR/HEAD) || die "Bad HEAD - I need a symlink"
42         case "$head" in
43         refs/heads/bisect*)
44                 git checkout master || exit
45                 ;;
46         refs/heads/*)
47                 ;;
48         *)
49                 die "Bad HEAD - strange symlink"
50                 ;;
51         esac
52
53         #
54         # Get rid of any old bisect state
55         #
56         rm -f "$GIT_DIR/refs/heads/bisect"
57         rm -rf "$GIT_DIR/refs/bisect/"
58         mkdir "$GIT_DIR/refs/bisect"
59         echo "git-bisect start" >"$GIT_DIR/BISECT_LOG"
60 }
61
62 bisect_bad() {
63         bisect_autostart
64         case "$#" in
65         0)
66                 rev=$(git-rev-parse --verify HEAD) ;;
67         1)
68                 rev=$(git-rev-parse --verify "$1") ;;
69         *)
70                 usage ;;
71         esac || exit
72         echo "$rev" >"$GIT_DIR/refs/bisect/bad"
73         echo "# bad: "$(git-show-branch $rev) >>"$GIT_DIR/BISECT_LOG"
74         echo "git-bisect bad $rev" >>"$GIT_DIR/BISECT_LOG"
75         bisect_auto_next
76 }
77
78 bisect_good() {
79         bisect_autostart
80         case "$#" in
81         0)    revs=$(git-rev-parse --verify HEAD) || exit ;;
82         *)    revs=$(git-rev-parse --revs-only --no-flags "$@") &&
83                 test '' != "$revs" || die "Bad rev input: $@" ;;
84         esac
85         for rev in $revs
86         do
87                 rev=$(git-rev-parse --verify "$rev") || exit
88                 echo "$rev" >"$GIT_DIR/refs/bisect/good-$rev"
89                 echo "# good: "$(git-show-branch $rev) >>"$GIT_DIR/BISECT_LOG"
90                 echo "git-bisect good $rev" >>"$GIT_DIR/BISECT_LOG"
91         done
92         bisect_auto_next
93 }
94
95 bisect_next_check() {
96         next_ok=no
97         test -f "$GIT_DIR/refs/bisect/bad" &&
98         case "$(cd "$GIT_DIR" && echo refs/bisect/good-*)" in
99         refs/bisect/good-\*) ;;
100         *) next_ok=yes ;;
101         esac
102         case "$next_ok,$1" in
103         no,) false ;;
104         no,fail)
105             echo >&2 'You need to give me at least one good and one bad revisions.'
106             exit 1 ;;
107         *)
108             true ;;
109         esac
110 }
111
112 bisect_auto_next() {
113         bisect_next_check && bisect_next
114 }
115
116 bisect_next() {
117         case "$#" in 0) ;; *) usage ;; esac
118         bisect_autostart
119         bisect_next_check fail
120         bad=$(git-rev-parse --verify refs/bisect/bad) &&
121         good=$(git-rev-parse --sq --revs-only --not \
122                 $(cd "$GIT_DIR" && ls refs/bisect/good-*)) &&
123         rev=$(eval "git-rev-list --bisect $good $bad") || exit
124         if [ -z "$rev" ]; then
125             echo "$bad was both good and bad"
126             exit 1
127         fi
128         if [ "$rev" = "$bad" ]; then
129             echo "$rev is first bad commit"
130             git-diff-tree --pretty $rev
131             exit 0
132         fi
133         nr=$(eval "git-rev-list $rev $good" | wc -l) || exit
134         echo "Bisecting: $nr revisions left to test after this"
135         echo "$rev" > "$GIT_DIR/refs/heads/new-bisect"
136         git checkout new-bisect || exit
137         mv "$GIT_DIR/refs/heads/new-bisect" "$GIT_DIR/refs/heads/bisect" &&
138         ln -sf refs/heads/bisect "$GIT_DIR/HEAD"
139         git-show-branch "$rev"
140 }
141
142 bisect_visualize() {
143         bisect_next_check fail
144         gitk bisect/bad --not `cd "$GIT_DIR/refs" && echo bisect/good-*`
145 }
146
147 bisect_reset() {
148         case "$#" in
149         0) branch=master ;;
150         1) test -f "$GIT_DIR/refs/heads/$1" || {
151                echo >&2 "$1 does not seem to be a valid branch"
152                exit 1
153            }
154            branch="$1" ;;
155         *)
156             usage ;;
157         esac
158         git checkout "$branch" &&
159         rm -fr "$GIT_DIR/refs/bisect"
160         rm -f "$GIT_DIR/refs/heads/bisect"
161         rm -f "$GIT_DIR/BISECT_LOG"
162 }
163
164 bisect_replay () {
165         test -r "$1" || {
166                 echo >&2 "cannot read $1 for replaying"
167                 exit 1
168         }
169         bisect_reset
170         while read bisect command rev
171         do
172                 test "$bisect" = "git-bisect" || continue
173                 case "$command" in
174                 start)
175                         bisect_start
176                         ;;
177                 good)
178                         echo "$rev" >"$GIT_DIR/refs/bisect/good-$rev"
179                         echo "# good: "$(git-show-branch $rev) >>"$GIT_DIR/BISECT_LOG"
180                         echo "git-bisect good $rev" >>"$GIT_DIR/BISECT_LOG"
181                         ;;
182                 bad)
183                         echo "$rev" >"$GIT_DIR/refs/bisect/bad"
184                         echo "# bad: "$(git-show-branch $rev) >>"$GIT_DIR/BISECT_LOG"
185                         echo "git-bisect bad $rev" >>"$GIT_DIR/BISECT_LOG"
186                         ;;
187                 *)
188                         echo >&2 "?? what are you talking about?"
189                         exit 1 ;;
190                 esac
191         done <"$1"
192         bisect_auto_next
193 }
194
195 case "$#" in
196 0)
197     usage ;;
198 *)
199     cmd="$1"
200     shift
201     case "$cmd" in
202     start)
203         bisect_start "$@" ;;
204     bad)
205         bisect_bad "$@" ;;
206     good)
207         bisect_good "$@" ;;
208     next)
209         # Not sure we want "next" at the UI level anymore.
210         bisect_next "$@" ;;
211     visualize)
212         bisect_visualize "$@" ;;
213     reset)
214         bisect_reset "$@" ;;
215     replay)
216         bisect_replay "$@" ;;
217     log)
218         cat "$GIT_DIR/BISECT_LOG" ;;
219     *)
220         usage ;;
221     esac
222 esac