Teach git diff about BibTeX head hunk patterns
[git] / git-mergetool.sh
1 #!/bin/sh
2 #
3 # This program resolves merge conflicts in git
4 #
5 # Copyright (c) 2006 Theodore Y. Ts'o
6 #
7 # This file is licensed under the GPL v2, or a later version
8 # at the discretion of Junio C Hamano.
9 #
10
11 USAGE='[--tool=tool] [file to merge] ...'
12 SUBDIRECTORY_OK=Yes
13 OPTIONS_SPEC=
14 . git-sh-setup
15 require_work_tree
16 prefix=$(git rev-parse --show-prefix)
17
18 # Returns true if the mode reflects a symlink
19 is_symlink () {
20     test "$1" = 120000
21 }
22
23 local_present () {
24     test -n "$local_mode"
25 }
26
27 remote_present () {
28     test -n "$remote_mode"
29 }
30
31 base_present () {
32     test -n "$base_mode"
33 }
34
35 cleanup_temp_files () {
36     if test "$1" = --save-backup ; then
37         mv -- "$BACKUP" "$MERGED.orig"
38         rm -f -- "$LOCAL" "$REMOTE" "$BASE"
39     else
40         rm -f -- "$LOCAL" "$REMOTE" "$BASE" "$BACKUP"
41     fi
42 }
43
44 describe_file () {
45     mode="$1"
46     branch="$2"
47     file="$3"
48
49     printf "  {%s}: " "$branch"
50     if test -z "$mode"; then
51         echo "deleted"
52     elif is_symlink "$mode" ; then
53         echo "a symbolic link -> '$(cat "$file")'"
54     else
55         if base_present; then
56             echo "modified"
57         else
58             echo "created"
59         fi
60     fi
61 }
62
63
64 resolve_symlink_merge () {
65     while true; do
66         printf "Use (l)ocal or (r)emote, or (a)bort? "
67         read ans
68         case "$ans" in
69             [lL]*)
70                 git checkout-index -f --stage=2 -- "$MERGED"
71                 git add -- "$MERGED"
72                 cleanup_temp_files --save-backup
73                 return
74                 ;;
75             [rR]*)
76                 git checkout-index -f --stage=3 -- "$MERGED"
77                 git add -- "$MERGED"
78                 cleanup_temp_files --save-backup
79                 return
80                 ;;
81             [aA]*)
82                 exit 1
83                 ;;
84             esac
85         done
86 }
87
88 resolve_deleted_merge () {
89     while true; do
90         if base_present; then
91             printf "Use (m)odified or (d)eleted file, or (a)bort? "
92         else
93             printf "Use (c)reated or (d)eleted file, or (a)bort? "
94         fi
95         read ans
96         case "$ans" in
97             [mMcC]*)
98                 git add -- "$MERGED"
99                 cleanup_temp_files --save-backup
100                 return
101                 ;;
102             [dD]*)
103                 git rm -- "$MERGED" > /dev/null
104                 cleanup_temp_files
105                 return
106                 ;;
107             [aA]*)
108                 exit 1
109                 ;;
110             esac
111         done
112 }
113
114 check_unchanged () {
115     if test "$MERGED" -nt "$BACKUP" ; then
116         status=0;
117     else
118         while true; do
119             echo "$MERGED seems unchanged."
120             printf "Was the merge successful? [y/n] "
121             read answer < /dev/tty
122             case "$answer" in
123                 y*|Y*) status=0; break ;;
124                 n*|N*) status=1; break ;;
125             esac
126         done
127     fi
128 }
129
130 merge_file () {
131     MERGED="$1"
132
133     f=`git ls-files -u -- "$MERGED"`
134     if test -z "$f" ; then
135         if test ! -f "$MERGED" ; then
136             echo "$MERGED: file not found"
137         else
138             echo "$MERGED: file does not need merging"
139         fi
140         exit 1
141     fi
142
143     ext="$$$(expr "$MERGED" : '.*\(\.[^/]*\)$')"
144     BACKUP="./$MERGED.BACKUP.$ext"
145     LOCAL="./$MERGED.LOCAL.$ext"
146     REMOTE="./$MERGED.REMOTE.$ext"
147     BASE="./$MERGED.BASE.$ext"
148
149     mv -- "$MERGED" "$BACKUP"
150     cp -- "$BACKUP" "$MERGED"
151
152     base_mode=`git ls-files -u -- "$MERGED" | awk '{if ($3==1) print $1;}'`
153     local_mode=`git ls-files -u -- "$MERGED" | awk '{if ($3==2) print $1;}'`
154     remote_mode=`git ls-files -u -- "$MERGED" | awk '{if ($3==3) print $1;}'`
155
156     base_present   && git cat-file blob ":1:$prefix$MERGED" >"$BASE" 2>/dev/null
157     local_present  && git cat-file blob ":2:$prefix$MERGED" >"$LOCAL" 2>/dev/null
158     remote_present && git cat-file blob ":3:$prefix$MERGED" >"$REMOTE" 2>/dev/null
159
160     if test -z "$local_mode" -o -z "$remote_mode"; then
161         echo "Deleted merge conflict for '$MERGED':"
162         describe_file "$local_mode" "local" "$LOCAL"
163         describe_file "$remote_mode" "remote" "$REMOTE"
164         resolve_deleted_merge
165         return
166     fi
167
168     if is_symlink "$local_mode" || is_symlink "$remote_mode"; then
169         echo "Symbolic link merge conflict for '$MERGED':"
170         describe_file "$local_mode" "local" "$LOCAL"
171         describe_file "$remote_mode" "remote" "$REMOTE"
172         resolve_symlink_merge
173         return
174     fi
175
176     echo "Normal merge conflict for '$MERGED':"
177     describe_file "$local_mode" "local" "$LOCAL"
178     describe_file "$remote_mode" "remote" "$REMOTE"
179     printf "Hit return to start merge resolution tool (%s): " "$merge_tool"
180     read ans
181
182     case "$merge_tool" in
183         kdiff3)
184             if base_present ; then
185                 ("$merge_tool_path" --auto --L1 "$MERGED (Base)" --L2 "$MERGED (Local)" --L3 "$MERGED (Remote)" \
186                     -o "$MERGED" "$BASE" "$LOCAL" "$REMOTE" > /dev/null 2>&1)
187             else
188                 ("$merge_tool_path" --auto --L1 "$MERGED (Local)" --L2 "$MERGED (Remote)" \
189                     -o "$MERGED" "$LOCAL" "$REMOTE" > /dev/null 2>&1)
190             fi
191             status=$?
192             ;;
193         tkdiff)
194             if base_present ; then
195                 "$merge_tool_path" -a "$BASE" -o "$MERGED" "$LOCAL" "$REMOTE"
196             else
197                 "$merge_tool_path" -o "$MERGED" "$LOCAL" "$REMOTE"
198             fi
199             status=$?
200             ;;
201         meld|vimdiff)
202             touch "$BACKUP"
203             "$merge_tool_path" "$LOCAL" "$MERGED" "$REMOTE"
204             check_unchanged
205             ;;
206         gvimdiff)
207             touch "$BACKUP"
208             "$merge_tool_path" -f "$LOCAL" "$MERGED" "$REMOTE"
209             check_unchanged
210             ;;
211         xxdiff)
212             touch "$BACKUP"
213             if base_present ; then
214                 "$merge_tool_path" -X --show-merged-pane \
215                     -R 'Accel.SaveAsMerged: "Ctrl-S"' \
216                     -R 'Accel.Search: "Ctrl+F"' \
217                     -R 'Accel.SearchForward: "Ctrl-G"' \
218                     --merged-file "$MERGED" "$LOCAL" "$BASE" "$REMOTE"
219             else
220                 "$merge_tool_path" -X --show-merged-pane \
221                     -R 'Accel.SaveAsMerged: "Ctrl-S"' \
222                     -R 'Accel.Search: "Ctrl+F"' \
223                     -R 'Accel.SearchForward: "Ctrl-G"' \
224                     --merged-file "$MERGED" "$LOCAL" "$REMOTE"
225             fi
226             check_unchanged
227             ;;
228         opendiff)
229             touch "$BACKUP"
230             if base_present; then
231                 "$merge_tool_path" "$LOCAL" "$REMOTE" -ancestor "$BASE" -merge "$MERGED" | cat
232             else
233                 "$merge_tool_path" "$LOCAL" "$REMOTE" -merge "$MERGED" | cat
234             fi
235             check_unchanged
236             ;;
237         ecmerge)
238             touch "$BACKUP"
239             if base_present; then
240                 "$merge_tool_path" "$BASE" "$LOCAL" "$REMOTE" --default --mode=merge3 --to="$MERGED"
241             else
242                 "$merge_tool_path" "$LOCAL" "$REMOTE" --default --mode=merge2 --to="$MERGED"
243             fi
244             check_unchanged
245             ;;
246         emerge)
247             if base_present ; then
248                 "$merge_tool_path" -f emerge-files-with-ancestor-command "$LOCAL" "$REMOTE" "$BASE" "$(basename "$MERGED")"
249             else
250                 "$merge_tool_path" -f emerge-files-command "$LOCAL" "$REMOTE" "$(basename "$MERGED")"
251             fi
252             status=$?
253             ;;
254         *)
255             if test -n "$merge_tool_cmd"; then
256                 if test "$merge_tool_trust_exit_code" = "false"; then
257                     touch "$BACKUP"
258                     ( eval $merge_tool_cmd )
259                     check_unchanged
260                 else
261                     ( eval $merge_tool_cmd )
262                     status=$?
263                 fi
264             fi
265             ;;
266     esac
267     if test "$status" -ne 0; then
268         echo "merge of $MERGED failed" 1>&2
269         mv -- "$BACKUP" "$MERGED"
270         exit 1
271     fi
272
273     if test "$merge_keep_backup" = "true"; then
274         mv -- "$BACKUP" "$MERGED.orig"
275     else
276         rm -- "$BACKUP"
277     fi
278
279     git add -- "$MERGED"
280     cleanup_temp_files
281 }
282
283 while test $# != 0
284 do
285     case "$1" in
286         -t|--tool*)
287             case "$#,$1" in
288                 *,*=*)
289                     merge_tool=`expr "z$1" : 'z-[^=]*=\(.*\)'`
290                     ;;
291                 1,*)
292                     usage ;;
293                 *)
294                     merge_tool="$2"
295                     shift ;;
296             esac
297             ;;
298         --)
299             break
300             ;;
301         -*)
302             usage
303             ;;
304         *)
305             break
306             ;;
307     esac
308     shift
309 done
310
311 valid_custom_tool()
312 {
313     merge_tool_cmd="$(git config mergetool.$1.cmd)"
314     test -n "$merge_tool_cmd"
315 }
316
317 valid_tool() {
318         case "$1" in
319                 kdiff3 | tkdiff | xxdiff | meld | opendiff | emerge | vimdiff | gvimdiff | ecmerge)
320                         ;; # happy
321                 *)
322                         if ! valid_custom_tool "$1"; then
323                                 return 1
324                         fi
325                         ;;
326         esac
327 }
328
329 init_merge_tool_path() {
330         merge_tool_path=`git config mergetool.$1.path`
331         if test -z "$merge_tool_path" ; then
332                 case "$1" in
333                         emerge)
334                                 merge_tool_path=emacs
335                                 ;;
336                         *)
337                                 merge_tool_path=$1
338                                 ;;
339                 esac
340         fi
341 }
342
343
344 if test -z "$merge_tool"; then
345     merge_tool=`git config merge.tool`
346     if test -n "$merge_tool" && ! valid_tool "$merge_tool"; then
347             echo >&2 "git config option merge.tool set to unknown tool: $merge_tool"
348             echo >&2 "Resetting to default..."
349             unset merge_tool
350     fi
351 fi
352
353 if test -z "$merge_tool" ; then
354     if test -n "$DISPLAY"; then
355         merge_tool_candidates="kdiff3 tkdiff xxdiff meld gvimdiff"
356         if test -n "$GNOME_DESKTOP_SESSION_ID" ; then
357             merge_tool_candidates="meld $merge_tool_candidates"
358         fi
359         if test "$KDE_FULL_SESSION" = "true"; then
360             merge_tool_candidates="kdiff3 $merge_tool_candidates"
361         fi
362     fi
363     if echo "${VISUAL:-$EDITOR}" | grep 'emacs' > /dev/null 2>&1; then
364         merge_tool_candidates="$merge_tool_candidates emerge"
365     fi
366     if echo "${VISUAL:-$EDITOR}" | grep 'vim' > /dev/null 2>&1; then
367         merge_tool_candidates="$merge_tool_candidates vimdiff"
368     fi
369     merge_tool_candidates="$merge_tool_candidates opendiff emerge vimdiff"
370     echo "merge tool candidates: $merge_tool_candidates"
371     for i in $merge_tool_candidates; do
372         init_merge_tool_path $i
373         if type "$merge_tool_path" > /dev/null 2>&1; then
374             merge_tool=$i
375             break
376         fi
377     done
378     if test -z "$merge_tool" ; then
379         echo "No known merge resolution program available."
380         exit 1
381     fi
382 else
383     if ! valid_tool "$merge_tool"; then
384         echo >&2 "Unknown merge_tool $merge_tool"
385         exit 1
386     fi
387
388     init_merge_tool_path "$merge_tool"
389
390     merge_keep_backup="$(git config --bool merge.keepBackup || echo true)"
391
392     if test -z "$merge_tool_cmd" && ! type "$merge_tool_path" > /dev/null 2>&1; then
393         echo "The merge tool $merge_tool is not available as '$merge_tool_path'"
394         exit 1
395     fi
396
397     if ! test -z "$merge_tool_cmd"; then
398         merge_tool_trust_exit_code="$(git config --bool mergetool.$merge_tool.trustExitCode || echo false)"
399     fi
400 fi
401
402
403 if test $# -eq 0 ; then
404         files=`git ls-files -u | sed -e 's/^[^  ]*      //' | sort -u`
405         if test -z "$files" ; then
406                 echo "No files need merging"
407                 exit 0
408         fi
409         echo Merging the files: "$files"
410         git ls-files -u |
411         sed -e 's/^[^   ]*      //' |
412         sort -u |
413         while IFS= read i
414         do
415                 printf "\n"
416                 merge_file "$i" < /dev/tty > /dev/tty
417         done
418 else
419         while test $# -gt 0; do
420                 printf "\n"
421                 merge_file "$1"
422                 shift
423         done
424 fi
425 exit 0