Merge git://repo.or.cz/git-gui
[git/git.git] / git-gui / lib / diff.tcl
1 # git-gui diff viewer
2 # Copyright (C) 2006, 2007 Shawn Pearce
3
4 proc clear_diff {} {
5 global ui_diff current_diff_path current_diff_header
6 global ui_index ui_workdir
7
8 $ui_diff conf -state normal
9 $ui_diff delete 0.0 end
10 $ui_diff conf -state disabled
11
12 set current_diff_path {}
13 set current_diff_header {}
14
15 $ui_index tag remove in_diff 0.0 end
16 $ui_workdir tag remove in_diff 0.0 end
17 }
18
19 proc reshow_diff {} {
20 global file_states file_lists
21 global current_diff_path current_diff_side
22 global ui_diff
23
24 set p $current_diff_path
25 if {$p eq {}} {
26 # No diff is being shown.
27 } elseif {$current_diff_side eq {}} {
28 clear_diff
29 } elseif {[catch {set s $file_states($p)}]
30 || [lsearch -sorted -exact $file_lists($current_diff_side) $p] == -1} {
31
32 if {[find_next_diff $current_diff_side $p {} {[^O]}]} {
33 next_diff
34 } else {
35 clear_diff
36 }
37 } else {
38 set save_pos [lindex [$ui_diff yview] 0]
39 show_diff $p $current_diff_side {} $save_pos
40 }
41 }
42
43 proc force_diff_encoding {enc} {
44 global current_diff_path
45
46 if {$current_diff_path ne {}} {
47 force_path_encoding $current_diff_path $enc
48 reshow_diff
49 }
50 }
51
52 proc handle_empty_diff {} {
53 global current_diff_path file_states file_lists
54
55 set path $current_diff_path
56 set s $file_states($path)
57 if {[lindex $s 0] ne {_M}} return
58
59 info_popup [mc "No differences detected.
60
61 %s has no changes.
62
63 The modification date of this file was updated by another application, but the content within the file was not changed.
64
65 A rescan will be automatically started to find other files which may have the same state." [short_path $path]]
66
67 clear_diff
68 display_file $path __
69 rescan ui_ready 0
70 }
71
72 proc show_diff {path w {lno {}} {scroll_pos {}} {callback {}}} {
73 global file_states file_lists
74 global is_3way_diff is_conflict_diff diff_active repo_config
75 global ui_diff ui_index ui_workdir
76 global current_diff_path current_diff_side current_diff_header
77 global current_diff_queue
78
79 if {$diff_active || ![lock_index read]} return
80
81 clear_diff
82 if {$lno == {}} {
83 set lno [lsearch -sorted -exact $file_lists($w) $path]
84 if {$lno >= 0} {
85 incr lno
86 }
87 }
88 if {$lno >= 1} {
89 $w tag add in_diff $lno.0 [expr {$lno + 1}].0
90 $w see $lno.0
91 }
92
93 set s $file_states($path)
94 set m [lindex $s 0]
95 set is_conflict_diff 0
96 set current_diff_path $path
97 set current_diff_side $w
98 set current_diff_queue {}
99 ui_status [mc "Loading diff of %s..." [escape_path $path]]
100
101 set cont_info [list $scroll_pos $callback]
102
103 if {[string first {U} $m] >= 0} {
104 merge_load_stages $path [list show_unmerged_diff $cont_info]
105 } elseif {$m eq {_O}} {
106 show_other_diff $path $w $m $cont_info
107 } else {
108 start_show_diff $cont_info
109 }
110 }
111
112 proc show_unmerged_diff {cont_info} {
113 global current_diff_path current_diff_side
114 global merge_stages ui_diff is_conflict_diff
115 global current_diff_queue
116
117 if {$merge_stages(2) eq {}} {
118 set is_conflict_diff 1
119 lappend current_diff_queue \
120 [list "LOCAL: deleted\nREMOTE:\n" d======= \
121 [list ":1:$current_diff_path" ":3:$current_diff_path"]]
122 } elseif {$merge_stages(3) eq {}} {
123 set is_conflict_diff 1
124 lappend current_diff_queue \
125 [list "REMOTE: deleted\nLOCAL:\n" d======= \
126 [list ":1:$current_diff_path" ":2:$current_diff_path"]]
127 } elseif {[lindex $merge_stages(1) 0] eq {120000}
128 || [lindex $merge_stages(2) 0] eq {120000}
129 || [lindex $merge_stages(3) 0] eq {120000}} {
130 set is_conflict_diff 1
131 lappend current_diff_queue \
132 [list "LOCAL:\n" d======= \
133 [list ":1:$current_diff_path" ":2:$current_diff_path"]]
134 lappend current_diff_queue \
135 [list "REMOTE:\n" d======= \
136 [list ":1:$current_diff_path" ":3:$current_diff_path"]]
137 } else {
138 start_show_diff $cont_info
139 return
140 }
141
142 advance_diff_queue $cont_info
143 }
144
145 proc advance_diff_queue {cont_info} {
146 global current_diff_queue ui_diff
147
148 set item [lindex $current_diff_queue 0]
149 set current_diff_queue [lrange $current_diff_queue 1 end]
150
151 $ui_diff conf -state normal
152 $ui_diff insert end [lindex $item 0] [lindex $item 1]
153 $ui_diff conf -state disabled
154
155 start_show_diff $cont_info [lindex $item 2]
156 }
157
158 proc show_other_diff {path w m cont_info} {
159 global file_states file_lists
160 global is_3way_diff diff_active repo_config
161 global ui_diff ui_index ui_workdir
162 global current_diff_path current_diff_side current_diff_header
163
164 # - Git won't give us the diff, there's nothing to compare to!
165 #
166 if {$m eq {_O}} {
167 set max_sz [expr {128 * 1024}]
168 set type unknown
169 if {[catch {
170 set type [file type $path]
171 switch -- $type {
172 directory {
173 set type submodule
174 set content {}
175 set sz 0
176 }
177 link {
178 set content [file readlink $path]
179 set sz [string length $content]
180 }
181 file {
182 set fd [open $path r]
183 fconfigure $fd \
184 -eofchar {} \
185 -encoding [get_path_encoding $path]
186 set content [read $fd $max_sz]
187 close $fd
188 set sz [file size $path]
189 }
190 default {
191 error "'$type' not supported"
192 }
193 }
194 } err ]} {
195 set diff_active 0
196 unlock_index
197 ui_status [mc "Unable to display %s" [escape_path $path]]
198 error_popup [strcat [mc "Error loading file:"] "\n\n$err"]
199 return
200 }
201 $ui_diff conf -state normal
202 if {$type eq {submodule}} {
203 $ui_diff insert end [append \
204 "* " \
205 [mc "Git Repository (subproject)"] \
206 "\n"] d_@
207 } elseif {![catch {set type [exec file $path]}]} {
208 set n [string length $path]
209 if {[string equal -length $n $path $type]} {
210 set type [string range $type $n end]
211 regsub {^:?\s*} $type {} type
212 }
213 $ui_diff insert end "* $type\n" d_@
214 }
215 if {[string first "\0" $content] != -1} {
216 $ui_diff insert end \
217 [mc "* Binary file (not showing content)."] \
218 d_@
219 } else {
220 if {$sz > $max_sz} {
221 $ui_diff insert end \
222 "* Untracked file is $sz bytes.
223 * Showing only first $max_sz bytes.
224 " d_@
225 }
226 $ui_diff insert end $content
227 if {$sz > $max_sz} {
228 $ui_diff insert end "
229 * Untracked file clipped here by [appname].
230 * To see the entire file, use an external editor.
231 " d_@
232 }
233 }
234 $ui_diff conf -state disabled
235 set diff_active 0
236 unlock_index
237 set scroll_pos [lindex $cont_info 0]
238 if {$scroll_pos ne {}} {
239 update
240 $ui_diff yview moveto $scroll_pos
241 }
242 ui_ready
243 set callback [lindex $cont_info 1]
244 if {$callback ne {}} {
245 eval $callback
246 }
247 return
248 }
249 }
250
251 proc start_show_diff {cont_info {add_opts {}}} {
252 global file_states file_lists
253 global is_3way_diff diff_active repo_config
254 global ui_diff ui_index ui_workdir
255 global current_diff_path current_diff_side current_diff_header
256
257 set path $current_diff_path
258 set w $current_diff_side
259
260 set s $file_states($path)
261 set m [lindex $s 0]
262 set is_3way_diff 0
263 set diff_active 1
264 set current_diff_header {}
265
266 set cmd [list]
267 if {$w eq $ui_index} {
268 lappend cmd diff-index
269 lappend cmd --cached
270 } elseif {$w eq $ui_workdir} {
271 if {[string first {U} $m] >= 0} {
272 lappend cmd diff
273 } else {
274 lappend cmd diff-files
275 }
276 }
277
278 lappend cmd -p
279 lappend cmd --no-color
280 if {$repo_config(gui.diffcontext) >= 1} {
281 lappend cmd "-U$repo_config(gui.diffcontext)"
282 }
283 if {$w eq $ui_index} {
284 lappend cmd [PARENT]
285 }
286 if {$add_opts ne {}} {
287 eval lappend cmd $add_opts
288 } else {
289 lappend cmd --
290 lappend cmd $path
291 }
292
293 if {[catch {set fd [eval git_read --nice $cmd]} err]} {
294 set diff_active 0
295 unlock_index
296 ui_status [mc "Unable to display %s" [escape_path $path]]
297 error_popup [strcat [mc "Error loading diff:"] "\n\n$err"]
298 return
299 }
300
301 set ::current_diff_inheader 1
302 fconfigure $fd \
303 -blocking 0 \
304 -encoding [get_path_encoding $path] \
305 -translation lf
306 fileevent $fd readable [list read_diff $fd $cont_info]
307 }
308
309 proc read_diff {fd cont_info} {
310 global ui_diff diff_active
311 global is_3way_diff is_conflict_diff current_diff_header
312 global current_diff_queue
313
314 $ui_diff conf -state normal
315 while {[gets $fd line] >= 0} {
316 # -- Cleanup uninteresting diff header lines.
317 #
318 if {$::current_diff_inheader} {
319 if { [string match {diff --git *} $line]
320 || [string match {diff --cc *} $line]
321 || [string match {diff --combined *} $line]
322 || [string match {--- *} $line]
323 || [string match {+++ *} $line]} {
324 append current_diff_header $line "\n"
325 continue
326 }
327 }
328 if {[string match {index *} $line]} continue
329 if {$line eq {deleted file mode 120000}} {
330 set line "deleted symlink"
331 }
332 set ::current_diff_inheader 0
333
334 # -- Automatically detect if this is a 3 way diff.
335 #
336 if {[string match {@@@ *} $line]} {set is_3way_diff 1}
337
338 if {[string match {mode *} $line]
339 || [string match {new file *} $line]
340 || [regexp {^(old|new) mode *} $line]
341 || [string match {deleted file *} $line]
342 || [string match {deleted symlink} $line]
343 || [string match {Binary files * and * differ} $line]
344 || $line eq {\ No newline at end of file}
345 || [regexp {^\* Unmerged path } $line]} {
346 set tags {}
347 } elseif {$is_3way_diff} {
348 set op [string range $line 0 1]
349 switch -- $op {
350 { } {set tags {}}
351 {@@} {set tags d_@}
352 { +} {set tags d_s+}
353 { -} {set tags d_s-}
354 {+ } {set tags d_+s}
355 {- } {set tags d_-s}
356 {--} {set tags d_--}
357 {++} {
358 if {[regexp {^\+\+([<>]{7} |={7})} $line _g op]} {
359 set is_conflict_diff 1
360 set line [string replace $line 0 1 { }]
361 set tags d$op
362 } else {
363 set tags d_++
364 }
365 }
366 default {
367 puts "error: Unhandled 3 way diff marker: {$op}"
368 set tags {}
369 }
370 }
371 } else {
372 set op [string index $line 0]
373 switch -- $op {
374 { } {set tags {}}
375 {@} {set tags d_@}
376 {-} {set tags d_-}
377 {+} {
378 if {[regexp {^\+([<>]{7} |={7})} $line _g op]} {
379 set is_conflict_diff 1
380 set line [string replace $line 0 0 { }]
381 set tags d$op
382 } else {
383 set tags d_+
384 }
385 }
386 default {
387 puts "error: Unhandled 2 way diff marker: {$op}"
388 set tags {}
389 }
390 }
391 }
392 $ui_diff insert end $line $tags
393 if {[string index $line end] eq "\r"} {
394 $ui_diff tag add d_cr {end - 2c}
395 }
396 $ui_diff insert end "\n" $tags
397 }
398 $ui_diff conf -state disabled
399
400 if {[eof $fd]} {
401 close $fd
402
403 if {$current_diff_queue ne {}} {
404 advance_diff_queue $cont_info
405 return
406 }
407
408 set diff_active 0
409 unlock_index
410 set scroll_pos [lindex $cont_info 0]
411 if {$scroll_pos ne {}} {
412 update
413 $ui_diff yview moveto $scroll_pos
414 }
415 ui_ready
416
417 if {[$ui_diff index end] eq {2.0}} {
418 handle_empty_diff
419 }
420 set callback [lindex $cont_info 1]
421 if {$callback ne {}} {
422 eval $callback
423 }
424 }
425 }
426
427 proc apply_hunk {x y} {
428 global current_diff_path current_diff_header current_diff_side
429 global ui_diff ui_index file_states
430
431 if {$current_diff_path eq {} || $current_diff_header eq {}} return
432 if {![lock_index apply_hunk]} return
433
434 set apply_cmd {apply --cached --whitespace=nowarn}
435 set mi [lindex $file_states($current_diff_path) 0]
436 if {$current_diff_side eq $ui_index} {
437 set failed_msg [mc "Failed to unstage selected hunk."]
438 lappend apply_cmd --reverse
439 if {[string index $mi 0] ne {M}} {
440 unlock_index
441 return
442 }
443 } else {
444 set failed_msg [mc "Failed to stage selected hunk."]
445 if {[string index $mi 1] ne {M}} {
446 unlock_index
447 return
448 }
449 }
450
451 set s_lno [lindex [split [$ui_diff index @$x,$y] .] 0]
452 set s_lno [$ui_diff search -backwards -regexp ^@@ $s_lno.0 0.0]
453 if {$s_lno eq {}} {
454 unlock_index
455 return
456 }
457
458 set e_lno [$ui_diff search -forwards -regexp ^@@ "$s_lno + 1 lines" end]
459 if {$e_lno eq {}} {
460 set e_lno end
461 }
462
463 if {[catch {
464 set enc [get_path_encoding $current_diff_path]
465 set p [eval git_write $apply_cmd]
466 fconfigure $p -translation binary -encoding $enc
467 puts -nonewline $p $current_diff_header
468 puts -nonewline $p [$ui_diff get $s_lno $e_lno]
469 close $p} err]} {
470 error_popup [append $failed_msg "\n\n$err"]
471 unlock_index
472 return
473 }
474
475 $ui_diff conf -state normal
476 $ui_diff delete $s_lno $e_lno
477 $ui_diff conf -state disabled
478
479 if {[$ui_diff get 1.0 end] eq "\n"} {
480 set o _
481 } else {
482 set o ?
483 }
484
485 if {$current_diff_side eq $ui_index} {
486 set mi ${o}M
487 } elseif {[string index $mi 0] eq {_}} {
488 set mi M$o
489 } else {
490 set mi ?$o
491 }
492 unlock_index
493 display_file $current_diff_path $mi
494 # This should trigger shift to the next changed file
495 if {$o eq {_}} {
496 reshow_diff
497 }
498 }
499
500 proc apply_line {x y} {
501 global current_diff_path current_diff_header current_diff_side
502 global ui_diff ui_index file_states
503
504 if {$current_diff_path eq {} || $current_diff_header eq {}} return
505 if {![lock_index apply_hunk]} return
506
507 set apply_cmd {apply --cached --whitespace=nowarn}
508 set mi [lindex $file_states($current_diff_path) 0]
509 if {$current_diff_side eq $ui_index} {
510 set failed_msg [mc "Failed to unstage selected line."]
511 set to_context {+}
512 lappend apply_cmd --reverse
513 if {[string index $mi 0] ne {M}} {
514 unlock_index
515 return
516 }
517 } else {
518 set failed_msg [mc "Failed to stage selected line."]
519 set to_context {-}
520 if {[string index $mi 1] ne {M}} {
521 unlock_index
522 return
523 }
524 }
525
526 set the_l [$ui_diff index @$x,$y]
527
528 # operate only on change lines
529 set c1 [$ui_diff get "$the_l linestart"]
530 if {$c1 ne {+} && $c1 ne {-}} {
531 unlock_index
532 return
533 }
534 set sign $c1
535
536 set i_l [$ui_diff search -backwards -regexp ^@@ $the_l 0.0]
537 if {$i_l eq {}} {
538 unlock_index
539 return
540 }
541 # $i_l is now at the beginning of a line
542
543 # pick start line number from hunk header
544 set hh [$ui_diff get $i_l "$i_l + 1 lines"]
545 set hh [lindex [split $hh ,] 0]
546 set hln [lindex [split $hh -] 1]
547
548 # There is a special situation to take care of. Consider this hunk:
549 #
550 # @@ -10,4 +10,4 @@
551 # context before
552 # -old 1
553 # -old 2
554 # +new 1
555 # +new 2
556 # context after
557 #
558 # We used to keep the context lines in the order they appear in the
559 # hunk. But then it is not possible to correctly stage only
560 # "-old 1" and "+new 1" - it would result in this staged text:
561 #
562 # context before
563 # old 2
564 # new 1
565 # context after
566 #
567 # (By symmetry it is not possible to *un*stage "old 2" and "new 2".)
568 #
569 # We resolve the problem by introducing an asymmetry, namely, when
570 # a "+" line is *staged*, it is moved in front of the context lines
571 # that are generated from the "-" lines that are immediately before
572 # the "+" block. That is, we construct this patch:
573 #
574 # @@ -10,4 +10,5 @@
575 # context before
576 # +new 1
577 # old 1
578 # old 2
579 # context after
580 #
581 # But we do *not* treat "-" lines that are *un*staged in a special
582 # way.
583 #
584 # With this asymmetry it is possible to stage the change
585 # "old 1" -> "new 1" directly, and to stage the change
586 # "old 2" -> "new 2" by first staging the entire hunk and
587 # then unstaging the change "old 1" -> "new 1".
588
589 # This is non-empty if and only if we are _staging_ changes;
590 # then it accumulates the consecutive "-" lines (after converting
591 # them to context lines) in order to be moved after the "+" change
592 # line.
593 set pre_context {}
594
595 set n 0
596 set i_l [$ui_diff index "$i_l + 1 lines"]
597 set patch {}
598 while {[$ui_diff compare $i_l < "end - 1 chars"] &&
599 [$ui_diff get $i_l "$i_l + 2 chars"] ne {@@}} {
600 set next_l [$ui_diff index "$i_l + 1 lines"]
601 set c1 [$ui_diff get $i_l]
602 if {[$ui_diff compare $i_l <= $the_l] &&
603 [$ui_diff compare $the_l < $next_l]} {
604 # the line to stage/unstage
605 set ln [$ui_diff get $i_l $next_l]
606 if {$c1 eq {-}} {
607 set n [expr $n+1]
608 set patch "$patch$pre_context$ln"
609 } else {
610 set patch "$patch$ln$pre_context"
611 }
612 set pre_context {}
613 } elseif {$c1 ne {-} && $c1 ne {+}} {
614 # context line
615 set ln [$ui_diff get $i_l $next_l]
616 set patch "$patch$pre_context$ln"
617 set n [expr $n+1]
618 set pre_context {}
619 } elseif {$c1 eq $to_context} {
620 # turn change line into context line
621 set ln [$ui_diff get "$i_l + 1 chars" $next_l]
622 if {$c1 eq {-}} {
623 set pre_context "$pre_context $ln"
624 } else {
625 set patch "$patch $ln"
626 }
627 set n [expr $n+1]
628 }
629 set i_l $next_l
630 }
631 set patch "@@ -$hln,$n +$hln,[eval expr $n $sign 1] @@\n$patch"
632
633 if {[catch {
634 set enc [get_path_encoding $current_diff_path]
635 set p [eval git_write $apply_cmd]
636 fconfigure $p -translation binary -encoding $enc
637 puts -nonewline $p $current_diff_header
638 puts -nonewline $p $patch
639 close $p} err]} {
640 error_popup [append $failed_msg "\n\n$err"]
641 }
642
643 unlock_index
644 }