1# git-gui diff viewer
2# Copyright (C) 2006, 2007 Shawn Pearce
3proc apply_tab_size {{firsttab {}}} {
5 global have_tk85 repo_config ui_diff
6 set w [font measure font_diff "0"]
8 if {$have_tk85 && $firsttab != 0} {
9 $ui_diff configure -tabs [list [expr {$firsttab * $w}] [expr {($firsttab + $repo_config(gui.tabsize)) * $w}]]
10 } elseif {$have_tk85 || $repo_config(gui.tabsize) != 8} {
11 $ui_diff configure -tabs [expr {$repo_config(gui.tabsize) * $w}]
12 } else {
13 $ui_diff configure -tabs {}
14 }
15}
16proc clear_diff {} {
18 global ui_diff current_diff_path current_diff_header
19 global ui_index ui_workdir
20 $ui_diff conf -state normal
22 $ui_diff delete 0.0 end
23 $ui_diff conf -state disabled
24 set current_diff_path {}
26 set current_diff_header {}
27 $ui_index tag remove in_diff 0.0 end
29 $ui_workdir tag remove in_diff 0.0 end
30}
31proc reshow_diff {{after {}}} {
33 global file_states file_lists
34 global current_diff_path current_diff_side
35 global ui_diff
36 set p $current_diff_path
38 if {$p eq {}} {
39 # No diff is being shown.
40 } elseif {$current_diff_side eq {}} {
41 clear_diff
42 } elseif {[catch {set s $file_states($p)}]
43 || [lsearch -sorted -exact $file_lists($current_diff_side) $p] == -1} {
44 if {[find_next_diff $current_diff_side $p {} {[^O]}]} {
46 next_diff $after
47 } else {
48 clear_diff
49 }
50 } else {
51 set save_pos [lindex [$ui_diff yview] 0]
52 show_diff $p $current_diff_side {} $save_pos $after
53 }
54}
55proc force_diff_encoding {enc} {
57 global current_diff_path
58
59 if {$current_diff_path ne {}} {
60 force_path_encoding $current_diff_path $enc
61 reshow_diff
62 }
63}
64proc handle_empty_diff {} {
66 global current_diff_path file_states file_lists
67 global diff_empty_count
68 set path $current_diff_path
70 set s $file_states($path)
71 if {[lindex $s 0] ne {_M} || [has_textconv $path]} return
72 # Prevent infinite rescan loops
74 incr diff_empty_count
75 if {$diff_empty_count > 1} return
76 info_popup [mc "No differences detected.
78%s has no changes.
80The modification date of this file was updated by another application, but the content within the file was not changed.
82A rescan will be automatically started to find other files which may have the same state." [short_path $path]]
84 clear_diff
86 display_file $path __
87 rescan ui_ready 0
88}
89proc show_diff {path w {lno {}} {scroll_pos {}} {callback {}}} {
91 global file_states file_lists
92 global is_3way_diff is_conflict_diff diff_active repo_config
93 global ui_diff ui_index ui_workdir
94 global current_diff_path current_diff_side current_diff_header
95 global current_diff_queue
96 if {$diff_active || ![lock_index read]} return
98 clear_diff
100 if {$lno == {}} {
101 set lno [lsearch -sorted -exact $file_lists($w) $path]
102 if {$lno >= 0} {
103 incr lno
104 }
105 }
106 if {$lno >= 1} {
107 $w tag add in_diff $lno.0 [expr {$lno + 1}].0
108 $w see $lno.0
109 }
110 set s $file_states($path)
112 set m [lindex $s 0]
113 set is_conflict_diff 0
114 set current_diff_path $path
115 set current_diff_side $w
116 set current_diff_queue {}
117 ui_status [mc "Loading diff of %s..." [escape_path $path]]
118 set cont_info [list $scroll_pos $callback]
120 apply_tab_size 0
122 if {[string first {U} $m] >= 0} {
124 merge_load_stages $path [list show_unmerged_diff $cont_info]
125 } elseif {$m eq {_O}} {
126 show_other_diff $path $w $m $cont_info
127 } else {
128 start_show_diff $cont_info
129 }
130 global current_diff_path selected_paths
132 set selected_paths($current_diff_path) 1
133}
134proc show_unmerged_diff {cont_info} {
136 global current_diff_path current_diff_side
137 global merge_stages ui_diff is_conflict_diff
138 global current_diff_queue
139 if {$merge_stages(2) eq {}} {
141 set is_conflict_diff 1
142 lappend current_diff_queue \
143 [list [mc "LOCAL: deleted\nREMOTE:\n"] d= \
144 [list ":1:$current_diff_path" ":3:$current_diff_path"]]
145 } elseif {$merge_stages(3) eq {}} {
146 set is_conflict_diff 1
147 lappend current_diff_queue \
148 [list [mc "REMOTE: deleted\nLOCAL:\n"] d= \
149 [list ":1:$current_diff_path" ":2:$current_diff_path"]]
150 } elseif {[lindex $merge_stages(1) 0] eq {120000}
151 || [lindex $merge_stages(2) 0] eq {120000}
152 || [lindex $merge_stages(3) 0] eq {120000}} {
153 set is_conflict_diff 1
154 lappend current_diff_queue \
155 [list [mc "LOCAL:\n"] d= \
156 [list ":1:$current_diff_path" ":2:$current_diff_path"]]
157 lappend current_diff_queue \
158 [list [mc "REMOTE:\n"] d= \
159 [list ":1:$current_diff_path" ":3:$current_diff_path"]]
160 } else {
161 start_show_diff $cont_info
162 return
163 }
164 advance_diff_queue $cont_info
166}
167proc advance_diff_queue {cont_info} {
169 global current_diff_queue ui_diff
170 set item [lindex $current_diff_queue 0]
172 set current_diff_queue [lrange $current_diff_queue 1 end]
173 $ui_diff conf -state normal
175 $ui_diff insert end [lindex $item 0] [lindex $item 1]
176 $ui_diff conf -state disabled
177 start_show_diff $cont_info [lindex $item 2]
179}
180proc show_other_diff {path w m cont_info} {
182 global file_states file_lists
183 global is_3way_diff diff_active repo_config
184 global ui_diff ui_index ui_workdir
185 global current_diff_path current_diff_side current_diff_header
186 # - Git won't give us the diff, there's nothing to compare to!
188 #
189 if {$m eq {_O}} {
190 set max_sz 100000
191 set type unknown
192 if {[catch {
193 set type [file type $path]
194 switch -- $type {
195 directory {
196 set type submodule
197 set content {}
198 set sz 0
199 }
200 link {
201 set content [file readlink $path]
202 set sz [string length $content]
203 }
204 file {
205 set fd [open $path r]
206 fconfigure $fd \
207 -eofchar {} \
208 -encoding [get_path_encoding $path]
209 set content [read $fd $max_sz]
210 close $fd
211 set sz [file size $path]
212 }
213 default {
214 error "'$type' not supported"
215 }
216 }
217 } err ]} {
218 set diff_active 0
219 unlock_index
220 ui_status [mc "Unable to display %s" [escape_path $path]]
221 error_popup [strcat [mc "Error loading file:"] "\n\n$err"]
222 return
223 }
224 $ui_diff conf -state normal
225 if {$type eq {submodule}} {
226 $ui_diff insert end \
227 "* [mc "Git Repository (subproject)"]\n" \
228 d_info
229 } elseif {![catch {set type [exec file $path]}]} {
230 set n [string length $path]
231 if {[string equal -length $n $path $type]} {
232 set type [string range $type $n end]
233 regsub {^:?\s*} $type {} type
234 }
235 $ui_diff insert end "* $type\n" d_info
236 }
237 if {[string first "\0" $content] != -1} {
238 $ui_diff insert end \
239 [mc "* Binary file (not showing content)."] \
240 d_info
241 } else {
242 if {$sz > $max_sz} {
243 $ui_diff insert end [mc \
244"* Untracked file is %d bytes.
245* Showing only first %d bytes.
246" $sz $max_sz] d_info
247 }
248 $ui_diff insert end $content
249 if {$sz > $max_sz} {
250 $ui_diff insert end [mc "
251* Untracked file clipped here by %s.
252* To see the entire file, use an external editor.
253" [appname]] d_info
254 }
255 }
256 $ui_diff conf -state disabled
257 set diff_active 0
258 unlock_index
259 set scroll_pos [lindex $cont_info 0]
260 if {$scroll_pos ne {}} {
261 update
262 $ui_diff yview moveto $scroll_pos
263 }
264 ui_ready
265 set callback [lindex $cont_info 1]
266 if {$callback ne {}} {
267 eval $callback
268 }
269 return
270 }
271}
272proc get_conflict_marker_size {path} {
274 set size 7
275 catch {
276 set fd_rc [eval [list git_read check-attr "conflict-marker-size" -- $path]]
277 set ret [gets $fd_rc line]
278 close $fd_rc
279 if {$ret > 0} {
280 regexp {.*: conflict-marker-size: (\d+)$} $line line size
281 }
282 }
283 return $size
284}
285proc start_show_diff {cont_info {add_opts {}}} {
287 global file_states file_lists
288 global is_3way_diff is_submodule_diff diff_active repo_config
289 global ui_diff ui_index ui_workdir
290 global current_diff_path current_diff_side current_diff_header
291 set path $current_diff_path
293 set w $current_diff_side
294 set s $file_states($path)
296 set m [lindex $s 0]
297 set is_3way_diff 0
298 set is_submodule_diff 0
299 set diff_active 1
300 set current_diff_header {}
301 set conflict_size [get_conflict_marker_size $path]
302 set cmd [list]
304 if {$w eq $ui_index} {
305 lappend cmd diff-index
306 lappend cmd --cached
307 if {[git-version >= "1.7.2"]} {
308 lappend cmd --ignore-submodules=dirty
309 }
310 } elseif {$w eq $ui_workdir} {
311 if {[string first {U} $m] >= 0} {
312 lappend cmd diff
313 } else {
314 lappend cmd diff-files
315 }
316 }
317 if {![is_config_false gui.textconv] && [git-version >= 1.6.1]} {
318 lappend cmd --textconv
319 }
320 if {[string match {160000 *} [lindex $s 2]]
322 || [string match {160000 *} [lindex $s 3]]} {
323 set is_submodule_diff 1
324 if {[git-version >= "1.6.6"]} {
326 lappend cmd --submodule
327 }
328 }
329 lappend cmd -p
331 lappend cmd --color
332 set cmd [concat $cmd $repo_config(gui.diffopts)]
333 if {$repo_config(gui.diffcontext) >= 1} {
334 lappend cmd "-U$repo_config(gui.diffcontext)"
335 }
336 if {$w eq $ui_index} {
337 lappend cmd [PARENT]
338 }
339 if {$add_opts ne {}} {
340 eval lappend cmd $add_opts
341 } else {
342 lappend cmd --
343 lappend cmd $path
344 }
345 if {$is_submodule_diff && [git-version < "1.6.6"]} {
347 if {$w eq $ui_index} {
348 set cmd [list submodule summary --cached -- $path]
349 } else {
350 set cmd [list submodule summary --files -- $path]
351 }
352 }
353 if {[catch {set fd [eval git_read --nice $cmd]} err]} {
355 set diff_active 0
356 unlock_index
357 ui_status [mc "Unable to display %s" [escape_path $path]]
358 error_popup [strcat [mc "Error loading diff:"] "\n\n$err"]
359 return
360 }
361 set ::current_diff_inheader 1
363 fconfigure $fd \
364 -blocking 0 \
365 -encoding [get_path_encoding $path] \
366 -translation lf
367 fileevent $fd readable [list read_diff $fd $conflict_size $cont_info]
368}
369proc parse_color_line {line} {
371 set start 0
372 set result ""
373 set markup [list]
374 set regexp {\033\[((?:\d+;)*\d+)?m}
375 set need_reset 0
376 while {[regexp -indices -start $start $regexp $line match code]} {
377 foreach {begin end} $match break
378 append result [string range $line $start [expr {$begin - 1}]]
379 set pos [string length $result]
380 set col [eval [linsert $code 0 string range $line]]
381 set start [incr end]
382 if {$col eq "0" || $col eq ""} {
383 if {!$need_reset} continue
384 set need_reset 0
385 } else {
386 set need_reset 1
387 }
388 lappend markup $pos $col
389 }
390 append result [string range $line $start end]
391 if {[llength $markup] < 4} {set markup {}}
392 return [list $result $markup]
393}
394proc read_diff {fd conflict_size cont_info} {
396 global ui_diff diff_active is_submodule_diff
397 global is_3way_diff is_conflict_diff current_diff_header
398 global current_diff_queue
399 global diff_empty_count
400 $ui_diff conf -state normal
402 while {[gets $fd line] >= 0} {
403 foreach {line markup} [parse_color_line $line] break
404 set line [string map {\033 ^} $line]
405 set tags {}
407 # -- Check for start of diff header.
409 if { [string match {diff --git *} $line]
410 || [string match {diff --cc *} $line]
411 || [string match {diff --combined *} $line]} {
412 set ::current_diff_inheader 1
413 }
414 # -- Check for end of diff header (any hunk line will do this).
416 #
417 if {[regexp {^@@+ } $line]} {set ::current_diff_inheader 0}
418 # -- Automatically detect if this is a 3 way diff.
420 #
421 if {[string match {@@@ *} $line]} {
422 set is_3way_diff 1
423 apply_tab_size 1
424 }
425 if {$::current_diff_inheader} {
427 # -- These two lines stop a diff header and shouldn't be in there
429 if { [string match {Binary files * and * differ} $line]
430 || [regexp {^\* Unmerged path } $line]} {
431 set ::current_diff_inheader 0
432 } else {
433 append current_diff_header $line "\n"
434 }
435 # -- Cleanup uninteresting diff header lines.
437 #
438 if { [string match {diff --git *} $line]
439 || [string match {diff --cc *} $line]
440 || [string match {diff --combined *} $line]
441 || [string match {--- *} $line]
442 || [string match {+++ *} $line]
443 || [string match {index *} $line]} {
444 continue
445 }
446 # -- Name it symlink, not 120000
448 # Note, that the original line is in $current_diff_header
449 regsub {^(deleted|new) file mode 120000} $line {\1 symlink} line
450 } elseif { $line eq {\ No newline at end of file}} {
452 # -- Handle some special lines
453 } elseif {$is_3way_diff} {
454 set op [string range $line 0 1]
455 switch -- $op {
456 { } {set tags {}}
457 {@@} {set tags d_@}
458 { +} {set tags d_s+}
459 { -} {set tags d_s-}
460 {+ } {set tags d_+s}
461 {- } {set tags d_-s}
462 {--} {set tags d_--}
463 {++} {
464 set regexp [string map [list %conflict_size $conflict_size]\
465 {^\+\+([<>=]){%conflict_size}(?: |$)}]
466 if {[regexp $regexp $line _g op]} {
467 set is_conflict_diff 1
468 set line [string replace $line 0 1 { }]
469 set tags d$op
470 } else {
471 set tags d_++
472 }
473 }
474 default {
475 puts "error: Unhandled 3 way diff marker: {$op}"
476 set tags {}
477 }
478 }
479 } elseif {$is_submodule_diff} {
480 if {$line == ""} continue
481 if {[regexp {^Submodule } $line]} {
482 set tags d_info
483 } elseif {[regexp {^\* } $line]} {
484 set line [string replace $line 0 1 {Submodule }]
485 set tags d_info
486 } else {
487 set op [string range $line 0 2]
488 switch -- $op {
489 { <} {set tags d_-}
490 { >} {set tags d_+}
491 { W} {set tags {}}
492 default {
493 puts "error: Unhandled submodule diff marker: {$op}"
494 set tags {}
495 }
496 }
497 }
498 } else {
499 set op [string index $line 0]
500 switch -- $op {
501 { } {set tags {}}
502 {@} {set tags d_@}
503 {-} {set tags d_-}
504 {+} {
505 set regexp [string map [list %conflict_size $conflict_size]\
506 {^\+([<>=]){%conflict_size}(?: |$)}]
507 if {[regexp $regexp $line _g op]} {
508 set is_conflict_diff 1
509 set tags d$op
510 } else {
511 set tags d_+
512 }
513 }
514 default {
515 puts "error: Unhandled 2 way diff marker: {$op}"
516 set tags {}
517 }
518 }
519 }
520 set mark [$ui_diff index "end - 1 line linestart"]
521 $ui_diff insert end $line $tags
522 if {[string index $line end] eq "\r"} {
523 $ui_diff tag add d_cr {end - 2c}
524 }
525 $ui_diff insert end "\n" $tags
526 foreach {posbegin colbegin posend colend} $markup {
528 set prefix clr
529 foreach style [lsort -integer [split $colbegin ";"]] {
530 if {$style eq "7"} {append prefix i; continue}
531 if {$style != 4 && ($style < 30 || $style > 47)} {continue}
532 set a "$mark linestart + $posbegin chars"
533 set b "$mark linestart + $posend chars"
534 catch {$ui_diff tag add $prefix$style $a $b}
535 }
536 }
537 }
538 $ui_diff conf -state disabled
539 if {[eof $fd]} {
541 close $fd
542 if {$current_diff_queue ne {}} {
544 advance_diff_queue $cont_info
545 return
546 }
547 set diff_active 0
549 unlock_index
550 set scroll_pos [lindex $cont_info 0]
551 if {$scroll_pos ne {}} {
552 update
553 $ui_diff yview moveto $scroll_pos
554 }
555 ui_ready
556 if {[$ui_diff index end] eq {2.0}} {
558 handle_empty_diff
559 } else {
560 set diff_empty_count 0
561 }
562 set callback [lindex $cont_info 1]
564 if {$callback ne {}} {
565 eval $callback
566 }
567 }
568}
569proc apply_hunk {x y} {
571 global current_diff_path current_diff_header current_diff_side
572 global ui_diff ui_index file_states
573 if {$current_diff_path eq {} || $current_diff_header eq {}} return
575 if {![lock_index apply_hunk]} return
576 set apply_cmd {apply --cached --whitespace=nowarn}
578 set mi [lindex $file_states($current_diff_path) 0]
579 if {$current_diff_side eq $ui_index} {
580 set failed_msg [mc "Failed to unstage selected hunk."]
581 lappend apply_cmd --reverse
582 if {[string index $mi 0] ne {M}} {
583 unlock_index
584 return
585 }
586 } else {
587 set failed_msg [mc "Failed to stage selected hunk."]
588 if {[string index $mi 1] ne {M}} {
589 unlock_index
590 return
591 }
592 }
593 set s_lno [lindex [split [$ui_diff index @$x,$y] .] 0]
595 set s_lno [$ui_diff search -backwards -regexp ^@@ $s_lno.0 0.0]
596 if {$s_lno eq {}} {
597 unlock_index
598 return
599 }
600 set e_lno [$ui_diff search -forwards -regexp ^@@ "$s_lno + 1 lines" end]
602 if {$e_lno eq {}} {
603 set e_lno end
604 }
605 if {[catch {
607 set enc [get_path_encoding $current_diff_path]
608 set p [eval git_write $apply_cmd]
609 fconfigure $p -translation binary -encoding $enc
610 puts -nonewline $p $current_diff_header
611 puts -nonewline $p [$ui_diff get $s_lno $e_lno]
612 close $p} err]} {
613 error_popup "$failed_msg\n\n$err"
614 unlock_index
615 return
616 }
617 $ui_diff conf -state normal
619 $ui_diff delete $s_lno $e_lno
620 $ui_diff conf -state disabled
621 if {[$ui_diff get 1.0 end] eq "\n"} {
623 set o _
624 } else {
625 set o ?
626 }
627 if {$current_diff_side eq $ui_index} {
629 set mi ${o}M
630 } elseif {[string index $mi 0] eq {_}} {
631 set mi M$o
632 } else {
633 set mi ?$o
634 }
635 unlock_index
636 display_file $current_diff_path $mi
637 # This should trigger shift to the next changed file
638 if {$o eq {_}} {
639 reshow_diff
640 }
641}
642proc apply_range_or_line {x y} {
644 global current_diff_path current_diff_header current_diff_side
645 global ui_diff ui_index file_states
646 set selected [$ui_diff tag nextrange sel 0.0]
648 if {$selected == {}} {
650 set first [$ui_diff index "@$x,$y"]
651 set last $first
652 } else {
653 set first [lindex $selected 0]
654 set last [lindex $selected 1]
655 }
656 set first_l [$ui_diff index "$first linestart"]
658 set last_l [$ui_diff index "$last lineend"]
659 if {$current_diff_path eq {} || $current_diff_header eq {}} return
661 if {![lock_index apply_hunk]} return
662 set apply_cmd {apply --cached --whitespace=nowarn}
664 set mi [lindex $file_states($current_diff_path) 0]
665 if {$current_diff_side eq $ui_index} {
666 set failed_msg [mc "Failed to unstage selected line."]
667 set to_context {+}
668 lappend apply_cmd --reverse
669 if {[string index $mi 0] ne {M}} {
670 unlock_index
671 return
672 }
673 } else {
674 set failed_msg [mc "Failed to stage selected line."]
675 set to_context {-}
676 if {[string index $mi 1] ne {M}} {
677 unlock_index
678 return
679 }
680 }
681 set wholepatch {}
683 while {$first_l < $last_l} {
685 set i_l [$ui_diff search -backwards -regexp ^@@ $first_l 0.0]
686 if {$i_l eq {}} {
687 # If there's not a @@ above, then the selected range
688 # must have come before the first_l @@
689 set i_l [$ui_diff search -regexp ^@@ $first_l $last_l]
690 }
691 if {$i_l eq {}} {
692 unlock_index
693 return
694 }
695 # $i_l is now at the beginning of a line
696 # pick start line number from hunk header
698 set hh [$ui_diff get $i_l "$i_l + 1 lines"]
699 set hh [lindex [split $hh ,] 0]
700 set hln [lindex [split $hh -] 1]
701 set hln [lindex [split $hln " "] 0]
702 # There is a special situation to take care of. Consider this
704 # hunk:
705 #
706 # @@ -10,4 +10,4 @@
707 # context before
708 # -old 1
709 # -old 2
710 # +new 1
711 # +new 2
712 # context after
713 #
714 # We used to keep the context lines in the order they appear in
715 # the hunk. But then it is not possible to correctly stage only
716 # "-old 1" and "+new 1" - it would result in this staged text:
717 #
718 # context before
719 # old 2
720 # new 1
721 # context after
722 #
723 # (By symmetry it is not possible to *un*stage "old 2" and "new
724 # 2".)
725 #
726 # We resolve the problem by introducing an asymmetry, namely,
727 # when a "+" line is *staged*, it is moved in front of the
728 # context lines that are generated from the "-" lines that are
729 # immediately before the "+" block. That is, we construct this
730 # patch:
731 #
732 # @@ -10,4 +10,5 @@
733 # context before
734 # +new 1
735 # old 1
736 # old 2
737 # context after
738 #
739 # But we do *not* treat "-" lines that are *un*staged in a
740 # special way.
741 #
742 # With this asymmetry it is possible to stage the change "old
743 # 1" -> "new 1" directly, and to stage the change "old 2" ->
744 # "new 2" by first staging the entire hunk and then unstaging
745 # the change "old 1" -> "new 1".
746 #
747 # Applying multiple lines adds complexity to the special
748 # situation. The pre_context must be moved after the entire
749 # first block of consecutive staged "+" lines, so that
750 # staging both additions gives the following patch:
751 #
752 # @@ -10,4 +10,6 @@
753 # context before
754 # +new 1
755 # +new 2
756 # old 1
757 # old 2
758 # context after
759 # This is non-empty if and only if we are _staging_ changes;
761 # then it accumulates the consecutive "-" lines (after
762 # converting them to context lines) in order to be moved after
763 # "+" change lines.
764 set pre_context {}
765 set n 0
767 set m 0
768 set i_l [$ui_diff index "$i_l + 1 lines"]
769 set patch {}
770 while {[$ui_diff compare $i_l < "end - 1 chars"] &&
771 [$ui_diff get $i_l "$i_l + 2 chars"] ne {@@}} {
772 set next_l [$ui_diff index "$i_l + 1 lines"]
773 set c1 [$ui_diff get $i_l]
774 if {[$ui_diff compare $first_l <= $i_l] &&
775 [$ui_diff compare $i_l < $last_l] &&
776 ($c1 eq {-} || $c1 eq {+})} {
777 # a line to stage/unstage
778 set ln [$ui_diff get $i_l $next_l]
779 if {$c1 eq {-}} {
780 set n [expr $n+1]
781 set patch "$patch$pre_context$ln"
782 set pre_context {}
783 } else {
784 set m [expr $m+1]
785 set patch "$patch$ln"
786 }
787 } elseif {$c1 ne {-} && $c1 ne {+}} {
788 # context line
789 set ln [$ui_diff get $i_l $next_l]
790 set patch "$patch$pre_context$ln"
791 # Skip the "\ No newline at end of
792 # file". Depending on the locale setting
793 # we don't know what this line looks
794 # like exactly. The only thing we do
795 # know is that it starts with "\ "
796 if {![string match {\\ *} $ln]} {
797 set n [expr $n+1]
798 set m [expr $m+1]
799 }
800 set pre_context {}
801 } elseif {$c1 eq $to_context} {
802 # turn change line into context line
803 set ln [$ui_diff get "$i_l + 1 chars" $next_l]
804 if {$c1 eq {-}} {
805 set pre_context "$pre_context $ln"
806 } else {
807 set patch "$patch $ln"
808 }
809 set n [expr $n+1]
810 set m [expr $m+1]
811 } else {
812 # a change in the opposite direction of
813 # to_context which is outside the range of
814 # lines to apply.
815 set patch "$patch$pre_context"
816 set pre_context {}
817 }
818 set i_l $next_l
819 }
820 set patch "$patch$pre_context"
821 set wholepatch "$wholepatch@@ -$hln,$n +$hln,$m @@\n$patch"
822 set first_l [$ui_diff index "$next_l + 1 lines"]
823 }
824 if {[catch {
826 set enc [get_path_encoding $current_diff_path]
827 set p [eval git_write $apply_cmd]
828 fconfigure $p -translation binary -encoding $enc
829 puts -nonewline $p $current_diff_header
830 puts -nonewline $p $wholepatch
831 close $p} err]} {
832 error_popup "$failed_msg\n\n$err"
833 }
834 unlock_index
836}