Merge git://repo.or.cz/git-gui
[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
23         set p $current_diff_path
24         if {$p eq {}} {
25                 # No diff is being shown.
26         } elseif {$current_diff_side eq {}
27                 || [catch {set s $file_states($p)}]
28                 || [lsearch -sorted -exact $file_lists($current_diff_side) $p] == -1} {
29                 clear_diff
30         } else {
31                 show_diff $p $current_diff_side
32         }
33 }
34
35 proc handle_empty_diff {} {
36         global current_diff_path file_states file_lists
37
38         set path $current_diff_path
39         set s $file_states($path)
40         if {[lindex $s 0] ne {_M}} return
41
42         info_popup [mc "No differences detected.
43
44 %s has no changes.
45
46 The modification date of this file was updated by another application, but the content within the file was not changed.
47
48 A rescan will be automatically started to find other files which may have the same state." [short_path $path]]
49
50         clear_diff
51         display_file $path __
52         rescan ui_ready 0
53 }
54
55 proc show_diff {path w {lno {}}} {
56         global file_states file_lists
57         global is_3way_diff diff_active repo_config
58         global ui_diff ui_index ui_workdir
59         global current_diff_path current_diff_side current_diff_header
60
61         if {$diff_active || ![lock_index read]} return
62
63         clear_diff
64         if {$lno == {}} {
65                 set lno [lsearch -sorted -exact $file_lists($w) $path]
66                 if {$lno >= 0} {
67                         incr lno
68                 }
69         }
70         if {$lno >= 1} {
71                 $w tag add in_diff $lno.0 [expr {$lno + 1}].0
72         }
73
74         set s $file_states($path)
75         set m [lindex $s 0]
76         set is_3way_diff 0
77         set diff_active 1
78         set current_diff_path $path
79         set current_diff_side $w
80         set current_diff_header {}
81         ui_status [mc "Loading diff of %s..." [escape_path $path]]
82
83         # - Git won't give us the diff, there's nothing to compare to!
84         #
85         if {$m eq {_O}} {
86                 set max_sz [expr {128 * 1024}]
87                 set type unknown
88                 if {[catch {
89                                 set type [file type $path]
90                                 switch -- $type {
91                                 directory {
92                                         set type submodule
93                                         set content {}
94                                         set sz 0
95                                 }
96                                 link {
97                                         set content [file readlink $path]
98                                         set sz [string length $content]
99                                 }
100                                 file {
101                                         set fd [open $path r]
102                                         fconfigure $fd -eofchar {}
103                                         set content [read $fd $max_sz]
104                                         close $fd
105                                         set sz [file size $path]
106                                 }
107                                 default {
108                                         error "'$type' not supported"
109                                 }
110                                 }
111                         } err ]} {
112                         set diff_active 0
113                         unlock_index
114                         ui_status [mc "Unable to display %s" [escape_path $path]]
115                         error_popup [strcat [mc "Error loading file:"] "\n\n$err"]
116                         return
117                 }
118                 $ui_diff conf -state normal
119                 if {$type eq {submodule}} {
120                         $ui_diff insert end [append \
121                                 "* " \
122                                 [mc "Git Repository (subproject)"] \
123                                 "\n"] d_@
124                 } elseif {![catch {set type [exec file $path]}]} {
125                         set n [string length $path]
126                         if {[string equal -length $n $path $type]} {
127                                 set type [string range $type $n end]
128                                 regsub {^:?\s*} $type {} type
129                         }
130                         $ui_diff insert end "* $type\n" d_@
131                 }
132                 if {[string first "\0" $content] != -1} {
133                         $ui_diff insert end \
134                                 [mc "* Binary file (not showing content)."] \
135                                 d_@
136                 } else {
137                         if {$sz > $max_sz} {
138                                 $ui_diff insert end \
139 "* Untracked file is $sz bytes.
140 * Showing only first $max_sz bytes.
141 " d_@
142                         }
143                         $ui_diff insert end $content
144                         if {$sz > $max_sz} {
145                                 $ui_diff insert end "
146 * Untracked file clipped here by [appname].
147 * To see the entire file, use an external editor.
148 " d_@
149                         }
150                 }
151                 $ui_diff conf -state disabled
152                 set diff_active 0
153                 unlock_index
154                 ui_ready
155                 return
156         }
157
158         set cmd [list]
159         if {$w eq $ui_index} {
160                 lappend cmd diff-index
161                 lappend cmd --cached
162         } elseif {$w eq $ui_workdir} {
163                 if {[string index $m 0] eq {U}} {
164                         lappend cmd diff
165                 } else {
166                         lappend cmd diff-files
167                 }
168         }
169
170         lappend cmd -p
171         lappend cmd --no-color
172         if {$repo_config(gui.diffcontext) >= 0} {
173                 lappend cmd "-U$repo_config(gui.diffcontext)"
174         }
175         if {$w eq $ui_index} {
176                 lappend cmd [PARENT]
177         }
178         lappend cmd --
179         lappend cmd $path
180
181         if {[catch {set fd [eval git_read --nice $cmd]} err]} {
182                 set diff_active 0
183                 unlock_index
184                 ui_status [mc "Unable to display %s" [escape_path $path]]
185                 error_popup [strcat [mc "Error loading diff:"] "\n\n$err"]
186                 return
187         }
188
189         fconfigure $fd \
190                 -blocking 0 \
191                 -encoding binary \
192                 -translation binary
193         fileevent $fd readable [list read_diff $fd]
194 }
195
196 proc read_diff {fd} {
197         global ui_diff diff_active
198         global is_3way_diff current_diff_header
199
200         $ui_diff conf -state normal
201         while {[gets $fd line] >= 0} {
202                 # -- Cleanup uninteresting diff header lines.
203                 #
204                 if {   [string match {diff --git *}      $line]
205                         || [string match {diff --cc *}       $line]
206                         || [string match {diff --combined *} $line]
207                         || [string match {--- *}             $line]
208                         || [string match {+++ *}             $line]} {
209                         append current_diff_header $line "\n"
210                         continue
211                 }
212                 if {[string match {index *} $line]} continue
213                 if {$line eq {deleted file mode 120000}} {
214                         set line "deleted symlink"
215                 }
216
217                 # -- Automatically detect if this is a 3 way diff.
218                 #
219                 if {[string match {@@@ *} $line]} {set is_3way_diff 1}
220
221                 if {[string match {mode *} $line]
222                         || [string match {new file *} $line]
223                         || [regexp {^(old|new) mode *} $line]
224                         || [string match {deleted file *} $line]
225                         || [string match {deleted symlink} $line]
226                         || [string match {Binary files * and * differ} $line]
227                         || $line eq {\ No newline at end of file}
228                         || [regexp {^\* Unmerged path } $line]} {
229                         set tags {}
230                 } elseif {$is_3way_diff} {
231                         set op [string range $line 0 1]
232                         switch -- $op {
233                         {  } {set tags {}}
234                         {@@} {set tags d_@}
235                         { +} {set tags d_s+}
236                         { -} {set tags d_s-}
237                         {+ } {set tags d_+s}
238                         {- } {set tags d_-s}
239                         {--} {set tags d_--}
240                         {++} {
241                                 if {[regexp {^\+\+([<>]{7} |={7})} $line _g op]} {
242                                         set line [string replace $line 0 1 {  }]
243                                         set tags d$op
244                                 } else {
245                                         set tags d_++
246                                 }
247                         }
248                         default {
249                                 puts "error: Unhandled 3 way diff marker: {$op}"
250                                 set tags {}
251                         }
252                         }
253                 } else {
254                         set op [string index $line 0]
255                         switch -- $op {
256                         { } {set tags {}}
257                         {@} {set tags d_@}
258                         {-} {set tags d_-}
259                         {+} {
260                                 if {[regexp {^\+([<>]{7} |={7})} $line _g op]} {
261                                         set line [string replace $line 0 0 { }]
262                                         set tags d$op
263                                 } else {
264                                         set tags d_+
265                                 }
266                         }
267                         default {
268                                 puts "error: Unhandled 2 way diff marker: {$op}"
269                                 set tags {}
270                         }
271                         }
272                 }
273                 $ui_diff insert end $line $tags
274                 if {[string index $line end] eq "\r"} {
275                         $ui_diff tag add d_cr {end - 2c}
276                 }
277                 $ui_diff insert end "\n" $tags
278         }
279         $ui_diff conf -state disabled
280
281         if {[eof $fd]} {
282                 close $fd
283                 set diff_active 0
284                 unlock_index
285                 ui_ready
286
287                 if {[$ui_diff index end] eq {2.0}} {
288                         handle_empty_diff
289                 }
290         }
291 }
292
293 proc apply_hunk {x y} {
294         global current_diff_path current_diff_header current_diff_side
295         global ui_diff ui_index file_states
296
297         if {$current_diff_path eq {} || $current_diff_header eq {}} return
298         if {![lock_index apply_hunk]} return
299
300         set apply_cmd {apply --cached --whitespace=nowarn}
301         set mi [lindex $file_states($current_diff_path) 0]
302         if {$current_diff_side eq $ui_index} {
303                 set failed_msg [mc "Failed to unstage selected hunk."]
304                 lappend apply_cmd --reverse
305                 if {[string index $mi 0] ne {M}} {
306                         unlock_index
307                         return
308                 }
309         } else {
310                 set failed_msg [mc "Failed to stage selected hunk."]
311                 if {[string index $mi 1] ne {M}} {
312                         unlock_index
313                         return
314                 }
315         }
316
317         set s_lno [lindex [split [$ui_diff index @$x,$y] .] 0]
318         set s_lno [$ui_diff search -backwards -regexp ^@@ $s_lno.0 0.0]
319         if {$s_lno eq {}} {
320                 unlock_index
321                 return
322         }
323
324         set e_lno [$ui_diff search -forwards -regexp ^@@ "$s_lno + 1 lines" end]
325         if {$e_lno eq {}} {
326                 set e_lno end
327         }
328
329         if {[catch {
330                 set p [eval git_write $apply_cmd]
331                 fconfigure $p -translation binary -encoding binary
332                 puts -nonewline $p $current_diff_header
333                 puts -nonewline $p [$ui_diff get $s_lno $e_lno]
334                 close $p} err]} {
335                 error_popup [append $failed_msg "\n\n$err"]
336                 unlock_index
337                 return
338         }
339
340         $ui_diff conf -state normal
341         $ui_diff delete $s_lno $e_lno
342         $ui_diff conf -state disabled
343
344         if {[$ui_diff get 1.0 end] eq "\n"} {
345                 set o _
346         } else {
347                 set o ?
348         }
349
350         if {$current_diff_side eq $ui_index} {
351                 set mi ${o}M
352         } elseif {[string index $mi 0] eq {_}} {
353                 set mi M$o
354         } else {
355                 set mi ?$o
356         }
357         unlock_index
358         display_file $current_diff_path $mi
359         if {$o eq {_}} {
360                 clear_diff
361         }
362 }