Merge commit 'v1.6.0' into jc/checkout-reflog-fix
[gitweb.git] / git-gui / lib / diff.tcl
index d04f6dbde2c468274770aa5543758186803e9ac5..52b79e4a1f476c2ee9b65087f66a352a25ed0903 100644 (file)
@@ -19,6 +19,7 @@ proc clear_diff {} {
 proc reshow_diff {} {
        global file_states file_lists
        global current_diff_path current_diff_side
+       global ui_diff
 
        set p $current_diff_path
        if {$p eq {}} {
@@ -28,7 +29,8 @@ proc reshow_diff {} {
                || [lsearch -sorted -exact $file_lists($current_diff_side) $p] == -1} {
                clear_diff
        } else {
-               show_diff $p $current_diff_side
+               set save_pos [lindex [$ui_diff yview] 0]
+               show_diff $p $current_diff_side {} $save_pos
        }
 }
 
@@ -52,7 +54,7 @@ A rescan will be automatically started to find other files which may have the sa
        rescan ui_ready 0
 }
 
-proc show_diff {path w {lno {}}} {
+proc show_diff {path w {lno {}} {scroll_pos {}}} {
        global file_states file_lists
        global is_3way_diff diff_active repo_config
        global ui_diff ui_index ui_workdir
@@ -151,6 +153,10 @@ proc show_diff {path w {lno {}}} {
                $ui_diff conf -state disabled
                set diff_active 0
                unlock_index
+               if {$scroll_pos ne {}} {
+                       update
+                       $ui_diff yview moveto $scroll_pos
+               }
                ui_ready
                return
        }
@@ -190,10 +196,10 @@ proc show_diff {path w {lno {}}} {
                -blocking 0 \
                -encoding binary \
                -translation binary
-       fileevent $fd readable [list read_diff $fd]
+       fileevent $fd readable [list read_diff $fd $scroll_pos]
 }
 
-proc read_diff {fd} {
+proc read_diff {fd scroll_pos} {
        global ui_diff diff_active
        global is_3way_diff current_diff_header
 
@@ -282,6 +288,10 @@ proc read_diff {fd} {
                close $fd
                set diff_active 0
                unlock_index
+               if {$scroll_pos ne {}} {
+                       update
+                       $ui_diff yview moveto $scroll_pos
+               }
                ui_ready
 
                if {[$ui_diff index end] eq {2.0}} {
@@ -362,3 +372,148 @@ proc apply_hunk {x y} {
                set current_diff_path $current_diff_path
        }
 }
+
+proc apply_line {x y} {
+       global current_diff_path current_diff_header current_diff_side
+       global ui_diff ui_index file_states
+
+       if {$current_diff_path eq {} || $current_diff_header eq {}} return
+       if {![lock_index apply_hunk]} return
+
+       set apply_cmd {apply --cached --whitespace=nowarn}
+       set mi [lindex $file_states($current_diff_path) 0]
+       if {$current_diff_side eq $ui_index} {
+               set failed_msg [mc "Failed to unstage selected line."]
+               set to_context {+}
+               lappend apply_cmd --reverse
+               if {[string index $mi 0] ne {M}} {
+                       unlock_index
+                       return
+               }
+       } else {
+               set failed_msg [mc "Failed to stage selected line."]
+               set to_context {-}
+               if {[string index $mi 1] ne {M}} {
+                       unlock_index
+                       return
+               }
+       }
+
+       set the_l [$ui_diff index @$x,$y]
+
+       # operate only on change lines
+       set c1 [$ui_diff get "$the_l linestart"]
+       if {$c1 ne {+} && $c1 ne {-}} {
+               unlock_index
+               return
+       }
+       set sign $c1
+
+       set i_l [$ui_diff search -backwards -regexp ^@@ $the_l 0.0]
+       if {$i_l eq {}} {
+               unlock_index
+               return
+       }
+       # $i_l is now at the beginning of a line
+
+       # pick start line number from hunk header
+       set hh [$ui_diff get $i_l "$i_l + 1 lines"]
+       set hh [lindex [split $hh ,] 0]
+       set hln [lindex [split $hh -] 1]
+
+       # There is a special situation to take care of. Consider this hunk:
+       #
+       #    @@ -10,4 +10,4 @@
+       #     context before
+       #    -old 1
+       #    -old 2
+       #    +new 1
+       #    +new 2
+       #     context after
+       #
+       # We used to keep the context lines in the order they appear in the
+       # hunk. But then it is not possible to correctly stage only
+       # "-old 1" and "+new 1" - it would result in this staged text:
+       #
+       #    context before
+       #    old 2
+       #    new 1
+       #    context after
+       #
+       # (By symmetry it is not possible to *un*stage "old 2" and "new 2".)
+       #
+       # We resolve the problem by introducing an asymmetry, namely, when
+       # a "+" line is *staged*, it is moved in front of the context lines
+       # that are generated from the "-" lines that are immediately before
+       # the "+" block. That is, we construct this patch:
+       #
+       #    @@ -10,4 +10,5 @@
+       #     context before
+       #    +new 1
+       #     old 1
+       #     old 2
+       #     context after
+       #
+       # But we do *not* treat "-" lines that are *un*staged in a special
+       # way.
+       #
+       # With this asymmetry it is possible to stage the change
+       # "old 1" -> "new 1" directly, and to stage the change
+       # "old 2" -> "new 2" by first staging the entire hunk and
+       # then unstaging the change "old 1" -> "new 1".
+
+       # This is non-empty if and only if we are _staging_ changes;
+       # then it accumulates the consecutive "-" lines (after converting
+       # them to context lines) in order to be moved after the "+" change
+       # line.
+       set pre_context {}
+
+       set n 0
+       set i_l [$ui_diff index "$i_l + 1 lines"]
+       set patch {}
+       while {[$ui_diff compare $i_l < "end - 1 chars"] &&
+              [$ui_diff get $i_l "$i_l + 2 chars"] ne {@@}} {
+               set next_l [$ui_diff index "$i_l + 1 lines"]
+               set c1 [$ui_diff get $i_l]
+               if {[$ui_diff compare $i_l <= $the_l] &&
+                   [$ui_diff compare $the_l < $next_l]} {
+                       # the line to stage/unstage
+                       set ln [$ui_diff get $i_l $next_l]
+                       if {$c1 eq {-}} {
+                               set n [expr $n+1]
+                               set patch "$patch$pre_context$ln"
+                       } else {
+                               set patch "$patch$ln$pre_context"
+                       }
+                       set pre_context {}
+               } elseif {$c1 ne {-} && $c1 ne {+}} {
+                       # context line
+                       set ln [$ui_diff get $i_l $next_l]
+                       set patch "$patch$pre_context$ln"
+                       set n [expr $n+1]
+                       set pre_context {}
+               } elseif {$c1 eq $to_context} {
+                       # turn change line into context line
+                       set ln [$ui_diff get "$i_l + 1 chars" $next_l]
+                       if {$c1 eq {-}} {
+                               set pre_context "$pre_context $ln"
+                       } else {
+                               set patch "$patch $ln"
+                       }
+                       set n [expr $n+1]
+               }
+               set i_l $next_l
+       }
+       set patch "@@ -$hln,$n +$hln,[eval expr $n $sign 1] @@\n$patch"
+
+       if {[catch {
+               set p [eval git_write $apply_cmd]
+               fconfigure $p -translation binary -encoding binary
+               puts -nonewline $p $current_diff_header
+               puts -nonewline $p $patch
+               close $p} err]} {
+               error_popup [append $failed_msg "\n\n$err"]
+       }
+
+       unlock_index
+}