git-gui: Show special diffs for complex conflict cases.

Add special handling for displaying diffs of modified/deleted,
and symlink/mode conflicts. Currently the display is completely
unusable for deciding how to resolve the conflict.

New display modes:

1) Deleted/Modified conflict: e.g.
	LOCAL: deleted
	REMOTE:
	[diff :1:$path :3:$path]

2) Conflict involving symlinks:
	LOCAL:
	[diff :1:$path :2:$path]
	REMOTE:
	[diff :1:$path :3:$path]

In order to be able to display multiple diffs, this
patch adds a queue of commands to call.

Signed-off-by: Alexander Gavrilov <angavrilov@gmail.com>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

diff --git a/lib/diff.tcl b/lib/diff.tcl
index 153437b18e15e31d310994df8e9f26cb563bfe2e..e2ed262fb3a794dcb6ed2a4b69f973cd6fe9f9c9 100644 (file)
--- a/lib/diff.tcl
+++ b/lib/diff.tcl
@@ -65,6 +65,7 @@ proc show_diff {path w {lno {}} {scroll_pos {}}} {
        global is_3way_diff diff_active repo_config
        global ui_diff ui_index ui_workdir
        global current_diff_path current_diff_side current_diff_header
+       global current_diff_queue
 
        if {$diff_active || ![lock_index read]} return
 
@@ -82,13 +83,69 @@ proc show_diff {path w {lno {}} {scroll_pos {}}} {
 
        set s $file_states($path)
        set m [lindex $s 0]
-       set is_3way_diff 0
-       set diff_active 1
        set current_diff_path $path
        set current_diff_side $w
-       set current_diff_header {}
+       set current_diff_queue {}
        ui_status [mc "Loading diff of %s..." [escape_path $path]]
 
+       if {[string first {U} $m] >= 0} {
+               merge_load_stages $path [list show_unmerged_diff $scroll_pos]
+       } elseif {$m eq {_O}} {
+               show_other_diff $path $w $m $scroll_pos
+       } else {
+               start_show_diff $scroll_pos
+       }
+}
+
+proc show_unmerged_diff {scroll_pos} {
+       global current_diff_path current_diff_side
+       global merge_stages ui_diff
+       global current_diff_queue
+
+       if {$merge_stages(2) eq {}} {
+               lappend current_diff_queue \
+                       [list "LOCAL: deleted\nREMOTE:\n" d======= \
+                           [list ":1:$current_diff_path" ":3:$current_diff_path"]]
+       } elseif {$merge_stages(3) eq {}} {
+               lappend current_diff_queue \
+                       [list "REMOTE: deleted\nLOCAL:\n" d======= \
+                           [list ":1:$current_diff_path" ":2:$current_diff_path"]]
+       } elseif {[lindex $merge_stages(1) 0] eq {120000}
+               || [lindex $merge_stages(2) 0] eq {120000}
+               || [lindex $merge_stages(3) 0] eq {120000}} {
+               lappend current_diff_queue \
+                       [list "LOCAL:\n" d======= \
+                           [list ":1:$current_diff_path" ":2:$current_diff_path"]]
+               lappend current_diff_queue \
+                       [list "REMOTE:\n" d======= \
+                           [list ":1:$current_diff_path" ":3:$current_diff_path"]]
+       } else {
+               start_show_diff $scroll_pos
+               return
+       }
+
+       advance_diff_queue $scroll_pos
+}
+
+proc advance_diff_queue {scroll_pos} {
+       global current_diff_queue ui_diff
+
+       set item [lindex $current_diff_queue 0]
+       set current_diff_queue [lrange $current_diff_queue 1 end]
+
+       $ui_diff conf -state normal
+       $ui_diff insert end [lindex $item 0] [lindex $item 1]
+       $ui_diff conf -state disabled
+
+       start_show_diff $scroll_pos [lindex $item 2]
+}
+
+proc show_other_diff {path w m scroll_pos} {
+       global file_states file_lists
+       global is_3way_diff diff_active repo_config
+       global ui_diff ui_index ui_workdir
+       global current_diff_path current_diff_side current_diff_header
+
        # - Git won't give us the diff, there's nothing to compare to!
        #
        if {$m eq {_O}} {
@@ -167,6 +224,22 @@ proc show_diff {path w {lno {}} {scroll_pos {}}} {
                ui_ready
                return
        }
+}
+
+proc start_show_diff {scroll_pos {add_opts {}}} {
+       global file_states file_lists
+       global is_3way_diff diff_active repo_config
+       global ui_diff ui_index ui_workdir
+       global current_diff_path current_diff_side current_diff_header
+
+       set path $current_diff_path
+       set w $current_diff_side
+
+       set s $file_states($path)
+       set m [lindex $s 0]
+       set is_3way_diff 0
+       set diff_active 1
+       set current_diff_header {}
 
        set cmd [list]
        if {$w eq $ui_index} {
@@ -188,8 +261,12 @@ proc show_diff {path w {lno {}} {scroll_pos {}}} {
        if {$w eq $ui_index} {
                lappend cmd [PARENT]
        }
-       lappend cmd --
-       lappend cmd $path
+       if {$add_opts ne {}} {
+               eval lappend cmd $add_opts
+       } else {
+               lappend cmd --
+               lappend cmd $path
+       }
 
        if {[catch {set fd [eval git_read --nice $cmd]} err]} {
                set diff_active 0
@@ -209,6 +286,7 @@ proc show_diff {path w {lno {}} {scroll_pos {}}} {
 proc read_diff {fd scroll_pos} {
        global ui_diff diff_active
        global is_3way_diff current_diff_header
+       global current_diff_queue
 
        $ui_diff conf -state normal
        while {[gets $fd line] >= 0} {
@@ -293,6 +371,12 @@ proc read_diff {fd scroll_pos} {
 
        if {[eof $fd]} {
                close $fd
+
+               if {$current_diff_queue ne {}} {
+                       advance_diff_queue $scroll_pos
+                       return
+               }
+
                set diff_active 0
                unlock_index
                if {$scroll_pos ne {}} {