git-gui: Use git diff --submodule when available

diff --git a/lib/diff.tcl b/lib/diff.tcl
index 925b3f56c1c23cc5e0c2b270b9f7e160013c9009..cd5b74c7280de3471dca9669c80cd2e105cb46bd 100644 (file)
--- a/lib/diff.tcl
+++ b/lib/diff.tcl
@@ -255,7 +255,7 @@ proc show_other_diff {path w m cont_info} {
 
 proc start_show_diff {cont_info {add_opts {}}} {
        global file_states file_lists
-       global is_3way_diff diff_active repo_config
+       global is_3way_diff is_submodule_diff diff_active repo_config
        global ui_diff ui_index ui_workdir
        global current_diff_path current_diff_side current_diff_header
 
@@ -265,6 +265,7 @@ proc start_show_diff {cont_info {add_opts {}}} {
        set s $file_states($path)
        set m [lindex $s 0]
        set is_3way_diff 0
+       set is_submodule_diff 0
        set diff_active 1
        set current_diff_header {}
 
@@ -280,6 +281,15 @@ proc start_show_diff {cont_info {add_opts {}}} {
                }
        }
 
+       if {[string match {160000 *} [lindex $s 2]]
+        || [string match {160000 *} [lindex $s 3]]} {
+               set is_submodule_diff 1
+
+               if {[git-version >= "1.6.6"]} {
+                       lappend cmd --submodule
+               }
+       }
+
        lappend cmd -p
        lappend cmd --no-color
        if {$repo_config(gui.diffcontext) >= 1} {
@@ -295,6 +305,14 @@ proc start_show_diff {cont_info {add_opts {}}} {
                lappend cmd $path
        }
 
+       if {$is_submodule_diff && [git-version < "1.6.6"]} {
+               if {$w eq $ui_index} {
+                       set cmd [list submodule summary --cached -- $path]
+               } else {
+                       set cmd [list submodule summary --files -- $path]
+               }
+       }
+
        if {[catch {set fd [eval git_read --nice $cmd]} err]} {
                set diff_active 0
                unlock_index
@@ -312,7 +330,7 @@ proc start_show_diff {cont_info {add_opts {}}} {
 }
 
 proc read_diff {fd cont_info} {
-       global ui_diff diff_active
+       global ui_diff diff_active is_submodule_diff
        global is_3way_diff is_conflict_diff current_diff_header
        global current_diff_queue
        global diff_empty_count
@@ -374,6 +392,25 @@ proc read_diff {fd cont_info} {
                                set tags {}
                        }
                        }
+               } elseif {$is_submodule_diff} {
+                       if {$line == ""} continue
+                       if {[regexp {^Submodule } $line]} {
+                               set tags d_@
+                       } elseif {[regexp {^\* } $line]} {
+                               set line [string replace $line 0 1 {Submodule }]
+                               set tags d_@
+                       } else {
+                               set op [string range $line 0 2]
+                               switch -- $op {
+                               {  <} {set tags d_-}
+                               {  >} {set tags d_+}
+                               {  W} {set tags {}}
+                               default {
+                                       puts "error: Unhandled submodule diff marker: {$op}"
+                                       set tags {}
+                               }
+                               }
+                       }
                } else {
                        set op [string index $line 0]
                        switch -- $op {
@@ -636,6 +673,7 @@ proc apply_line {x y} {
                }
                set i_l $next_l
        }
+       set patch "$patch$pre_context"
        set patch "@@ -$hln,$n +$hln,[eval expr $n $sign 1] @@\n$patch"
 
        if {[catch {