4 files changed, 36 insertions, 24 deletions
diff --git a/git-gui/lib/commit.tcl b/git-gui/lib/commit.tcl
index 11379f8ad3..208dc2817c 100644
--- a/git-gui/lib/commit.tcl
+++ b/git-gui/lib/commit.tcl
@@ -207,8 +207,17 @@ You must stage at least 1 file before you can commit.
 
 	# -- A message is required.
 	#
-	set msg [string trim [$ui_comm get 1.0 end]]
+	set msg [$ui_comm get 1.0 end]
+	# Strip trailing whitespace
 	regsub -all -line {[ \t\r]+$} $msg {} msg
+	# Strip comment lines
+	regsub -all {(^|\n)#[^\n]*} $msg {\1} msg
+	# Strip leading empty lines
+	regsub {^\n*} $msg {} msg
+	# Compress consecutive empty lines
+	regsub -all {\n{3,}} $msg "\n\n" msg
+	# Strip trailing empty line
+	regsub {\n\n$} $msg "\n" msg
 	if {$msg eq {}} {
 		error_popup [mc "Please supply a commit message.
 
diff --git a/git-gui/lib/console.tcl b/git-gui/lib/console.tcl
index bb6b9c889e..fafafb81f1 100644
--- a/git-gui/lib/console.tcl
+++ b/git-gui/lib/console.tcl
@@ -97,7 +97,7 @@ method exec {cmd {after {}}} {
 		lappend cmd 2>@1
 		set fd_f [_open_stdout_stderr $cmd]
 	}
-	fconfigure $fd_f -blocking 0 -translation binary
+	fconfigure $fd_f -blocking 0 -translation binary -encoding [encoding system]
 	fileevent $fd_f readable [cb _read $fd_f $after]
 }
 
diff --git a/git-gui/lib/diff.tcl b/git-gui/lib/diff.tcl
index 871ad488c2..d657bfec05 100644
--- a/git-gui/lib/diff.tcl
+++ b/git-gui/lib/diff.tcl
@@ -63,28 +63,17 @@ proc force_diff_encoding {enc} {
 }
 
 proc handle_empty_diff {} {
-	global current_diff_path file_states file_lists
-	global diff_empty_count
+	global current_diff_path file_states
+	global ui_diff
 
 	set path $current_diff_path
 	set s $file_states($path)
 	if {[lindex $s 0] ne {_M} || [has_textconv $path]} return
 
-	# Prevent infinite rescan loops
-	incr diff_empty_count
-	if {$diff_empty_count > 1} return
-
-	info_popup [mc "No differences detected.
-
-%s has no changes.
-
-The modification date of this file was updated by another application, but the content within the file was not changed.
-
-A rescan will be automatically started to find other files which may have the same state." [short_path $path]]
-
-	clear_diff
-	display_file $path __
-	rescan ui_ready 0
+	$ui_diff conf -state normal
+	$ui_diff insert end [mc "* No differences detected; stage the file to de-list it from Unstaged Changes.\n"] d_info
+	$ui_diff insert end [mc "* Click to find other files that may have the same state.\n"] d_rescan
+	$ui_diff conf -state disabled
 }
 
 proc show_diff {path w {lno {}} {scroll_pos {}} {callback {}}} {
@@ -387,7 +376,6 @@ proc read_diff {fd conflict_size cont_info} {
 	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
 
 	$ui_diff conf -state normal
 	while {[gets $fd line] >= 0} {
@@ -559,8 +547,6 @@ proc read_diff {fd conflict_size cont_info} {
 
 		if {[$ui_diff index end] eq {2.0}} {
 			handle_empty_diff
-		} else {
-			set diff_empty_count 0
 		}
 
 		set callback [lindex $cont_info 1]
diff --git a/git-gui/lib/mergetool.tcl b/git-gui/lib/mergetool.tcl
index e688b016ef..8b8c16b1d6 100644
--- a/git-gui/lib/mergetool.tcl
+++ b/git-gui/lib/mergetool.tcl
@@ -272,8 +272,25 @@ proc merge_resolve_tool2 {} {
 		}
 	}
 	default {
-		error_popup [mc "Unsupported merge tool '%s'" $tool]
-		return
+		set tool_cmd [get_config mergetool.$tool.cmd]
+		if {$tool_cmd ne {}} {
+			if {([string first {[} $tool_cmd] != -1) || ([string first {]} $tool_cmd] != -1)} {
+				error_popup [mc "Unable to process square brackets in \"mergetool.%s.cmd\" configuration option.
+
+Please remove the square brackets." $tool]
+				return
+			} else {
+				set cmdline {}
+				foreach command_part $tool_cmd {
+					lappend cmdline [subst -nobackslashes -nocommands $command_part]
+				}
+			}
+		} else {
+			error_popup [mc "Unsupported merge tool '%s'.
+
+To use this tool, configure \"mergetool.%s.cmd\" as shown in the git-config manual page." $tool $tool]
+			return
+		}
 	}
 	}