git-gui: Correct is_MacOSX platform test.

Darwn based UNIX systems are not necessarily Mac OS X.  However the only
windowing system used by Tk that is Mac OS X is 'aqua', and only 'aqua'
exists on Mac OS X.  Therefore this is a more reliable test for the
Macintosh platform.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

1 files changed, 1 insertions, 3 deletions

diff --git a/git-gui b/git-gui
index 3e53fbd62..afd9ac026 100755
--- a/git-gui
+++ b/git-gui
@@ -1716,9 +1716,7 @@ unset filemask i
 
 proc is_MacOSX {} {
 	global tcl_platform tk_library
-	if {$tcl_platform(platform) eq {unix}
-		&& $tcl_platform(os) eq {Darwin}
-		&& [string match /Library/Frameworks/* $tk_library]} {
+	if {[tk windowingsystem] eq {aqua}} {
 		return 1
 	}
 	return 0