macosx: add multi-selection support to the playlist's revealItemInFinder (refs #6892)

(cherry picked from commit 3dd486c8fe49c25f6bca2f93333cdcb83312e2be)

modules/gui/macosx/playlist.m

@@ -820,23 +820,34 @@
 
 - (IBAction)revealItemInFinder:(id)sender
 {
-    playlist_item_t * p_item = [[o_outline_view itemAtRow:[o_outline_view selectedRow]] pointerValue];
-    NSMutableString * o_mrl = nil;
+    NSIndexSet * selectedRows = [o_outline_view selectedRowIndexes];
+    NSUInteger count = [selectedRows count];
+    NSUInteger indexes[count];
+    [selectedRows getIndexes:indexes maxCount:count inIndexRange:nil];
+
+    NSMutableString * o_mrl;
+    playlist_item_t *p_item;
+    for (NSUInteger i = 0; i < count; i++) {
+        p_item = [[o_outline_view itemAtRow:indexes[i]] pointerValue];
 
         if(! p_item || !p_item->p_input )
-        return;
+            continue;
 
-    char *psz_uri = decode_URI( input_item_GetURI( p_item->p_input ) );
-    if( psz_uri )
-        o_mrl = [NSMutableString stringWithUTF8String: psz_uri];
+        o_mrl = [[NSMutableString alloc] initWithFormat: @"%s", decode_URI( input_item_GetURI( p_item->p_input ))];
 
         /* perform some checks whether it is a file and if it is local at all... */
+        if ([o_mrl length] > 0)
+        {
             NSRange prefix_range = [o_mrl rangeOfString: @"file:"];
             if( prefix_range.location != NSNotFound )
                 [o_mrl deleteCharactersInRange: prefix_range];
 
             if( [o_mrl characterAtIndex:0] == '/' )
                 [[NSWorkspace sharedWorkspace] selectFile: o_mrl inFileViewerRootedAtPath: o_mrl];
+        }
+
+        [o_mrl release];
+    }
 }
 
 /* When called retrieves the selected outlineview row and plays that node or item */