Support guioptions 'k' flag in MacVim, prevents unnecessary window resize

Adds support for native GVim's 'k' flag. Adding/removing tabs/scrollbars
and setting 'linespace'/'columnspace' would now cause the number of
lines and columns in the buffer change to keep the window size constant,
instead of the other way round of resizing the window to keep the view
size constant. This helps prevent the window from resizing itself
unncessarily, which could be especially annoying when the window is
pinned/maximized.

Manually setting 'lines'/'columns', going to full screen, dragging the
window corner to resize would still resize the window.

Also removed misc calls within MMWindowController.m that were setting
shouldResizeVimView. Those calls were already handled by native Vim's
gui.c's gui_set_shellsize so it's redundant.

Close #617

src/MacVim/MMBackend.h

@@ -105,6 +105,7 @@ extern NSTimeInterval MMBalloonEvalInternalDelay;
 - (BOOL)tabBarVisible;
 - (void)showTabBar:(BOOL)enable;
 - (void)setRows:(int)rows columns:(int)cols;
+- (void)resizeView;
 - (void)setWindowTitle:(char *)title;
 - (void)setDocumentFilename:(char *)filename;
 - (char *)browseForFileWithAttributes:(NSDictionary *)attr;

src/MacVim/MMBackend.m

@@ -836,6 +836,11 @@ extern GuiFont gui_mch_retain_font(GuiFont font);
     [self queueMessage:SetTextDimensionsMsgID data:data];
 }
 
+- (void)resizeView
+{
+    [self queueMessage:ResizeViewMsgID data:nil];
+}
+
 - (void)setWindowTitle:(char *)title
 {
     NSMutableData *data = [NSMutableData data];
@@ -1997,6 +2002,7 @@ extern GuiFont gui_mch_retain_font(GuiFont font);
 
         tabpage_move(idx);
     } else if (SetTextDimensionsMsgID == msgid || LiveResizeMsgID == msgid
+            || SetTextDimensionsNoResizeWindowMsgID == msgid
             || SetTextRowsMsgID == msgid || SetTextColumnsMsgID == msgid) {
         if (!data) return;
         const void *bytes = [data bytes];
@@ -2028,6 +2034,8 @@ extern GuiFont gui_mch_retain_font(GuiFont font);
         [self queueMessage:msgid data:d];
 
         gui_resize_shell(cols, rows);
+    } else if (ResizeViewMsgID == msgid) {
+        [self queueMessage:msgid data:data];
     } else if (ExecuteMenuMsgID == msgid) {
         NSDictionary *attrs = [NSDictionary dictionaryWithData:data];
         if (attrs) {

src/MacVim/MMVimController.m

@@ -574,6 +574,7 @@ static BOOL isUnsafeMessage(int msgid);
         [windowController showTabBar:NO];
         [self sendMessage:BackingPropertiesChangedMsgID data:nil];
     } else if (SetTextDimensionsMsgID == msgid || LiveResizeMsgID == msgid ||
+            SetTextDimensionsNoResizeWindowMsgID == msgid ||
             SetTextDimensionsReplyMsgID == msgid) {
         const void *bytes = [data bytes];
         int rows = *((int*)bytes);  bytes += sizeof(int);
@@ -583,11 +584,16 @@ static BOOL isUnsafeMessage(int msgid);
         // acknowledges it with a reply message.  When this happens the window
         // should not move (the frontend would already have moved the window).
         BOOL onScreen = SetTextDimensionsReplyMsgID!=msgid;
+        
+        BOOL keepGUISize = SetTextDimensionsNoResizeWindowMsgID == msgid;
 
         [windowController setTextDimensionsWithRows:rows
                                  columns:cols
                                   isLive:(LiveResizeMsgID==msgid)
+                            keepGUISize:keepGUISize
                             keepOnScreen:onScreen];
+    } else if (ResizeViewMsgID == msgid) {
+        [windowController resizeView];
     } else if (SetWindowTitleMsgID == msgid) {
         const void *bytes = [data bytes];
         int len = *((int*)bytes);  bytes += sizeof(int);

src/MacVim/MMVimView.h

@@ -55,6 +55,7 @@
 - (void)viewWillStartLiveResize;
 - (void)viewDidEndLiveResize;
 - (void)setFrameSize:(NSSize)size;
+- (void)setFrameSizeKeepGUISize:(NSSize)size;
 - (void)setFrame:(NSRect)frame;
 
 @end

src/MacVim/MMVimView.m

@@ -60,7 +60,7 @@ enum {
 - (NSSize)vimViewSizeForTextViewSize:(NSSize)textViewSize;
 - (NSRect)textViewRectForVimViewSize:(NSSize)contentSize;
 - (NSTabView *)tabView;
-- (void)frameSizeMayHaveChanged;
+- (void)frameSizeMayHaveChanged:(BOOL)keepGUISize;
 @end
 
 
@@ -610,14 +610,25 @@ enum {
     // row will result in the vim view holding more rows than the can fit
     // inside the window.)
     [super setFrameSize:size];
-    [self frameSizeMayHaveChanged];
+    [self frameSizeMayHaveChanged:NO];
+}
+
+- (void)setFrameSizeKeepGUISize:(NSSize)size
+{
+    // NOTE: Instead of only acting when a frame was resized, we do some
+    // updating each time a frame may be resized.  (At the moment, if we only
+    // respond to actual frame changes then typing ":set lines=1000" twice in a
+    // row will result in the vim view holding more rows than the can fit
+    // inside the window.)
+    [super setFrameSize:size];
+    [self frameSizeMayHaveChanged:YES];
 }
 
 - (void)setFrame:(NSRect)frame
 {
     // See comment in setFrameSize: above.
     [super setFrame:frame];
-    [self frameSizeMayHaveChanged];
+    [self frameSizeMayHaveChanged:NO];
 }
 
 @end // MMVimView
@@ -867,7 +878,7 @@ enum {
     return tabView;
 }
 
-- (void)frameSizeMayHaveChanged
+- (void)frameSizeMayHaveChanged:(BOOL)keepGUISize
 {
     // NOTE: Whenever a call is made that may have changed the frame size we
     // take the opportunity to make sure all subviews are in place and that the
@@ -903,7 +914,7 @@ enum {
     if (constrained[0] != rows || constrained[1] != cols) {
         NSData *data = [NSData dataWithBytes:constrained length:2*sizeof(int)];
         int msgid = [self inLiveResize] ? LiveResizeMsgID
-                                        : SetTextDimensionsMsgID;
+                                        : (keepGUISize ? SetTextDimensionsNoResizeWindowMsgID : SetTextDimensionsMsgID);
 
         ASLogDebug(@"Notify Vim that text dimensions changed from %dx%d to "
                    "%dx%d (%s)", cols, rows, constrained[1], constrained[0],

src/MacVim/MMWindowController.h

@@ -24,6 +24,7 @@
     BOOL                setupDone;
     BOOL                windowPresented;
     BOOL                shouldResizeVimView;
+    BOOL                shouldKeepGUISize;
     BOOL                shouldRestoreUserTopLeft;
     BOOL                shouldMaximizeWindow;
     int                 updateToolbarFlag;
@@ -59,7 +60,9 @@
 - (void)updateTabsWithData:(NSData *)data;
 - (void)selectTabWithIndex:(int)idx;
 - (void)setTextDimensionsWithRows:(int)rows columns:(int)cols isLive:(BOOL)live
+                      keepGUISize:(BOOL)keepGUISize
                      keepOnScreen:(BOOL)onScreen;
+- (void)resizeView;
 - (void)zoomWithRows:(int)rows columns:(int)cols state:(int)state;
 - (void)setTitle:(NSString *)title;
 - (void)setDocumentFilename:(NSString *)filename;

src/MacVim/MMWindowController.m

@@ -174,7 +174,7 @@
 
     [win setDelegate:self];
     [win setInitialFirstResponder:[vimView textView]];
-    
+
     if ([win styleMask] & NSWindowStyleMaskTexturedBackground) {
         // On Leopard, we want to have a textured window to have nice
         // looking tabs. But the textured window look implies rounded
@@ -381,6 +381,7 @@
 }
 
 - (void)setTextDimensionsWithRows:(int)rows columns:(int)cols isLive:(BOOL)live
+                      keepGUISize:(BOOL)keepGUISize
                      keepOnScreen:(BOOL)onScreen
 {
     ASLogDebug(@"setTextDimensionsWithRows:%d columns:%d isLive:%d "
@@ -399,7 +400,7 @@
 
     [vimView setDesiredRows:rows columns:cols];
 
-    if (setupDone && !live) {
+    if (setupDone && !live && !keepGUISize) {
         shouldResizeVimView = YES;
         keepOnScreen = onScreen;
     }
@@ -428,6 +429,15 @@
     }
 }
 
+- (void)resizeView
+{
+    if (setupDone)
+    {
+        shouldResizeVimView = YES;
+        shouldKeepGUISize = YES;
+    }
+}
+
 - (void)zoomWithRows:(int)rows columns:(int)cols state:(int)state
 {
     [self setTextDimensionsWithRows:rows
@@ -503,9 +513,6 @@
 - (BOOL)destroyScrollbarWithIdentifier:(int32_t)ident
 {
     BOOL scrollbarHidden = [vimView destroyScrollbarWithIdentifier:ident];   
-    shouldResizeVimView = shouldResizeVimView || scrollbarHidden;
-    shouldMaximizeWindow = shouldMaximizeWindow || scrollbarHidden;
-
     return scrollbarHidden;
 }
 
@@ -513,9 +520,6 @@
 {
     BOOL scrollbarToggled = [vimView showScrollbarWithIdentifier:ident
                                                            state:visible];
-    shouldResizeVimView = shouldResizeVimView || scrollbarToggled;
-    shouldMaximizeWindow = shouldMaximizeWindow || scrollbarToggled;
-
     return scrollbarToggled;
 }
 
@@ -600,7 +604,18 @@
                                   fullScreenWindow ? [fullScreenWindow frame].size :
                                   fullScreenEnabled ? desiredWindowSize :
                                   [self constrainContentSizeToScreenSize:[vimView desiredSize]]];
-            [vimView setFrameSize:contentSize];
+
+            // Setting 'guioptions+=k' will make shouldKeepGUISize true, which
+            // means avoid resizing the window. Instead, resize the view instead
+            // to keep the GUI window's size consistent.
+            bool avoidWindowResize = shouldKeepGUISize && !fullScreenEnabled;
+
+            if (!avoidWindowResize) {
+                [vimView setFrameSize:contentSize];
+            }
+            else {
+                [vimView setFrameSizeKeepGUISize:originalSize];
+            }
 
             if (fullScreenWindow) {
                 // NOTE! Don't mark the full-screen content view as needing an
@@ -613,12 +628,15 @@
                     [fullScreenWindow centerView];
                 }
             } else {
-                [self resizeWindowToFitContentSize:contentSize
+                if (!avoidWindowResize) {
-                                      keepOnScreen:keepOnScreen];
+                    [self resizeWindowToFitContentSize:contentSize
+                                          keepOnScreen:keepOnScreen];
+                }
             }
         }
 
         keepOnScreen = NO;
+        shouldKeepGUISize = NO;
     }
 }
 
@@ -657,7 +675,6 @@
 {
     if (vimView && [vimView textView]) {
         [[vimView textView] setLinespace:(float)linespace];
-        shouldMaximizeWindow = shouldResizeVimView = YES;
     }
 }
 
@@ -665,7 +682,6 @@
 {
     if (vimView && [vimView textView]) {
         [[vimView textView] setColumnspace:(float)columnspace];
-        shouldMaximizeWindow = shouldResizeVimView = YES;
     }
 }
 
@@ -1177,7 +1193,7 @@
             [[window animator] setAlphaValue:0];
         } completionHandler:^{
             [self maximizeWindow:fullScreenOptions];
-            
+
             // Fade in
             [NSAnimationContext runAnimationGroup:^(NSAnimationContext *context) {
                 [context setDuration:0.5*duration];
@@ -1196,7 +1212,7 @@
 
     // The separator should never be visible in fullscreen or split-screen.
     [decoratedWindow hideTablineSeparator:YES];
-  
+
     // ASSUMPTION: fullScreenEnabled always reflects the state of Vim's 'fu'.
     if (!fullScreenEnabled) {
         ASLogDebug(@"Full-screen out of sync, tell Vim to set 'fu'");
@@ -1298,7 +1314,7 @@
         // full-screen by moving the window out from Split View.
         [vimController sendMessage:BackingPropertiesChangedMsgID data:nil];
     }
-  
+
     [self updateTablineSeparator];
 }
 
@@ -1519,7 +1535,6 @@
         // The tabline separator was toggled so the content view must change
         // size.
         [self updateResizeConstraints];
-        shouldResizeVimView = YES;
     }
 }
 

src/MacVim/MacVim.h

@@ -176,8 +176,10 @@ enum {
     SetTextRowsMsgID,
     SetTextColumnsMsgID,
     SetTextDimensionsMsgID,
+    SetTextDimensionsNoResizeWindowMsgID,
     LiveResizeMsgID,
     SetTextDimensionsReplyMsgID,
+    ResizeViewMsgID,
     SetWindowTitleMsgID,
     ScrollWheelMsgID,
     MouseDownMsgID,

src/MacVim/MacVim.m

@@ -30,8 +30,10 @@ char *MessageStrings[] =
     "SetTextRowsMsgID",
     "SetTextColumnsMsgID",
     "SetTextDimensionsMsgID",
+    "SetTextDimensionsNoResizeWindowMsgID",
     "LiveResizeMsgID",
     "SetTextDimensionsReplyMsgID",
+    "ResizeViewMsgID",
     "SetWindowTitleMsgID",
     "ScrollWheelMsgID",
     "MouseDownMsgID",

src/MacVim/gui_macvim.m

@@ -1732,6 +1732,18 @@ gui_mch_set_shellsize(
 }
 
 
+/*
+ * Re-calculates size of the Vim view to fit within the window without having
+ * to resize the window. Usually happens after UI elements have changed (e.g.
+ * adding / removing a toolbar) when guioptions 'k' is set.
+ */
+    void
+gui_mch_resize_view()
+{
+    [[MMBackend sharedInstance] resizeView];
+}
+
+
 /*
  * Set the position of the top left corner of the window to the given
  * coordinates.

src/gui.c

@@ -1621,6 +1621,16 @@ gui_set_shellsize(
     }
 #endif
 
+#ifdef FEAT_GUI_MACVIM
+    if (!mustset && (vim_strchr(p_go, GO_KEEPWINSIZE) != NULL))
+    {
+	/* We don't want to resize the window, so instruct the GUI to resize
+	 * the view to be within the constraints of the current window's size */
+	gui_mch_resize_view();
+	return;
+    }
+#endif
+
     base_width = gui_get_base_width();
     base_height = gui_get_base_height();
     if (fit_to_display)

src/proto/gui_macvim.pro

@@ -174,6 +174,8 @@ gui_mch_set_shellsize(
     int		base_height,
     int		direction);
     void
+gui_mch_resize_view();
+    void
 gui_mch_set_sp_color(guicolor_T color);
     void
 gui_mch_set_text_area_pos(int x, int y, int w, int h);