fix: macOS maximize button shouldn't be disabled just because the window is non-fullscreenable (#40895)

* fix: macOS maximize button shouldn't be disabled just because the window is non-fullscreenable

Co-authored-by: Tamás Zahola <[email protected]>

* add test

Co-authored-by: Tamás Zahola <[email protected]>

* fix test by enabling maximize button if `resizable && (maximizable || fullscreenable)` instead of `(resizable && maximizable) && fullscreenable`

Co-authored-by: Tamás Zahola <[email protected]>

---------

Co-authored-by: trop[bot] <37223003+trop[bot]@users.noreply.github.com>
Co-authored-by: Tamás Zahola <[email protected]>

shell/browser/native_window_mac.h

@@ -238,6 +238,8 @@ class NativeWindowMac : public NativeWindow,
   void InternalSetParentWindow(NativeWindow* parent, bool attach);
   void SetForwardMouseMessages(bool forward);
 
+  void UpdateZoomButton();
+
   ElectronNSWindow* window_;  // Weak ref, managed by widget_.
 
   ElectronNSWindowDelegate* __strong window_delegate_;

shell/browser/native_window_mac.mm

@@ -863,8 +863,7 @@ void NativeWindowMac::SetResizable(bool resizable) {
   // the maximize button and ensure fullscreenability matches user setting.
   SetCanResize(resizable);
   SetFullScreenable(was_fullscreenable);
-  [[window_ standardWindowButton:NSWindowZoomButton]
-      setEnabled:resizable ? was_fullscreenable : false];
+  UpdateZoomButton();
 }
 
 bool NativeWindowMac::IsResizable() {
@@ -892,19 +891,26 @@ bool NativeWindowMac::IsMinimizable() {
 
 void NativeWindowMac::SetMaximizable(bool maximizable) {
   maximizable_ = maximizable;
-  [[window_ standardWindowButton:NSWindowZoomButton] setEnabled:maximizable];
+  UpdateZoomButton();
 }
 
 bool NativeWindowMac::IsMaximizable() {
   return [[window_ standardWindowButton:NSWindowZoomButton] isEnabled];
 }
 
+void NativeWindowMac::UpdateZoomButton() {
+  [[window_ standardWindowButton:NSWindowZoomButton]
+      setEnabled:IsResizable() && (CanMaximize() || IsFullScreenable())];
+}
+
 void NativeWindowMac::SetFullScreenable(bool fullscreenable) {
   SetCollectionBehavior(fullscreenable,
                         NSWindowCollectionBehaviorFullScreenPrimary);
   // On EL Capitan this flag is required to hide fullscreen button.
   SetCollectionBehavior(!fullscreenable,
                         NSWindowCollectionBehaviorFullScreenAuxiliary);
+
+  UpdateZoomButton();
 }
 
 bool NativeWindowMac::IsFullScreenable() {

spec/api-browser-window-spec.ts

@@ -5622,6 +5622,19 @@ describe('BrowserWindow module', () => {
         expect(w2.isFullScreenable()).to.be.false('isFullScreenable');
         expect(w3.isFullScreenable()).to.be.false('isFullScreenable');
       });
+
+      it('does not disable maximize button if window is resizable', () => {
+        const w = new BrowserWindow({
+          resizable: true,
+          fullscreenable: false
+        });
+
+        expect(w.isMaximizable()).to.be.true('isMaximizable');
+
+        w.setResizable(false);
+
+        expect(w.isMaximizable()).to.be.false('isMaximizable');
+      });
     });
 
     ifdescribe(process.platform === 'darwin')('isHiddenInMissionControl state', () => {