fix(macos): scale menu item icon height to 18, closes #584 (#590)

* fix(macos): scale menu item icon height to 18, closes #584

* fix imports and get_size order

* changefile

Co-authored-by: amrbashir <amr.bashir2015@gmail.com>

.changes/macos-menu-item-dpi.md

@@ -0,0 +1,5 @@
+---
+"tao": patch
+---
+
+On macOS, scale menu item icons height to 18.

src/platform_impl/macos/menu.rs

@@ -5,7 +5,7 @@
 use cocoa::{
   appkit::{NSApp, NSApplication, NSButton, NSEventModifierFlags, NSImage, NSMenu, NSMenuItem},
   base::{id, nil, selector},
-  foundation::{NSAutoreleasePool, NSData, NSString},
+  foundation::{NSAutoreleasePool, NSData, NSSize, NSString},
 };
 use objc::{
   declare::ClassDecl,
@@ -85,16 +85,22 @@ impl MenuItemAttributes {
   }
 
   pub fn set_icon(&mut self, icon: Icon) {
-    unsafe {
-      let icon = icon.inner.to_png();
+    let (width, height) = icon.inner.get_size();
+    let icon = icon.inner.to_png();
+
+    let icon_height: f64 = 18.0;
+    let icon_width: f64 = (width as f64) / (height as f64 / icon_height);
 
+    unsafe {
       let nsdata = NSData::dataWithBytes_length_(
         nil,
         icon.as_ptr() as *const std::os::raw::c_void,
         icon.len() as u64,
       );
 
       let nsimage = NSImage::initWithData_(NSImage::alloc(nil), nsdata);
+      let new_size = NSSize::new(icon_width, icon_height);
+      let _: () = msg_send![nsimage, setSize: new_size];
       let _: () = msg_send![self.1, setImage: nsimage];
     }
   }