Refactor macOS to use new objc2 features (#2465)

* Remove UnownedWindow::inner_rect

* Refactor custom view to use much less `unsafe`

The compiler fence is safe to get rid of now since `interpretKeyEvents` takes `&mut self`

* Refactor Window to use much less unsafe

* Refactor NSApplication usage to have much less unsafe

* Remove cocoa dependency

* Enable `deny(unsafe_op_in_unsafe_fn)` on macOS

Also re-enable clippy `let_unit_value` lint

* Remove #[macro_use] on macOS

* Refactor window delegate to use much less unsafe

src/platform_impl/macos/appkit/view.rs

@@ -1,7 +1,13 @@
-use objc2::foundation::{NSObject, NSRect};
-use objc2::{extern_class, extern_methods, ClassType};
+use std::ffi::c_void;
+use std::num::NonZeroIsize;
+use std::ptr;
 
-use super::{NSCursor, NSResponder};
+use objc2::foundation::{NSObject, NSPoint, NSRect};
+use objc2::rc::{Id, Shared};
+use objc2::runtime::Object;
+use objc2::{extern_class, extern_methods, msg_send_id, ClassType};
+
+use super::{NSCursor, NSResponder, NSTextInputContext};
 
 extern_class!(
     #[derive(Debug, PartialEq, Eq, Hash)]
@@ -13,16 +19,77 @@ extern_class!(
     }
 );
 
+// Documented as "Main Thread Only".
+// > generally thread safe, although operations on views such as creating,
+// > resizing, and moving should happen on the main thread.
+// <https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/CocoaFundamentals/AddingBehaviortoaCocoaProgram/AddingBehaviorCocoa.html#//apple_ref/doc/uid/TP40002974-CH5-SW47>
+//
+// > If you want to use a thread to draw to a view, bracket all drawing code
+// > between the lockFocusIfCanDraw and unlockFocus methods of NSView.
+// <https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/Multithreading/ThreadSafetySummary/ThreadSafetySummary.html#//apple_ref/doc/uid/10000057i-CH12-123351-BBCFIIEB>
+
 extern_methods!(
     /// Getter methods
     unsafe impl NSView {
+        #[sel(frame)]
+        pub fn frame(&self) -> NSRect;
+
         #[sel(bounds)]
         pub fn bounds(&self) -> NSRect;
+
+        pub fn inputContext(
+            &self,
+            // _mtm: MainThreadMarker,
+        ) -> Option<Id<NSTextInputContext, Shared>> {
+            unsafe { msg_send_id![self, inputContext] }
+        }
+
+        #[sel(visibleRect)]
+        pub fn visibleRect(&self) -> NSRect;
+
+        #[sel(hasMarkedText)]
+        pub fn hasMarkedText(&self) -> bool;
+
+        #[sel(convertPoint:fromView:)]
+        pub fn convertPoint_fromView(&self, point: NSPoint, view: Option<&NSView>) -> NSPoint;
     }
 
     unsafe impl NSView {
+        #[sel(setWantsBestResolutionOpenGLSurface:)]
+        pub fn setWantsBestResolutionOpenGLSurface(&self, value: bool);
+
+        #[sel(setWantsLayer:)]
+        pub fn setWantsLayer(&self, wants_layer: bool);
+
+        #[sel(setPostsFrameChangedNotifications:)]
+        pub fn setPostsFrameChangedNotifications(&mut self, value: bool);
+
+        #[sel(removeTrackingRect:)]
+        pub fn removeTrackingRect(&self, tag: NSTrackingRectTag);
+
+        #[sel(addTrackingRect:owner:userData:assumeInside:)]
+        unsafe fn inner_addTrackingRect(
+            &self,
+            rect: NSRect,
+            owner: &Object,
+            user_data: *mut c_void,
+            assume_inside: bool,
+        ) -> Option<NSTrackingRectTag>;
+
+        pub fn add_tracking_rect(&self, rect: NSRect, assume_inside: bool) -> NSTrackingRectTag {
+            // SAFETY: The user data is NULL, so it is valid
+            unsafe { self.inner_addTrackingRect(rect, self, ptr::null_mut(), assume_inside) }
+                .expect("failed creating tracking rect")
+        }
+
         #[sel(addCursorRect:cursor:)]
         // NSCursor safe to take by shared reference since it is already immutable
         pub fn addCursorRect(&self, rect: NSRect, cursor: &NSCursor);
+
+        #[sel(setHidden:)]
+        pub fn setHidden(&self, hidden: bool);
     }
 );
+
+/// <https://developer.apple.com/documentation/appkit/nstrackingrecttag?language=objc>
+pub type NSTrackingRectTag = NonZeroIsize; // NSInteger, but non-zero!