From 324dd5fa86d9c20a69e812b63cc0aba4ced9cab7 Mon Sep 17 00:00:00 2001
From: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
Date: Fri, 5 Jan 2024 11:53:47 +0100
Subject: [PATCH] On macOS, reported shifted key with shift+Ctrl/Cmd

Fixes #3078.
---
 CHANGELOG.md                     |  1 +
 src/platform_impl/macos/event.rs | 23 ++++++++++++++++++++---
 2 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8c94f9caca..f1da5bfb44 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,6 +14,7 @@ Unreleased` header.
 - On X11, fix `NotSupported` error not propagated when creating event loop.
 - On Wayland, fix resize not issued when scale changes
 - On X11 and Wayland, fix arrow up on keypad reported as `ArrowLeft`.
+- On macOS, report correct logical key when Ctrl or Cmd is pressed.
 
 # 0.29.8
 
diff --git a/src/platform_impl/macos/event.rs b/src/platform_impl/macos/event.rs
index cdd79297ec..77d527eb54 100644
--- a/src/platform_impl/macos/event.rs
+++ b/src/platform_impl/macos/event.rs
@@ -39,6 +39,7 @@ impl KeyEventExtModifierSupplement for KeyEvent {
     }
 }
 
+/// Ignores ALL modifiers.
 pub fn get_modifierless_char(scancode: u16) -> Key {
     let mut string = [0; 16];
     let input_source;
@@ -97,6 +98,7 @@ pub fn get_modifierless_char(scancode: u16) -> Key {
     Key::Character(SmolStr::new(chars))
 }
 
+// Ignores all modifiers except for SHIFT (yes, even ALT is ignored).
 fn get_logical_key_char(ns_event: &NSEvent, modifierless_chars: &str) -> Key {
     let string = ns_event
         .charactersIgnoringModifiers()
@@ -126,6 +128,13 @@ pub(crate) fn create_key_event(
     let mut physical_key =
         key_override.unwrap_or_else(|| PhysicalKey::from_scancode(scancode as u32));
 
+    // NOTE: The logical key should heed both SHIFT and ALT if possible.
+    // For instance:
+    // * Pressing the A key: logical key should be "a"
+    // * Pressing SHIFT A: logical key should be "A"
+    // * Pressing CTRL SHIFT A: logical key should also be "A"
+    // This is not easy to tease out of `NSEvent`, but we do our best.
+
     let text_with_all_modifiers: Option<SmolStr> = if key_override.is_some() {
         None
     } else {
@@ -146,21 +155,29 @@ pub(crate) fn create_key_event(
 
     let key_from_code = code_to_key(physical_key, scancode);
     let (logical_key, key_without_modifiers) = if matches!(key_from_code, Key::Unidentified(_)) {
+        // `get_modifierless_char/key_without_modifiers` ignores ALL modifiers.
         let key_without_modifiers = get_modifierless_char(scancode);
 
         let modifiers = NSEvent::modifierFlags(ns_event);
         let has_ctrl = modifiers.contains(NSEventModifierFlags::NSControlKeyMask);
+        let has_cmd = modifiers.contains(NSEventModifierFlags::NSCommandKeyMask);
 
         let logical_key = match text_with_all_modifiers.as_ref() {
-            // Only checking for ctrl here, not checking for alt because we DO want to
+            // Only checking for ctrl and cmd here, not checking for alt because we DO want to
             // include its effect in the key. For example if -on the Germay layout- one
             // presses alt+8, the logical key should be "{"
             // Also not checking if this is a release event because then this issue would
             // still affect the key release.
-            Some(text) if !has_ctrl => Key::Character(text.clone()),
+            Some(text) if !has_ctrl && !has_cmd => {
+                // Character heeding both SHIFT and ALT.
+                Key::Character(text.clone())
+            }
+
             _ => match key_without_modifiers.as_ref() {
+                // Character heeding just SHIFT, ignoring ALT.
                 Key::Character(ch) => get_logical_key_char(ns_event, ch),
-                // Don't try to get text for events which likely don't have it.
+
+                // Character ignoring ALL modifiers.
                 _ => key_without_modifiers.clone(),
             },
         };