From 7a3bc5505f60fa16a34aac4fb209dbb4968db9bf Mon Sep 17 00:00:00 2001
From: Amr Bashir <amr.bashir2015@gmail.com>
Date: Tue, 1 Aug 2023 19:43:04 +0300
Subject: [PATCH] fix(windows): don't drop `Menu` or `MenuChild` inside menu
 proc (#81)

`Menu` or `MenuChild`  are not owned by the menu proc and so it shouldn't drop it, previously this was okay because the `Menu` or `MenuChild` used to be a wrapper around `Rc<RefCell>` but that was changed in the last release.
---
 .changes/destroy.md              |  5 +++++
 src/platform_impl/windows/mod.rs | 14 +-------------
 2 files changed, 6 insertions(+), 13 deletions(-)
 create mode 100644 .changes/destroy.md

diff --git a/.changes/destroy.md b/.changes/destroy.md
new file mode 100644
index 0000000..7fe4b4b
--- /dev/null
+++ b/.changes/destroy.md
@@ -0,0 +1,5 @@
+---
+"muda": "patch"
+---
+
+On Windows, fix `ContextMenu::detach_menu_subclass_from_hwnd` crashing and terminating the thread.
diff --git a/src/platform_impl/windows/mod.rs b/src/platform_impl/windows/mod.rs
index f8e3901..211ed73 100644
--- a/src/platform_impl/windows/mod.rs
+++ b/src/platform_impl/windows/mod.rs
@@ -36,7 +36,7 @@ use windows_sys::Win32::{
             MFS_CHECKED, MFS_DISABLED, MF_BYCOMMAND, MF_BYPOSITION, MF_CHECKED, MF_DISABLED,
             MF_ENABLED, MF_GRAYED, MF_POPUP, MF_SEPARATOR, MF_STRING, MF_UNCHECKED, MIIM_BITMAP,
             MIIM_STATE, MIIM_STRING, SW_HIDE, SW_MAXIMIZE, SW_MINIMIZE, TPM_LEFTALIGN, WM_CLOSE,
-            WM_COMMAND, WM_DESTROY,
+            WM_COMMAND,
         },
     },
 };
@@ -298,7 +298,6 @@ impl Menu {
             .ok_or(crate::Error::NotInitialized)?;
         self.hwnds.remove(index);
         unsafe {
-            SendMessageW(hwnd, WM_CLEAR_MENU_DATA, 0, 0);
             RemoveWindowSubclass(hwnd, Some(menu_subclass_proc), MENU_SUBCLASS_ID);
             SetMenu(hwnd, 0);
             DrawMenuBar(hwnd);
@@ -320,7 +319,6 @@ impl Menu {
 
     pub fn detach_menu_subclass_from_hwnd(&self, hwnd: isize) {
         unsafe {
-            SendMessageW(hwnd, WM_CLEAR_MENU_DATA, 0, 0);
             RemoveWindowSubclass(hwnd, Some(menu_subclass_proc), MENU_SUBCLASS_ID);
         }
     }
@@ -799,7 +797,6 @@ impl MenuChild {
 
     pub fn detach_menu_subclass_from_hwnd(&self, hwnd: isize) {
         unsafe {
-            SendMessageW(hwnd, WM_CLEAR_MENU_DATA, 0, 0);
             RemoveWindowSubclass(hwnd, Some(menu_subclass_proc), SUBMENU_SUBCLASS_ID);
         }
     }
@@ -898,7 +895,6 @@ fn create_icon_item_info(hbitmap: HBITMAP) -> MENUITEMINFOW {
 
 const MENU_SUBCLASS_ID: usize = 200;
 const SUBMENU_SUBCLASS_ID: usize = 201;
-const WM_CLEAR_MENU_DATA: u32 = 600;
 
 unsafe extern "system" fn menu_subclass_proc(
     hwnd: HWND,
@@ -909,14 +905,6 @@ unsafe extern "system" fn menu_subclass_proc(
     dwrefdata: usize,
 ) -> LRESULT {
     let mut ret = -1;
-    if msg == WM_DESTROY || msg == WM_CLEAR_MENU_DATA {
-        if uidsubclass == MENU_SUBCLASS_ID {
-            drop(Box::from_raw(dwrefdata as *mut Menu));
-        } else {
-            drop(Box::from_raw(dwrefdata as *mut MenuChild));
-        }
-    }
-
     if msg == WM_COMMAND {
         let id = util::LOWORD(wparam as _) as u32;
         let item = if uidsubclass == MENU_SUBCLASS_ID {