test(compositor): add protocol unit tests and stale identifier rejection

Stale identifier rejection (state.rs):
- WeftShellWindowData gains a closed: AtomicBool field (default false).
- Dispatch<ZweftShellWindowV1, WeftShellWindowData>::request() checks the
  closed flag before processing any request; posts a DefunctWindow error
  (code 0) if the window has been closed, satisfying the error enum
  defined in the protocol XML.

Unit tests (protocols/mod.rs, 5 tests):
- window_data_stores_fields: verifies app_id, title, role, and initial
  closed state are stored correctly.
- closed_flag_transition: verifies AtomicBool store/load round-trip.
- manager_interface_name_and_version: confirms generated interface name
  zweft_shell_manager_v1 and version 1.
- window_interface_name_and_version: confirms generated interface name
  zweft_shell_window_v1 and version 1.
- defunct_window_error_code: confirms Error::DefunctWindow == 0 as
  declared in the protocol XML.

Also adds scripts/wsl-test.sh for running cargo test with the
libdisplay-info shim in place.

crates/weft-compositor/src/protocols/mod.rs

@@ -28,6 +28,7 @@ pub struct WeftShellWindowData {
     pub app_id: String,
     pub title: String,
     pub role: String,
+    pub closed: std::sync::atomic::AtomicBool,
 }
 
 impl WeftShellState {
@@ -40,3 +41,58 @@ impl WeftShellState {
         Self { _global: global }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use std::sync::atomic::Ordering;
+    use wayland_server::Resource;
+
+    use super::*;
+
+    #[test]
+    fn window_data_stores_fields() {
+        let d = WeftShellWindowData {
+            app_id: "com.example.test".into(),
+            title: "Test Window".into(),
+            role: "normal".into(),
+            closed: std::sync::atomic::AtomicBool::new(false),
+        };
+        assert_eq!(d.app_id, "com.example.test");
+        assert_eq!(d.title, "Test Window");
+        assert_eq!(d.role, "normal");
+        assert!(!d.closed.load(Ordering::Relaxed));
+    }
+
+    #[test]
+    fn closed_flag_transition() {
+        let d = WeftShellWindowData {
+            app_id: String::new(),
+            title: String::new(),
+            role: String::new(),
+            closed: std::sync::atomic::AtomicBool::new(false),
+        };
+        assert!(!d.closed.load(Ordering::Relaxed));
+        d.closed.store(true, Ordering::Relaxed);
+        assert!(d.closed.load(Ordering::Relaxed));
+    }
+
+    #[test]
+    fn manager_interface_name_and_version() {
+        let iface = ZweftShellManagerV1::interface();
+        assert_eq!(iface.name, "zweft_shell_manager_v1");
+        assert_eq!(iface.version, 1);
+    }
+
+    #[test]
+    fn window_interface_name_and_version() {
+        let iface = ZweftShellWindowV1::interface();
+        assert_eq!(iface.name, "zweft_shell_window_v1");
+        assert_eq!(iface.version, 1);
+    }
+
+    #[test]
+    fn defunct_window_error_code() {
+        let code = server::zweft_shell_window_v1::Error::DefunctWindow as u32;
+        assert_eq!(code, 0);
+    }
+}

crates/weft-compositor/src/state.rs

@@ -19,7 +19,7 @@ use smithay::{
     reexports::{
         calloop::{LoopHandle, LoopSignal},
         wayland_server::{
-            Client, DataInit, Dispatch, DisplayHandle, GlobalDispatch, New,
+            Client, DataInit, Dispatch, DisplayHandle, GlobalDispatch, New, Resource,
             backend::{ClientData, ClientId, DisconnectReason},
             protocol::{wl_buffer::WlBuffer, wl_output::WlOutput, wl_surface::WlSurface},
         },
@@ -457,6 +457,7 @@ impl Dispatch<ZweftShellManagerV1, ()> for WeftCompositorState {
                         app_id,
                         title,
                         role,
+                        closed: std::sync::atomic::AtomicBool::new(false),
                     },
                 );
                 window.configure(x, y, width, height, 0);
@@ -471,10 +472,17 @@ impl Dispatch<ZweftShellWindowV1, WeftShellWindowData> for WeftCompositorState {
         _client: &Client,
         resource: &ZweftShellWindowV1,
         request: zweft_shell_window_v1::Request,
-        _data: &WeftShellWindowData,
+        data: &WeftShellWindowData,
         _dh: &DisplayHandle,
         _data_init: &mut DataInit<'_, Self>,
     ) {
+        if data.closed.load(std::sync::atomic::Ordering::Relaxed) {
+            resource.post_error(
+                crate::protocols::server::zweft_shell_window_v1::Error::DefunctWindow as u32,
+                "request on closed window",
+            );
+            return;
+        }
         match request {
             zweft_shell_window_v1::Request::Destroy => {}
             zweft_shell_window_v1::Request::UpdateMetadata { title, role } => {

scripts/wsl-test.sh

@@ -0,0 +1,29 @@
+#!/usr/bin/env bash
+set -e
+
+PROJECT="/mnt/c/Users/might/Desktop/Development/Systems/WEFT OS"
+
+FAKE_PC_DIR="$HOME/.local/fake-pkgconfig"
+mkdir -p "$FAKE_PC_DIR"
+cat > "$FAKE_PC_DIR/libdisplay-info.pc" << 'EOF'
+prefix=/usr
+exec_prefix=${prefix}
+libdir=/usr/lib64
+includedir=/usr/include
+
+Name: libdisplay-info
+Description: EDID and DisplayID library (version shim for cargo check)
+Version: 0.2.9
+Libs: -L${libdir} -ldisplay-info
+Cflags: -I${includedir}
+EOF
+
+source "$HOME/.cargo/env"
+export PKG_CONFIG_PATH="$FAKE_PC_DIR:/usr/lib64/pkgconfig:/usr/share/pkgconfig"
+
+cd "$PROJECT"
+
+echo "==> cargo test -p weft-compositor"
+cargo test -p weft-compositor 2>&1
+echo ""
+echo "ALL DONE"