Fix WinResize hook getting triggered during urgent event processing

WinResize hooks could be triggered during shell evaluation, leading
to any state potentially getting mutated after a shell evaluation
call.

src/client.cc

@@ -80,6 +80,7 @@ bool Client::is_ui_ok() const
 bool Client::process_pending_inputs()
 {
     const bool debug_keys = (bool)(context().options()["debug"].get<DebugFlags>() & DebugFlags::Keys);
+    m_window->run_resize_hook_ifn();
     // steal keys as we might receive new keys while handling them.
     Vector<Key, MemoryDomain::Client> keys = std::move(m_pending_keys);
     for (auto& key : keys)

src/window.cc

@@ -193,8 +193,17 @@ void Window::set_dimensions(DisplayCoord dimensions)
     if (m_dimensions != dimensions)
     {
         m_dimensions = dimensions;
-        run_hook_in_own_context(Hook::WinResize, format("{}.{}", dimensions.line,
-                                                    dimensions.column));
+        m_resize_hook_pending = true;
+    }
+}
+
+void Window::run_resize_hook_ifn()
+{
+    if (m_resize_hook_pending)
+    {
+        m_resize_hook_pending = false;
+        run_hook_in_own_context(Hook::WinResize,
+                                format("{}.{}", m_dimensions.line, m_dimensions.column));
     }
 }
 

src/window.hh

@@ -48,6 +48,8 @@ public:
     void set_client(Client* client) { m_client = client; }
 
     void clear_display_buffer();
+    void run_resize_hook_ifn();
+
 private:
     Window(const Window&) = delete;
 
@@ -66,6 +68,7 @@ private:
     DisplayBuffer m_display_buffer;
 
     Highlighters m_builtin_highlighters;
+    bool m_resize_hook_pending = false;
 
     struct Setup
     {