overlays: improve key_table handling

This commit re-arranges the code so that an overlay can have a local
stack of key table activations; this allows copy_mode and search_mode
key tables to layer on top of the user's window level key tables.

Previously, we'd just stick the search_mode entry on top of the global
state, which worked, but had the undesirable side effect of hijacking
the Enter key when switching to another tab in the window.

refs: https://github.com/wez/wezterm/issues/993

wezterm-gui/src/termwindow/keyevent.rs

@@ -82,9 +82,7 @@ impl KeyTableState {
                 return Some((entry, Some(name)));
             }
         }
-        input_map
+        None
-            .lookup_key(key, mods, None)
-            .map(|entry| (entry, None))
     }
 
     pub fn did_process_key(&mut self) {
@@ -148,6 +146,32 @@ impl super::TermWindow {
         key.encode_win32_input_mode()
     }
 
+    fn lookup_key(
+        &mut self,
+        pane: &Rc<dyn Pane>,
+        keycode: &KeyCode,
+        mods: Modifiers,
+    ) -> Option<(KeyTableEntry, Option<String>)> {
+        if let Some(overlay) = self.pane_state(pane.pane_id()).overlay.as_mut() {
+            if let Some((entry, table_name)) =
+                overlay
+                    .key_table_state
+                    .lookup_key(&self.input_map, keycode, mods)
+            {
+                return Some((entry, table_name.map(|s| s.to_string())));
+            }
+        }
+        if let Some((entry, table_name)) =
+            self.key_table_state
+                .lookup_key(&self.input_map, keycode, mods)
+        {
+            return Some((entry, table_name.map(|s| s.to_string())));
+        }
+        self.input_map
+            .lookup_key(keycode, mods, None)
+            .map(|entry| (entry, None))
+    }
+
     fn process_key(
         &mut self,
         pane: &Rc<dyn Pane>,
@@ -180,11 +204,9 @@ impl super::TermWindow {
         }
 
         if is_down {
-            if let Some((entry, table_name)) = self.key_table_state.lookup_key(
+            if let Some((entry, table_name)) =
-                &self.input_map,
+                self.lookup_key(pane, &keycode, raw_modifiers | leader_mod)
-                &keycode,
+            {
-                raw_modifiers | leader_mod,
-            ) {
                 if self.config.debug_key_events {
                     log::info!(
                         "{}{:?} {:?} -> perform {:?}",

wezterm-gui/src/termwindow/mod.rs

@@ -161,7 +161,7 @@ pub struct SemanticZoneCache {
 
 pub struct OverlayState {
     pub pane: Rc<dyn Pane>,
-    saved_key_table_state: KeyTableState,
+    key_table_state: KeyTableState,
 }
 
 #[derive(Default)]
@@ -2272,8 +2272,17 @@ impl TermWindow {
                         );
                         self.assign_overlay_for_pane(pane.pane_id(), search);
                     }
-                    self.key_table_state
+                    self.pane_state(pane.pane_id())
-                        .activate("search_mode", None, replace_current, false);
+                        .overlay
+                        .as_mut()
+                        .map(|overlay| {
+                            overlay.key_table_state.activate(
+                                "search_mode",
+                                None,
+                                replace_current,
+                                false,
+                            );
+                        });
                 }
             }
             QuickSelect => {
@@ -2311,8 +2320,17 @@ impl TermWindow {
                         );
                         self.assign_overlay_for_pane(pane.pane_id(), copy);
                     }
-                    self.key_table_state
+                    self.pane_state(pane.pane_id())
-                        .activate("copy_mode", None, replace_current, false);
+                        .overlay
+                        .as_mut()
+                        .map(|overlay| {
+                            overlay.key_table_state.activate(
+                                "copy_mode",
+                                None,
+                                replace_current,
+                                false,
+                            );
+                        });
                 }
             }
             AdjustPaneSize(direction, amount) => {
@@ -2815,14 +2833,9 @@ impl TermWindow {
                 return;
             }
         }
-        let mut key_table = None;
         if let Some(overlay) = self.tab_state(tab_id).overlay.take() {
-            key_table.replace(overlay.saved_key_table_state);
             Mux::get().unwrap().remove_pane(overlay.pane.pane_id());
         }
-        if let Some(key_table) = key_table.take() {
-            self.key_table_state = key_table;
-        }
         if let Some(window) = self.window.as_ref() {
             window.invalidate();
         }
@@ -2833,7 +2846,6 @@ impl TermWindow {
     }
 
     fn cancel_overlay_for_pane(&mut self, pane_id: PaneId) {
-        let mut key_table = None;
         if let Some(overlay) = self.pane_state(pane_id).overlay.take() {
             // Ungh, when I built the CopyOverlay, its pane doesn't get
             // added to the mux and instead it reports the overlaid
@@ -2842,10 +2854,6 @@ impl TermWindow {
             if pane_id != overlay.pane.pane_id() {
                 Mux::get().unwrap().remove_pane(overlay.pane.pane_id());
             }
-            key_table.replace(overlay.saved_key_table_state);
-        }
-        if let Some(key_table) = key_table.take() {
-            self.key_table_state = key_table;
         }
         if let Some(window) = self.window.as_ref() {
             window.invalidate();
@@ -2860,7 +2868,7 @@ impl TermWindow {
         self.cancel_overlay_for_pane(pane_id);
         self.pane_state(pane_id).overlay.replace(OverlayState {
             pane,
-            saved_key_table_state: self.key_table_state.clone(),
+            key_table_state: KeyTableState::default(),
         });
         self.update_title();
     }
@@ -2869,7 +2877,7 @@ impl TermWindow {
         self.cancel_overlay_for_tab(tab_id, None);
         self.tab_state(tab_id).overlay.replace(OverlayState {
             pane: overlay,
-            saved_key_table_state: self.key_table_state.clone(),
+            key_table_state: KeyTableState::default(),
         });
         self.update_title();
     }