From fec49fedb6b0af8c8bcd9dee567d9188f6d0d385 Mon Sep 17 00:00:00 2001
From: Diggory Hardy <git@dhardy.name>
Date: Fri, 24 Apr 2026 14:33:00 +0000
Subject: [PATCH 01/10] Move edit_x_coord to Common

---
 crates/kas-widgets/src/edit/editor.rs | 29 +++++++++++++--------------
 1 file changed, 14 insertions(+), 15 deletions(-)

diff --git a/crates/kas-widgets/src/edit/editor.rs b/crates/kas-widgets/src/edit/editor.rs
index 13d68662a..d21ffe131 100644
--- a/crates/kas-widgets/src/edit/editor.rs
+++ b/crates/kas-widgets/src/edit/editor.rs
@@ -74,6 +74,7 @@ pub struct Common {
     direction: Direction,
     wrap: bool,
     read_only: bool,
+    edit_x_coord: Option<f32>,
 }
 
 impl Common {
@@ -87,6 +88,7 @@ impl Common {
             direction: Direction::Auto,
             wrap,
             read_only: false,
+            edit_x_coord: None,
         }
     }
 
@@ -140,7 +142,6 @@ pub struct Part {
     highlight: highlight::Cache,
     text: String,
     selection: CursorRange,
-    edit_x_coord: Option<f32>,
     last_edit: Option<EditOp>,
     undo_stack: UndoStack<(String, CursorRange)>,
     has_key_focus: bool,
@@ -367,7 +368,6 @@ impl Default for Part {
             highlight: Default::default(),
             text: Default::default(),
             selection: Default::default(),
-            edit_x_coord: None,
             last_edit: Some(EditOp::Initial),
             undo_stack: UndoStack::new(),
             has_key_focus: false,
@@ -825,7 +825,7 @@ impl Part {
                     let selection = self.selection.to_range();
                     self.replace_range(selection.clone(), text);
                     self.selection.set_position(selection.start + text.len());
-                    self.edit_x_coord = None;
+                    common.edit_x_coord = None;
 
                     EventAction::Edit
                 } else {
@@ -898,7 +898,7 @@ impl Part {
                     self.current = CurrentAction::ImePreedit {
                         edit_range: edit_range.cast(),
                     };
-                    self.edit_x_coord = None;
+                    common.edit_x_coord = None;
                     return EventAction::Preedit;
                 }
                 Ime::Commit { text } => {
@@ -915,7 +915,7 @@ impl Part {
                     self.current = CurrentAction::ImePreedit {
                         edit_range: self.selection.to_range().cast(),
                     };
-                    self.edit_x_coord = None;
+                    common.edit_x_coord = None;
                     return EventAction::Edit;
                 }
                 Ime::DeleteSurrounding {
@@ -1052,7 +1052,7 @@ impl Part {
         if range != self.selection {
             self.selection = range;
             self.set_view_offset_from_cursor(cx);
-            self.edit_x_coord = None;
+            common.edit_x_coord = None;
             cx.redraw();
         }
         event_action
@@ -1338,7 +1338,7 @@ impl Part {
             // Avoid use of unused navigation keys (e.g. by ScrollComponent):
             Command::Left | Command::Right | Command::WordLeft | Command::WordRight => Action::None,
             Command::Up | Command::Down if multi_line => {
-                let x = match self.edit_x_coord {
+                let x = match common.edit_x_coord {
                     Some(x) => x,
                     None => self
                         .display
@@ -1391,7 +1391,7 @@ impl Part {
                     .next_back()
                     .map(|r| r.pos.into())
                     .unwrap_or(Vec2::ZERO);
-                if let Some(x) = self.edit_x_coord {
+                if let Some(x) = common.edit_x_coord {
                     v.0 = x;
                 }
                 // TODO: page height should be an input?
@@ -1497,13 +1497,13 @@ impl Part {
                 };
                 self.replace_range(range, s);
                 self.selection.set_position(index + s.len());
-                self.edit_x_coord = None;
+                common.edit_x_coord = None;
                 EventAction::Edit
             }
             Action::Delete(sel, _) => {
                 self.replace_range(sel.clone(), "");
                 self.selection.set_position(sel.start);
-                self.edit_x_coord = None;
+                common.edit_x_coord = None;
                 EventAction::Edit
             }
             Action::Move(index, x_coord) => {
@@ -1513,7 +1513,7 @@ impl Part {
                 } else {
                     self.set_primary(cx);
                 }
-                self.edit_x_coord = x_coord;
+                common.edit_x_coord = x_coord;
                 cx.redraw();
                 EventAction::Cursor
             }
@@ -1522,7 +1522,7 @@ impl Part {
                     if self.text.as_str() != text {
                         self.text = text.clone();
                         self.status = Status::New;
-                        self.edit_x_coord = None;
+                        common.edit_x_coord = None;
                     }
                     self.selection = *cursor;
                     EventAction::Edit
@@ -1645,7 +1645,7 @@ impl Editor {
 
         let len = self.as_str().len();
         self.part.selection.set_max_len(len);
-        self.part.edit_x_coord = None;
+        self.common.edit_x_coord = None;
         self.error_state = None;
     }
 
@@ -1662,7 +1662,6 @@ impl Editor {
         self.part
             .selection
             .set_position(selection.start + text.len());
-        self.part.edit_x_coord = None;
         self.error_state = None;
     }
 
@@ -1678,7 +1677,7 @@ impl Editor {
     /// guard.
     #[inline]
     pub fn set_cursor_range(&mut self, range: CursorRange) {
-        self.part.edit_x_coord = None;
+        self.common.edit_x_coord = None;
         self.part.selection = range;
     }
 

From 7c1a8afaa94d745403ed2ce23d0bfe08d3e2212f Mon Sep 17 00:00:00 2001
From: Diggory Hardy <git@dhardy.name>
Date: Sat, 25 Apr 2026 14:55:28 +0000
Subject: [PATCH 02/10] Move selection to Common

Note: translations will be needed to support multiple text parts
---
 crates/kas-widgets/src/edit/editor.rs | 177 +++++++++++++-------------
 1 file changed, 86 insertions(+), 91 deletions(-)

diff --git a/crates/kas-widgets/src/edit/editor.rs b/crates/kas-widgets/src/edit/editor.rs
index d21ffe131..8e26d9547 100644
--- a/crates/kas-widgets/src/edit/editor.rs
+++ b/crates/kas-widgets/src/edit/editor.rs
@@ -75,6 +75,7 @@ pub struct Common {
     wrap: bool,
     read_only: bool,
     edit_x_coord: Option<f32>,
+    selection: CursorRange,
 }
 
 impl Common {
@@ -89,6 +90,7 @@ impl Common {
             wrap,
             read_only: false,
             edit_x_coord: None,
+            selection: CursorRange::default(),
         }
     }
 
@@ -141,7 +143,6 @@ pub struct Part {
     display: TextDisplay,
     highlight: highlight::Cache,
     text: String,
-    selection: CursorRange,
     last_edit: Option<EditOp>,
     undo_stack: UndoStack<(String, CursorRange)>,
     has_key_focus: bool,
@@ -264,7 +265,7 @@ impl<H: Highlighter> Component<H> {
     pub fn with_text(mut self, text: impl ToString) -> Self {
         self.0.part = self.0.part.with_text(text);
         let index = if self.0.common.wrap { 0 } else { self.0.part.text.len() };
-        self.0.part.selection.set_position(index);
+        self.0.common.selection.set_position(index);
         self
     }
 
@@ -367,7 +368,6 @@ impl Default for Part {
             display: TextDisplay::default(),
             highlight: Default::default(),
             text: Default::default(),
-            selection: Default::default(),
             last_edit: Some(EditOp::Initial),
             undo_stack: UndoStack::new(),
             has_key_focus: false,
@@ -405,12 +405,6 @@ impl Part {
         self.display.text_is_rtl()
     }
 
-    /// Access the cursor index / selection range
-    #[inline]
-    pub fn cursor_range(&self) -> CursorRange {
-        self.selection
-    }
-
     /// Check whether the text is fully prepared and ready for usage
     #[inline]
     pub fn is_prepared(&self) -> bool {
@@ -523,7 +517,7 @@ impl Part {
 
         self.prepare_wrap(common);
         if self.current.is_ime_enabled() {
-            self.set_ime_cursor_area(cx);
+            self.set_ime_cursor_area(common, cx);
         }
     }
 
@@ -583,7 +577,7 @@ impl Part {
         self.prepare_runs(common, highlighter);
         if self.prepare_wrap(common) {
             cx.resize();
-            self.set_view_offset_from_cursor(cx);
+            self.set_view_offset_from_cursor(common, cx);
         }
         cx.redraw();
     }
@@ -622,7 +616,7 @@ impl Part {
         }
 
         let pos = self.rect.pos - offset;
-        let range: Range<u32> = self.selection.to_range().cast();
+        let range: Range<u32> = common.selection.to_range().cast();
 
         let color_tokens = self.highlight.color_tokens();
         let default_colors = format::Colors {
@@ -731,7 +725,7 @@ impl Part {
                 pos,
                 rect,
                 &self.display,
-                self.selection.cursor,
+                common.selection.cursor,
                 Some(common.colors.cursor),
             );
         }
@@ -768,19 +762,19 @@ impl Part {
                 // the latter. We must set before calling self.set_primary.
                 self.has_key_focus = true;
                 if source == FocusSource::Pointer {
-                    self.set_primary(cx);
+                    self.set_primary(common, cx);
                 }
 
                 return EventAction::Used;
             }
             Event::KeyFocus => {
                 self.has_key_focus = true;
-                self.set_view_offset_from_cursor(cx);
+                self.set_view_offset_from_cursor(common, cx);
 
                 return if self.current.is_none() {
                     let hint = Default::default();
                     let purpose = ImePurpose::Normal;
-                    let surrounding_text = self.ime_surrounding_text();
+                    let surrounding_text = self.ime_surrounding_text(common);
                     cx.replace_ime_focus(self.id.clone(), hint, purpose, surrounding_text);
                     EventAction::FocusGained
                 } else {
@@ -798,9 +792,9 @@ impl Part {
             }
             Event::LostSelFocus => {
                 // NOTE: we can assume that we will receive Ime::Disabled if IME is active
-                if !self.selection.is_empty() {
-                    self.save_undo_state(None);
-                    self.selection.clear_selection();
+                if !common.selection.is_empty() {
+                    self.save_undo_state(common, None);
+                    common.selection.clear_selection();
                 }
                 self.input_handler.stop_selecting();
                 cx.redraw();
@@ -809,7 +803,7 @@ impl Part {
             Event::Command(cmd, code) => match self.cmd_action(common, cx, cmd, code) {
                 Ok(action) => {
                     if matches!(action, EventAction::Cursor) {
-                        self.set_view_offset_from_cursor(cx);
+                        self.set_view_offset_from_cursor(common, cx);
                     }
                     return action;
                 }
@@ -819,12 +813,12 @@ impl Part {
                 if event.state == ElementState::Pressed && !common.read_only =>
             {
                 return if let Some(text) = &event.text {
-                    self.save_undo_state(Some(EditOp::KeyInput));
-                    self.cancel_selection_and_ime(cx);
+                    self.save_undo_state(common, Some(EditOp::KeyInput));
+                    self.cancel_selection_and_ime(common, cx);
 
-                    let selection = self.selection.to_range();
+                    let selection = common.selection.to_range();
                     self.replace_range(selection.clone(), text);
-                    self.selection.set_position(selection.start + text.len());
+                    common.selection.set_position(selection.start + text.len());
                     common.edit_x_coord = None;
 
                     EventAction::Edit
@@ -837,7 +831,7 @@ impl Part {
                         match self.cmd_action(common, cx, cmd, Some(event.physical_key)) {
                             Ok(action) => {
                                 if matches!(action, EventAction::Cursor) {
-                                    self.set_view_offset_from_cursor(cx);
+                                    self.set_view_offset_from_cursor(common, cx);
                                 }
                                 action
                             }
@@ -853,7 +847,7 @@ impl Part {
                     match self.current {
                         CurrentAction::None => {
                             self.current = CurrentAction::ImeStart;
-                            self.set_ime_cursor_area(cx);
+                            self.set_ime_cursor_area(common, cx);
                         }
                         CurrentAction::ImeStart | CurrentAction::ImePreedit { .. } => {
                             // already enabled
@@ -870,7 +864,7 @@ impl Part {
                     };
                 }
                 Ime::Disabled => {
-                    self.clear_ime();
+                    self.clear_ime(common);
                     return if !self.has_key_focus {
                         EventAction::FocusLost
                     } else {
@@ -878,9 +872,9 @@ impl Part {
                     };
                 }
                 Ime::Preedit { text, cursor } => {
-                    self.save_undo_state(None);
+                    self.save_undo_state(common, None);
                     let mut edit_range = match self.current.clone() {
-                        CurrentAction::ImeStart if cursor.is_some() => self.selection.to_range(),
+                        CurrentAction::ImeStart if cursor.is_some() => common.selection.to_range(),
                         CurrentAction::ImeStart => return EventAction::Used,
                         CurrentAction::ImePreedit { edit_range } => edit_range.cast(),
                         _ => return EventAction::Used,
@@ -889,10 +883,10 @@ impl Part {
                     self.replace_range(edit_range.clone(), text);
                     edit_range.end = edit_range.start + text.len();
                     if let Some((start, end)) = cursor {
-                        self.selection.anchor = edit_range.start + start;
-                        self.selection.cursor = edit_range.start + end;
+                        common.selection.anchor = edit_range.start + start;
+                        common.selection.cursor = edit_range.start + end;
                     } else {
-                        self.selection.set_position(edit_range.start + text.len());
+                        common.selection.set_position(edit_range.start + text.len());
                     }
 
                     self.current = CurrentAction::ImePreedit {
@@ -902,18 +896,18 @@ impl Part {
                     return EventAction::Preedit;
                 }
                 Ime::Commit { text } => {
-                    self.save_undo_state(Some(EditOp::Ime));
+                    self.save_undo_state(common, Some(EditOp::Ime));
                     let edit_range = match self.current.clone() {
-                        CurrentAction::ImeStart => self.selection.to_range(),
+                        CurrentAction::ImeStart => common.selection.to_range(),
                         CurrentAction::ImePreedit { edit_range } => edit_range.cast(),
                         _ => return EventAction::Used,
                     };
 
                     self.replace_range(edit_range.clone(), text);
-                    self.selection.set_position(edit_range.start + text.len());
+                    common.selection.set_position(edit_range.start + text.len());
 
                     self.current = CurrentAction::ImePreedit {
-                        edit_range: self.selection.to_range().cast(),
+                        edit_range: common.selection.to_range().cast(),
                     };
                     common.edit_x_coord = None;
                     return EventAction::Edit;
@@ -922,9 +916,9 @@ impl Part {
                     before_bytes,
                     after_bytes,
                 } => {
-                    self.save_undo_state(None);
+                    self.save_undo_state(common, None);
                     let edit_range = match self.current.clone() {
-                        CurrentAction::ImeStart => self.selection.to_range(),
+                        CurrentAction::ImeStart => common.selection.to_range(),
                         CurrentAction::ImePreedit { edit_range } => edit_range.cast(),
                         _ => return EventAction::Used,
                     };
@@ -934,7 +928,7 @@ impl Part {
                         let start = end - before_bytes;
                         if self.as_str().is_char_boundary(start) {
                             self.replace_range(start..end, "");
-                            self.selection.delete_range(start..end);
+                            common.selection.delete_range(start..end);
                         } else {
                             log::warn!("buggy IME tried to delete range not at char boundary");
                         }
@@ -950,7 +944,7 @@ impl Part {
                         }
                     }
 
-                    if let Some(text) = self.ime_surrounding_text() {
+                    if let Some(text) = self.ime_surrounding_text(common) {
                         cx.update_ime_surrounding_text(&self.id, text);
                     }
 
@@ -966,11 +960,11 @@ impl Part {
             Event::PressEnd { press, .. } if press.is_tertiary() => {
                 let rel_pos = (press.coord - self.rect().pos).cast();
                 let mut index = self.display.text_index_nearest(rel_pos);
-                self.cancel_selection_and_ime(cx);
+                self.cancel_selection_and_ime(common, cx);
                 self.request_key_focus(cx, FocusSource::Pointer);
 
                 if let Some(content) = cx.get_primary() {
-                    self.save_undo_state(Some(EditOp::Clipboard));
+                    self.save_undo_state(common, Some(EditOp::Clipboard));
 
                     let range = self.trim_paste(common.wrap, &content);
                     self.replace_range(index..index, &content[range.clone()]);
@@ -988,16 +982,16 @@ impl Part {
                     repeats,
                 } => {
                     if self.current.is_ime_enabled() {
-                        self.clear_ime();
+                        self.clear_ime(common);
                         cx.cancel_ime_focus(&self.id);
                     }
                     self.request_key_focus(cx, FocusSource::Pointer);
-                    self.save_undo_state(Some(EditOp::Cursor));
+                    self.save_undo_state(common, Some(EditOp::Cursor));
                     self.current = CurrentAction::Selection;
 
                     let rel_pos = (coord - self.rect().pos).cast();
                     let cursor = self.display.text_index_nearest(rel_pos);
-                    let anchor = if clear { cursor } else { self.selection.anchor };
+                    let anchor = if clear { cursor } else { common.selection.anchor };
 
                     let range = CursorRange::from(anchor..cursor);
                     if repeats > 1 {
@@ -1021,7 +1015,7 @@ impl Part {
 
                     TextInput::adjust_range(
                         self.text.as_str(),
-                        self.selection,
+                        common.selection,
                         index,
                         repeats,
                         Some(&|index| self.display.find_line(index).map(|r| r.1)),
@@ -1029,17 +1023,17 @@ impl Part {
                 }
                 TextInputAction::PressEnd { coord } => {
                     if self.current.is_ime_enabled() {
-                        self.clear_ime();
+                        self.clear_ime(common);
                         cx.cancel_ime_focus(&self.id);
                     }
-                    self.save_undo_state(Some(EditOp::Cursor));
+                    self.save_undo_state(common, Some(EditOp::Cursor));
                     if self.current == CurrentAction::Selection {
-                        self.set_primary(cx);
+                        self.set_primary(common, cx);
                     } else {
                         let rel_pos = (coord - self.rect().pos).cast();
                         let index = self.display.text_index_nearest(rel_pos);
-                        self.selection.cursor = index;
-                        self.selection.clear_selection();
+                        common.selection.cursor = index;
+                        common.selection.clear_selection();
                     }
                     self.current = CurrentAction::None;
 
@@ -1049,9 +1043,9 @@ impl Part {
             },
         };
 
-        if range != self.selection {
-            self.selection = range;
-            self.set_view_offset_from_cursor(cx);
+        if range != common.selection {
+            common.selection = range;
+            self.set_view_offset_from_cursor(common, cx);
             common.edit_x_coord = None;
             cx.redraw();
         }
@@ -1077,12 +1071,12 @@ impl Part {
     ///
     /// This should be called if e.g. key-input interrupts the current
     /// action.
-    fn cancel_selection_and_ime(&mut self, cx: &mut EventState) {
+    fn cancel_selection_and_ime(&mut self, common: &mut Common, cx: &mut EventState) {
         if self.current == CurrentAction::Selection {
             self.input_handler.stop_selecting();
             self.current = CurrentAction::None;
         } else if self.current.is_ime_enabled() {
-            self.clear_ime();
+            self.clear_ime(common);
             cx.cancel_ime_focus(&self.id);
         }
     }
@@ -1091,20 +1085,20 @@ impl Part {
     ///
     /// One should also call [`EventCx::cancel_ime_focus`] unless this is
     /// implied.
-    fn clear_ime(&mut self) {
+    fn clear_ime(&mut self, common: &mut Common) {
         if self.current.is_ime_enabled() {
             let action = std::mem::replace(&mut self.current, CurrentAction::None);
             if let CurrentAction::ImePreedit { edit_range } = action {
-                self.selection.set_position(edit_range.start.cast());
+                common.selection.set_position(edit_range.start.cast());
                 self.replace_range(edit_range.cast(), "");
             }
         }
     }
 
-    fn ime_surrounding_text(&self) -> Option<ImeSurroundingText> {
+    fn ime_surrounding_text(&self, common: &Common) -> Option<ImeSurroundingText> {
         const MAX_TEXT_BYTES: usize = ImeSurroundingText::MAX_TEXT_BYTES;
 
-        let sel_range = self.selection.to_range();
+        let sel_range = common.selection.to_range();
         let edit_range = match self.current.clone() {
             CurrentAction::ImePreedit { edit_range } => Some(edit_range.cast()),
             _ => None,
@@ -1145,9 +1139,9 @@ impl Part {
             text = self.as_str()[range].to_string();
         }
 
-        let cursor = self.selection.cursor.saturating_sub(start);
+        let cursor = common.selection.cursor.saturating_sub(start);
         // Terminology difference: our sel_index is called 'anchor'
-        let sel_index = self.selection.anchor.saturating_sub(start);
+        let sel_index = common.selection.anchor.saturating_sub(start);
         ImeSurroundingText::new(text, cursor, sel_index)
             .inspect_err(|err| {
                 // TODO: use Display for err not Debug
@@ -1157,13 +1151,13 @@ impl Part {
     }
 
     /// Call to set IME position only while IME is active
-    fn set_ime_cursor_area(&self, cx: &mut EventState) {
+    fn set_ime_cursor_area(&self, common: &Common, cx: &mut EventState) {
         if !self.is_prepared() {
             return;
         }
 
         let range = match self.current.clone() {
-            CurrentAction::ImeStart => self.selection.to_range(),
+            CurrentAction::ImeStart => common.selection.to_range(),
             CurrentAction::ImePreedit { edit_range } => edit_range.cast(),
             _ => return,
         };
@@ -1200,7 +1194,7 @@ impl Part {
     /// Call before an edit to (potentially) commit current state based on last_edit
     ///
     /// Call with [`None`] to force commit of any uncommitted changes.
-    fn save_undo_state(&mut self, edit: Option<EditOp>) {
+    fn save_undo_state(&mut self, common: &mut Common, edit: Option<EditOp>) {
         if let Some(op) = edit
             && op.try_merge(&mut self.last_edit)
         {
@@ -1209,7 +1203,7 @@ impl Part {
 
         self.last_edit = edit;
         self.undo_stack
-            .try_push((self.as_str().to_string(), self.selection));
+            .try_push((self.as_str().to_string(), common.selection));
     }
 
     /// Request key focus, if we don't have it or IME
@@ -1248,10 +1242,10 @@ impl Part {
         let editable = !common.read_only;
         let mut shift = cx.modifiers().shift_key();
         let mut buf = [0u8; 4];
-        let cursor = self.selection.cursor;
+        let cursor = common.selection.cursor;
         let len = self.as_str().len();
         let multi_line = common.wrap;
-        let selection = self.selection.to_range();
+        let selection = common.selection.to_range();
         let have_sel = selection.end > selection.start;
         let string;
 
@@ -1436,7 +1430,7 @@ impl Part {
                 Action::Delete(prev..cursor, EditOp::Delete)
             }
             Command::SelectAll => {
-                self.selection.anchor = 0;
+                common.selection.anchor = 0;
                 shift = true; // hack
                 Action::Move(len, None)
             }
@@ -1468,7 +1462,7 @@ impl Part {
         }
 
         if !matches!(action, Action::None) {
-            self.cancel_selection_and_ime(cx);
+            self.cancel_selection_and_ime(common, cx);
         }
 
         let edit_op = match action {
@@ -1477,12 +1471,12 @@ impl Part {
             Action::Activate | Action::UndoRedo(_) => None,
             Action::Insert(_, edit) | Action::Delete(_, edit) => Some(edit),
         };
-        self.save_undo_state(edit_op);
+        self.save_undo_state(common, edit_op);
 
         let action = match action {
             Action::None => unreachable!(),
             Action::Deselect => {
-                self.selection.clear_selection();
+                common.selection.clear_selection();
                 cx.redraw();
                 EventAction::Cursor
             }
@@ -1496,22 +1490,22 @@ impl Part {
                     index..index
                 };
                 self.replace_range(range, s);
-                self.selection.set_position(index + s.len());
+                common.selection.set_position(index + s.len());
                 common.edit_x_coord = None;
                 EventAction::Edit
             }
             Action::Delete(sel, _) => {
                 self.replace_range(sel.clone(), "");
-                self.selection.set_position(sel.start);
+                common.selection.set_position(sel.start);
                 common.edit_x_coord = None;
                 EventAction::Edit
             }
             Action::Move(index, x_coord) => {
-                self.selection.cursor = index;
+                common.selection.cursor = index;
                 if !shift {
-                    self.selection.clear_selection();
+                    common.selection.clear_selection();
                 } else {
-                    self.set_primary(cx);
+                    self.set_primary(common, cx);
                 }
                 common.edit_x_coord = x_coord;
                 cx.redraw();
@@ -1524,7 +1518,7 @@ impl Part {
                         self.status = Status::New;
                         common.edit_x_coord = None;
                     }
-                    self.selection = *cursor;
+                    common.selection = *cursor;
                     EventAction::Edit
                 } else {
                     EventAction::Used
@@ -1536,9 +1530,9 @@ impl Part {
     }
 
     /// Set primary clipboard (mouse buffer) contents from selection
-    fn set_primary(&self, cx: &mut EventCx) {
-        if self.has_key_focus && !self.selection.is_empty() && cx.has_primary() {
-            let range = self.selection.to_range();
+    fn set_primary(&self, common: &Common, cx: &mut EventCx) {
+        if self.has_key_focus && !common.selection.is_empty() && cx.has_primary() {
+            let range = common.selection.to_range();
             cx.set_primary(String::from(&self.as_str()[range]));
         }
     }
@@ -1548,8 +1542,8 @@ impl Part {
     /// It is assumed that the text has not changed.
     ///
     /// A redraw is assumed since the cursor moved.
-    fn set_view_offset_from_cursor(&mut self, cx: &mut EventCx) {
-        let cursor = self.selection.cursor;
+    fn set_view_offset_from_cursor(&mut self, common: &Common, cx: &mut EventCx) {
+        let cursor = common.selection.cursor;
         if self.is_prepared()
             && let Some(marker) = self.display.text_glyph_pos(cursor).next_back()
         {
@@ -1602,7 +1596,8 @@ impl Editor {
     /// [`Self::set_string`] to commit changes to the undo history.
     #[inline]
     pub fn pre_commit(&mut self) {
-        self.part.save_undo_state(Some(EditOp::Synthetic));
+        self.part
+            .save_undo_state(&mut self.common, Some(EditOp::Synthetic));
     }
 
     /// Clear text contents and undo history
@@ -1638,13 +1633,13 @@ impl Editor {
             return; // no change
         }
 
-        self.part.cancel_selection_and_ime(cx);
+        self.part.cancel_selection_and_ime(&mut self.common, cx);
 
         self.part.text = text;
         self.part.require_reprepare();
 
         let len = self.as_str().len();
-        self.part.selection.set_max_len(len);
+        self.common.selection.set_max_len(len);
         self.common.edit_x_coord = None;
         self.error_state = None;
     }
@@ -1655,11 +1650,11 @@ impl Editor {
     /// guard.
     #[inline]
     pub fn replace_selected_text(&mut self, cx: &mut EventState, text: &str) {
-        self.part.cancel_selection_and_ime(cx);
+        self.part.cancel_selection_and_ime(&mut self.common, cx);
 
-        let selection = self.part.selection.to_range();
+        let selection = self.common.selection.to_range();
         self.part.replace_range(selection.clone(), text);
-        self.part
+        self.common
             .selection
             .set_position(selection.start + text.len());
         self.error_state = None;
@@ -1668,7 +1663,7 @@ impl Editor {
     /// Access the cursor index / selection range
     #[inline]
     pub fn cursor_range(&self) -> CursorRange {
-        self.part.selection
+        self.common.selection
     }
 
     /// Set the cursor index / range
@@ -1678,7 +1673,7 @@ impl Editor {
     #[inline]
     pub fn set_cursor_range(&mut self, range: CursorRange) {
         self.common.edit_x_coord = None;
-        self.part.selection = range;
+        self.common.selection = range;
     }
 
     /// Get whether this text-edit widget is read-only

From b25b75f242206e83521caafb392a98f4aae9fe95 Mon Sep 17 00:00:00 2001
From: Diggory Hardy <git@dhardy.name>
Date: Sat, 25 Apr 2026 15:40:49 +0000
Subject: [PATCH 03/10] Move last_edit, undo_stack to Common

---
 crates/kas-widgets/src/edit/editor.rs | 21 +++++++++++----------
 1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/crates/kas-widgets/src/edit/editor.rs b/crates/kas-widgets/src/edit/editor.rs
index 8e26d9547..a690735bc 100644
--- a/crates/kas-widgets/src/edit/editor.rs
+++ b/crates/kas-widgets/src/edit/editor.rs
@@ -76,6 +76,8 @@ pub struct Common {
     read_only: bool,
     edit_x_coord: Option<f32>,
     selection: CursorRange,
+    last_edit: Option<EditOp>,
+    undo_stack: UndoStack<(String, CursorRange)>,
 }
 
 impl Common {
@@ -91,6 +93,8 @@ impl Common {
             read_only: false,
             edit_x_coord: None,
             selection: CursorRange::default(),
+            last_edit: Some(EditOp::Initial),
+            undo_stack: UndoStack::new(),
         }
     }
 
@@ -143,8 +147,6 @@ pub struct Part {
     display: TextDisplay,
     highlight: highlight::Cache,
     text: String,
-    last_edit: Option<EditOp>,
-    undo_stack: UndoStack<(String, CursorRange)>,
     has_key_focus: bool,
     current: CurrentAction,
     input_handler: TextInput,
@@ -368,8 +370,6 @@ impl Default for Part {
             display: TextDisplay::default(),
             highlight: Default::default(),
             text: Default::default(),
-            last_edit: Some(EditOp::Initial),
-            undo_stack: UndoStack::new(),
             has_key_focus: false,
             current: CurrentAction::None,
             input_handler: Default::default(),
@@ -1196,13 +1196,14 @@ impl Part {
     /// Call with [`None`] to force commit of any uncommitted changes.
     fn save_undo_state(&mut self, common: &mut Common, edit: Option<EditOp>) {
         if let Some(op) = edit
-            && op.try_merge(&mut self.last_edit)
+            && op.try_merge(&mut common.last_edit)
         {
             return;
         }
 
-        self.last_edit = edit;
-        self.undo_stack
+        common.last_edit = edit;
+        common
+            .undo_stack
             .try_push((self.as_str().to_string(), common.selection));
     }
 
@@ -1512,7 +1513,7 @@ impl Part {
                 EventAction::Cursor
             }
             Action::UndoRedo(redo) => {
-                if let Some((text, cursor)) = self.undo_stack.undo_or_redo(redo) {
+                if let Some((text, cursor)) = common.undo_stack.undo_or_redo(redo) {
                     if self.text.as_str() != text {
                         self.text = text.clone();
                         self.status = Status::New;
@@ -1603,8 +1604,8 @@ impl Editor {
     /// Clear text contents and undo history
     #[inline]
     pub fn clear(&mut self, cx: &mut EventState) {
-        self.part.last_edit = Some(EditOp::Initial);
-        self.part.undo_stack.clear();
+        self.common.last_edit = Some(EditOp::Initial);
+        self.common.undo_stack.clear();
         self.set_string(cx, String::new());
     }
 

From 703ee01f64aba1f31f1a13674a070536b68c26d7 Mon Sep 17 00:00:00 2001
From: Diggory Hardy <git@dhardy.name>
Date: Sat, 25 Apr 2026 15:37:37 +0000
Subject: [PATCH 04/10] Move CurrentAction, input_handler to Common

---
 crates/kas-widgets/src/edit/editor.rs | 86 ++++++++++++++-------------
 1 file changed, 45 insertions(+), 41 deletions(-)

diff --git a/crates/kas-widgets/src/edit/editor.rs b/crates/kas-widgets/src/edit/editor.rs
index a690735bc..05687e043 100644
--- a/crates/kas-widgets/src/edit/editor.rs
+++ b/crates/kas-widgets/src/edit/editor.rs
@@ -78,6 +78,8 @@ pub struct Common {
     selection: CursorRange,
     last_edit: Option<EditOp>,
     undo_stack: UndoStack<(String, CursorRange)>,
+    current: CurrentAction,
+    input_handler: TextInput,
 }
 
 impl Common {
@@ -95,6 +97,8 @@ impl Common {
             selection: CursorRange::default(),
             last_edit: Some(EditOp::Initial),
             undo_stack: UndoStack::new(),
+            current: CurrentAction::None,
+            input_handler: Default::default(),
         }
     }
 
@@ -148,8 +152,6 @@ pub struct Part {
     highlight: highlight::Cache,
     text: String,
     has_key_focus: bool,
-    current: CurrentAction,
-    input_handler: TextInput,
 }
 
 /// Inner editor interface
@@ -265,6 +267,11 @@ impl<H: Highlighter> Component<H> {
     #[inline]
     #[must_use]
     pub fn with_text(mut self, text: impl ToString) -> Self {
+        debug_assert!(
+            self.0.common.current == CurrentAction::None
+                && !self.0.common.input_handler.is_selecting()
+        );
+
         self.0.part = self.0.part.with_text(text);
         let index = if self.0.common.wrap { 0 } else { self.0.part.text.len() };
         self.0.common.selection.set_position(index);
@@ -371,8 +378,6 @@ impl Default for Part {
             highlight: Default::default(),
             text: Default::default(),
             has_key_focus: false,
-            current: CurrentAction::None,
-            input_handler: Default::default(),
         }
     }
 }
@@ -384,7 +389,6 @@ impl Part {
     #[inline]
     #[must_use]
     pub fn with_text(mut self, text: impl ToString) -> Self {
-        debug_assert!(self.current == CurrentAction::None && !self.input_handler.is_selecting());
         let text = text.to_string();
         self.text = text;
         self
@@ -516,7 +520,7 @@ impl Part {
         self.rect = rect;
 
         self.prepare_wrap(common);
-        if self.current.is_ime_enabled() {
+        if common.current.is_ime_enabled() {
             self.set_ime_cursor_area(common, cx);
         }
     }
@@ -707,7 +711,7 @@ impl Part {
             draw.decorate_text(pos, rect, &self.display, decorations);
         }
 
-        if let CurrentAction::ImePreedit { edit_range } = self.current.clone() {
+        if let CurrentAction::ImePreedit { edit_range } = common.current.clone() {
             let tokens = [
                 Default::default(),
                 (edit_range.start, format::Decoration {
@@ -750,8 +754,8 @@ impl Part {
         let mut event_action = EventAction::Used;
         let range = match event {
             Event::NavFocus(source) if source == FocusSource::Key => {
-                if !self.input_handler.is_selecting() {
-                    self.request_key_focus(cx, source);
+                if !common.input_handler.is_selecting() {
+                    self.request_key_focus(common, cx, source);
                 }
                 return EventAction::Used;
             }
@@ -771,7 +775,7 @@ impl Part {
                 self.has_key_focus = true;
                 self.set_view_offset_from_cursor(common, cx);
 
-                return if self.current.is_none() {
+                return if common.current.is_none() {
                     let hint = Default::default();
                     let purpose = ImePurpose::Normal;
                     let surrounding_text = self.ime_surrounding_text(common);
@@ -784,7 +788,7 @@ impl Part {
             Event::LostKeyFocus => {
                 self.has_key_focus = false;
                 cx.redraw();
-                return if !self.current.is_ime_enabled() {
+                return if !common.current.is_ime_enabled() {
                     EventAction::FocusLost
                 } else {
                     EventAction::Used
@@ -796,7 +800,7 @@ impl Part {
                     self.save_undo_state(common, None);
                     common.selection.clear_selection();
                 }
-                self.input_handler.stop_selecting();
+                common.input_handler.stop_selecting();
                 cx.redraw();
                 return EventAction::Used;
             }
@@ -844,9 +848,9 @@ impl Part {
             }
             Event::Ime(ime) => match ime {
                 Ime::Enabled => {
-                    match self.current {
+                    match common.current {
                         CurrentAction::None => {
-                            self.current = CurrentAction::ImeStart;
+                            common.current = CurrentAction::ImeStart;
                             self.set_ime_cursor_area(common, cx);
                         }
                         CurrentAction::ImeStart | CurrentAction::ImePreedit { .. } => {
@@ -873,7 +877,7 @@ impl Part {
                 }
                 Ime::Preedit { text, cursor } => {
                     self.save_undo_state(common, None);
-                    let mut edit_range = match self.current.clone() {
+                    let mut edit_range = match common.current.clone() {
                         CurrentAction::ImeStart if cursor.is_some() => common.selection.to_range(),
                         CurrentAction::ImeStart => return EventAction::Used,
                         CurrentAction::ImePreedit { edit_range } => edit_range.cast(),
@@ -889,7 +893,7 @@ impl Part {
                         common.selection.set_position(edit_range.start + text.len());
                     }
 
-                    self.current = CurrentAction::ImePreedit {
+                    common.current = CurrentAction::ImePreedit {
                         edit_range: edit_range.cast(),
                     };
                     common.edit_x_coord = None;
@@ -897,7 +901,7 @@ impl Part {
                 }
                 Ime::Commit { text } => {
                     self.save_undo_state(common, Some(EditOp::Ime));
-                    let edit_range = match self.current.clone() {
+                    let edit_range = match common.current.clone() {
                         CurrentAction::ImeStart => common.selection.to_range(),
                         CurrentAction::ImePreedit { edit_range } => edit_range.cast(),
                         _ => return EventAction::Used,
@@ -906,7 +910,7 @@ impl Part {
                     self.replace_range(edit_range.clone(), text);
                     common.selection.set_position(edit_range.start + text.len());
 
-                    self.current = CurrentAction::ImePreedit {
+                    common.current = CurrentAction::ImePreedit {
                         edit_range: common.selection.to_range().cast(),
                     };
                     common.edit_x_coord = None;
@@ -917,7 +921,7 @@ impl Part {
                     after_bytes,
                 } => {
                     self.save_undo_state(common, None);
-                    let edit_range = match self.current.clone() {
+                    let edit_range = match common.current.clone() {
                         CurrentAction::ImeStart => common.selection.to_range(),
                         CurrentAction::ImePreedit { edit_range } => edit_range.cast(),
                         _ => return EventAction::Used,
@@ -961,7 +965,7 @@ impl Part {
                 let rel_pos = (press.coord - self.rect().pos).cast();
                 let mut index = self.display.text_index_nearest(rel_pos);
                 self.cancel_selection_and_ime(common, cx);
-                self.request_key_focus(cx, FocusSource::Pointer);
+                self.request_key_focus(common, cx, FocusSource::Pointer);
 
                 if let Some(content) = cx.get_primary() {
                     self.save_undo_state(common, Some(EditOp::Clipboard));
@@ -973,7 +977,7 @@ impl Part {
                 }
                 index.into()
             }
-            event => match self.input_handler.handle(cx, self.id.clone(), event) {
+            event => match common.input_handler.handle(cx, self.id.clone(), event) {
                 TextInputAction::Used => return EventAction::Used,
                 TextInputAction::Unused => return EventAction::Unused,
                 TextInputAction::PressStart {
@@ -981,13 +985,13 @@ impl Part {
                     clear,
                     repeats,
                 } => {
-                    if self.current.is_ime_enabled() {
+                    if common.current.is_ime_enabled() {
                         self.clear_ime(common);
                         cx.cancel_ime_focus(&self.id);
                     }
-                    self.request_key_focus(cx, FocusSource::Pointer);
+                    self.request_key_focus(common, cx, FocusSource::Pointer);
                     self.save_undo_state(common, Some(EditOp::Cursor));
-                    self.current = CurrentAction::Selection;
+                    common.current = CurrentAction::Selection;
 
                     let rel_pos = (coord - self.rect().pos).cast();
                     let cursor = self.display.text_index_nearest(rel_pos);
@@ -1006,7 +1010,7 @@ impl Part {
                     }
                 }
                 TextInputAction::PressMove { coord, repeats } => {
-                    if self.current != CurrentAction::Selection {
+                    if common.current != CurrentAction::Selection {
                         return EventAction::Used;
                     }
 
@@ -1022,12 +1026,12 @@ impl Part {
                     )
                 }
                 TextInputAction::PressEnd { coord } => {
-                    if self.current.is_ime_enabled() {
+                    if common.current.is_ime_enabled() {
                         self.clear_ime(common);
                         cx.cancel_ime_focus(&self.id);
                     }
                     self.save_undo_state(common, Some(EditOp::Cursor));
-                    if self.current == CurrentAction::Selection {
+                    if common.current == CurrentAction::Selection {
                         self.set_primary(common, cx);
                     } else {
                         let rel_pos = (coord - self.rect().pos).cast();
@@ -1035,9 +1039,9 @@ impl Part {
                         common.selection.cursor = index;
                         common.selection.clear_selection();
                     }
-                    self.current = CurrentAction::None;
+                    common.current = CurrentAction::None;
 
-                    self.request_key_focus(cx, FocusSource::Pointer);
+                    self.request_key_focus(common, cx, FocusSource::Pointer);
                     return EventAction::Used;
                 }
             },
@@ -1072,10 +1076,10 @@ impl Part {
     /// This should be called if e.g. key-input interrupts the current
     /// action.
     fn cancel_selection_and_ime(&mut self, common: &mut Common, cx: &mut EventState) {
-        if self.current == CurrentAction::Selection {
-            self.input_handler.stop_selecting();
-            self.current = CurrentAction::None;
-        } else if self.current.is_ime_enabled() {
+        if common.current == CurrentAction::Selection {
+            common.input_handler.stop_selecting();
+            common.current = CurrentAction::None;
+        } else if common.current.is_ime_enabled() {
             self.clear_ime(common);
             cx.cancel_ime_focus(&self.id);
         }
@@ -1086,8 +1090,8 @@ impl Part {
     /// One should also call [`EventCx::cancel_ime_focus`] unless this is
     /// implied.
     fn clear_ime(&mut self, common: &mut Common) {
-        if self.current.is_ime_enabled() {
-            let action = std::mem::replace(&mut self.current, CurrentAction::None);
+        if common.current.is_ime_enabled() {
+            let action = std::mem::replace(&mut common.current, CurrentAction::None);
             if let CurrentAction::ImePreedit { edit_range } = action {
                 common.selection.set_position(edit_range.start.cast());
                 self.replace_range(edit_range.cast(), "");
@@ -1099,7 +1103,7 @@ impl Part {
         const MAX_TEXT_BYTES: usize = ImeSurroundingText::MAX_TEXT_BYTES;
 
         let sel_range = common.selection.to_range();
-        let edit_range = match self.current.clone() {
+        let edit_range = match common.current.clone() {
             CurrentAction::ImePreedit { edit_range } => Some(edit_range.cast()),
             _ => None,
         };
@@ -1156,7 +1160,7 @@ impl Part {
             return;
         }
 
-        let range = match self.current.clone() {
+        let range = match common.current.clone() {
             CurrentAction::ImeStart => common.selection.to_range(),
             CurrentAction::ImePreedit { edit_range } => edit_range.cast(),
             _ => return,
@@ -1208,8 +1212,8 @@ impl Part {
     }
 
     /// Request key focus, if we don't have it or IME
-    fn request_key_focus(&self, cx: &mut EventCx, source: FocusSource) {
-        if !self.has_key_focus && !self.current.is_ime_enabled() {
+    fn request_key_focus(&self, common: &Common, cx: &mut EventCx, source: FocusSource) {
+        if !self.has_key_focus && !common.current.is_ime_enabled() {
             cx.request_key_focus(self.id.clone(), source);
         }
     }
@@ -1459,7 +1463,7 @@ impl Part {
         // We can receive some commands without key focus as a result of
         // selection focus. Request focus on edit actions (like Command::Cut).
         if !matches!(action, Action::None | Action::Deselect) {
-            self.request_key_focus(cx, FocusSource::Synthetic);
+            self.request_key_focus(common, cx, FocusSource::Synthetic);
         }
 
         if !matches!(action, Action::None) {
@@ -1700,7 +1704,7 @@ impl Editor {
     /// This is true when the widget is has keyboard or IME focus.
     #[inline]
     pub fn has_input_focus(&self) -> bool {
-        self.part.has_key_focus || self.part.current.is_ime_enabled()
+        self.part.has_key_focus || self.common.current.is_ime_enabled()
     }
 
     /// Get whether the input state is erroneous

From f51bdd2674f99e8d778b4dccaafa695c856be011 Mon Sep 17 00:00:00 2001
From: Diggory Hardy <git@dhardy.name>
Date: Wed, 29 Apr 2026 10:44:42 +0000
Subject: [PATCH 05/10] Move has_key_focus to Common

---
 crates/kas-widgets/src/edit/editor.rs | 20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/crates/kas-widgets/src/edit/editor.rs b/crates/kas-widgets/src/edit/editor.rs
index 05687e043..13bcf1901 100644
--- a/crates/kas-widgets/src/edit/editor.rs
+++ b/crates/kas-widgets/src/edit/editor.rs
@@ -74,6 +74,7 @@ pub struct Common {
     direction: Direction,
     wrap: bool,
     read_only: bool,
+    has_key_focus: bool,
     edit_x_coord: Option<f32>,
     selection: CursorRange,
     last_edit: Option<EditOp>,
@@ -93,6 +94,7 @@ impl Common {
             direction: Direction::Auto,
             wrap,
             read_only: false,
+            has_key_focus: false,
             edit_x_coord: None,
             selection: CursorRange::default(),
             last_edit: Some(EditOp::Initial),
@@ -151,7 +153,6 @@ pub struct Part {
     display: TextDisplay,
     highlight: highlight::Cache,
     text: String,
-    has_key_focus: bool,
 }
 
 /// Inner editor interface
@@ -377,7 +378,6 @@ impl Default for Part {
             display: TextDisplay::default(),
             highlight: Default::default(),
             text: Default::default(),
-            has_key_focus: false,
         }
     }
 }
@@ -764,7 +764,7 @@ impl Part {
             Event::SelFocus(source) => {
                 // NOTE: sel focus implies key focus since we only request
                 // the latter. We must set before calling self.set_primary.
-                self.has_key_focus = true;
+                common.has_key_focus = true;
                 if source == FocusSource::Pointer {
                     self.set_primary(common, cx);
                 }
@@ -772,7 +772,7 @@ impl Part {
                 return EventAction::Used;
             }
             Event::KeyFocus => {
-                self.has_key_focus = true;
+                common.has_key_focus = true;
                 self.set_view_offset_from_cursor(common, cx);
 
                 return if common.current.is_none() {
@@ -786,7 +786,7 @@ impl Part {
                 };
             }
             Event::LostKeyFocus => {
-                self.has_key_focus = false;
+                common.has_key_focus = false;
                 cx.redraw();
                 return if !common.current.is_ime_enabled() {
                     EventAction::FocusLost
@@ -861,7 +861,7 @@ impl Part {
                             cx.cancel_ime_focus(&self.id);
                         }
                     }
-                    return if !self.has_key_focus {
+                    return if !common.has_key_focus {
                         EventAction::FocusGained
                     } else {
                         EventAction::Used
@@ -869,7 +869,7 @@ impl Part {
                 }
                 Ime::Disabled => {
                     self.clear_ime(common);
-                    return if !self.has_key_focus {
+                    return if !common.has_key_focus {
                         EventAction::FocusLost
                     } else {
                         EventAction::Used
@@ -1213,7 +1213,7 @@ impl Part {
 
     /// Request key focus, if we don't have it or IME
     fn request_key_focus(&self, common: &Common, cx: &mut EventCx, source: FocusSource) {
-        if !self.has_key_focus && !common.current.is_ime_enabled() {
+        if !common.has_key_focus && !common.current.is_ime_enabled() {
             cx.request_key_focus(self.id.clone(), source);
         }
     }
@@ -1536,7 +1536,7 @@ impl Part {
 
     /// Set primary clipboard (mouse buffer) contents from selection
     fn set_primary(&self, common: &Common, cx: &mut EventCx) {
-        if self.has_key_focus && !common.selection.is_empty() && cx.has_primary() {
+        if common.has_key_focus && !common.selection.is_empty() && cx.has_primary() {
             let range = common.selection.to_range();
             cx.set_primary(String::from(&self.as_str()[range]));
         }
@@ -1704,7 +1704,7 @@ impl Editor {
     /// This is true when the widget is has keyboard or IME focus.
     #[inline]
     pub fn has_input_focus(&self) -> bool {
-        self.part.has_key_focus || self.common.current.is_ime_enabled()
+        self.common.has_key_focus || self.common.current.is_ime_enabled()
     }
 
     /// Get whether the input state is erroneous

From d92a29fa86ff42671b3929ba6ea8871c7b3c7918 Mon Sep 17 00:00:00 2001
From: Diggory Hardy <git@dhardy.name>
Date: Wed, 29 Apr 2026 10:44:57 +0000
Subject: [PATCH 06/10] Move id from Part to Common

---
 crates/kas-widgets/src/edit/editor.rs | 50 +++++++++++----------------
 1 file changed, 21 insertions(+), 29 deletions(-)

diff --git a/crates/kas-widgets/src/edit/editor.rs b/crates/kas-widgets/src/edit/editor.rs
index 13bcf1901..e851e25fa 100644
--- a/crates/kas-widgets/src/edit/editor.rs
+++ b/crates/kas-widgets/src/edit/editor.rs
@@ -68,6 +68,8 @@ impl EventAction {
 /// Editor state common to all parts
 #[derive(Debug)]
 pub struct Common {
+    /// We store a copy of the widget id here, since the latter is inaccessible
+    id: Id,
     colors: SchemeColors,
     font: FontSelector,
     dpem: f32,
@@ -88,6 +90,7 @@ impl Common {
     #[inline]
     pub fn new(wrap: bool) -> Self {
         Common {
+            id: Id::default(),
             colors: SchemeColors::default(),
             font: FontSelector::default(),
             dpem: 16.0,
@@ -107,7 +110,8 @@ impl Common {
     /// Configure `Common` data
     #[inline]
     #[must_use]
-    pub fn configure(&mut self, cx: &SizeCx) -> Option<ActionResetStatus> {
+    pub fn configure(&mut self, cx: &SizeCx, id: Id) -> Option<ActionResetStatus> {
+        self.id = id;
         let font = cx.font(TextClass::Editor);
         let dpem = cx.dpem(TextClass::Editor);
         if font != self.font || dpem != self.dpem {
@@ -146,8 +150,6 @@ impl Common {
 /// methods: [`Self::content_size`], [`Self::draw_with_offset`].
 #[autoimpl(Debug)]
 pub struct Part {
-    // TODO(opt): id is duplicated here since macros don't let us put the core here
-    id: Id,
     rect: Rect,
     status: Status,
     display: TextDisplay,
@@ -288,7 +290,7 @@ impl<H: Highlighter> Component<H> {
     /// Configure component
     #[inline]
     pub fn configure(&mut self, cx: &mut ConfigCx, id: Id) {
-        if let Some(ActionResetStatus) = self.0.common.configure(&cx.size_cx()) {
+        if let Some(ActionResetStatus) = self.0.common.configure(&cx.size_cx(), id) {
             self.0.part.require_reprepare();
         }
         if let Some(_) = self.1.configure(cx) {
@@ -296,7 +298,6 @@ impl<H: Highlighter> Component<H> {
             self.0.part.require_reprepare();
         }
 
-        self.0.part.configure(id);
         self.0.part.prepare_runs(&mut self.0.common, &mut self.1);
     }
 
@@ -372,7 +373,6 @@ impl Default for Part {
     #[inline]
     fn default() -> Self {
         Part {
-            id: Id::default(),
             rect: Rect::ZERO,
             status: Status::New,
             display: TextDisplay::default(),
@@ -402,7 +402,7 @@ impl Part {
 
     /// Get the base directionality of the text
     ///
-    /// [`Self::configure`] should be called before this method.
+    /// [`Self::prepare_runs`] should be called before this method.
     #[inline]
     pub fn text_is_rtl(&self) -> bool {
         debug_assert!(self.status >= Status::ResizeLevelRuns);
@@ -421,19 +421,11 @@ impl Part {
         self.status = Status::New;
     }
 
-    /// Configure component
-    ///
-    /// [`Common::configure`] must be called before this method.
-    pub fn configure(&mut self, id: Id) {
-        self.id = id;
-    }
-
     /// Perform run-breaking and shaping
     ///
     /// This represents a high-level step of preparation required before
-    /// displaying text. After the `Part` is [configured](Self::configure), this
-    /// method should be called before any sizing operations. This will advance
-    /// the [`Status`] to [`Status::LevelRuns`].
+    /// displaying text. This method should be called before any sizing
+    /// operations. This will advance the [`Status`] to [`Status::LevelRuns`].
     /// This method must be called again after any edits to the `Part`'s text.
     #[inline]
     pub fn prepare_runs<H: Highlighter>(&mut self, common: &mut Common, highlighter: &mut H) {
@@ -724,7 +716,7 @@ impl Part {
             draw.decorate_text(pos, rect, &self.display, &tokens[r0..]);
         }
 
-        if !common.read_only && draw.ev_state().has_input_focus(&self.id) == Some(true) {
+        if !common.read_only && draw.ev_state().has_input_focus(&common.id) == Some(true) {
             draw.text_cursor(
                 pos,
                 rect,
@@ -779,7 +771,7 @@ impl Part {
                     let hint = Default::default();
                     let purpose = ImePurpose::Normal;
                     let surrounding_text = self.ime_surrounding_text(common);
-                    cx.replace_ime_focus(self.id.clone(), hint, purpose, surrounding_text);
+                    cx.replace_ime_focus(common.id.clone(), hint, purpose, surrounding_text);
                     EventAction::FocusGained
                 } else {
                     EventAction::Used
@@ -858,7 +850,7 @@ impl Part {
                         }
                         CurrentAction::Selection => {
                             // Do not interrupt selection
-                            cx.cancel_ime_focus(&self.id);
+                            cx.cancel_ime_focus(&common.id);
                         }
                     }
                     return if !common.has_key_focus {
@@ -949,14 +941,14 @@ impl Part {
                     }
 
                     if let Some(text) = self.ime_surrounding_text(common) {
-                        cx.update_ime_surrounding_text(&self.id, text);
+                        cx.update_ime_surrounding_text(&common.id, text);
                     }
 
                     return EventAction::Used;
                 }
             },
             Event::PressStart(press) if press.is_tertiary() => {
-                return match press.grab_click(self.id.clone()).complete(cx) {
+                return match press.grab_click(common.id.clone()).complete(cx) {
                     Unused => EventAction::Unused,
                     Used => EventAction::Used,
                 };
@@ -977,7 +969,7 @@ impl Part {
                 }
                 index.into()
             }
-            event => match common.input_handler.handle(cx, self.id.clone(), event) {
+            event => match common.input_handler.handle(cx, common.id.clone(), event) {
                 TextInputAction::Used => return EventAction::Used,
                 TextInputAction::Unused => return EventAction::Unused,
                 TextInputAction::PressStart {
@@ -987,7 +979,7 @@ impl Part {
                 } => {
                     if common.current.is_ime_enabled() {
                         self.clear_ime(common);
-                        cx.cancel_ime_focus(&self.id);
+                        cx.cancel_ime_focus(&common.id);
                     }
                     self.request_key_focus(common, cx, FocusSource::Pointer);
                     self.save_undo_state(common, Some(EditOp::Cursor));
@@ -1028,7 +1020,7 @@ impl Part {
                 TextInputAction::PressEnd { coord } => {
                     if common.current.is_ime_enabled() {
                         self.clear_ime(common);
-                        cx.cancel_ime_focus(&self.id);
+                        cx.cancel_ime_focus(&common.id);
                     }
                     self.save_undo_state(common, Some(EditOp::Cursor));
                     if common.current == CurrentAction::Selection {
@@ -1081,7 +1073,7 @@ impl Part {
             common.current = CurrentAction::None;
         } else if common.current.is_ime_enabled() {
             self.clear_ime(common);
-            cx.cancel_ime_focus(&self.id);
+            cx.cancel_ime_focus(&common.id);
         }
     }
 
@@ -1192,7 +1184,7 @@ impl Part {
             return;
         };
 
-        cx.set_ime_cursor_area(&self.id, rect + Offset::conv(self.rect.pos));
+        cx.set_ime_cursor_area(&common.id, rect + Offset::conv(self.rect.pos));
     }
 
     /// Call before an edit to (potentially) commit current state based on last_edit
@@ -1214,7 +1206,7 @@ impl Part {
     /// Request key focus, if we don't have it or IME
     fn request_key_focus(&self, common: &Common, cx: &mut EventCx, source: FocusSource) {
         if !common.has_key_focus && !common.current.is_ime_enabled() {
-            cx.request_key_focus(self.id.clone(), source);
+            cx.request_key_focus(common.id.clone(), source);
         }
     }
 
@@ -1565,7 +1557,7 @@ impl Editor {
     /// Get a reference to the widget's identifier
     #[inline]
     pub fn id_ref(&self) -> &Id {
-        &self.part.id
+        &self.common.id
     }
 
     /// Get the widget's identifier

From c9047cbb91d983fc4533accc9800bbc0f0ea817d Mon Sep 17 00:00:00 2001
From: Diggory Hardy <git@dhardy.name>
Date: Wed, 29 Apr 2026 10:52:47 +0000
Subject: [PATCH 07/10] Move several Part methods to Common

---
 crates/kas-widgets/src/edit/editor.rs | 89 ++++++++++++++-------------
 1 file changed, 47 insertions(+), 42 deletions(-)

diff --git a/crates/kas-widgets/src/edit/editor.rs b/crates/kas-widgets/src/edit/editor.rs
index e851e25fa..980d95c6d 100644
--- a/crates/kas-widgets/src/edit/editor.rs
+++ b/crates/kas-widgets/src/edit/editor.rs
@@ -573,7 +573,7 @@ impl Part {
         self.prepare_runs(common, highlighter);
         if self.prepare_wrap(common) {
             cx.resize();
-            self.set_view_offset_from_cursor(common, cx);
+            common.set_view_offset_from_cursor(self, cx);
         }
         cx.redraw();
     }
@@ -747,7 +747,7 @@ impl Part {
         let range = match event {
             Event::NavFocus(source) if source == FocusSource::Key => {
                 if !common.input_handler.is_selecting() {
-                    self.request_key_focus(common, cx, source);
+                    common.request_key_focus(cx, source);
                 }
                 return EventAction::Used;
             }
@@ -758,14 +758,14 @@ impl Part {
                 // the latter. We must set before calling self.set_primary.
                 common.has_key_focus = true;
                 if source == FocusSource::Pointer {
-                    self.set_primary(common, cx);
+                    common.set_primary(self, cx);
                 }
 
                 return EventAction::Used;
             }
             Event::KeyFocus => {
                 common.has_key_focus = true;
-                self.set_view_offset_from_cursor(common, cx);
+                common.set_view_offset_from_cursor(self, cx);
 
                 return if common.current.is_none() {
                     let hint = Default::default();
@@ -789,7 +789,7 @@ impl Part {
             Event::LostSelFocus => {
                 // NOTE: we can assume that we will receive Ime::Disabled if IME is active
                 if !common.selection.is_empty() {
-                    self.save_undo_state(common, None);
+                    common.save_undo_state(self, None);
                     common.selection.clear_selection();
                 }
                 common.input_handler.stop_selecting();
@@ -799,7 +799,7 @@ impl Part {
             Event::Command(cmd, code) => match self.cmd_action(common, cx, cmd, code) {
                 Ok(action) => {
                     if matches!(action, EventAction::Cursor) {
-                        self.set_view_offset_from_cursor(common, cx);
+                        common.set_view_offset_from_cursor(self, cx);
                     }
                     return action;
                 }
@@ -809,7 +809,7 @@ impl Part {
                 if event.state == ElementState::Pressed && !common.read_only =>
             {
                 return if let Some(text) = &event.text {
-                    self.save_undo_state(common, Some(EditOp::KeyInput));
+                    common.save_undo_state(self, Some(EditOp::KeyInput));
                     self.cancel_selection_and_ime(common, cx);
 
                     let selection = common.selection.to_range();
@@ -827,7 +827,7 @@ impl Part {
                         match self.cmd_action(common, cx, cmd, Some(event.physical_key)) {
                             Ok(action) => {
                                 if matches!(action, EventAction::Cursor) {
-                                    self.set_view_offset_from_cursor(common, cx);
+                                    common.set_view_offset_from_cursor(self, cx);
                                 }
                                 action
                             }
@@ -868,7 +868,7 @@ impl Part {
                     };
                 }
                 Ime::Preedit { text, cursor } => {
-                    self.save_undo_state(common, None);
+                    common.save_undo_state(self, None);
                     let mut edit_range = match common.current.clone() {
                         CurrentAction::ImeStart if cursor.is_some() => common.selection.to_range(),
                         CurrentAction::ImeStart => return EventAction::Used,
@@ -892,7 +892,7 @@ impl Part {
                     return EventAction::Preedit;
                 }
                 Ime::Commit { text } => {
-                    self.save_undo_state(common, Some(EditOp::Ime));
+                    common.save_undo_state(self, Some(EditOp::Ime));
                     let edit_range = match common.current.clone() {
                         CurrentAction::ImeStart => common.selection.to_range(),
                         CurrentAction::ImePreedit { edit_range } => edit_range.cast(),
@@ -912,7 +912,7 @@ impl Part {
                     before_bytes,
                     after_bytes,
                 } => {
-                    self.save_undo_state(common, None);
+                    common.save_undo_state(self, None);
                     let edit_range = match common.current.clone() {
                         CurrentAction::ImeStart => common.selection.to_range(),
                         CurrentAction::ImePreedit { edit_range } => edit_range.cast(),
@@ -957,10 +957,10 @@ impl Part {
                 let rel_pos = (press.coord - self.rect().pos).cast();
                 let mut index = self.display.text_index_nearest(rel_pos);
                 self.cancel_selection_and_ime(common, cx);
-                self.request_key_focus(common, cx, FocusSource::Pointer);
+                common.request_key_focus(cx, FocusSource::Pointer);
 
                 if let Some(content) = cx.get_primary() {
-                    self.save_undo_state(common, Some(EditOp::Clipboard));
+                    common.save_undo_state(self, Some(EditOp::Clipboard));
 
                     let range = self.trim_paste(common.wrap, &content);
                     self.replace_range(index..index, &content[range.clone()]);
@@ -981,8 +981,8 @@ impl Part {
                         self.clear_ime(common);
                         cx.cancel_ime_focus(&common.id);
                     }
-                    self.request_key_focus(common, cx, FocusSource::Pointer);
-                    self.save_undo_state(common, Some(EditOp::Cursor));
+                    common.request_key_focus(cx, FocusSource::Pointer);
+                    common.save_undo_state(self, Some(EditOp::Cursor));
                     common.current = CurrentAction::Selection;
 
                     let rel_pos = (coord - self.rect().pos).cast();
@@ -1022,9 +1022,9 @@ impl Part {
                         self.clear_ime(common);
                         cx.cancel_ime_focus(&common.id);
                     }
-                    self.save_undo_state(common, Some(EditOp::Cursor));
+                    common.save_undo_state(self, Some(EditOp::Cursor));
                     if common.current == CurrentAction::Selection {
-                        self.set_primary(common, cx);
+                        common.set_primary(self, cx);
                     } else {
                         let rel_pos = (coord - self.rect().pos).cast();
                         let index = self.display.text_index_nearest(rel_pos);
@@ -1033,7 +1033,7 @@ impl Part {
                     }
                     common.current = CurrentAction::None;
 
-                    self.request_key_focus(common, cx, FocusSource::Pointer);
+                    common.request_key_focus(cx, FocusSource::Pointer);
                     return EventAction::Used;
                 }
             },
@@ -1041,7 +1041,7 @@ impl Part {
 
         if range != common.selection {
             common.selection = range;
-            self.set_view_offset_from_cursor(common, cx);
+            common.set_view_offset_from_cursor(self, cx);
             common.edit_x_coord = None;
             cx.redraw();
         }
@@ -1186,30 +1186,33 @@ impl Part {
 
         cx.set_ime_cursor_area(&common.id, rect + Offset::conv(self.rect.pos));
     }
+}
 
+impl Common {
     /// Call before an edit to (potentially) commit current state based on last_edit
     ///
     /// Call with [`None`] to force commit of any uncommitted changes.
-    fn save_undo_state(&mut self, common: &mut Common, edit: Option<EditOp>) {
+    fn save_undo_state(&mut self, part: &mut Part, edit: Option<EditOp>) {
         if let Some(op) = edit
-            && op.try_merge(&mut common.last_edit)
+            && op.try_merge(&mut self.last_edit)
         {
             return;
         }
 
-        common.last_edit = edit;
-        common
-            .undo_stack
-            .try_push((self.as_str().to_string(), common.selection));
+        self.last_edit = edit;
+        self.undo_stack
+            .try_push((part.as_str().to_string(), self.selection));
     }
 
     /// Request key focus, if we don't have it or IME
-    fn request_key_focus(&self, common: &Common, cx: &mut EventCx, source: FocusSource) {
-        if !common.has_key_focus && !common.current.is_ime_enabled() {
-            cx.request_key_focus(common.id.clone(), source);
+    fn request_key_focus(&self, cx: &mut EventCx, source: FocusSource) {
+        if !self.has_key_focus && !self.current.is_ime_enabled() {
+            cx.request_key_focus(self.id.clone(), source);
         }
     }
+}
 
+impl Part {
     fn trim_paste(&self, wrap: bool, text: &str) -> Range<usize> {
         let mut end = text.len();
         if !wrap {
@@ -1455,7 +1458,7 @@ impl Part {
         // We can receive some commands without key focus as a result of
         // selection focus. Request focus on edit actions (like Command::Cut).
         if !matches!(action, Action::None | Action::Deselect) {
-            self.request_key_focus(common, cx, FocusSource::Synthetic);
+            common.request_key_focus(cx, FocusSource::Synthetic);
         }
 
         if !matches!(action, Action::None) {
@@ -1468,7 +1471,7 @@ impl Part {
             Action::Activate | Action::UndoRedo(_) => None,
             Action::Insert(_, edit) | Action::Delete(_, edit) => Some(edit),
         };
-        self.save_undo_state(common, edit_op);
+        common.save_undo_state(self, edit_op);
 
         let action = match action {
             Action::None => unreachable!(),
@@ -1502,7 +1505,7 @@ impl Part {
                 if !shift {
                     common.selection.clear_selection();
                 } else {
-                    self.set_primary(common, cx);
+                    common.set_primary(self, cx);
                 }
                 common.edit_x_coord = x_coord;
                 cx.redraw();
@@ -1525,12 +1528,14 @@ impl Part {
 
         Ok(action)
     }
+}
 
+impl Common {
     /// Set primary clipboard (mouse buffer) contents from selection
-    fn set_primary(&self, common: &Common, cx: &mut EventCx) {
-        if common.has_key_focus && !common.selection.is_empty() && cx.has_primary() {
-            let range = common.selection.to_range();
-            cx.set_primary(String::from(&self.as_str()[range]));
+    fn set_primary(&self, part: &Part, cx: &mut EventCx) {
+        if self.has_key_focus && !self.selection.is_empty() && cx.has_primary() {
+            let range = self.selection.to_range();
+            cx.set_primary(String::from(&part.as_str()[range]));
         }
     }
 
@@ -1539,13 +1544,13 @@ impl Part {
     /// It is assumed that the text has not changed.
     ///
     /// A redraw is assumed since the cursor moved.
-    fn set_view_offset_from_cursor(&mut self, common: &Common, cx: &mut EventCx) {
-        let cursor = common.selection.cursor;
-        if self.is_prepared()
-            && let Some(marker) = self.display.text_glyph_pos(cursor).next_back()
+    fn set_view_offset_from_cursor(&self, part: &Part, cx: &mut EventCx) {
+        let cursor = self.selection.cursor;
+        if part.is_prepared()
+            && let Some(marker) = part.display.text_glyph_pos(cursor).next_back()
         {
             let y0 = (marker.pos.1 - marker.ascent).cast_floor();
-            let pos = self.rect.pos + Offset(marker.pos.0.cast_nearest(), y0);
+            let pos = part.rect.pos + Offset(marker.pos.0.cast_nearest(), y0);
             let size = Size(0, i32::conv_ceil(marker.pos.1 - marker.descent) - y0);
             cx.set_scroll(Scroll::Rect(Rect { pos, size }));
         }
@@ -1593,8 +1598,8 @@ impl Editor {
     /// [`Self::set_string`] to commit changes to the undo history.
     #[inline]
     pub fn pre_commit(&mut self) {
-        self.part
-            .save_undo_state(&mut self.common, Some(EditOp::Synthetic));
+        self.common
+            .save_undo_state(&mut self.part, Some(EditOp::Synthetic));
     }
 
     /// Clear text contents and undo history

From c95609ed0388e4b4906aa2abbaf5c08020a1eb65 Mon Sep 17 00:00:00 2001
From: Diggory Hardy <git@dhardy.name>
Date: Fri, 1 May 2026 07:31:35 +0000
Subject: [PATCH 08/10] Move code for methods remaining in Part

---
 crates/kas-widgets/src/edit/editor.rs | 282 +++++++++++++-------------
 1 file changed, 141 insertions(+), 141 deletions(-)

diff --git a/crates/kas-widgets/src/edit/editor.rs b/crates/kas-widgets/src/edit/editor.rs
index 980d95c6d..d738b1a58 100644
--- a/crates/kas-widgets/src/edit/editor.rs
+++ b/crates/kas-widgets/src/edit/editor.rs
@@ -727,6 +727,147 @@ impl Part {
         }
     }
 
+    /// Replace a section of text
+    ///
+    /// This may be used to edit the raw text instead of replacing it.
+    /// One must call [`Text::prepare`] afterwards.
+    ///
+    /// One may simulate an unbounded range by via `start..usize::MAX`.
+    ///
+    /// Currently this is not significantly more efficient than
+    /// [`Text::set_text`]. This may change in the future (TODO).
+    #[inline]
+    fn replace_range(&mut self, range: std::ops::Range<usize>, replace_with: &str) {
+        self.text.replace_range(range, replace_with);
+        self.require_reprepare();
+    }
+
+    fn trim_paste(&self, wrap: bool, text: &str) -> Range<usize> {
+        let mut end = text.len();
+        if !wrap {
+            // We cut the content short on control characters and
+            // ignore them (preventing line-breaks and ignoring any
+            // actions such as recursive-paste).
+            for (i, c) in text.char_indices() {
+                if c < '\u{20}' || ('\u{7f}'..='\u{9f}').contains(&c) {
+                    end = i;
+                    break;
+                }
+            }
+        }
+        0..end
+    }
+
+    /// Clean up IME state
+    ///
+    /// One should also call [`EventCx::cancel_ime_focus`] unless this is
+    /// implied.
+    fn clear_ime(&mut self, common: &mut Common) {
+        if common.current.is_ime_enabled() {
+            let action = std::mem::replace(&mut common.current, CurrentAction::None);
+            if let CurrentAction::ImePreedit { edit_range } = action {
+                common.selection.set_position(edit_range.start.cast());
+                self.replace_range(edit_range.cast(), "");
+            }
+        }
+    }
+
+    fn ime_surrounding_text(&self, common: &Common) -> Option<ImeSurroundingText> {
+        const MAX_TEXT_BYTES: usize = ImeSurroundingText::MAX_TEXT_BYTES;
+
+        let sel_range = common.selection.to_range();
+        let edit_range = match common.current.clone() {
+            CurrentAction::ImePreedit { edit_range } => Some(edit_range.cast()),
+            _ => None,
+        };
+        let mut range = edit_range.clone().unwrap_or(sel_range);
+        let initial_range = range.clone();
+        let edit_len = edit_range.clone().map(|r| r.len()).unwrap_or(0);
+
+        if self.status >= Status::Wrapped {
+            if let Some((_, line_range)) = self.display.find_line(range.start) {
+                range.start = line_range.start;
+            }
+            if let Some((_, line_range)) = self.display.find_line(range.end) {
+                range.end = line_range.end;
+            }
+        }
+
+        if range.len() - edit_len > MAX_TEXT_BYTES {
+            range.end = range.end.min(initial_range.end + MAX_TEXT_BYTES / 2);
+            while !self.as_str().is_char_boundary(range.end) {
+                range.end -= 1;
+            }
+
+            if range.len() - edit_len > MAX_TEXT_BYTES {
+                range.start = range.start.max(initial_range.start - MAX_TEXT_BYTES / 2);
+                while !self.as_str().is_char_boundary(range.start) {
+                    range.start += 1;
+                }
+            }
+        }
+
+        let start = range.start;
+        let mut text = String::with_capacity(range.len() - edit_len);
+        if let Some(er) = edit_range {
+            text.push_str(&self.as_str()[range.start..er.start]);
+            text.push_str(&self.as_str()[er.end..range.end]);
+        } else {
+            text = self.as_str()[range].to_string();
+        }
+
+        let cursor = common.selection.cursor.saturating_sub(start);
+        // Terminology difference: our sel_index is called 'anchor'
+        let sel_index = common.selection.anchor.saturating_sub(start);
+        ImeSurroundingText::new(text, cursor, sel_index)
+            .inspect_err(|err| {
+                // TODO: use Display for err not Debug
+                log::warn!("Editor::ime_surrounding_text failed: {err:?}")
+            })
+            .ok()
+    }
+
+    /// Call to set IME position only while IME is active
+    fn set_ime_cursor_area(&self, common: &Common, cx: &mut EventState) {
+        if !self.is_prepared() {
+            return;
+        }
+
+        let range = match common.current.clone() {
+            CurrentAction::ImeStart => common.selection.to_range(),
+            CurrentAction::ImePreedit { edit_range } => edit_range.cast(),
+            _ => return,
+        };
+
+        let (m1, m2);
+        if range.is_empty() {
+            let mut iter = self.display.text_glyph_pos(range.start);
+            m1 = iter.next();
+            m2 = iter.next();
+        } else {
+            m1 = self.display.text_glyph_pos(range.start).next_back();
+            m2 = self.display.text_glyph_pos(range.end).next();
+        }
+
+        let rect = if let Some((c1, c2)) = m1.zip(m2) {
+            let left = c1.pos.0.min(c2.pos.0);
+            let right = c1.pos.0.max(c2.pos.0);
+            let top = (c1.pos.1 - c1.ascent).min(c2.pos.1 - c2.ascent);
+            let bottom = (c1.pos.1 - c1.descent).max(c2.pos.1 - c2.ascent);
+            let p1 = Vec2(left, top).cast_floor();
+            let p2 = Vec2(right, bottom).cast_ceil();
+            Rect::from_coords(p1, p2)
+        } else if let Some(c) = m1.or(m2) {
+            let p1 = Vec2(c.pos.0, c.pos.1 - c.ascent).cast_floor();
+            let p2 = Vec2(c.pos.0, c.pos.1 - c.descent).cast_ceil();
+            Rect::from_coords(p1, p2)
+        } else {
+            return;
+        };
+
+        cx.set_ime_cursor_area(&common.id, rect + Offset::conv(self.rect.pos));
+    }
+
     /// Handle an event
     ///
     /// If [`EventAction::requires_repreparation`] then the caller **must** call
@@ -1048,21 +1189,6 @@ impl Part {
         event_action
     }
 
-    /// Replace a section of text
-    ///
-    /// This may be used to edit the raw text instead of replacing it.
-    /// One must call [`Text::prepare`] afterwards.
-    ///
-    /// One may simulate an unbounded range by via `start..usize::MAX`.
-    ///
-    /// Currently this is not significantly more efficient than
-    /// [`Text::set_text`]. This may change in the future (TODO).
-    #[inline]
-    fn replace_range(&mut self, range: std::ops::Range<usize>, replace_with: &str) {
-        self.text.replace_range(range, replace_with);
-        self.require_reprepare();
-    }
-
     /// Cancel on-going selection and IME actions
     ///
     /// This should be called if e.g. key-input interrupts the current
@@ -1076,116 +1202,6 @@ impl Part {
             cx.cancel_ime_focus(&common.id);
         }
     }
-
-    /// Clean up IME state
-    ///
-    /// One should also call [`EventCx::cancel_ime_focus`] unless this is
-    /// implied.
-    fn clear_ime(&mut self, common: &mut Common) {
-        if common.current.is_ime_enabled() {
-            let action = std::mem::replace(&mut common.current, CurrentAction::None);
-            if let CurrentAction::ImePreedit { edit_range } = action {
-                common.selection.set_position(edit_range.start.cast());
-                self.replace_range(edit_range.cast(), "");
-            }
-        }
-    }
-
-    fn ime_surrounding_text(&self, common: &Common) -> Option<ImeSurroundingText> {
-        const MAX_TEXT_BYTES: usize = ImeSurroundingText::MAX_TEXT_BYTES;
-
-        let sel_range = common.selection.to_range();
-        let edit_range = match common.current.clone() {
-            CurrentAction::ImePreedit { edit_range } => Some(edit_range.cast()),
-            _ => None,
-        };
-        let mut range = edit_range.clone().unwrap_or(sel_range);
-        let initial_range = range.clone();
-        let edit_len = edit_range.clone().map(|r| r.len()).unwrap_or(0);
-
-        if self.status >= Status::Wrapped {
-            if let Some((_, line_range)) = self.display.find_line(range.start) {
-                range.start = line_range.start;
-            }
-            if let Some((_, line_range)) = self.display.find_line(range.end) {
-                range.end = line_range.end;
-            }
-        }
-
-        if range.len() - edit_len > MAX_TEXT_BYTES {
-            range.end = range.end.min(initial_range.end + MAX_TEXT_BYTES / 2);
-            while !self.as_str().is_char_boundary(range.end) {
-                range.end -= 1;
-            }
-
-            if range.len() - edit_len > MAX_TEXT_BYTES {
-                range.start = range.start.max(initial_range.start - MAX_TEXT_BYTES / 2);
-                while !self.as_str().is_char_boundary(range.start) {
-                    range.start += 1;
-                }
-            }
-        }
-
-        let start = range.start;
-        let mut text = String::with_capacity(range.len() - edit_len);
-        if let Some(er) = edit_range {
-            text.push_str(&self.as_str()[range.start..er.start]);
-            text.push_str(&self.as_str()[er.end..range.end]);
-        } else {
-            text = self.as_str()[range].to_string();
-        }
-
-        let cursor = common.selection.cursor.saturating_sub(start);
-        // Terminology difference: our sel_index is called 'anchor'
-        let sel_index = common.selection.anchor.saturating_sub(start);
-        ImeSurroundingText::new(text, cursor, sel_index)
-            .inspect_err(|err| {
-                // TODO: use Display for err not Debug
-                log::warn!("Editor::ime_surrounding_text failed: {err:?}")
-            })
-            .ok()
-    }
-
-    /// Call to set IME position only while IME is active
-    fn set_ime_cursor_area(&self, common: &Common, cx: &mut EventState) {
-        if !self.is_prepared() {
-            return;
-        }
-
-        let range = match common.current.clone() {
-            CurrentAction::ImeStart => common.selection.to_range(),
-            CurrentAction::ImePreedit { edit_range } => edit_range.cast(),
-            _ => return,
-        };
-
-        let (m1, m2);
-        if range.is_empty() {
-            let mut iter = self.display.text_glyph_pos(range.start);
-            m1 = iter.next();
-            m2 = iter.next();
-        } else {
-            m1 = self.display.text_glyph_pos(range.start).next_back();
-            m2 = self.display.text_glyph_pos(range.end).next();
-        }
-
-        let rect = if let Some((c1, c2)) = m1.zip(m2) {
-            let left = c1.pos.0.min(c2.pos.0);
-            let right = c1.pos.0.max(c2.pos.0);
-            let top = (c1.pos.1 - c1.ascent).min(c2.pos.1 - c2.ascent);
-            let bottom = (c1.pos.1 - c1.descent).max(c2.pos.1 - c2.ascent);
-            let p1 = Vec2(left, top).cast_floor();
-            let p2 = Vec2(right, bottom).cast_ceil();
-            Rect::from_coords(p1, p2)
-        } else if let Some(c) = m1.or(m2) {
-            let p1 = Vec2(c.pos.0, c.pos.1 - c.ascent).cast_floor();
-            let p2 = Vec2(c.pos.0, c.pos.1 - c.descent).cast_ceil();
-            Rect::from_coords(p1, p2)
-        } else {
-            return;
-        };
-
-        cx.set_ime_cursor_area(&common.id, rect + Offset::conv(self.rect.pos));
-    }
 }
 
 impl Common {
@@ -1213,22 +1229,6 @@ impl Common {
 }
 
 impl Part {
-    fn trim_paste(&self, wrap: bool, text: &str) -> Range<usize> {
-        let mut end = text.len();
-        if !wrap {
-            // We cut the content short on control characters and
-            // ignore them (preventing line-breaks and ignoring any
-            // actions such as recursive-paste).
-            for (i, c) in text.char_indices() {
-                if c < '\u{20}' || ('\u{7f}'..='\u{9f}').contains(&c) {
-                    end = i;
-                    break;
-                }
-            }
-        }
-        0..end
-    }
-
     /// Drive action of a [`Command`]
     fn cmd_action(
         &mut self,

From 9e6fc49459b3678e3e7809b8b9d478de94fad259 Mon Sep 17 00:00:00 2001
From: Diggory Hardy <git@dhardy.name>
Date: Wed, 29 Apr 2026 14:13:42 +0000
Subject: [PATCH 09/10] Add fn Part::handle_ime

---
 crates/kas-widgets/src/edit/editor.rs | 227 ++++++++++++++------------
 1 file changed, 119 insertions(+), 108 deletions(-)

diff --git a/crates/kas-widgets/src/edit/editor.rs b/crates/kas-widgets/src/edit/editor.rs
index d738b1a58..a7e79f0da 100644
--- a/crates/kas-widgets/src/edit/editor.rs
+++ b/crates/kas-widgets/src/edit/editor.rs
@@ -868,11 +868,122 @@ impl Part {
         cx.set_ime_cursor_area(&common.id, rect + Offset::conv(self.rect.pos));
     }
 
+    /// Handle IME methods on a given `Part`.
+    fn handle_ime(&mut self, common: &mut Common, cx: &mut EventCx, event: Ime) -> EventAction {
+        match event {
+            Ime::Enabled => {
+                match common.current {
+                    CurrentAction::None => {
+                        common.current = CurrentAction::ImeStart;
+                        self.set_ime_cursor_area(common, cx);
+                    }
+                    CurrentAction::ImeStart | CurrentAction::ImePreedit { .. } => {
+                        // already enabled
+                    }
+                    CurrentAction::Selection => {
+                        unreachable!()
+                    }
+                }
+                if !common.has_key_focus {
+                    EventAction::FocusGained
+                } else {
+                    EventAction::Used
+                }
+            }
+            Ime::Disabled => {
+                self.clear_ime(common);
+                if !common.has_key_focus {
+                    EventAction::FocusLost
+                } else {
+                    EventAction::Used
+                }
+            }
+            Ime::Preedit { text, cursor } => {
+                common.save_undo_state(self, None);
+                let mut edit_range = match common.current.clone() {
+                    CurrentAction::ImeStart if cursor.is_some() => common.selection.to_range(),
+                    CurrentAction::ImeStart => return EventAction::Used,
+                    CurrentAction::ImePreedit { edit_range } => edit_range.cast(),
+                    _ => return EventAction::Used,
+                };
+
+                self.replace_range(edit_range.clone(), text);
+                edit_range.end = edit_range.start + text.len();
+                if let Some((start, end)) = cursor {
+                    common.selection.anchor = edit_range.start + start;
+                    common.selection.cursor = edit_range.start + end;
+                } else {
+                    common.selection.set_position(edit_range.start + text.len());
+                }
+
+                common.current = CurrentAction::ImePreedit {
+                    edit_range: edit_range.cast(),
+                };
+                common.edit_x_coord = None;
+                EventAction::Preedit
+            }
+            Ime::Commit { text } => {
+                common.save_undo_state(self, Some(EditOp::Ime));
+                let edit_range = match common.current.clone() {
+                    CurrentAction::ImeStart => common.selection.to_range(),
+                    CurrentAction::ImePreedit { edit_range } => edit_range.cast(),
+                    _ => return EventAction::Used,
+                };
+
+                self.replace_range(edit_range.clone(), text);
+                common.selection.set_position(edit_range.start + text.len());
+
+                common.current = CurrentAction::ImePreedit {
+                    edit_range: common.selection.to_range().cast(),
+                };
+                common.edit_x_coord = None;
+                EventAction::Edit
+            }
+            Ime::DeleteSurrounding {
+                before_bytes,
+                after_bytes,
+            } => {
+                common.save_undo_state(self, None);
+                let edit_range = match common.current.clone() {
+                    CurrentAction::ImeStart => common.selection.to_range(),
+                    CurrentAction::ImePreedit { edit_range } => edit_range.cast(),
+                    _ => return EventAction::Used,
+                };
+
+                if before_bytes > 0 {
+                    let end = edit_range.start;
+                    let start = end - before_bytes;
+                    if self.as_str().is_char_boundary(start) {
+                        self.replace_range(start..end, "");
+                        common.selection.delete_range(start..end);
+                    } else {
+                        log::warn!("buggy IME tried to delete range not at char boundary");
+                    }
+                }
+
+                if after_bytes > 0 {
+                    let start = edit_range.end;
+                    let end = start + after_bytes;
+                    if self.as_str().is_char_boundary(end) {
+                        self.replace_range(start..end, "");
+                    } else {
+                        log::warn!("buggy IME tried to delete range not at char boundary");
+                    }
+                }
+
+                if let Some(text) = self.ime_surrounding_text(common) {
+                    cx.update_ime_surrounding_text(&common.id, text);
+                }
+
+                EventAction::Used
+            }
+        }
+    }
+
     /// Handle an event
     ///
     /// If [`EventAction::requires_repreparation`] then the caller **must** call
     /// re-prepare the text by calling [`Self::prepare_and_scroll`].
-    #[inline]
     pub fn handle_event(
         &mut self,
         common: &mut Common,
@@ -979,115 +1090,15 @@ impl Part {
                     }
                 };
             }
-            Event::Ime(ime) => match ime {
-                Ime::Enabled => {
-                    match common.current {
-                        CurrentAction::None => {
-                            common.current = CurrentAction::ImeStart;
-                            self.set_ime_cursor_area(common, cx);
-                        }
-                        CurrentAction::ImeStart | CurrentAction::ImePreedit { .. } => {
-                            // already enabled
-                        }
-                        CurrentAction::Selection => {
-                            // Do not interrupt selection
-                            cx.cancel_ime_focus(&common.id);
-                        }
-                    }
-                    return if !common.has_key_focus {
-                        EventAction::FocusGained
-                    } else {
-                        EventAction::Used
-                    };
-                }
-                Ime::Disabled => {
-                    self.clear_ime(common);
-                    return if !common.has_key_focus {
-                        EventAction::FocusLost
-                    } else {
-                        EventAction::Used
-                    };
+            Event::Ime(ime) => {
+                if matches!(common.current, CurrentAction::Selection) {
+                    // Selection takes priority over IME
+                    cx.cancel_ime_focus(&common.id);
+                    return EventAction::Unused;
                 }
-                Ime::Preedit { text, cursor } => {
-                    common.save_undo_state(self, None);
-                    let mut edit_range = match common.current.clone() {
-                        CurrentAction::ImeStart if cursor.is_some() => common.selection.to_range(),
-                        CurrentAction::ImeStart => return EventAction::Used,
-                        CurrentAction::ImePreedit { edit_range } => edit_range.cast(),
-                        _ => return EventAction::Used,
-                    };
-
-                    self.replace_range(edit_range.clone(), text);
-                    edit_range.end = edit_range.start + text.len();
-                    if let Some((start, end)) = cursor {
-                        common.selection.anchor = edit_range.start + start;
-                        common.selection.cursor = edit_range.start + end;
-                    } else {
-                        common.selection.set_position(edit_range.start + text.len());
-                    }
-
-                    common.current = CurrentAction::ImePreedit {
-                        edit_range: edit_range.cast(),
-                    };
-                    common.edit_x_coord = None;
-                    return EventAction::Preedit;
-                }
-                Ime::Commit { text } => {
-                    common.save_undo_state(self, Some(EditOp::Ime));
-                    let edit_range = match common.current.clone() {
-                        CurrentAction::ImeStart => common.selection.to_range(),
-                        CurrentAction::ImePreedit { edit_range } => edit_range.cast(),
-                        _ => return EventAction::Used,
-                    };
 
-                    self.replace_range(edit_range.clone(), text);
-                    common.selection.set_position(edit_range.start + text.len());
-
-                    common.current = CurrentAction::ImePreedit {
-                        edit_range: common.selection.to_range().cast(),
-                    };
-                    common.edit_x_coord = None;
-                    return EventAction::Edit;
-                }
-                Ime::DeleteSurrounding {
-                    before_bytes,
-                    after_bytes,
-                } => {
-                    common.save_undo_state(self, None);
-                    let edit_range = match common.current.clone() {
-                        CurrentAction::ImeStart => common.selection.to_range(),
-                        CurrentAction::ImePreedit { edit_range } => edit_range.cast(),
-                        _ => return EventAction::Used,
-                    };
-
-                    if before_bytes > 0 {
-                        let end = edit_range.start;
-                        let start = end - before_bytes;
-                        if self.as_str().is_char_boundary(start) {
-                            self.replace_range(start..end, "");
-                            common.selection.delete_range(start..end);
-                        } else {
-                            log::warn!("buggy IME tried to delete range not at char boundary");
-                        }
-                    }
-
-                    if after_bytes > 0 {
-                        let start = edit_range.end;
-                        let end = start + after_bytes;
-                        if self.as_str().is_char_boundary(end) {
-                            self.replace_range(start..end, "");
-                        } else {
-                            log::warn!("buggy IME tried to delete range not at char boundary");
-                        }
-                    }
-
-                    if let Some(text) = self.ime_surrounding_text(common) {
-                        cx.update_ime_surrounding_text(&common.id, text);
-                    }
-
-                    return EventAction::Used;
-                }
-            },
+                return self.handle_ime(common, cx, ime);
+            }
             Event::PressStart(press) if press.is_tertiary() => {
                 return match press.grab_click(common.id.clone()).complete(cx) {
                     Unused => EventAction::Unused,

From a871adb2b96ca7c1885a832a69009e76a5c49b2c Mon Sep 17 00:00:00 2001
From: Diggory Hardy <git@dhardy.name>
Date: Wed, 29 Apr 2026 13:59:42 +0000
Subject: [PATCH 10/10] Move more Part methods to Common

---
 crates/kas-widgets/src/edit/editor.rs | 290 ++++++++++++--------------
 1 file changed, 139 insertions(+), 151 deletions(-)

diff --git a/crates/kas-widgets/src/edit/editor.rs b/crates/kas-widgets/src/edit/editor.rs
index a7e79f0da..96fdfe678 100644
--- a/crates/kas-widgets/src/edit/editor.rs
+++ b/crates/kas-widgets/src/edit/editor.rs
@@ -353,7 +353,7 @@ impl<H: Highlighter> Component<H> {
     /// Handle an event
     #[inline]
     pub fn handle_event(&mut self, cx: &mut EventCx, event: Event) -> EventAction {
-        let action = self.0.part.handle_event(&mut self.0.common, cx, event);
+        let action = self.0.common.handle_event(&mut self.0.part, cx, event);
         if action.requires_repreparation() {
             self.0
                 .part
@@ -979,18 +979,15 @@ impl Part {
             }
         }
     }
+}
 
+impl Common {
     /// Handle an event
     ///
     /// If [`EventAction::requires_repreparation`] then the caller **must** call
-    /// re-prepare the text by calling [`Self::prepare_and_scroll`].
-    pub fn handle_event(
-        &mut self,
-        common: &mut Common,
-        cx: &mut EventCx,
-        event: Event,
-    ) -> EventAction {
-        if !self.is_prepared() {
+    /// re-prepare the text by calling [`Part::prepare_and_scroll`].
+    pub fn handle_event(&mut self, part: &mut Part, cx: &mut EventCx, event: Event) -> EventAction {
+        if !part.is_prepared() {
             debug_assert!(false);
             return EventAction::Unused;
         }
@@ -998,8 +995,8 @@ impl Part {
         let mut event_action = EventAction::Used;
         let range = match event {
             Event::NavFocus(source) if source == FocusSource::Key => {
-                if !common.input_handler.is_selecting() {
-                    common.request_key_focus(cx, source);
+                if !self.input_handler.is_selecting() {
+                    self.request_key_focus(cx, source);
                 }
                 return EventAction::Used;
             }
@@ -1008,31 +1005,31 @@ impl Part {
             Event::SelFocus(source) => {
                 // NOTE: sel focus implies key focus since we only request
                 // the latter. We must set before calling self.set_primary.
-                common.has_key_focus = true;
+                self.has_key_focus = true;
                 if source == FocusSource::Pointer {
-                    common.set_primary(self, cx);
+                    self.set_primary(part, cx);
                 }
 
                 return EventAction::Used;
             }
             Event::KeyFocus => {
-                common.has_key_focus = true;
-                common.set_view_offset_from_cursor(self, cx);
+                self.has_key_focus = true;
+                self.set_view_offset_from_cursor(part, cx);
 
-                return if common.current.is_none() {
+                return if self.current.is_none() {
                     let hint = Default::default();
                     let purpose = ImePurpose::Normal;
-                    let surrounding_text = self.ime_surrounding_text(common);
-                    cx.replace_ime_focus(common.id.clone(), hint, purpose, surrounding_text);
+                    let surrounding_text = part.ime_surrounding_text(self);
+                    cx.replace_ime_focus(self.id.clone(), hint, purpose, surrounding_text);
                     EventAction::FocusGained
                 } else {
                     EventAction::Used
                 };
             }
             Event::LostKeyFocus => {
-                common.has_key_focus = false;
+                self.has_key_focus = false;
                 cx.redraw();
-                return if !common.current.is_ime_enabled() {
+                return if !self.current.is_ime_enabled() {
                     EventAction::FocusLost
                 } else {
                     EventAction::Used
@@ -1040,34 +1037,32 @@ impl Part {
             }
             Event::LostSelFocus => {
                 // NOTE: we can assume that we will receive Ime::Disabled if IME is active
-                if !common.selection.is_empty() {
-                    common.save_undo_state(self, None);
-                    common.selection.clear_selection();
+                if !self.selection.is_empty() {
+                    self.save_undo_state(part, None);
+                    self.selection.clear_selection();
                 }
-                common.input_handler.stop_selecting();
+                self.input_handler.stop_selecting();
                 cx.redraw();
                 return EventAction::Used;
             }
-            Event::Command(cmd, code) => match self.cmd_action(common, cx, cmd, code) {
+            Event::Command(cmd, code) => match self.cmd_action(part, cx, cmd, code) {
                 Ok(action) => {
                     if matches!(action, EventAction::Cursor) {
-                        common.set_view_offset_from_cursor(self, cx);
+                        self.set_view_offset_from_cursor(part, cx);
                     }
                     return action;
                 }
                 Err(NotReady) => return EventAction::Used,
             },
-            Event::Key(event, false)
-                if event.state == ElementState::Pressed && !common.read_only =>
-            {
+            Event::Key(event, false) if event.state == ElementState::Pressed && !self.read_only => {
                 return if let Some(text) = &event.text {
-                    common.save_undo_state(self, Some(EditOp::KeyInput));
-                    self.cancel_selection_and_ime(common, cx);
+                    self.save_undo_state(part, Some(EditOp::KeyInput));
+                    self.cancel_selection_and_ime(part, cx);
 
-                    let selection = common.selection.to_range();
-                    self.replace_range(selection.clone(), text);
-                    common.selection.set_position(selection.start + text.len());
-                    common.edit_x_coord = None;
+                    let selection = self.selection.to_range();
+                    part.replace_range(selection.clone(), text);
+                    self.selection.set_position(selection.start + text.len());
+                    self.edit_x_coord = None;
 
                     EventAction::Edit
                 } else {
@@ -1076,10 +1071,10 @@ impl Part {
                         .shortcuts()
                         .try_match_event(cx.modifiers(), event);
                     if let Some(cmd) = opt_cmd {
-                        match self.cmd_action(common, cx, cmd, Some(event.physical_key)) {
+                        match self.cmd_action(part, cx, cmd, Some(event.physical_key)) {
                             Ok(action) => {
                                 if matches!(action, EventAction::Cursor) {
-                                    common.set_view_offset_from_cursor(self, cx);
+                                    self.set_view_offset_from_cursor(part, cx);
                                 }
                                 action
                             }
@@ -1091,37 +1086,37 @@ impl Part {
                 };
             }
             Event::Ime(ime) => {
-                if matches!(common.current, CurrentAction::Selection) {
+                if matches!(self.current, CurrentAction::Selection) {
                     // Selection takes priority over IME
-                    cx.cancel_ime_focus(&common.id);
+                    cx.cancel_ime_focus(&self.id);
                     return EventAction::Unused;
                 }
 
-                return self.handle_ime(common, cx, ime);
+                return part.handle_ime(self, cx, ime);
             }
             Event::PressStart(press) if press.is_tertiary() => {
-                return match press.grab_click(common.id.clone()).complete(cx) {
+                return match press.grab_click(self.id.clone()).complete(cx) {
                     Unused => EventAction::Unused,
                     Used => EventAction::Used,
                 };
             }
             Event::PressEnd { press, .. } if press.is_tertiary() => {
-                let rel_pos = (press.coord - self.rect().pos).cast();
-                let mut index = self.display.text_index_nearest(rel_pos);
-                self.cancel_selection_and_ime(common, cx);
-                common.request_key_focus(cx, FocusSource::Pointer);
+                let rel_pos = (press.coord - part.rect().pos).cast();
+                let mut index = part.display.text_index_nearest(rel_pos);
+                self.cancel_selection_and_ime(part, cx);
+                self.request_key_focus(cx, FocusSource::Pointer);
 
                 if let Some(content) = cx.get_primary() {
-                    common.save_undo_state(self, Some(EditOp::Clipboard));
+                    self.save_undo_state(part, Some(EditOp::Clipboard));
 
-                    let range = self.trim_paste(common.wrap, &content);
-                    self.replace_range(index..index, &content[range.clone()]);
+                    let range = part.trim_paste(self.wrap, &content);
+                    part.replace_range(index..index, &content[range.clone()]);
                     index += range.len();
                     event_action = EventAction::Edit;
                 }
                 index.into()
             }
-            event => match common.input_handler.handle(cx, common.id.clone(), event) {
+            event => match self.input_handler.handle(cx, self.id.clone(), event) {
                 TextInputAction::Used => return EventAction::Used,
                 TextInputAction::Unused => return EventAction::Unused,
                 TextInputAction::PressStart {
@@ -1129,72 +1124,72 @@ impl Part {
                     clear,
                     repeats,
                 } => {
-                    if common.current.is_ime_enabled() {
-                        self.clear_ime(common);
-                        cx.cancel_ime_focus(&common.id);
+                    if self.current.is_ime_enabled() {
+                        part.clear_ime(self);
+                        cx.cancel_ime_focus(&self.id);
                     }
-                    common.request_key_focus(cx, FocusSource::Pointer);
-                    common.save_undo_state(self, Some(EditOp::Cursor));
-                    common.current = CurrentAction::Selection;
+                    self.request_key_focus(cx, FocusSource::Pointer);
+                    self.save_undo_state(part, Some(EditOp::Cursor));
+                    self.current = CurrentAction::Selection;
 
-                    let rel_pos = (coord - self.rect().pos).cast();
-                    let cursor = self.display.text_index_nearest(rel_pos);
-                    let anchor = if clear { cursor } else { common.selection.anchor };
+                    let rel_pos = (coord - part.rect().pos).cast();
+                    let cursor = part.display.text_index_nearest(rel_pos);
+                    let anchor = if clear { cursor } else { self.selection.anchor };
 
                     let range = CursorRange::from(anchor..cursor);
                     if repeats > 1 {
                         TextInput::expand_range(
-                            self.text.as_str(),
+                            part.text.as_str(),
                             range,
                             (repeats >= 3)
-                                .then_some(&|index| self.display.find_line(index).map(|r| r.1)),
+                                .then_some(&|index| part.display.find_line(index).map(|r| r.1)),
                         )
                     } else {
                         range
                     }
                 }
                 TextInputAction::PressMove { coord, repeats } => {
-                    if common.current != CurrentAction::Selection {
+                    if self.current != CurrentAction::Selection {
                         return EventAction::Used;
                     }
 
-                    let rel_pos = (coord - self.rect().pos).cast();
-                    let index = self.display.text_index_nearest(rel_pos);
+                    let rel_pos = (coord - part.rect().pos).cast();
+                    let index = part.display.text_index_nearest(rel_pos);
 
                     TextInput::adjust_range(
-                        self.text.as_str(),
-                        common.selection,
+                        part.text.as_str(),
+                        self.selection,
                         index,
                         repeats,
-                        Some(&|index| self.display.find_line(index).map(|r| r.1)),
+                        Some(&|index| part.display.find_line(index).map(|r| r.1)),
                     )
                 }
                 TextInputAction::PressEnd { coord } => {
-                    if common.current.is_ime_enabled() {
-                        self.clear_ime(common);
-                        cx.cancel_ime_focus(&common.id);
+                    if self.current.is_ime_enabled() {
+                        part.clear_ime(self);
+                        cx.cancel_ime_focus(&self.id);
                     }
-                    common.save_undo_state(self, Some(EditOp::Cursor));
-                    if common.current == CurrentAction::Selection {
-                        common.set_primary(self, cx);
+                    self.save_undo_state(part, Some(EditOp::Cursor));
+                    if self.current == CurrentAction::Selection {
+                        self.set_primary(part, cx);
                     } else {
-                        let rel_pos = (coord - self.rect().pos).cast();
-                        let index = self.display.text_index_nearest(rel_pos);
-                        common.selection.cursor = index;
-                        common.selection.clear_selection();
+                        let rel_pos = (coord - part.rect().pos).cast();
+                        let index = part.display.text_index_nearest(rel_pos);
+                        self.selection.cursor = index;
+                        self.selection.clear_selection();
                     }
-                    common.current = CurrentAction::None;
+                    self.current = CurrentAction::None;
 
-                    common.request_key_focus(cx, FocusSource::Pointer);
+                    self.request_key_focus(cx, FocusSource::Pointer);
                     return EventAction::Used;
                 }
             },
         };
 
-        if range != common.selection {
-            common.selection = range;
-            common.set_view_offset_from_cursor(self, cx);
-            common.edit_x_coord = None;
+        if range != self.selection {
+            self.selection = range;
+            self.set_view_offset_from_cursor(part, cx);
+            self.edit_x_coord = None;
             cx.redraw();
         }
         event_action
@@ -1204,18 +1199,16 @@ impl Part {
     ///
     /// This should be called if e.g. key-input interrupts the current
     /// action.
-    fn cancel_selection_and_ime(&mut self, common: &mut Common, cx: &mut EventState) {
-        if common.current == CurrentAction::Selection {
-            common.input_handler.stop_selecting();
-            common.current = CurrentAction::None;
-        } else if common.current.is_ime_enabled() {
-            self.clear_ime(common);
-            cx.cancel_ime_focus(&common.id);
+    fn cancel_selection_and_ime(&mut self, part: &mut Part, cx: &mut EventState) {
+        if self.current == CurrentAction::Selection {
+            self.input_handler.stop_selecting();
+            self.current = CurrentAction::None;
+        } else if self.current.is_ime_enabled() {
+            part.clear_ime(self);
+            cx.cancel_ime_focus(&self.id);
         }
     }
-}
 
-impl Common {
     /// Call before an edit to (potentially) commit current state based on last_edit
     ///
     /// Call with [`None`] to force commit of any uncommitted changes.
@@ -1237,30 +1230,27 @@ impl Common {
             cx.request_key_focus(self.id.clone(), source);
         }
     }
-}
-
-impl Part {
     /// Drive action of a [`Command`]
     fn cmd_action(
         &mut self,
-        common: &mut Common,
+        part: &mut Part,
         cx: &mut EventCx,
         mut cmd: Command,
         code: Option<PhysicalKey>,
     ) -> Result<EventAction, NotReady> {
-        debug_assert!(self.is_prepared());
+        debug_assert!(part.is_prepared());
 
-        let editable = !common.read_only;
+        let editable = !self.read_only;
         let mut shift = cx.modifiers().shift_key();
         let mut buf = [0u8; 4];
-        let cursor = common.selection.cursor;
-        let len = self.as_str().len();
-        let multi_line = common.wrap;
-        let selection = common.selection.to_range();
+        let cursor = self.selection.cursor;
+        let len = part.as_str().len();
+        let multi_line = self.wrap;
+        let selection = self.selection.to_range();
         let have_sel = selection.end > selection.start;
         let string;
 
-        if self.text_is_rtl() {
+        if part.text_is_rtl() {
             match cmd {
                 Command::Left => cmd = Command::Right,
                 Command::Right => cmd = Command::Left,
@@ -1294,7 +1284,7 @@ impl Part {
                 Action::Move(selection.start, None)
             }
             Command::Left if cursor > 0 => GraphemeCursor::new(cursor, len, true)
-                .prev_boundary(self.as_str(), 0)
+                .prev_boundary(part.as_str(), 0)
                 .unwrap()
                 .map(|index| Action::Move(index, None))
                 .unwrap_or(Action::None),
@@ -1302,14 +1292,14 @@ impl Part {
                 Action::Move(selection.end, None)
             }
             Command::Right if cursor < len => GraphemeCursor::new(cursor, len, true)
-                .next_boundary(self.as_str(), 0)
+                .next_boundary(part.as_str(), 0)
                 .unwrap()
                 .map(|index| Action::Move(index, None))
                 .unwrap_or(Action::None),
             Command::WordLeft if cursor > 0 => {
-                let mut iter = self.as_str()[0..cursor].split_word_bound_indices();
+                let mut iter = part.as_str()[0..cursor].split_word_bound_indices();
                 let mut p = iter.next_back().map(|(index, _)| index).unwrap_or(0);
-                while self.as_str()[p..]
+                while part.as_str()[p..]
                     .chars()
                     .next()
                     .map(|c| c.is_whitespace())
@@ -1324,9 +1314,9 @@ impl Part {
                 Action::Move(p, None)
             }
             Command::WordRight if cursor < len => {
-                let mut iter = self.as_str()[cursor..].split_word_bound_indices().skip(1);
+                let mut iter = part.as_str()[cursor..].split_word_bound_indices().skip(1);
                 let mut p = iter.next().map(|(index, _)| cursor + index).unwrap_or(len);
-                while self.as_str()[p..]
+                while part.as_str()[p..]
                     .chars()
                     .next()
                     .map(|c| c.is_whitespace())
@@ -1343,16 +1333,16 @@ impl Part {
             // Avoid use of unused navigation keys (e.g. by ScrollComponent):
             Command::Left | Command::Right | Command::WordLeft | Command::WordRight => Action::None,
             Command::Up | Command::Down if multi_line => {
-                let x = match common.edit_x_coord {
+                let x = match self.edit_x_coord {
                     Some(x) => x,
-                    None => self
+                    None => part
                         .display
                         .text_glyph_pos(cursor)
                         .next_back()
                         .map(|r| r.pos.0)
                         .unwrap_or(0.0),
                 };
-                let mut line = self.display.find_line(cursor).map(|r| r.0).unwrap_or(0);
+                let mut line = part.display.find_line(cursor).map(|r| r.0).unwrap_or(0);
                 // We can tolerate invalid line numbers here!
                 line = match cmd {
                     Command::Up => line.wrapping_sub(1),
@@ -1364,13 +1354,13 @@ impl Part {
                     0..=HALF => len,
                     _ => 0,
                 };
-                self.display
+                part.display
                     .line_index_nearest(line, x)
                     .map(|index| Action::Move(index, Some(x)))
                     .unwrap_or(Action::Move(nearest_end, None))
             }
             Command::Home if cursor > 0 => {
-                let index = self
+                let index = part
                     .display
                     .find_line(cursor)
                     .map(|r| r.1.start)
@@ -1378,7 +1368,7 @@ impl Part {
                 Action::Move(index, None)
             }
             Command::End if cursor < len => {
-                let index = self
+                let index = part
                     .display
                     .find_line(cursor)
                     .map(|r| r.1.end)
@@ -1390,18 +1380,18 @@ impl Part {
             // Avoid use of unused navigation keys (e.g. by ScrollComponent):
             Command::Home | Command::End | Command::DocHome | Command::DocEnd => Action::None,
             Command::PageUp | Command::PageDown if multi_line => {
-                let mut v = self
+                let mut v = part
                     .display
                     .text_glyph_pos(cursor)
                     .next_back()
                     .map(|r| r.pos.into())
                     .unwrap_or(Vec2::ZERO);
-                if let Some(x) = common.edit_x_coord {
+                if let Some(x) = self.edit_x_coord {
                     v.0 = x;
                 }
                 // TODO: page height should be an input?
-                let mut line_height = common.dpem;
-                if let Some(line) = self.display.lines().next() {
+                let mut line_height = self.dpem;
+                if let Some(line) = part.display.lines().next() {
                     line_height = line.bottom() - line.top();
                 }
                 let mut h_dist = line_height * 10.0;
@@ -1409,23 +1399,23 @@ impl Part {
                     h_dist *= -1.0;
                 }
                 v.1 += h_dist;
-                Action::Move(self.display.text_index_nearest(v.into()), Some(v.0))
+                Action::Move(part.display.text_index_nearest(v.into()), Some(v.0))
             }
             Command::Delete | Command::DelBack if editable && have_sel => {
                 Action::Delete(selection.clone(), EditOp::Delete)
             }
             Command::Delete if editable => GraphemeCursor::new(cursor, len, true)
-                .next_boundary(self.as_str(), 0)
+                .next_boundary(part.as_str(), 0)
                 .unwrap()
                 .map(|next| Action::Delete(cursor..next, EditOp::Delete))
                 .unwrap_or(Action::None),
             Command::DelBack if editable => GraphemeCursor::new(cursor, len, true)
-                .prev_boundary(self.as_str(), 0)
+                .prev_boundary(part.as_str(), 0)
                 .unwrap()
                 .map(|prev| Action::Delete(prev..cursor, EditOp::Delete))
                 .unwrap_or(Action::None),
             Command::DelWord if editable => {
-                let next = self.as_str()[cursor..]
+                let next = part.as_str()[cursor..]
                     .split_word_bound_indices()
                     .nth(1)
                     .map(|(index, _)| cursor + index)
@@ -1433,7 +1423,7 @@ impl Part {
                 Action::Delete(cursor..next, EditOp::Delete)
             }
             Command::DelWordBack if editable => {
-                let prev = self.as_str()[0..cursor]
+                let prev = part.as_str()[0..cursor]
                     .split_word_bound_indices()
                     .next_back()
                     .map(|(index, _)| index)
@@ -1441,21 +1431,21 @@ impl Part {
                 Action::Delete(prev..cursor, EditOp::Delete)
             }
             Command::SelectAll => {
-                common.selection.anchor = 0;
+                self.selection.anchor = 0;
                 shift = true; // hack
                 Action::Move(len, None)
             }
             Command::Cut if editable && have_sel => {
-                cx.set_clipboard((self.as_str()[selection.clone()]).into());
+                cx.set_clipboard((part.as_str()[selection.clone()]).into());
                 Action::Delete(selection.clone(), EditOp::Clipboard)
             }
             Command::Copy if have_sel => {
-                cx.set_clipboard((self.as_str()[selection.clone()]).into());
+                cx.set_clipboard((part.as_str()[selection.clone()]).into());
                 Action::None
             }
             Command::Paste if editable => {
                 if let Some(content) = cx.get_clipboard() {
-                    let range = self.trim_paste(common.wrap, &content);
+                    let range = part.trim_paste(self.wrap, &content);
                     string = content;
                     Action::Insert(&string[range], EditOp::Clipboard)
                 } else {
@@ -1469,11 +1459,11 @@ impl Part {
         // We can receive some commands without key focus as a result of
         // selection focus. Request focus on edit actions (like Command::Cut).
         if !matches!(action, Action::None | Action::Deselect) {
-            common.request_key_focus(cx, FocusSource::Synthetic);
+            self.request_key_focus(cx, FocusSource::Synthetic);
         }
 
         if !matches!(action, Action::None) {
-            self.cancel_selection_and_ime(common, cx);
+            self.cancel_selection_and_ime(part, cx);
         }
 
         let edit_op = match action {
@@ -1482,12 +1472,12 @@ impl Part {
             Action::Activate | Action::UndoRedo(_) => None,
             Action::Insert(_, edit) | Action::Delete(_, edit) => Some(edit),
         };
-        common.save_undo_state(self, edit_op);
+        self.save_undo_state(part, edit_op);
 
         let action = match action {
             Action::None => unreachable!(),
             Action::Deselect => {
-                common.selection.clear_selection();
+                self.selection.clear_selection();
                 cx.redraw();
                 EventAction::Cursor
             }
@@ -1500,36 +1490,36 @@ impl Part {
                 } else {
                     index..index
                 };
-                self.replace_range(range, s);
-                common.selection.set_position(index + s.len());
-                common.edit_x_coord = None;
+                part.replace_range(range, s);
+                self.selection.set_position(index + s.len());
+                self.edit_x_coord = None;
                 EventAction::Edit
             }
             Action::Delete(sel, _) => {
-                self.replace_range(sel.clone(), "");
-                common.selection.set_position(sel.start);
-                common.edit_x_coord = None;
+                part.replace_range(sel.clone(), "");
+                self.selection.set_position(sel.start);
+                self.edit_x_coord = None;
                 EventAction::Edit
             }
             Action::Move(index, x_coord) => {
-                common.selection.cursor = index;
+                self.selection.cursor = index;
                 if !shift {
-                    common.selection.clear_selection();
+                    self.selection.clear_selection();
                 } else {
-                    common.set_primary(self, cx);
+                    self.set_primary(part, cx);
                 }
-                common.edit_x_coord = x_coord;
+                self.edit_x_coord = x_coord;
                 cx.redraw();
                 EventAction::Cursor
             }
             Action::UndoRedo(redo) => {
-                if let Some((text, cursor)) = common.undo_stack.undo_or_redo(redo) {
-                    if self.text.as_str() != text {
-                        self.text = text.clone();
-                        self.status = Status::New;
-                        common.edit_x_coord = None;
+                if let Some((text, cursor)) = self.undo_stack.undo_or_redo(redo) {
+                    if part.text.as_str() != text {
+                        part.text = text.clone();
+                        part.status = Status::New;
+                        self.edit_x_coord = None;
                     }
-                    common.selection = *cursor;
+                    self.selection = *cursor;
                     EventAction::Edit
                 } else {
                     EventAction::Used
@@ -1539,9 +1529,7 @@ impl Part {
 
         Ok(action)
     }
-}
 
-impl Common {
     /// Set primary clipboard (mouse buffer) contents from selection
     fn set_primary(&self, part: &Part, cx: &mut EventCx) {
         if self.has_key_focus && !self.selection.is_empty() && cx.has_primary() {
@@ -1646,7 +1634,7 @@ impl Editor {
             return; // no change
         }
 
-        self.part.cancel_selection_and_ime(&mut self.common, cx);
+        self.common.cancel_selection_and_ime(&mut self.part, cx);
 
         self.part.text = text;
         self.part.require_reprepare();
@@ -1663,7 +1651,7 @@ impl Editor {
     /// guard.
     #[inline]
     pub fn replace_selected_text(&mut self, cx: &mut EventState, text: &str) {
-        self.part.cancel_selection_and_ime(&mut self.common, cx);
+        self.common.cancel_selection_and_ime(&mut self.part, cx);
 
         let selection = self.common.selection.to_range();
         self.part.replace_range(selection.clone(), text);