fix(tui): correct IME cursor placement

.changeset/fix-ime-cursor-placement.md

@@ -0,0 +1,5 @@
+---
+"@moonshot-ai/kimi-code": patch
+---
+
+Fix IME candidate placement and cursor rendering in the terminal editor.

apps/kimi-code/src/tui/components/editor/custom-editor.ts

@@ -4,6 +4,7 @@
 
 import {
   Editor,
+  CURSOR_MARKER,
   isKeyRelease,
   matchesKey,
   Key,
@@ -23,6 +24,8 @@ const ANSI_SGR = /\u001B\[[0-9;]*m/g;
 const PASTE_MARKER_RE = /\[paste #(\d+)(?: (?:\+\d+ lines|\d+ chars))?\]/g;
 const BRACKET_PASTE_START = '\u001B[200~';
 const BRACKET_PASTE_END = '\u001B[201~';
+const FAKE_CURSOR_START = '\u001B[7m';
+const FAKE_CURSOR_END = '\u001B[0m';
 
 // Kitty keyboard protocol CSI-u sequence: ESC [ keycode ; modifier[:eventType] u.
 // We intentionally match only the simple two-field form — enough to rewrite
@@ -239,9 +242,10 @@ export class CustomEditor extends Editor {
     // overwrite it (e.g. plan-mode / slash-context highlight via
     // `editor.borderColor = chalk.hex(primary)`), so we route corners and
     // side bars through the same hook to stay in sync.
-    return wrapWithSideBorders(lines, (s) => this.borderColor(s), {
+    const wrapped = wrapWithSideBorders(lines, (s) => this.borderColor(s), {
       connectedAbove: this.connectedAbove && !this.borderHighlighted,
     });
+    return wrapped.map(removeFakeCursorAtHardwareMarker);
   }
 
   override handleInput(data: string): void {
@@ -362,6 +366,25 @@ export class CustomEditor extends Editor {
   }
 }
 
+export function removeFakeCursorAtHardwareMarker(line: string): string {
+  const markerStart = line.indexOf(CURSOR_MARKER);
+  if (markerStart < 0) return line;
+
+  const fakeCursorStart = markerStart + CURSOR_MARKER.length;
+  if (!line.startsWith(FAKE_CURSOR_START, fakeCursorStart)) return line;
+
+  const fakeCursorEnd = line.indexOf(
+    FAKE_CURSOR_END,
+    fakeCursorStart + FAKE_CURSOR_START.length,
+  );
+  if (fakeCursorEnd < 0) return line;
+
+  const cursorTextStart = fakeCursorStart + FAKE_CURSOR_START.length;
+  const cursorText = line.slice(cursorTextStart, fakeCursorEnd);
+  const afterFakeCursor = fakeCursorEnd + FAKE_CURSOR_END.length;
+  return line.slice(0, fakeCursorStart) + cursorText + line.slice(afterFakeCursor);
+}
+
 /**
  * Return a copy of `line` with the first `/token` coloured using `hex`.
  * For `/goal next manage`, also colour the command-path tokens.

apps/kimi-code/src/tui/tui-state.ts

@@ -58,7 +58,7 @@ export function createTUIState(options: KimiTUIOptions): TUIState {
   const theme = currentTheme;
 
   const terminal = new ProcessTerminal();
-  const ui = new TUI(terminal);
+  const ui = new TUI(terminal, true);
 
   const transcriptContainer = new GutterContainer(CHROME_GUTTER, CHROME_GUTTER);
   const activityContainer = new GutterContainer(CHROME_GUTTER, CHROME_GUTTER);

apps/kimi-code/test/tui/components/editor/custom-editor.test.ts

@@ -4,9 +4,13 @@ import type {
   AutocompleteSuggestions,
   TUI,
 } from '@earendil-works/pi-tui';
+import { CURSOR_MARKER } from '@earendil-works/pi-tui';
 import { describe, expect, it, vi } from 'vitest';
 
-import { CustomEditor } from '#/tui/components/editor/custom-editor';
+import {
+  CustomEditor,
+  removeFakeCursorAtHardwareMarker,
+} from '#/tui/components/editor/custom-editor';
 
 function makeEditor(): CustomEditor {
   const tui = {
@@ -132,6 +136,31 @@ describe('CustomEditor Kitty key release handling', () => {
   });
 });
 
+describe('removeFakeCursorAtHardwareMarker', () => {
+  it('removes the rendered fake cursor and keeps the hardware cursor marker in place', () => {
+    const line = `before${CURSOR_MARKER}\u001B[7m \u001B[0mafter`;
+
+    expect(removeFakeCursorAtHardwareMarker(line)).toBe(`before${CURSOR_MARKER} after`);
+  });
+
+  it('renders a focused editor with hardware cursor positioning but no fake cursor block', () => {
+    const editor = makeEditor();
+    editor.focused = true;
+    editor.setText('test');
+
+    const output = editor.render(40).join('\n');
+
+    expect(output).toContain(CURSOR_MARKER);
+    expect(output).not.toContain('\u001B[7m');
+  });
+
+  it('leaves unrelated marker-like lines untouched', () => {
+    const line = `before${CURSOR_MARKER}after`;
+
+    expect(removeFakeCursorAtHardwareMarker(line)).toBe(line);
+  });
+});
+
 describe('CustomEditor paste marker expansion', () => {
   const PASTE_START = '\x1b[200~';
   const PASTE_END = '\x1b[201~';
@@ -199,7 +228,7 @@ describe('CustomEditor paste marker expansion', () => {
 
     expect(editor.getText()).toMatch(/\[paste #1/);
 
-    editor.handleInput('\x16');
+    editor.handleInput(process.platform === 'win32' ? '\x1b[118;3u' : '\x16');
 
     expect(editor.getText()).not.toContain('[paste #');
     expect(editor.getText()).toContain(longText);

apps/kimi-code/test/tui/create-tui-state.test.ts

@@ -47,6 +47,7 @@ describe('createTUIState', () => {
 
     // UI objects are created.
     expect(state.ui).toBeDefined();
+    expect(state.ui.getShowHardwareCursor()).toBe(true);
     expect(state.terminal).toBeDefined();
     expect(state.transcriptContainer).toBeDefined();
     expect(state.activityContainer).toBeDefined();