Files
amethyst/tools/ime-test/README.md
T
Vitor PamplonaandClaude Opus 4.8 8232cd50a3 test(embed): add IME/selection test harness + document how to run it
tools/ime-test/index.html is a single-page input+textarea harness with an
on-page log timestamping focus/selection/input/composition events, paint
latency, long-tasks, and main-thread blocks — the instrumentation used to pin
the erase / caret-jump / first-letter-freeze bugs and what we'll use to profile
the magnifier. README documents serving it (python http.server on 8765,
10.0.2.2 for emulator / adb reverse for USB) and opening it as an embedded tab
via the in-app browser address bar. Plan gets a matching "How to test" section.

Dev tool only — nothing under tools/ ships, so the [ImeDiag] strings stay out of src/.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-25 21:25:55 -04:00

2.5 KiB

IME / text-selection test harness

A single-file web page (index.html) for exercising and profiling the embedded WebView IME + text-selection relay (see amethyst/plans/2026-06-25-embed-text-selection-native-parity.md). It has a plain <input> and a <textarea> plus an on-page green log that records, with millisecond timestamps:

  • focus/blur, selectionchange, keydown/beforeinput/input, composition events, and the resulting value/selection — to catch erase, caret-jump, and focus-transfer regressions;
  • paint latency (requestAnimationFrame after each DOM change) — the metric that exposed the first-letter freeze;
  • long-task + main-thread-block detectors and a focus/selection heartbeat — to catch anything stalling the WebView main thread or spontaneously moving focus/selection.

The log lines are tagged [ImeDiag] and also go to console.log, so they show up in adb logcat (the :napplet process owns the WebView console). Nothing here ships in the app — it's a dev tool, which is why the [ImeDiag] strings live only under tools/.

Run it

  1. Serve this directory over HTTP from your dev machine:

    cd tools/ime-test && python3 -m http.server 8765
    
  2. Reach it from the device/emulator:

    • Emulator: the page is at http://10.0.2.2:8765 (10.0.2.2 is the emulator's alias for the host loopback).
    • Physical device (USB): adb reverse tcp:8765 tcp:8765, then the page is at http://localhost:8765.
  3. Open that URL as an embedded tab (this is the path that uses the relay — not a full-screen activity):

    • Open the in-app browser (BrowserScreen) and type the URL into its address bar. The embedded browser handles http/https, so it loads into the :napplet SurfaceControlViewHost surface.

    To compare against native behavior, open the same URL in a full-screen activity (where the WebView renders in-window with the native keyboard) — that is also how you reproduce the full-screen round-trip highlight bug (open full-screen, back, then selection highlight is dead across all embeds).

Reading the log

  • INPUT … val=… sel=… right after a keystroke with the right value = no erase.
  • PAINT-LATENCY Nms spiking to ~1000ms = the first-letter freeze (should stay low now that the surface no longer resizes on IME show).
  • MAINTHREAD BLOCKED / LONGTASK = something is stalling the WebView thread.
  • HEARTBEAT lines changing while idle = spontaneous focus/selection drift.