fix: reliable IME switch on macOS 26 Tahoe (postEvent HID source + timing)#118
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Root cause (researched against macism, the reference CJK input switcher):
macOS 26 Tahoe tightened input-event timing. cmd-ime's postEvent() used a
nil CGEventSource and posted key-up immediately after key-down, which Tahoe
now drops — the Eisu/Kana switch silently fails in normal apps (regression
vs. older macOS).
Fix postEvent() to match macism's proven approach:
- real HID event source (CGEventSource(stateID: .hidSystemState)) not nil
- space key-up ~50ms after key-down, dispatched async so the event-tap
callback (main run loop) is never blocked
Also revert the Eisu/Kana switch to a single mechanism (posting the key,
which drives the IME's internal Hiragana/direct mode without stealing focus)
and remove the v2.4.7-2.4.9 TIS special-casing: bare TISSelectInputSource
only moves the menu-bar indicator unless the caller forces activation, and
the focus-stealing window workaround macism uses for its CLI is unacceptable
for a background switcher.
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Root cause (researched, not guessed)
Confirmed on-device: macOS 26.5.1 (Tahoe). Reference:
macism, the battle-tested CJK input-source switcher, documents that macOS 26 tightened input-event timing (older macOS needed ~1ms, Tahoe needs much longer).cmd-ime's
postEvent()— which posts the Eisu(102)/Kana(104) key to switch the frontmost app's IME — used two pre-Tahoe patterns that Tahoe now drops:nilCGEventSource (macism uses a realCGEventSource(stateID: .hidSystemState)).Result: on Tahoe the synthesized key is dropped and the switch silently fails in normal apps — the regression the user hit.
Why not TIS:
TISSelectInputSourcealone only moves the menu-bar indicator unless the caller forces activation (the "menu shows あ but types direct" bug — also documented by macism). macism forces it with a focus-stealing temporary window, which is fine for a one-shot CLI but unacceptable for a background switcher that must not yank focus from the app you're typing in. So the correct primitive for cmd-ime is posting the key, done right.Fix
postEvent(): real HID event source + key-up dispatched ~50ms after key-down (async, so the event-tap callback on the main run loop is never blocked).InputSourceSwitcher,isTISSwitchApp, palette-avoidance) — that whole detour was the wrong primitive for a live switcher and caused the palette-window and half-switch regressions.Tests
KeyEventTests: Kana/Eisu remap output passes through on keyDown/keyUp (the key that drives the IME).InputSourceDumpTests: skippable on-device diagnostic (CMDIME_DUMP_INPUT_SOURCES=1) that enumerates installed IMEs' TIS structure — how the Google single-mode-source fact was established.swift buildclean · 32 tests (1 skipped, 0 failures) · swiftlint 0 serious.Needs on-device confirmation (IME switching can't be verified headless): after auto-update, press the switch key in a normal app (メモ/TextEdit) and confirm it actually types Hiragana.
Version 2.4.10.