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Simulator: launch and terminate natively (simctl), not through XCTest - #138
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Root cause of the 2026-10-10 hangs, from the driver's own log: the app was not installed on the device, and XCUIApplication.launch() does not fail fast — it records the failure, then waits for accessibility (120 s), takes a spindump and waits for idle: 4 minutes inside one request. The driver serves requests one at a time, so its health checks hung too and the host replaced it, then resent the launch. Lifecycle now runs on the host through CoreSimulator: an installed check (simctl get_app_container, ~0.3 s), terminate, launch (instant, returns the pid or the reason). The driver only attaches to the running app for UI work — the live suite (Settings: launch, find, tap, navigate) passes that way. A transport failure is resent after a driver relaunch only when the request never reached the driver or is safe to repeat (a timed-out tap must not tap twice). Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
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Root cause (from the hung driver session's own log, 2026-10-10): the app wasn't installed on the device, and
XCUIApplication.launch()doesn't fail fast — it records the failure, then waits for accessibility (120 s), takes a spindump, then waits for idle: ~4 minutes inside one request. The driver serves requests serially, so its health checks hung, the host replaced the driver (3× in 10 min) and resent the launch.Fix:
SimLifecycle(host, CoreSimulator viasimctl): installed check (get_app_container, ~0.3 s), terminate, launch (instant; pid or reason).SimClient.launch/terminateuse it;not_installed/launch_failederrors name the next step. The driver only attaches to the running app for UI work.Verified: unit tests (lifecycle: not installed fails at once with no HTTP; terminate-first order; simctl failure message; resend policy). Live:
SAK_LIVE_TESTS=1 SAK_SIM_TESTS=1SimLiveTests 4/4 pass on iOS 26.1 with native launch (driver reads/finds/taps/navigates an app it didn't launch). Manual: installed probe 0.2–0.3 s; launch of Quakely instant. Fullswift testgreen.🤖 Generated with Claude Code