fix(simulator): Make simulator platform inference deterministic#472
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An iOS app that also supports visionOS could build for the wrong platform: when the selected simulator was unavailable (e.g. its runtime was removed by an Xcode upgrade), inference fell back to guessing from SUPPORTED_PLATFORMS, which prefers xrsimulator over iphonesimulator. - Persist simulatorPlatform during setup, derived from the selected simulator's runtime, so tools short-circuit on a cached authoritative value instead of guessing - Remove the build-settings and default-iOS fallbacks from inferPlatform; throw a clear error when no source resolves - Hydrate the CLI session store from project config so the cached platform is visible to one-shot CLI invocations - Filter unavailable simulators out of the setup picker - Invalidate the cached platform when Xcode sync changes the selector - Keep name -> id re-materialization in the background refresh (simulatorName stays the canonical, machine-portable selector for SCM-shared configs) and skip it when nothing resolves - Remove the now-dead detectPlatformFromScheme Co-Authored-By: Claude <noreply@anthropic.com>
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Codify two rules in AGENTS.md and CLAUDE.md: - Never run the snapshot or smoke test suites without explicit user permission; they are expensive (~7 min, real xcodebuild/simctl processes) while the unit suite, typecheck, lint, and build remain free to run - Structured errors (domain results with didError) are for domain errors only; system errors with the MCP server or CLI itself must surface as runtime tool errors Co-Authored-By: Claude <noreply@anthropic.com>
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- Clear the cached simulatorPlatform when the background refresh remaps the simulator id but the platform recompute fails, so a new id is never paired with the previous device's platform - Report simulatorPlatform changes in the setup summary Co-Authored-By: Claude <noreply@anthropic.com>
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Simulator tools could build for the wrong platform. With an iPhone simulator selected via
setup,simulator buildproducedplatform=visionOS Simulatorfor an iOS app that also supports visionOS, failing with "Unable to find a device matching the provided destination specifier".Root cause
When the selected simulator is unavailable (e.g. its runtime was removed by an Xcode upgrade, leaving a stale device record), platform inference found nothing in
simctl list devices availableand fell through to guessing from the scheme'sSUPPORTED_PLATFORMS— which checkedxrsimulatorbeforeiphonesimulator. For any multi-platform app the result was a coin toss, rigged toward visionOS.Changes
simulatorPlatform, derived from the selected simulator's runtime. Inference short-circuits on this cached, device-derived value — the session-defaults field existed but nothing ever wrote it.inferPlatform. Guessing a destination fromSUPPORTED_PLATFORMSis inherently non-deterministic for multi-platform apps; if no authoritative source resolves, tools now fail fast with a clear error pointing atsetup.build_run_simshows the real platform name instead of downgrading to a generic "Simulator" when inference came from the cache.detectPlatformFromSchemeremoved — it carried the visionOS-over-iOS ordering bug and had no remaining callers.The background defaults refresh keeps its name → id re-materialization:
simulatorNameremains the canonical, machine-portable selector for SCM-shared configs, and the refresh updates the machine-local UDID from it. This contract, and the deliberate asymmetry that one-shot CLI runs stay deterministic for CI (fail fast on a stale/foreign UDID rather than silently re-resolving), is now codified in code comments and schema descriptions.Notes for review
inferPlatformnow throws when it cannot resolve —build_run_simconverts that into a structured error via its existing prepare catch, whilebuild_sim/test_simsurface it as a runtime tool error.Co-Authored-By: Claude noreply@anthropic.com