--- name: limrun-ios-simulator description: "Drive an app running on a Limrun cloud iOS simulator: launch, tap, type, read the accessibility element tree, screenshot, record video, connect the app to local services, play a video file as the camera, and run timed action chains. Use after a build (from any builder) when the user wants to see, test, or interact with their app on a simulator, or says 'show me a screenshot', 'tap', 'run the UI test', 'record a video', 'connect localhost', 'mock the camera', or 'launch on simulator'. To build the app first, use limrun-xcode-bazel (Bazel workspaces) or limrun-xcode (xcodebuild projects)." user-invocable: true effort: high --- # Limrun iOS Simulator Interact with an app running on a Limrun cloud iOS simulator, from any environment (Linux, Windows, macOS, VM, container). This skill is build-agnostic: it assumes the app was already built and installed by a build skill (`limrun-xcode-bazel` for Bazel, `limrun-xcode` for xcodebuild). Keep build concerns in those skills; this one is about driving the running simulator. Never use local Xcode, local simulators, or local macOS tools. ## Auth and CLI Install if needed: `npm install --global lim`. Auth is `lim login` or `LIM_API_KEY` (it may be set outside the project, so don't ask for it just because it's missing from `.env` or the shell). The CLI is the source of truth: the commands in this skill are verified, but if a flag errors or you need one not shown here, check `lim ios --help` instead of guessing. ## Installing an app bundle You can either use Limrun remote Bazel or Xcode services to build the app bundle and have it installed to the simulator automatically or you can sync a pre-built local `.ipa` file or `.app` folder to the simulator. The main requirement is that it must be built for simulator. ### Build and install A build skill usually attaches the simulator for you (`lim xcode rbe --ios`, or `lim xcode build .` then attach). Check what's already there: ```bash lim xcode get # is a simulator attached to the current build target? lim ios list # all running iOS instances ``` If none is attached, create one. It installs the last build immediately, so you don't need to rebuild: ```bash lim ios create --attach ``` If the create (or `lim xcode rbe --ios`) output includes a signed stream URL, share it with the user as a Markdown link, like `[Live simulator]()`. If you have a browser the user can see, open the URL there and tell them. Otherwise pass `--no-open` to `create`: it skips opening the URL locally and still prints it for sharing. `lim xcode get` prints a Limrun console URL instead. It opens the same live view but requires a console login, so prefer the signed stream URL for sharing. If the console URL is all you have, share it and mention it needs login. ### Install app from local Create a new simulator: ```bash lim ios create ``` Share the signed stream URL with the user as a Markdown link, like `[Live simulator]()`. If you have a browser the user can see, open the URL there and tell them. You can then run the following command to upload a bundle from local: ```bash lim ios sync ``` You can run the same command every time you need to install a new version of the bundle. It will patch with the difference and reload it in the simulator. ## Targeting the right instance Most `lim ios` commands default to the last created instance and resolve the "current" one from the **git repo / worktree** of your cwd. So even when a simulator is attached and `lim xcode get` shows it, a `lim ios` command can still report `No instance ID provided and no recent ios instance found`, because your cwd isn't the git worktree where the instance was created (or isn't a git repo at all). This bites most often right after `lim xcode rbe --ios` in a fresh project. The reliable recipe when that happens: ```bash lim xcode get # shows the attached simulator's ID lim ios element-tree --id # pass --id to EVERY lim ios command ``` `lim xcode get` is the dependable source for the attached simulator's ID (`lim ios list` also works). Once you have it, pass `--id ` to all `lim ios` calls for the rest of the session (screenshot, tap, type, element-tree, record). Alternatively, `git init` the project so the workspace resolves on its own. When controlling multiple instances, always pass `--id`. ## Reaching services on the local machine Destination tunnels let an iPhone simulator app keep calling exact localhost or literal-IP TCP destinations while the CLI connects those destinations from the machine running `lim`: ```bash lim ios tunnel \ --id \ --route localhost:3000 \ --route localhost:8081 \ --detach ``` Use the app's normal URLs, such as `http://localhost:3000`. Declaring `localhost:3000` also captures loopback forms such as `127.0.0.1:3000` and `[::1]:3000`, plus `[::ffff:127.0.0.1]:3000`. This release supports TCP and up to ten exact routes. Port 53, hostnames other than `localhost`, CIDRs, and UDP are not supported. One instance accepts one active destination tunnel, and its route set is immutable. To add or remove a destination, stop the tunnel and start it again with the complete route list: ```bash lim ios tunnel status --id --json lim ios tunnel stop --id ``` If the simulator attempts a route while its local service is stopped, the tunnel remains active and reports `connection_refused`; restart the service without recreating the simulator or tunnel. ## Launching the app The build skills reinstall and relaunch the app after every successful build, so you usually don't need to launch it yourself. When the app is closed (a fresh attach to an old build, or after a terminate), launch it by bundle ID: ```bash lim ios launch-app # foregrounds it if already running lim ios launch-app --mode RelaunchIfRunning # restart for a clean state lim ios terminate-app # stop it, e.g. to reset app state ``` If you don't know the bundle ID, run `lim ios list-apps`. The `lim ios launch-app` will stream the logs from the app in realtime for you to debug. If you'd like to launch and forget, you can use `--detach` flag. ## Testing changes When simulator interaction is part of the task, test new or changed functionality with the interaction commands after each build. Focus on what changed, plus a quick smoke test of core flows. Start by reading the element tree to see what's on screen before acting: ```bash lim ios element-tree ``` ## Interacting with the app Prefer tapping by accessibility id, then by label, then coordinates as a last resort: ```bash lim ios tap-element --ax-unique-id startButton lim ios tap-element --ax-label "Save" lim ios tap 201 450 ``` `tap-element` taps with a real synthesized touch. Elements the accessibility tree can see are scrolled into view automatically. A selector that matches nothing in the tree fails in about a second; iOS creates list rows lazily, so a below-the-fold row often isn't in the tree at all. For those, pass `--scroll-search`: the CLI pages the screen (a few pages down, then up) retrying the tap until the row materializes, which can take ~10s. Pass `--activate ax` to use an accessibility press instead of a touch (no scrolling, works on elements without a usable frame). **Toolbar / nav-bar items usually can't be tapped by id.** SwiftUI collapses toolbar children into a single nav-bar group, and those items report `AXUniqueId: null` even when you set `.accessibilityIdentifier(...)` (regular content `Button`s do expose it). So `tap-element --ax-unique-id` finds nothing for a nav-bar button. Set an `.accessibilityLabel` / `.accessibilityIdentifier` anyway for documentation, but to actually tap it, read its `AXFrame` from the element tree and tap the center by coordinate: ```bash lim ios element-tree --id | grep -i -A6 -B2 moon # find the item's AXFrame lim ios tap --id # tap the frame's center ``` For text input, focus a field first (tap it), then type: ```bash lim ios type "hello world" # real key events; errors if no field is focused lim ios type "hi" --no-require-focus # skip the focus check: for fields focused by coordinate taps when the accessibility focus scan is unreliable lim ios press-key backspace lim ios press-key @ # shifted symbols work directly ``` `type` presses real keys, so text delegates fire and the field's own keyboard behavior applies (a default text field autocapitalizes the first letter, for example). To set a value verbatim with no keyboard behavior, use `set-text`: ```bash lim ios set-text "P@ssw0rd!" --focused # into the focused field lim ios set-text "hello" --ax-unique-id emailField # by selector ``` For scrolling and drags: ```bash lim ios scroll down --amount 300 # from the screen center lim ios scroll down --amount 300 --coordinate 200,400 # from a specific point lim ios swipe --from 200,600 --to 200,200 # explicit drag; --duration 800 for a slower, precise one ``` After every interaction, re-run `element-tree` to confirm the UI transitioned. No sleep is needed between a tap and `element-tree`; the tap blocks until done. ```bash lim ios element-tree ``` Chain multiple actions with precise timing via `perform`: ```bash lim ios perform --action type=tap,x=100,y=200 --action "type=typeText,text=Hello World" lim ios perform --action type=wait,durationMs=1000 --action type=pressKey,key=enter lim ios perform --file ./actions.yaml ``` Run `lim ios perform --help` for the full action grammar. ## Screenshots and video Screenshot takes a **positional path** (not `-o`): ```bash lim ios screenshot screenshot.png lim ios screenshot screenshot.png --id ``` Use the element tree for functional assertions (element existence, labels, state changes) and screenshots only for visual properties. For anything involving motion (animations, gameplay, streaming UI), prefer video: ```bash lim ios record start # non-blocking lim ios record stop -o /tmp/recording.mp4 ``` For UI changes, include a demo video in the pull request so the user can see it. ## App container files List an app's data container before pulling a file so you use the exact path the app created. Keep the same `--bundle-id` and `--container-type` flags for list, pull, push, and delete: ```bash lim ios ls Documents --bundle-id com.example.app --container-type data lim ios pull-file Documents/recording.mov ./recording.mov \ --bundle-id com.example.app --container-type data lim ios push-file ./fixture.json Documents/fixture.json \ --bundle-id com.example.app --container-type data lim ios delete-file Documents/fixture.json \ --bundle-id com.example.app --container-type data ``` `lim ios ls` defaults to the staging-folder root. With `--bundle-id`, it defaults to the app bundle (`--container-type app`); use `data` for the app's writable `Documents`, `Library`, and `tmp` directories. Paths in `ls` output are relative to the selected root and can be copied directly into the other file commands. ## Simulate the camera with a video For camera-driven flows (QR-code scanning, document capture, video calls), play a local video file as the simulator's camera. The app sees the frames through its normal capture pipeline: ```bash lim ios camera play ./fixtures/qr-scan.mp4 # loops by default lim ios camera play ./fixtures/intro.mp4 --no-loop # play once, freeze on last frame lim ios camera clear # restore the default camera ``` Any AVFoundation-decodable file works (H.264/HEVC in `.mp4`/`.mov`). Use `--no-loop` when the app must observe the end of the clip exactly once (the feed freezes on the last frame rather than stalling). ## Preview URL for humans Upload the `.ipa` file directly or targz archive of the `.app` folder to Limrun Asset Storage and return a preview URL for the user to open it and test the app manually in the browser. Here is how to upload it: ```bash export ASSET_NAME=myapp.tar.gz # can be any name lim asset push ${ASSET_NAME} echo "https://console.limrun.com/preview?asset=${ASSET_NAME}&platform=ios" ``` Once the command finishes, you can give the following URL to the user to click to see a simulator where this bundle is pre-installed. ``` https://console.limrun.com/preview?asset=${ASSET_NAME}&platform=ios ``` ## Cleanup When the work is completed, you can delete the iOS simulator. ```bash lim ios delete ``` ## Gotchas - **Instance resolution can miss in a non-git dir.** See "Targeting the right instance" above; pass `--id` when in doubt. - **`element-tree` can be large.** Pipe through `grep` / `jq` to extract what you need rather than dumping the whole tree into context. - **`type` / `perform typeText` may not drive SwiftUI (or React Native) state.** Automated text injection sets the field's value through accessibility, which does **not** always fire a SwiftUI `@Binding` / `onChange` the way a real keystroke does. Symptom: the text appears in the field (and in `element-tree`), but reactive UI tied to it doesn't update (a send button stays disabled, a character counter doesn't move) and submit handlers see empty state. A real keyboard on the live stream works. When automating, drive submit through a tappable control (a button, a suggestion chip) rather than relying on text bound to reactive state, or have the app expose a test affordance. - **Toolbar / nav-bar items aren't tappable by id.** See "Interacting with the app" above: read the `AXFrame` from `element-tree` and tap by coordinate. - **Bundle ID discovery.** If you don't know the bundle ID, run `lim ios list-apps` after a successful install. - **Build errors are the build skill's job.** If the app isn't installing, the failure is upstream; go back to `limrun-xcode-bazel` / `limrun-xcode`.