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+---
+allowed-tools: Bash(container *), Bash(cargo *), Read, Grep, Glob
+---
+
+# Run Tests in Linux Container (Apple `container` CLI)
+
+Run RustPython tests inside a Linux container using Apple's `container` CLI.
+**NEVER use Docker, Podman, or any other container runtime.** Only use the `container` command.
+
+## Arguments
+- `$ARGUMENTS`: Test command to run (e.g., `test_io`, `test_codecs -v`, `test_io -v -m "test_errors"`)
+
+## Prerequisites
+
+The `container` CLI is installed via `brew install container`.
+The dev image `rustpython-dev` is already built.
+
+## Steps
+
+1. **Check if the container is already running**
+   ```shell
+   container list 2>/dev/null | grep rustpython-test
+   ```
+
+2. **Start the container if not running**
+   ```shell
+   container run -d --name rustpython-test -m 8G -c 4 \
+       --mount type=bind,source=/Users/al03219714/Projects/RustPython3,target=/workspace \
+       -w /workspace rustpython-dev sleep infinity
+   ```
+
+3. **Run the test inside the container**
+   ```shell
+   container exec rustpython-test sh -c "cargo run --release -- -m test $ARGUMENTS"
+   ```
+
+4. **Report results**
+   - Show test summary (pass/fail counts, expected failures, unexpected successes)
+   - Highlight any new failures compared to macOS results if available
+   - Do NOT stop or remove the container after testing (keep it for reuse)
+
+## Notes
+- The workspace is bind-mounted, so local code changes are immediately available
+- Use `container exec rustpython-test sh -c "..."` for any command inside the container
+- To rebuild after code changes, run: `container exec rustpython-test sh -c "cargo build --release"`
+- To stop the container when done: `container rm -f rustpython-test`