Purpose
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Regression tests for :mod:`oct.mcp.sandbox` — ``SandboxExecutor`` and
environment sanitisation.
Responsibilities
----------------
- Verify environment sanitisation strips sensitive variables.
- Verify timeout enforcement and output-size limits.
- Verify T-04 (command chaining) and shell=False enforcement.
- Verify exit-code forwarding from subprocess.
Diagnostics
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Domain: MCP-TESTS
Levels:
L2 — test lifecycle
L3 — assertion details
L4 — deep tracing
Contracts
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- Tests use mock subprocess; no real commands are executed.