# Tests

Pure-Python unit + property tests for the algorithm layer. These tests do
**not** import SGLang and do **not** need a GPU — they validate the routing
algorithm (Algorithm 1/2/3 in `docs/KVC_ROUTER_ALGORITHM.md`) and its
theorems against the pure functions extracted from `policies.py`.

## Run

```bash
uv sync --group test
uv run pytest
```

Or, without uv:

```bash
pip install pytest
PYTHONPATH=src pytest tests
```

## Scope

- `test_policy_scoring.py` — Algorithm 1 lex-score properties (overlap
  dominates sticky, load-floor gating, tie-breakers).
- `test_no_starvation.py` — Theorem 1: bounded retries before some D either
  accepts or the least-rejected D is forced through the degenerate path.

Future:
- block-level eviction `MockRadixCache` tests (see
  `docs/BLOCK_LEVEL_EVICTION_DESIGN_ZH.md` §5).
- D→P sync `staleness_budget` property tests (see
  `docs/D_TO_P_SYNC_CONTRACT_ZH.md` §1).

## Why no integration tests here

Anything that needs SGLang, mooncake, or a real model is an integration
test and must run on hardware. Those tests live as `scripts/sweep_*.sh`
under the evaluation protocol in `docs/EVALUATION_PROTOCOL_ZH.md`.