# lib-core.camera-test

Test-lib for `lib-core.camera` (Tests-as-Libs per ADR-0037).

**Version:** 0.1.0  
**Lib-ID:** lib-core.camera-test  
**Requires:** lib-core.camera v>=0.3.0, lib-core.input v>=0.4.0  
**Tags:** test, camera

## Topology

<!-- topology:start (auto-generated; do not edit) -->
```mermaid
graph LR
  this["lib-core.camera-test"]
  lib_core_camera["lib-core.camera"]
  this --> lib_core_camera
  lib_core_input["lib-core.input"]
  this --> lib_core_input
  engine["engine.*"]
  this --> engine
```
<!-- topology:end -->

## Coverage Statement

Per Fault-Injection-Audit-Convention (2026-05-16):

| Section | Assertion-Count | Coverage |
|---|---|---|
| State setters/getters | 3 | `set_target`/`target`, `set_zoom`/`zoom`, `set_pan_speed`/`pan_speed` |
| Bounds-Clamping | 3 | `set_bounds` clamping, `clear_bounds` -> unclamped, immediate-clamp on bounds-shrink |
| pan_enabled state | 6 | Per-source disable (keys/edge/drag), `bind_pan_keys` auto-enable, toggle false/true |
| pan_invert state | 2 | `set_pan_invert(false)`, `set_pan_invert(true)` |
| Engine-Surface existence | 2 | `engine.input.get_mouse_delta`, `engine.window.size` function presence |
| **TOTAL** | **16** | |

### Tested-Surface
- `camera.set_target` / `camera.target` (value + bounds-clamping)
- `camera.set_zoom` / `camera.zoom`
- `camera.set_pan_speed` / `camera.pan_speed`
- `camera.set_bounds`, `camera.clear_bounds`
- `camera.bind_pan_keys` (auto-enable side-effect)
- `camera.set_pan_enabled` / `camera.pan_enabled` (toggle false/true)
- `camera.set_pan_invert` / `camera.pan_invert`
- Engine surface: `engine.input.get_mouse_delta`, `engine.window.size`

### Fault-Injection Audit (2026-05-16)

Verified via deliberate-mutation in fixture-mirror; mutations reverted after observation.

| # | Mutation | Caught by |
|---|---|---|
| M1 | `set_target`: x/y assignments swapped | Assertions 1 (`set_target -> target`) + 4 (`set_target clamped to bounds`) fail |
| M2 | `clear_bounds` made no-op | Assertion 5 (`clear_bounds -> unclamped`) fails |
| M3 | `bind_pan_keys` auto-enable removed | Assertion 10 (`bind_pan_keys auto-enables`) fails |

All 3 mutations caught — no gaps detected.

### Structurally Untestable
- `camera.begin` / `camera.finish` — render-stack side-effects only observable inside a render hook; headless test-runner has no render context.
- `camera.update(dt)` interaction with per-frame mouse-input — requires live `engine.input` polling state.
- `camera.screen_to_world` — requires live window-size from `engine.window.size`, headless returns 0 (deferred).

### Deferred
- `enable_pan_edge`, `bind_pan_drag` runtime behavior (covered indirectly via `pan_enabled` toggles).
- `set_edge_threshold` / `edge_threshold` getter/setter pair.

## Running

Via `--test-libs=lib-core.camera-test` (Smoke P0-S-batch Stage):

```bash
Sporel.exe --libs-dir=<libs-path> --test-libs=lib-core.camera-test
```

Output is TAP version 13 on stdout; exit-code = failure-count (0 = all pass).

## References

- ADR-0037 (Tests-as-Libs Convention)
- ADR-0038 (API-Doc-Convention)
- Production-Lib: `~/Projects/Sporel/sporel-libs/lib-core/camera/README.md`
- Spec: `meta/docs/superpowers/specs/2026-05-13-p3-5-camera-free-pan-design.md`