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+# sporel-lib-core.input-test
+
+P.3.3 test-lib — validates `lib-core.input` v0.4.0 API contracts (BIND_MAP,
+`was_action_released`, engine mouse-surface) via the `engine.test.*` assertion surface.
+17 assertions total.
+
+- Lib-ID: `lib-core.input-test`
+- Version: `0.1.0`
+- Kind: `test-lib` (headless; M.run_tests(ctx) invoked by engine test-runner)
+- Spec: `meta/docs/superpowers/specs/2026-05-12-p3-3-mouse-input-design.md`
+
+## Run
+
+```bash
+Sporel.exe --libs-dir=<libs-path> --test-libs=lib-core.input-test
+```
+
+Output is TAP version 13 on stdout; exit-code = failure-count (0 = all pass).
+
+## Coverage Statements (2026-05-16 Fault-Injection Audit)
+
+Verified via deliberate-mutation in fixture-mirror; mutations reverted after observation.
+
+### Caught Mutations
+
+| # | Mutation | Caught by |
+|---|---|---|
+| M1 | `function M.was_action_released` renamed to `M._was_action_released_disabled` (API-break) | Runtime error "attempt to call a nil value (field 'was_action_released')" — test aborts after assertion 14 |
+| M2 | `if not entries then return false end` changed to `return nil` (wrong return type for unknown action) | Assertion "was_action_released for unknown action returns false" (ok 16) — `not ok`, got nil |
+
+### Uncaught Mutations (Gaps)
+
+| # | Mutation | Why uncaught | Severity |
+|---|---|---|---|
+| M3 | Dispatch-swap in `was_action_released` for-loop: key-kind entries call `was_mouse_released`, mouse-kind call `was_released` | Headless mode: all input queries return false regardless of correct vs swapped dispatch — no real events to differentiate the paths | Med |
+
+**Resolution per Gap:**
+- Gap M3: Headless-unreachable — requires real key/mouse events to distinguish `was_released` from `was_mouse_released`. Future-Slice B: integration test with simulated input events. No cheap headless fill possible.
+
+### Tested Production-Lib Surface
+
+`lib-core.input` v0.4.0 — Tests cover behavior of: `input.bind` (mouse-string acceptance, mixed key+mouse, unknown-name rejection, atomicity), `input.action_count`, `input.is_action_down`, `input.was_action_pressed`, `input.was_action_released` (bound action headless=false; unknown action=false). Engine surface assertions: `MOUSE_LEFT/RIGHT/MIDDLE` constants, `is_mouse_down`, `was_mouse_pressed`, `was_released`, `was_mouse_released` function presence.