fix(combat): sunder damages weapon not HP

tests/test_maneuvers.py

@@ -0,0 +1,93 @@
+"""Tests for combat maneuvers, focused on the sunder result.
+
+A successful sunder damages the defender's WEAPON, never its HP. Repeated
+sunders can destroy the weapon, after which the defender can no longer use
+it (effectively disarmed). See the plan task-12.
+"""
+
+from __future__ import annotations
+
+from pf1e_simulator.combat import CombatantState, CombatEngine
+from pf1e_simulator.grid import Grid
+from pf1e_simulator.map import MapSpec, TerrainType
+from pf1e_simulator.models import (
+    AbilityScores,
+    ACProfile,
+    AttackSpec,
+    Combatant,
+    DamageComponent,
+    Saves,
+)
+from pf1e_simulator.rng import ScriptedRng
+
+
+def make_combatant(
+    cid: str, *, attack_bonus: int = 2, weapon_name: str = "sword"
+) -> Combatant:
+    attack = AttackSpec(
+        id=f"{cid}-w",
+        name=weapon_name,
+        kind="melee",
+        attack_bonus=attack_bonus,
+        damage=[DamageComponent(formula="1d4", types=["slashing"])],
+    )
+    return Combatant(
+        id=cid,
+        name=cid,
+        level=1,
+        size="Medium",
+        abilities=AbilityScores(
+            str_score=10, dex_score=10, con_score=10,
+            int_score=10, wis_score=10, cha_score=10,
+        ),
+        hp_max=6,
+        ac=ACProfile(total=13, touch=13, flat_footed=13),
+        bab=attack_bonus,
+        initiative_mod=0,
+        speed_land_ft=30,
+        saves=Saves(fort=0, ref=0, will=0),
+        attacks=[attack],
+    )
+
+
+def make_state(combatant: Combatant, side: str, pos: tuple[int, int]) -> CombatantState:
+    return CombatantState(combatant=combatant, side=side, pos=pos, hp=combatant.hp_max)
+
+
+def make_grid() -> Grid:
+    legend = {".": TerrainType(type="floor", move_cost=1)}
+    spec = MapSpec(name="test", terrain=tuple(["." * 8] * 8), legend=legend)
+    return Grid.from_spec(spec)
+
+
+def make_engine(
+    queue: list[int], states: list[CombatantState]
+) -> CombatEngine:
+    return CombatEngine(ScriptedRng(queue), make_grid(), states)
+
+
+def test_sunder_damages_weapon_not_hp() -> None:
+    a_spec = make_combatant("a", attack_bonus=2)
+    b_spec = make_combatant("b")
+    a = make_state(a_spec, "players", (1, 1))
+    b = make_state(b_spec, "monsters", (1, 2))
+    hp_before = b.hp
+    engine = make_engine([12], [a, b])
+    engine._execute_maneuver(a, b, "sunder")
+    assert b.hp == hp_before
+    assert b.weapon_damage["b-w"] == 2
+    assert "b-w" not in b.weapon_broken
+
+
+def test_sunder_destroys_weapon_and_disarms() -> None:
+    a_spec = make_combatant("a", attack_bonus=2)
+    b_spec = make_combatant("b")
+    a = make_state(a_spec, "players", (1, 1))
+    b = make_state(b_spec, "monsters", (1, 2))
+    engine = make_engine([12, 12, 12, 12, 12], [a, b])
+    for _ in range(5):
+        engine._execute_maneuver(a, b, "sunder")
+    assert b.hp == 6
+    assert "b-w" in b.weapon_broken
+    assert engine.weapon_for(b, a) is None
+    assert any(c.condition.name == "disarmed" for c in b.active_conditions)