fix(combat): single roll to escape grapple

src/pf1e_simulator/combat.py

@@ -703,15 +703,22 @@ class CombatEngine:
     def resolve_skill(
         self, state: CombatantState, skill: str, dc: int
     ) -> SaveResult:
-        """Roll a skill check against ``dc``.
+        """Roll a skill check against ``dc``."""
 
-        """
+        roll = self._rng.d20()
+        bonus = self._skill_static_bonus(state, skill)
+        total = roll + bonus
+        # Natural 1/20 are not auto-fail/success for skills
+        success = total >= dc
+        return SaveResult(success=success, roll=roll, total=total, dc=dc)
+
+    def _skill_static_bonus(self, state: CombatantState, skill: str) -> int:
+        """Return a skill's static bonus (no d20). Shared by resolve_skill."""
         skill_spec = PREDEFINED_SKILLS.get(skill)
         if skill_spec is None:
             msg = f"Unknown skill: {skill}"
             raise ValueError(msg)
 
-        roll = self._rng.d20()
         skill_rank = state.combatant.skills.get(skill, None)
         rank = skill_rank.rank if skill_rank else 0
         # Class skill bonus
@@ -728,10 +735,7 @@ class CombatEngine:
         ability_mod = (ability_score - 10) // 2
         # Effect/condition modifiers
         mod_bonus = resolve_modifiers(self._stat_modifiers(state, skill))
-        total = roll + rank + class_bonus + ability_mod + armor_penalty + mod_bonus
-        # Natural 1/20 are not auto-fail/success for skills
-        success = total >= dc
-        return SaveResult(success=success, roll=roll, total=total, dc=dc)
+        return rank + class_bonus + ability_mod + armor_penalty + mod_bonus
 
     def _roll_initiative(self) -> list[CombatantState]:
         rolls: dict[str, tuple[int, int]] = {}
@@ -1304,7 +1308,7 @@ class CombatEngine:
     ) -> None:
         escape_cmb = self._maneuver_cmb(state)
         escape_skill = (
-            self.resolve_skill(state, "escape_artist", 0).total
+            self._skill_static_bonus(state, "escape_artist")
             if hasattr(state.combatant, "skills") and "escape_artist" in state.combatant.skills
             else 0
         )

tests/test_maneuvers.py

@@ -8,6 +8,8 @@ it (effectively disarmed). See the plan task-12.
 from __future__ import annotations
 
 from pf1e_simulator.combat import CombatantState, CombatEngine
+from pf1e_simulator.conditions import CONDITIONS_BY_NAME
+from pf1e_simulator.effects import ActiveCondition
 from pf1e_simulator.grid import Grid
 from pf1e_simulator.map import MapSpec, TerrainType
 from pf1e_simulator.models import (
@@ -17,6 +19,7 @@ from pf1e_simulator.models import (
     Combatant,
     DamageComponent,
     Saves,
+    SkillRank,
 )
 from pf1e_simulator.rng import ScriptedRng
 
@@ -91,3 +94,25 @@ def test_sunder_destroys_weapon_and_disarms() -> None:
     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)
+
+
+def test_escape_from_grapple_consumes_single_d20() -> None:
+    a_spec = make_combatant("a", attack_bonus=2).model_copy(
+        update={"skills": {"escape_artist": SkillRank(rank=10)}}
+    )
+    b_spec = make_combatant("b")
+    a = make_state(a_spec, "players", (1, 1))
+    b = make_state(b_spec, "monsters", (1, 2))
+    a.active_conditions.append(
+        ActiveCondition(
+            condition=CONDITIONS_BY_NAME["grappled"],
+            rounds_left=1,
+            source="test",
+        )
+    )
+    a.grappled_with = b_spec.id
+    engine = make_engine([20], [a, b])
+    engine._maneuver_escape(a, b)
+    assert not engine._rng._queue
+    assert a.grappled_with is None
+    assert not any(c.condition.name == "grappled" for c in a.active_conditions)