[planner] cache primitive offers

masque/builder/planner/planner.py

@@ -288,6 +288,10 @@ class Solver:
     def __init__(self, request: RouteRequest) -> None:
         self.request = request
         self.eval_cache: dict[tuple[int, float, str | None, str | None, str, str, PrimitiveKind | None], SelectedPrimitive] = {}
+        self.offer_cache: dict[
+            tuple[PrimitiveKind, str | None, str | None, tuple[tuple[str, Any], ...]],
+            tuple[PrimitiveOffer, ...],
+            ] = {}
         self.order = 0
 
     def solve(self) -> Candidate:
@@ -384,8 +388,19 @@ class Solver:
         kwargs.pop('out_ptype', None)
         if extra:
             kwargs.update(extra)
+        try:
+            cache_key = (kind, in_ptype, out_ptype, tuple(sorted(kwargs.items())))
+            hash(cache_key)
+        except TypeError:
             return self.request.tool.primitive_offers(kind, in_ptype=in_ptype, out_ptype=out_ptype, **kwargs)
 
+        cached = self.offer_cache.get(cache_key)
+        if cached is not None:
+            return cached
+        offers = self.request.tool.primitive_offers(kind, in_ptype=in_ptype, out_ptype=out_ptype, **kwargs)
+        self.offer_cache[cache_key] = offers
+        return offers
+
     def evaluate(
             self,
             offer: PrimitiveOffer,