Optimize Some Statement Evaluation and Fix Correctness Mismatches

capa/engine.py

@@ -197,8 +197,12 @@ def evaluate(self, features: FeatureSet, short_circuit=True):
         capa.perf.counters["evaluate.feature.some"] += 1
 
         if short_circuit:
-            results = []
+            results: list[Result] = []
             satisfied_children_count = 0
+            if satisfied_children_count >= self.count:
+                # short circuit immediately if threshold is already met (e.g. count <= 0)
+                return Result(True, self, results)
+
             for child in self.children:
                 result = child.evaluate(features, short_circuit=short_circuit)
                 results.append(result)

tests/test_engine.py

@@ -105,6 +105,25 @@ def test_some():
     assert bool(Some(0, [Number(1)]).evaluate({Number(0): {ADDR1}})) is True
     assert bool(Some(1, [Number(1)]).evaluate({Number(0): {ADDR1}})) is False
 
+    # Test Some(0, []) correctness (should evaluate to True in both short-circuit modes)
+    assert Some(0, []).evaluate({Number(0): {ADDR1}}, short_circuit=True).success is True
+    assert Some(0, []).evaluate({Number(0): {ADDR1}}, short_circuit=False).success is True
+
+    # Test Some(0, [Child]) optimization (child must not be evaluated when short-circuit is True)
+    class TrackingFeature(Number):
+        def __init__(self, value):
+            super().__init__(value)
+            self.evaluated = False
+
+        def evaluate(self, features, short_circuit=True):
+            self.evaluated = True
+            return super().evaluate(features, short_circuit)
+
+    tracker = TrackingFeature(1)
+    res = Some(0, [tracker]).evaluate({Number(0): {ADDR1}}, short_circuit=True)
+    assert res.success is True
+    assert tracker.evaluated is False  # Must not be evaluated!
+
     assert bool(Some(2, [Number(1), Number(2), Number(3)]).evaluate({Number(0): {ADDR1}})) is False
     assert bool(Some(2, [Number(1), Number(2), Number(3)]).evaluate({Number(0): {ADDR1}, Number(1): {ADDR1}})) is False
     assert (