fix: Exclude identities when PERCENTAGE_SPLIT trait is undefined

flag_engine/segments/evaluator.py

@@ -228,25 +228,57 @@ def context_matches_condition(
     condition: SegmentCondition,
     segment_key: SupportsStr,
 ) -> bool:
-    context_value = (
-        get_context_value(context, condition_property)
-        if (condition_property := condition.get("property"))
-        else None
-    )
-
-    if condition["operator"] == constants.PERCENTAGE_SPLIT:
-        if context_value is not None:
-            object_ids = [segment_key, context_value]
+    context_value: ContextValue
+    condition_property = condition["property"]
+    condition_operator = condition["operator"]
+
+    if condition_operator == constants.PERCENTAGE_SPLIT and (not condition_property):
+        # Currently, the only supported condition with a blank property
+        # is percentage split.
+        # In this case, we use the identity key as context value.
+        # This is mainly to support legacy segments created before
+        # we introduced JSONPath support.
+        context_value = _get_identity_key(context)
+    else:
+        context_value = get_context_value(context, condition_property)
+
+    if condition_operator == constants.IN:
+        if isinstance(segment_value := condition["value"], list):
+            in_values = segment_value
         else:
-            object_ids = [segment_key, get_context_value(context, "$.identity.key")]
+            try:
+                in_values = json.loads(segment_value)
+                # Only accept JSON lists.
+                # Ideally, we should use something like pydantic.TypeAdapter[list[str]],
+                # but we aim to ditch the pydantic dependency in the future.
+                if not isinstance(in_values, list):
+                    raise ValueError
+            except ValueError:
+                in_values = segment_value.split(",")
+        in_values = [str(value) for value in in_values]
+        # Guard against comparing boolean values to numeric strings.
+        if isinstance(context_value, int) and not (
+            context_value is True or context_value is False
+        ):
+            context_value = str(context_value)
+        return context_value in in_values
 
-        float_value = float(condition["value"])
+    if condition_operator == constants.PERCENTAGE_SPLIT:
+        if context_value is None:
+            return False
+
+        object_ids = [segment_key, context_value]
+
+        try:
+            float_value = float(condition["value"])
+        except ValueError:
+            return False
         return get_hashed_percentage_for_object_ids(object_ids) <= float_value
 
-    if condition["operator"] == constants.IS_NOT_SET:
+    if condition_operator == constants.IS_NOT_SET:
         return context_value is None
 
-    if condition["operator"] == constants.IS_SET:
+    if condition_operator == constants.IS_SET:
         return context_value is not None
 
     return (
@@ -368,6 +400,14 @@ def inner(
     return inner
 
 
+def _get_identity_key(
+    context: EvaluationContext,
+) -> typing.Optional[str]:
+    if identity_context := context.get("identity"):
+        return identity_context.get("key")
+    return None
+
+
 MATCHERS_BY_OPERATOR: typing.Dict[
     ConditionOperator, typing.Callable[[typing.Optional[str], ContextValue], bool]
 ] = {