Fix default to Null for feature-state expressions.

1 files changed, 2 insertions, 1 deletions

diff --git a/src/mbgl/style/expression/compound_expression.cpp b/src/mbgl/style/expression/compound_expression.cpp
index 3e01ad593..f810ddbe9 100644
--- a/src/mbgl/style/expression/compound_expression.cpp
+++ b/src/mbgl/style/expression/compound_expression.cpp
@@ -410,12 +410,13 @@ std::unordered_map<std::string, CompoundExpressionRegistry::Definition> initiali
     });
 
     define("feature-state", [](const EvaluationContext& params, const std::string& key) -> Result<Value> {
-        if (!params.feature || !params.featureState) {
+        if (!params.feature) {
             return EvaluationError {
                 "Feature state data is unavailable in the current evaluation context."
             };
         }
 
+        if (!params.featureState) { return Null; }
         auto statePair = params.featureState->find(key);
         if (statePair == params.featureState->end()) {
             return Null;