[core] fix crash when trying to parse legacy filters

Legacy filters aren't part of the style specification, but you can generate them by parsing a legacy filter in a stylesheet, and obtaining the parsed Filter and serializing it.

1 files changed, 4 insertions, 0 deletions

diff --git a/test/style/filter.test.cpp b/test/style/filter.test.cpp
index c8f1d3b808..bac3801223 100644
--- a/test/style/filter.test.cpp
+++ b/test/style/filter.test.cpp
@@ -192,3 +192,7 @@ TEST(Filter, ZoomExpressionNested) {
     ASSERT_TRUE(filter(R"(["==", ["get", "two"], ["zoom"]])", {{"two", int64_t(2)}}, {}, FeatureType::Point, {}, 2.0f));
     ASSERT_FALSE(filter(R"(["==", ["get", "two"], ["+", ["zoom"], 1]])", {{"two", int64_t(2)}}, {}, FeatureType::Point, {}, 2.0f));
 }
+
+TEST(Filter, Internal) {
+    filter(R"(["filter-==","class","snow"])");
+}