Enable parse within expression

Add geometry type checker

2 files changed, 56 insertions, 5 deletions

diff --git a/include/mbgl/style/expression/expression.hpp b/include/mbgl/style/expression/expression.hpp
index 9893daa8c4..f19f64c1e7 100644
--- a/include/mbgl/style/expression/expression.hpp
+++ b/include/mbgl/style/expression/expression.hpp
@@ -1,11 +1,12 @@
 #pragma once
 
-#include <mbgl/util/optional.hpp>
-#include <mbgl/util/variant.hpp>
-#include <mbgl/util/color.hpp>
+#include <mbgl/style/expression/parsing_context.hpp>
 #include <mbgl/style/expression/type.hpp>
 #include <mbgl/style/expression/value.hpp>
-#include <mbgl/style/expression/parsing_context.hpp>
+#include <mbgl/tile/tile_id.hpp>
+#include <mbgl/util/color.hpp>
+#include <mbgl/util/optional.hpp>
+#include <mbgl/util/variant.hpp>
 
 #include <array>
 #include <vector>
@@ -53,8 +54,14 @@ public:
         return *this;
     };
 
+    EvaluationContext& withCanonicalTileID(const mbgl::CanonicalTileID& canonical_) noexcept {
+        canonical = canonical_;
+        return *this;
+    };
+
     optional<float> zoom;
     optional<mbgl::Value> accumulated;
+    optional<mbgl::CanonicalTileID> canonical;
     GeometryTileFeature const * feature = nullptr;
     optional<double> colorRampParameter;
     // Contains formatted section object, std::unordered_map<std::string, Value>.
@@ -160,7 +167,8 @@ enum class Kind : int32_t {
     FormatExpression,
     FormatSectionOverride,
     NumberFormat,
-    ImageExpression
+    ImageExpression,
+    Within
 };
 
 class Expression {
diff --git a/include/mbgl/style/expression/within.hpp b/include/mbgl/style/expression/within.hpp
new file mode 100644
index 0000000000..5e2b5e0671
--- /dev/null
+++ b/include/mbgl/style/expression/within.hpp
@@ -0,0 +1,43 @@
+#pragma once
+
+#include <mbgl/style/conversion.hpp>
+#include <mbgl/style/expression/expression.hpp>
+#include <mbgl/style/expression/parsing_context.hpp>
+#include <mbgl/util/geojson.hpp>
+
+#include <memory>
+
+namespace mbgl {
+namespace style {
+namespace expression {
+
+class Within : public Expression {
+public:
+    Within(GeoJSON& geojson) : Expression(Kind::Within, type::Boolean), geoJSONSource(geojson) {}
+
+    EvaluationResult evaluate(const EvaluationContext&) const override;
+
+    static ParseResult parse(const mbgl::style::conversion::Convertible&, ParsingContext&);
+
+    void eachChild(const std::function<void(const Expression&)>&) const override {}
+
+    bool operator==(const Expression& e) const override {
+        if (e.getKind() == Kind::Within) {
+            auto rhs = static_cast<const Within*>(&e);
+            return geoJSONSource == rhs->geoJSONSource;
+        }
+        return false;
+    }
+
+    std::vector<optional<Value>> possibleOutputs() const override { return {{false}}; }
+
+    mbgl::Value serialize() const override;
+    std::string getOperator() const override { return "Within"; }
+
+private:
+    GeoJSON geoJSONSource;
+};
+
+} // namespace expression
+} // namespace style
+} // namespace mbgl