1 files changed, 50 insertions, 19 deletions

diff --git a/src/mbgl/style/sources/geojson_source_impl.cpp b/src/mbgl/style/sources/geojson_source_impl.cpp
index 24ac1d7976..c3cb942709 100644
--- a/src/mbgl/style/sources/geojson_source_impl.cpp
+++ b/src/mbgl/style/sources/geojson_source_impl.cpp
@@ -1,6 +1,7 @@
 #include <mbgl/style/sources/geojson_source_impl.hpp>
-#include <mbgl/util/constants.hpp>
 #include <mbgl/tile/tile_id.hpp>
+#include <mbgl/util/constants.hpp>
+#include <mbgl/util/feature.hpp>
 #include <mbgl/util/string.hpp>
 
 #include <mapbox/geojsonvt.hpp>
@@ -13,9 +14,9 @@ namespace style {
 
 class GeoJSONVTData : public GeoJSONData {
 public:
-    GeoJSONVTData(const GeoJSON& geoJSON,
-                  const mapbox::geojsonvt::Options& options)
-        : impl(geoJSON, options) {}
+    GeoJSONVTData(const GeoJSON& geoJSON, const mapbox::geojsonvt::Options& options)
+        : impl(geoJSON, options) {
+    }
 
     mapbox::feature::feature_collection<int16_t> getTile(const CanonicalTileID& tileID) final {
         return impl.getTile(tileID.z, tileID.x, tileID.y).features;
@@ -25,9 +26,8 @@ public:
         return {};
     }
 
-    mapbox::feature::feature_collection<double> getLeaves(const std::uint32_t,
-                                                           const std::uint32_t,
-                                                           const std::uint32_t) final {
+    mapbox::feature::feature_collection<double>
+    getLeaves(const std::uint32_t, const std::uint32_t, const std::uint32_t) final {
         return {};
     }
 
@@ -43,7 +43,8 @@ class SuperclusterData : public GeoJSONData {
 public:
     SuperclusterData(const mapbox::feature::feature_collection<double>& features,
                      const mapbox::supercluster::Options& options)
-        : impl(features, options) {}
+        : impl(features, options) {
+    }
 
     mapbox::feature::feature_collection<int16_t> getTile(const CanonicalTileID& tileID) final {
         return impl.getTile(tileID.z, tileID.x, tileID.y);
@@ -54,8 +55,8 @@ public:
     }
 
     mapbox::feature::feature_collection<double> getLeaves(const std::uint32_t cluster_id,
-                                                           const std::uint32_t limit,
-                                                           const std::uint32_t offset) final {
+                                                          const std::uint32_t limit,
+                                                          const std::uint32_t offset) final {
         return impl.getLeaves(cluster_id, limit, offset);
     }
 
@@ -67,23 +68,53 @@ private:
     mapbox::supercluster::Supercluster impl;
 };
 
-GeoJSONSource::Impl::Impl(std::string id_, GeoJSONOptions options_)
-    : Source::Impl(SourceType::GeoJSON, std::move(id_)),
-      options(std::move(options_)) {
+template <class T>
+T evaluateFeature(const mapbox::feature::feature<double>& f,
+                  const std::shared_ptr<expression::Expression>& expression,
+                  optional<T> accumulated = nullopt) {
+    const expression::EvaluationResult result = expression->evaluate(accumulated, f);
+    if (result) {
+        optional<T> typed = expression::fromExpressionValue<T>(*result);
+        if (typed) {
+            return std::move(*typed);
+        }
+    }
+    return T();
+}
+
+GeoJSONSource::Impl::Impl(std::string id_, optional<GeoJSONOptions> options_)
+    : Source::Impl(SourceType::GeoJSON, std::move(id_)) {
+    options = options_ ? std::move(*options_) : GeoJSONOptions{};
 }
 
 GeoJSONSource::Impl::Impl(const Impl& other, const GeoJSON& geoJSON)
-    : Source::Impl(other),
-      options(other.options) {
+    : Source::Impl(other), options(other.options) {
     constexpr double scale = util::EXTENT / util::tileSize;
-
-    if (options.cluster
-        && geoJSON.is<mapbox::feature::feature_collection<double>>()
-        && !geoJSON.get<mapbox::feature::feature_collection<double>>().empty()) {
+    if (options.cluster && geoJSON.is<mapbox::feature::feature_collection<double>>() &&
+        !geoJSON.get<mapbox::feature::feature_collection<double>>().empty()) {
         mapbox::supercluster::Options clusterOptions;
         clusterOptions.maxZoom = options.clusterMaxZoom;
         clusterOptions.extent = util::EXTENT;
         clusterOptions.radius = ::round(scale * options.clusterRadius);
+        Feature feature;
+        clusterOptions.map = [&](const PropertyMap& properties) -> PropertyMap {
+            PropertyMap ret{};
+            for (const auto& p : options.clusterProperties) {
+                feature.properties = properties;
+                ret[p.first] = evaluateFeature<Value>(feature, p.second.first);
+            }
+            return ret;
+        };
+        clusterOptions.reduce = [&](PropertyMap& toReturn, const PropertyMap& toFill) {
+            for (const auto& p : options.clusterProperties) {
+                if (toFill.count(p.first) == 0) {
+                    continue;
+                }
+                feature.properties = toFill;
+                optional<Value> accumulated(toReturn[p.first]);
+                toReturn[p.first] = evaluateFeature<Value>(feature, p.second.second, accumulated);
+            }
+        };
         data = std::make_shared<SuperclusterData>(
             geoJSON.get<mapbox::feature::feature_collection<double>>(), clusterOptions);
     } else {