do not emit turns on ferries

include/extractor/guidance/suppress_mode_handler.hpp

@@ -0,0 +1,44 @@
+#ifndef OSRM_EXTRACTOR_GUIDANCE_SUPPRESS_MODE_HANDLER_HPP_
+#define OSRM_EXTRACTOR_GUIDANCE_SUPPRESS_MODE_HANDLER_HPP_
+
+#include "extractor/guidance/constants.hpp"
+#include "extractor/guidance/intersection.hpp"
+#include "extractor/guidance/intersection_generator.hpp"
+#include "extractor/guidance/intersection_handler.hpp"
+#include "extractor/travel_mode.hpp"
+#include "util/node_based_graph.hpp"
+
+namespace osrm
+{
+namespace extractor
+{
+namespace guidance
+{
+
+class SuppressModeHandler final : public IntersectionHandler
+{
+  public:
+    SuppressModeHandler(const IntersectionGenerator &intersection_generator,
+                        const util::NodeBasedDynamicGraph &node_based_graph,
+                        const std::vector<QueryNode> &node_info_list,
+                        const util::NameTable &name_table,
+                        const SuffixTable &street_name_suffix_table);
+
+    ~SuppressModeHandler() override final = default;
+
+    bool canProcess(const NodeID /*nid*/,
+                    const EdgeID via_eid,
+                    const Intersection &intersection) const override final;
+
+    Intersection operator()(const NodeID nid,
+                            const EdgeID via_eid,
+                            Intersection intersection) const override final;
+
+    using SuppressModeListT = std::array<osrm::extractor::TravelMode, 2>;
+};
+
+} // namespace osrm
+} // namespace extractor
+} // namespace guidance
+
+#endif /* OSRM_EXTRACTOR_GUIDANCE_SUPPRESS_MODE_HANDLER_HPP_ */

include/extractor/guidance/turn_analysis.hpp

@@ -8,6 +8,7 @@
 #include "extractor/guidance/motorway_handler.hpp"
 #include "extractor/guidance/roundabout_handler.hpp"
 #include "extractor/guidance/sliproad_handler.hpp"
+#include "extractor/guidance/suppress_mode_handler.hpp"
 #include "extractor/guidance/turn_classification.hpp"
 #include "extractor/guidance/turn_handler.hpp"
 #include "extractor/query_node.hpp"
@@ -86,6 +87,7 @@ class TurnAnalysis
     const MotorwayHandler motorway_handler;
     const TurnHandler turn_handler;
     const SliproadHandler sliproad_handler;
+    const SuppressModeHandler suppress_mode_handler;
 
     // Utility function, setting basic turn types. Prepares for normal turn handling.
     Intersection