unit tests - add 'ensure original ordering in geojson.input' test ref #3182

test/data

@@ -1 +1 @@
-Subproject commit 3161747e4a47aea0a5f968caf3443e8fdf298772
+Subproject commit 94fa33e08b81686d85d712afee0b12d4e78f7a0a

test/unit/datasource/geojson.cpp

@@ -503,7 +503,7 @@ TEST_CASE("geojson") {
 
             for (auto cache_features : {true,false})
             {
-                params["cache_features"] = false;
+                params["cache_features"] = cache_features;
                 auto ds = mapnik::datasource_cache::instance().create(params);
                 auto fields = ds->get_descriptor().get_descriptors();
                 mapnik::query query(ds->envelope());
@@ -573,5 +573,61 @@ TEST_CASE("geojson") {
                 }
             }
         }
+
+        SECTION("GeoJSON ensure original feature ordering is preserved")
+        {
+            mapnik::parameters params;
+            params["type"] = "geojson";
+
+            std::string filename("./test/data/json/ordered.json");
+            params["file"] = filename;
+
+            // cleanup in the case of a failed previous run
+            if (mapnik::util::exists(filename + ".index"))
+            {
+                mapnik::util::remove(filename + ".index");
+            }
+
+            for (auto create_index : { true, false })
+            {
+                if (create_index)
+                {
+                    CHECK(!mapnik::util::exists(filename + ".index"));
+                    int ret = create_disk_index(filename);
+                    int ret_posix = (ret >> 8) & 0x000000ff;
+                    INFO(ret);
+                    INFO(ret_posix);
+                    CHECK(mapnik::util::exists(filename + ".index"));
+                }
+
+                for (auto cache_features : {true, false})
+                {
+                    params["cache_features"] = cache_features;
+                    auto ds = mapnik::datasource_cache::instance().create(params);
+                    REQUIRE(bool(ds));
+                    auto fields = ds->get_descriptor().get_descriptors();
+                    mapnik::query query(ds->envelope());
+                    for (auto const& field : fields)
+                    {
+                        query.add_property_name(field.get_name());
+                    }
+                    auto features = ds->features(query);
+                    auto feature = features->next();
+                    mapnik::value_integer count = 0;
+                    while (feature != nullptr)
+                    {
+                        // ids are in ascending order, starting from 1
+                        mapnik::value val= feature->get("id");
+                        REQUIRE(val.get<mapnik::value_integer>() == ++count);
+                        feature = features->next();
+                    }
+                }
+                // cleanup
+                if (create_index && mapnik::util::exists(filename + ".index"))
+                {
+                    mapnik::util::remove(filename + ".index");
+                }
+            }
+        }
     }
 }