Allow --set-attribute to override existing attribute values (#123)

* Allow --set-attribute to override existing attribute values

* Bump version number

CHANGELOG.md

@@ -1,3 +1,7 @@
+# 2.28.1
+
+* Allow --set-attribute to override an existing attribute value
+
 # 2.28.0
 
 * Add --preserve-point-density-threshold option to reduce blank areas of the map at low zooms

serial.cpp

@@ -630,9 +630,20 @@ int serialize_feature(struct serialization_state *sst, serial_feature &sf) {
 	}
 
 	for (auto &kv : set_attributes) {
+		bool found = false;
+		for (size_t i = 0; i < sf.full_keys.size(); i++) {
+			if (sf.full_keys[i] == kv.first) {
+				sf.full_values[i] = kv.second;
+				found = true;
+				break;
+			}
+		}
+
+		if (!found) {
 			sf.full_keys.push_back(kv.first);
 			sf.full_values.push_back(kv.second);
 		}
+	}
 
 	for (ssize_t i = (ssize_t) sf.full_keys.size() - 1; i >= 0; i--) {
 		coerce_value(sf.full_keys[i], sf.full_values[i].type, sf.full_values[i].s, sst->attribute_types);

version.hpp

@@ -1,6 +1,6 @@
 #ifndef VERSION_HPP
 #define VERSION_HPP
 
-#define VERSION "v2.28.0"
+#define VERSION "v2.28.1"
 
 #endif