Optionally include ids members of modified relations in extantIDs

(closes #6273)

modules/core/difference.js

@@ -73,14 +73,30 @@ export function coreDifference(base, head) {
     _diff.didChange = _didChange;
 
 
-    _diff.extantIDs = function extantIDs() {
-        var result = [];
+    // pass true to include affected relation members
+    _diff.extantIDs = function extantIDs(includeRelMembers) {
+        var result = new Set();
         Object.keys(_changes).forEach(function(id) {
             if (_changes[id].head) {
-                result.push(id);
+                result.add(id);
+            }
+
+            var h = _changes[id].head;
+            var b = _changes[id].base;
+            var entity = h || b;
+
+            if (includeRelMembers && entity.type === 'relation') {
+                var mh = h ? h.members.map(function(m) { return m.id; }) : [];
+                var mb = b ? b.members.map(function(m) { return m.id; }) : [];
+                utilArrayUnion(mh, mb).forEach(function(memberID) {
+                    if (head.hasEntity(memberID)) {
+                        result.add(memberID);
+                    }
+                });
             }
         });
-        return result;
+
+        return Array.from(result);
     };
 
 

modules/core/validator.js

@@ -292,8 +292,12 @@ export function coreValidator(context) {
 
             if (entity.type === 'node') {   // include parent ways
                 graph.parentWays(entity).forEach(function(parentWay) {
-                    checkParentRels.push(parentWay);
                     acc.add(parentWay.id);
+                    checkParentRels.push(parentWay);
+                });
+            } else if (entity.type === 'relation') {   // include members
+                entity.members.forEach(function(member) {
+                    acc.add(member.id);
                 });
             }
 
@@ -356,8 +360,8 @@ export function coreValidator(context) {
             }
         }
 
-        var entityIDs = difference.extantIDs();  // created and modified
-        difference.deleted().forEach(uncacheEntityID);   // deleted
+        var entityIDs = difference.extantIDs(true);   // created/modified (true = w/relation members)
+        difference.deleted().forEach(uncacheEntityID);  // deleted
 
         validator.validateEntities(entityIDs);   // dispatches 'validated'
     };