From 0f289f1865d8a67edc11be52d0d23a0cadf34849 Mon Sep 17 00:00:00 2001
From: Bryan Housel <bryan@7thposition.com>
Date: Thu, 12 Mar 2015 13:59:48 -0400
Subject: [PATCH] Prevent no-match parent relations from breaking getMatches

(e.g. a site relation with a fence in it)
Also, updated the test graph to contain one of these.
see https://github.com/openstreetmap/iD/pull/2554#issuecomment-78517442
---
 js/id/renderer/features.js     |  6 ++++--
 test/spec/renderer/features.js | 14 +++++++++++++-
 2 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/js/id/renderer/features.js b/js/id/renderer/features.js
index 9793025d48f..75c6eac72da 100644
--- a/js/id/renderer/features.js
+++ b/js/id/renderer/features.js
@@ -305,8 +305,10 @@ iD.Features = function(context) {
                             var parents = features.getParents(entity, resolver, geometry);
                             if (parents.length === 1) {
                                 var pkey = iD.Entity.key(parents[0]);
-                                matches = _.clone(_cache[pkey].matches);
-                                continue;
+                                if (_cache[pkey] && _cache[pkey].matches) {
+                                    matches = _.clone(_cache[pkey].matches);
+                                    continue;
+                                }
                             }
                         }
                     }
diff --git a/test/spec/renderer/features.js b/test/spec/renderer/features.js
index 35a615f4eaf..01c2155afa2 100644
--- a/test/spec/renderer/features.js
+++ b/test/spec/renderer/features.js
@@ -135,6 +135,8 @@ describe('iD.Features', function() {
             iD.Way({id: 'scrub', tags: {area: 'yes', natural: 'scrub'}, version: 1}),
             iD.Way({id: 'industrial', tags: {area: 'yes', landuse: 'industrial'}, version: 1}),
             iD.Way({id: 'parkinglot', tags: {area: 'yes', amenity: 'parking', parking: 'surface'}, version: 1}),
+
+            // Landuse with hole
             iD.Way({id: 'inner', version: 1}),
             iD.Way({id: 'outer', version: 1}),
             iD.Relation({id: 'retail', tags: {landuse: 'retail', type: 'multipolygon'},
@@ -175,7 +177,17 @@ describe('iD.Features', function() {
 
             // Others
             iD.Way({id: 'fence', tags: {barrier: 'fence'}, version: 1}),
-            iD.Way({id: 'pipeline', tags: {man_made: 'pipeline'}, version: 1})
+            iD.Way({id: 'pipeline', tags: {man_made: 'pipeline'}, version: 1}),
+
+            // Site relation
+            iD.Relation({id: 'site', tags: {type: 'site'},
+                    members: [
+                        {id: 'fence', role: 'perimeter'},
+                        {id: 'building_yes'}
+                    ],
+                    version: 1
+                }),
+
         ]),
         all = _.values(graph.base().entities);