From f64c2df17ff81421eb9e9f9ccf2339c0153f2e52 Mon Sep 17 00:00:00 2001
From: John Firebaugh <john.firebaugh@gmail.com>
Date: Thu, 17 Jan 2013 10:40:14 -0800
Subject: [PATCH] Return null rather than empty string

Empty string still generates the error 'Problem parsing d=""',
while null results in no 'd' attribute at all.
---
 js/id/svg.js     | 2 +-
 test/spec/svg.js | 7 +++++++
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/js/id/svg.js b/js/id/svg.js
index bf73f32b8..e2b1dc2ad 100644
--- a/js/id/svg.js
+++ b/js/id/svg.js
@@ -19,7 +19,7 @@ iD.svg = {
             }
 
             if (entity.nodes.length === 0) {
-                return (cache[entity.id] = '');
+                return (cache[entity.id] = null);
             }
 
             return (cache[entity.id] =
diff --git a/test/spec/svg.js b/test/spec/svg.js
index bbb78c990..265562071 100644
--- a/test/spec/svg.js
+++ b/test/spec/svg.js
@@ -7,4 +7,11 @@ describe("iD.svg.LineString", function () {
 
         expect(iD.svg.LineString(projection)(way)).to.equal("M0,0L2,3");
     });
+
+    it("returns null for an entity with no nodes", function () {
+        var way = iD.Way(),
+            projection = Object;
+
+        expect(iD.svg.LineString(projection)(way)).to.be.null;
+    });
 });