diff --git a/test/spec/svg/lines.js b/test/spec/svg/lines.js
index b4b892b3f..f464929db 100644
--- a/test/spec/svg/lines.js
+++ b/test/spec/svg/lines.js
@@ -2,7 +2,8 @@ describe("iD.svg.Lines", function () {
     var surface,
         projection = d3.geo.projection(function(x, y) { return [x, y]; })
             .clipExtent([[0, 0], [Infinity, Infinity]]),
-        filter = d3.functor(true);
+        all = d3.functor(true),
+        none = d3.functor(false);
 
     beforeEach(function () {
         surface = d3.select(document.createElementNS('http://www.w3.org/2000/svg', 'svg'))
@@ -15,7 +16,7 @@ describe("iD.svg.Lines", function () {
             line = iD.Way({nodes: [a.id, b.id]}),
             graph = iD.Graph([a, b, line]);
 
-        surface.call(iD.svg.Lines(projection), graph, [line], filter);
+        surface.call(iD.svg.Lines(projection), graph, [line], all);
 
         expect(surface.select('path.way')).to.be.classed('way');
         expect(surface.select('path.line')).to.be.classed('line');
@@ -27,7 +28,7 @@ describe("iD.svg.Lines", function () {
             line = iD.Way({nodes: [a.id, b.id], tags: {highway: 'residential'}}),
             graph = iD.Graph([a, b, line]);
 
-        surface.call(iD.svg.Lines(projection), graph, [line], filter);
+        surface.call(iD.svg.Lines(projection), graph, [line], all);
 
         expect(surface.select('.line')).to.be.classed('tag-highway');
         expect(surface.select('.line')).to.be.classed('tag-highway-residential');
@@ -40,7 +41,7 @@ describe("iD.svg.Lines", function () {
             relation = iD.Relation({members: [{id: line.id}], tags: {type: 'multipolygon', natural: 'wood'}}),
             graph = iD.Graph([a, b, line, relation]);
 
-        surface.call(iD.svg.Lines(projection), graph, [line], filter);
+        surface.call(iD.svg.Lines(projection), graph, [line], all);
 
         expect(surface.select('.stroke')).to.be.classed('tag-natural-wood');
     });
@@ -53,7 +54,7 @@ describe("iD.svg.Lines", function () {
             r = iD.Relation({members: [{id: w.id}], tags: {type: 'multipolygon'}}),
             graph = iD.Graph([a, b, c, w, r]);
 
-        surface.call(iD.svg.Lines(projection), graph, [w], filter);
+        surface.call(iD.svg.Lines(projection), graph, [w], all);
 
         expect(surface.select('.stroke')).to.be.classed('tag-natural-wood');
     });
@@ -67,7 +68,7 @@ describe("iD.svg.Lines", function () {
             r = iD.Relation({members: [{id: o.id, role: 'outer'}, {id: i.id, role: 'inner'}], tags: {type: 'multipolygon'}}),
             graph = iD.Graph([a, b, c, o, i, r]);
 
-        surface.call(iD.svg.Lines(projection), graph, [i], filter);
+        surface.call(iD.svg.Lines(projection), graph, [i], all);
 
         expect(surface.select('.stroke')).to.be.classed('tag-natural-wood');
     });
@@ -80,8 +81,54 @@ describe("iD.svg.Lines", function () {
     //         .append('path')
     //         .attr('class', 'other');
 
-    //     surface.call(iD.svg.Lines(projection), graph, [line], filter);
+    //     surface.call(iD.svg.Lines(projection), graph, [line], all);
 
     //     expect(surface.selectAll('.other')[0].length).to.equal(1);
     // });
+
+    describe("z-indexing", function() {
+        var graph = iD.Graph([
+                iD.Node({id: 'a', loc: [0, 0]}),
+                iD.Node({id: 'b', loc: [1, 1]}),
+                iD.Node({id: 'c', loc: [0, 0]}),
+                iD.Node({id: 'd', loc: [1, 1]}),
+                iD.Way({id: 'lo', tags: {highway: 'residential', tunnel: 'yes'}, nodes: ['a', 'b']}),
+                iD.Way({id: 'hi', tags: {highway: 'residential', bridge: 'yes'}, nodes: ['c', 'd']})
+            ]);
+
+        it("stacks higher lines above lower ones in a single render", function () {
+            surface.call(iD.svg.Lines(projection), graph, [graph.entity('lo'), graph.entity('hi')], none);
+
+            var selection = surface.selectAll('g.line-stroke > path.line');
+            expect(selection[0][0].__data__.id).to.eql('lo');
+            expect(selection[0][1].__data__.id).to.eql('hi');
+        });
+
+        it("stacks higher lines above lower ones in a single render (reverse)", function () {
+            surface.call(iD.svg.Lines(projection), graph, [graph.entity('hi'), graph.entity('lo')], none);
+
+            var selection = surface.selectAll('g.line-stroke > path.line');
+            expect(selection[0][0].__data__.id).to.eql('lo');
+            expect(selection[0][1].__data__.id).to.eql('hi');
+        });
+
+        it("stacks higher lines above lower ones in separate renders", function () {
+            surface.call(iD.svg.Lines(projection), graph, [graph.entity('lo')], none);
+            surface.call(iD.svg.Lines(projection), graph, [graph.entity('hi')], none);
+
+            var selection = surface.selectAll('g.line-stroke > path.line');
+            expect(selection[0][0].__data__.id).to.eql('lo');
+            expect(selection[0][1].__data__.id).to.eql('hi');
+        });
+
+        it("stacks higher lines above lower in separate renders (reverse)", function () {
+            surface.call(iD.svg.Lines(projection), graph, [graph.entity('hi')], none);
+            surface.call(iD.svg.Lines(projection), graph, [graph.entity('lo')], none);
+
+            var selection = surface.selectAll('g.line-stroke > path.line');
+            expect(selection[0][0].__data__.id).to.eql('lo');
+            expect(selection[0][1].__data__.id).to.eql('hi');
+        });
+    });
+
 });