diff -r efd9c589177a -r c0b4a8b5a012 toolkit/javascript/d3/test/geo/mercator-test.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/javascript/d3/test/geo/mercator-test.js	Thu Apr 10 14:20:23 2014 +0200
@@ -0,0 +1,57 @@
+require("../env");
+require("../../d3");
+require("../../d3.geo");
+
+var vows = require("vows"),
+    assert = require("assert");
+
+var suite = vows.describe("d3.geo.mercator");
+
+suite.addBatch({
+  "mercator": {
+    topic: function() {
+      return d3.geo.mercator().translate([0, 0]).scale(100);
+    },
+    "Arctic": function(mercator) {
+      var coords = mercator([0, 85]);
+      assert.inDelta(coords[0], 0, 1e-6);
+      assert.inDelta(coords[1], -49.8362085, 1e-6);
+      var lonlat = mercator.invert(coords);
+      assert.inDelta(lonlat[0], 0, 1e-6);
+      assert.inDelta(lonlat[1], 85, 1e-6);
+    },
+    "Antarctic": function(mercator) {
+      var coords = mercator([0, -85]);
+      assert.inDelta(coords[0], 0, 1e-6);
+      assert.inDelta(coords[1], 49.8362085, 1e-6);
+      var lonlat = mercator.invert(coords);
+      assert.inDelta(lonlat[0], 0, 1e-6);
+      assert.inDelta(lonlat[1], -85, 1e-6);
+    },
+    "Hawaii": function(mercator) {
+      var coords = mercator([-180, 0]);
+      assert.inDelta(coords[0], -50, 1e-6);
+      assert.inDelta(coords[1], 0, 1e-6);
+      var lonlat = mercator.invert(coords);
+      assert.inDelta(lonlat[0], -180, 1e-6);
+      assert.inDelta(lonlat[1], 0, 1e-6);
+    },
+    "Phillipines": function(mercator) {
+      var coords = mercator([180, 0]);
+      assert.inDelta(coords[0], 50, 1e-6);
+      assert.inDelta(coords[1], 0, 1e-6);
+      var lonlat = mercator.invert(coords);
+      assert.inDelta(lonlat[0], 180, 1e-6);
+      assert.inDelta(lonlat[1], 0, 1e-6);
+    },
+    "Inversion works for non-zero translation": function() {
+      var mercator = d3.geo.mercator().translate([123, 99]).scale(100),
+          coords = mercator([0, 85]),
+          lonlat = mercator.invert(coords);
+      assert.inDelta(lonlat[0], 0, 1e-6);
+      assert.inDelta(lonlat[1], 85, 1e-6);
+    }
+  }
+});
+
+suite.export(module);