diff -r efd9c589177a -r c0b4a8b5a012 toolkit/javascript/d3/test/core/merge-test.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/javascript/d3/test/core/merge-test.js	Thu Apr 10 14:20:23 2014 +0200
@@ -0,0 +1,27 @@
+require("../env");
+require("../../d3");
+
+var vows = require("vows"),
+    assert = require("assert");
+
+var suite = vows.describe("d3.merge");
+
+suite.addBatch({
+  "merge": {
+    "merges an array of arrays": function() {
+      var a = {}, b = {}, c = {}, d = {}, e = {}, f = {};
+      assert.deepEqual(d3.merge([[a], [b, c], [d, e, f]]), [a, b, c, d, e, f]);
+    },
+    "returns a new array": function() {
+      var input = [[1, 2, 3], [4, 5], [6]];
+      assert.isFalse(d3.merge(input) === input);
+    },
+    "does not modify the input arrays": function() {
+      var input = [[1, 2, 3], [4, 5], [6]];
+      d3.merge(input);
+      assert.deepEqual(input, [[1, 2, 3], [4, 5], [6]]);
+    }
+  }
+});
+
+suite.export(module);