diff -r efd9c589177a -r c0b4a8b5a012 toolkit/javascript/d3/test/core/selection-map-test.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/javascript/d3/test/core/selection-map-test.js	Thu Apr 10 14:20:23 2014 +0200
@@ -0,0 +1,47 @@
+require("../env");
+require("../../d3");
+
+var vows = require("vows"),
+    assert = require("assert");
+
+var suite = vows.describe("selection.map");
+
+suite.addBatch({
+  "select(body)": {
+    topic: function() {
+      return d3.select("body").html("");
+    },
+    "updates the data according to the map function": function(body) {
+      body.data([42]).map(function(d, i) { return d + i; });
+      assert.equal(document.body.__data__, 42);
+    },
+    "returns the current selection": function(body) {
+      assert.isTrue(body.map(function() { return 1; }) === body);
+    }
+  }
+});
+
+suite.addBatch({
+  "selectAll(div)": {
+    topic: function() {
+      return d3.select("body").html("").selectAll("div").data(d3.range(2)).enter().append("div");
+    },
+    "updates the data according to the map function": function(div) {
+      div.data([42, 43]).map(function(d, i) { return d + i; });
+      assert.equal(div[0][0].__data__, 42);
+      assert.equal(div[0][1].__data__, 44);
+    },
+    "returns the current selection": function(div) {
+      assert.isTrue(div.map(function() { return 1; }) === div);
+    },
+    "ignores null nodes": function(div) {
+      var some = d3.selectAll("div").data([42, 43]);
+      some[0][1] = null;
+      some.map(function() { return 1; });
+      assert.equal(div[0][0].__data__, 1);
+      assert.equal(div[0][1].__data__, 43);
+    }
+  }
+});
+
+suite.export(module);