diff -r efd9c589177a -r c0b4a8b5a012 toolkit/javascript/d3/test/core/nest-test.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/javascript/d3/test/core/nest-test.js	Thu Apr 10 14:20:23 2014 +0200
@@ -0,0 +1,236 @@
+require("../env");
+require("../../d3");
+
+var vows = require("vows"),
+    assert = require("assert");
+
+var suite = vows.describe("d3.nest");
+
+suite.addBatch({
+  "entries": {
+    topic: function() {
+      return d3.nest;
+    },
+    "returns an array of each distinct key in arbitrary order": function(nest) {
+      var keys = nest()
+          .key(function(d) { return d.foo; })
+          .entries([{foo: 1}, {foo: 1}, {foo: 2}])
+          .map(function(d) { return d.key; })
+          .sort(d3.ascending);
+      assert.deepEqual(keys, ["1", "2"]);
+    },
+    "each entry is a key-values object, with values in input order": function(nest) {
+      var entries = nest()
+          .key(function(d) { return d.foo; })
+          .entries([{foo: 1, bar: 0}, {foo: 2}, {foo: 1, bar: 1}]);
+      assert.deepEqual(entries, [
+        {key: "1", values: [{foo: 1, bar: 0}, {foo: 1, bar: 1}]},
+        {key: "2", values: [{foo: 2}]}
+      ]);
+    },
+    "keys can be sorted using an optional comparator": function(nest) {
+      var keys = nest()
+          .key(function(d) { return d.foo; }).sortKeys(d3.descending)
+          .entries([{foo: 1}, {foo: 1}, {foo: 2}])
+          .map(function(d) { return d.key; });
+      assert.deepEqual(keys, ["2", "1"]);
+    },
+    "values can be sorted using an optional comparator": function(nest) {
+      var entries = nest()
+          .key(function(d) { return d.foo; })
+          .sortValues(function(a, b) { return a.bar - b.bar; })
+          .entries([{foo: 1, bar: 2}, {foo: 1, bar: 0}, {foo: 1, bar: 1}, {foo: 2}]);
+      assert.deepEqual(entries, [
+        {key: "1", values: [{foo: 1, bar: 0}, {foo: 1, bar: 1}, {foo: 1, bar: 2}]},
+        {key: "2", values: [{foo: 2}]}
+      ]);
+    },
+    "values can be aggregated using an optional rollup": function(nest) {
+      var entries = nest()
+          .key(function(d) { return d.foo; })
+          .rollup(function(values) { return d3.sum(values, function(d) { return d.bar; }); })
+          .entries([{foo: 1, bar: 2}, {foo: 1, bar: 0}, {foo: 1, bar: 1}, {foo: 2}]);
+      assert.deepEqual(entries, [
+        {key: "1", values: 3},
+        {key: "2", values: 0}
+      ]);
+    },
+    "multiple key functions can be specified": function(nest) {
+      var entries = nest()
+          .key(function(d) { return d[0]; }).sortKeys(d3.ascending)
+          .key(function(d) { return d[1]; }).sortKeys(d3.ascending)
+          .entries([[0, 1], [0, 2], [1, 1], [1, 2], [0, 2]]);
+      assert.deepEqual(entries, [
+        {key: "0", values: [
+          {key: "1", values: [[0, 1]]},
+          {key: "2", values: [[0, 2], [0, 2]]}
+        ]},
+        {key: "1", values: [
+          {key: "1", values: [[1, 1]]},
+          {key: "2", values: [[1, 2]]}
+        ]}
+      ]);
+    },
+    "the rollup function only applies to leaf values": function(nest) {
+      var entries = nest()
+          .key(function(d) { return d[0]; }).sortKeys(d3.ascending)
+          .key(function(d) { return d[1]; }).sortKeys(d3.ascending)
+          .rollup(function(values) { return values.length; })
+          .entries([[0, 1], [0, 2], [1, 1], [1, 2], [0, 2]]);
+      assert.deepEqual(entries, [
+        {key: "0", values: [
+          {key: "1", values: 1},
+          {key: "2", values: 2}
+        ]},
+        {key: "1", values: [
+          {key: "1", values: 1},
+          {key: "2", values: 1}
+        ]}
+      ]);
+    },
+    "the value comparator only applies to leaf values": function(nest) {
+      var entries = nest()
+          .key(function(d) { return d[0]; }).sortKeys(d3.ascending)
+          .key(function(d) { return d[1]; }).sortKeys(d3.ascending)
+          .sortValues(function(a, b) { return a[2] - b[2]; })
+          .entries([[0, 1], [0, 2, 1], [1, 1], [1, 2], [0, 2, 0]]);
+      assert.deepEqual(entries, [
+        {key: "0", values: [
+          {key: "1", values: [[0, 1]]},
+          {key: "2", values: [[0, 2, 0], [0, 2, 1]]}
+        ]},
+        {key: "1", values: [
+          {key: "1", values: [[1, 1]]},
+          {key: "2", values: [[1, 2]]}
+        ]}
+      ]);
+    },
+    "the key comparator only applies to the last-specified key": function(nest) {
+      var entries = nest()
+          .key(function(d) { return d[0]; }).sortKeys(d3.ascending)
+          .key(function(d) { return d[1]; }).sortKeys(d3.descending)
+          .entries([[0, 1], [0, 2], [1, 1], [1, 2], [0, 2]]);
+      assert.deepEqual(entries, [
+        {key: "0", values: [
+          {key: "2", values: [[0, 2], [0, 2]]},
+          {key: "1", values: [[0, 1]]}
+        ]},
+        {key: "1", values: [
+          {key: "2", values: [[1, 2]]},
+          {key: "1", values: [[1, 1]]}
+        ]}
+      ]);
+      var entries = nest()
+          .key(function(d) { return d[0]; }).sortKeys(d3.descending)
+          .key(function(d) { return d[1]; }).sortKeys(d3.ascending)
+          .entries([[0, 1], [0, 2], [1, 1], [1, 2], [0, 2]]);
+      assert.deepEqual(entries, [
+        {key: "1", values: [
+          {key: "1", values: [[1, 1]]},
+          {key: "2", values: [[1, 2]]}
+        ]},
+        {key: "0", values: [
+          {key: "1", values: [[0, 1]]},
+          {key: "2", values: [[0, 2], [0, 2]]}
+        ]}
+      ]);
+    },
+    "if no keys are specified, the input array is returned": function(nest) {
+      var array = [new Object()];
+      assert.strictEqual(nest().entries(array), array);
+    }
+  }
+});
+
+suite.addBatch({
+  "map": {
+    topic: function() {
+      return d3.nest;
+    },
+    "returns a map of each distinct key": function(nest) {
+      var map = nest()
+          .key(function(d) { return d.foo; })
+          .map([{foo: 1, bar: 0}, {foo: 2}, {foo: 1, bar: 1}]);
+      assert.deepEqual(map, {
+        "1": [{foo: 1, bar: 0}, {foo: 1, bar: 1}],
+        "2": [{foo: 2}]
+      });
+    },
+    "values can be sorted using an optional comparator": function(nest) {
+      var map = nest()
+          .key(function(d) { return d.foo; })
+          .sortValues(function(a, b) { return a.bar - b.bar; })
+          .map([{foo: 1, bar: 2}, {foo: 1, bar: 0}, {foo: 1, bar: 1}, {foo: 2}]);
+      assert.deepEqual(map, {
+        "1": [{foo: 1, bar: 0}, {foo: 1, bar: 1}, {foo: 1, bar: 2}],
+        "2": [{foo: 2}]
+      });
+    },
+    "values can be aggregated using an optional rollup": function(nest) {
+      var map = nest()
+          .key(function(d) { return d.foo; })
+          .rollup(function(values) { return d3.sum(values, function(d) { return d.bar; }); })
+          .map([{foo: 1, bar: 2}, {foo: 1, bar: 0}, {foo: 1, bar: 1}, {foo: 2}]);
+      assert.deepEqual(map, {
+        "1": 3,
+        "2": 0
+      });
+    },
+    "multiple key functions can be specified": function(nest) {
+      var map = nest()
+          .key(function(d) { return d[0]; }).sortKeys(d3.ascending)
+          .key(function(d) { return d[1]; }).sortKeys(d3.ascending)
+          .map([[0, 1], [0, 2], [1, 1], [1, 2], [0, 2]]);
+      assert.deepEqual(map, {
+        "0": {
+          "1": [[0, 1]],
+          "2": [[0, 2], [0, 2]]
+        },
+        "1": {
+          "1": [[1, 1]],
+          "2": [[1, 2]]
+        }
+      });
+    },
+    "the rollup function only applies to leaf values": function(nest) {
+      var map = nest()
+          .key(function(d) { return d[0]; }).sortKeys(d3.ascending)
+          .key(function(d) { return d[1]; }).sortKeys(d3.ascending)
+          .rollup(function(values) { return values.length; })
+          .map([[0, 1], [0, 2], [1, 1], [1, 2], [0, 2]]);
+      assert.deepEqual(map, {
+        "0": {
+          "1": 1,
+          "2": 2
+        },
+        "1": {
+          "1": 1,
+          "2": 1
+        }
+      });
+    },
+    "the value comparator only applies to leaf values": function(nest) {
+      var map = nest()
+          .key(function(d) { return d[0]; }).sortKeys(d3.ascending)
+          .key(function(d) { return d[1]; }).sortKeys(d3.ascending)
+          .sortValues(function(a, b) { return a[2] - b[2]; })
+          .map([[0, 1], [0, 2, 1], [1, 1], [1, 2], [0, 2, 0]]);
+      assert.deepEqual(map, {
+        "0": {
+          "1": [[0, 1]],
+          "2": [[0, 2, 0], [0, 2, 1]]
+        },
+        "1": {
+          "1": [[1, 1]],
+          "2": [[1, 2]]
+        }
+      });
+    },
+    "if no keys are specified, the input array is returned": function(nest) {
+      var array = [new Object()];
+      assert.strictEqual(nest().map(array), array);
+    }
+  }
+});
+
+suite.export(module);