require("../env");

require("../../d3");

var vows = require("vows"),

    assert = require("assert");

var suite = vows.describe("selection.node");

suite.addBatch({

  "select(body)": {

    topic: function() {

      return d3.select("body").html("");

    },

    "returns null for empty selections": function(body) {

      assert.isNull(body.select("foo").node());

    },

    "returns the first element for non-empty selections": function(body) {

      assert.isTrue(body.node() === document.body);

    },

    "ignores null nodes": function(body) {

      var some = d3.select("body");

      some[0][0] = null;

      assert.isNull(some.node());

    }

  }

});

suite.addBatch({

  "selectAll(div)": {

    topic: function() {

      var body = d3.select("body").html("");

      body.append("div").append("span");

      body.append("div");

      return body.selectAll("div");

    },

    "returns null for empty selections": function(div) {

      assert.isNull(div.select("foo").node());

    },

    "returns the first element for non-empty selections": function(div) {

      assert.isTrue(div.node() === div[0][0]);

    },

    "ignores null nodes": function(div) {

      var some = d3.selectAll("div");

      some[0][0] = null;

      assert.isTrue(some.node() === div[0][1]);

    }

  }

});

suite.export(module);