var vows = require("vows"),

load = require("../load"),

assert = require("../assert");

var suite = vows.describe("d3.scale.threshold");

suite.addBatch({

"threshold": {

topic: load("scale/threshold").expression("d3.scale.threshold"),

"has the default domain [.5]": function(threshold) {

var x = threshold();

assert.deepEqual(x.domain(), [.5]);

assert.equal(x(.49), 0);

},

"has the default range [0, 1]": function(threshold) {

var x = threshold();

assert.deepEqual(x.range(), [0, 1]);

assert.equal(x(.50), 1);

},

"maps a number to a discrete value in the range": function(threshold) {

var x = threshold().domain([1/3, 2/3]).range(["a", "b", "c"]);

assert.equal(x(0), "a");

assert.equal(x(.2), "a");

assert.equal(x(.4), "b");

assert.equal(x(.6), "b");

assert.equal(x(.8), "c");

assert.equal(x(1), "c");

},

"returns undefined if the specified value is not orderable": function(threshold) {

var x = threshold().domain([1/3, 2/3]).range(["a", "b", "c"]);

assert.isUndefined(x());

assert.isUndefined(x(undefined));

assert.isUndefined(x(NaN));

assert.equal(x(null), "a"); // null < 1/3

},

"domain values are arbitrary": function(threshold) {

var x = threshold().domain(["10", "2"]).range([0, 1, 2]);

assert.strictEqual(x.domain()[0], "10");

assert.strictEqual(x.domain()[1], "2");

assert.equal(x("0"), 0);

assert.equal(x("12"), 1);

assert.equal(x("3"), 2);

},

"range values are arbitrary": function(threshold) {

var a = {}, b = {}, c = {}, x = threshold().domain([1/3, 2/3]).range([a, b, c]);

assert.equal(x(0), a);

assert.equal(x(.2), a);

assert.equal(x(.4), b);

assert.equal(x(.6), b);

assert.equal(x(.8), c);

assert.equal(x(1), c);

},

"invertExtent": {

"returns the domain extent for the specified range value": function(threshold) {

var a = {}, b = {}, c = {}, x = threshold().domain([1/3, 2/3]).range([a, b, c]);

assert.deepEqual(x.invertExtent(a), [undefined, 1/3]);

assert.deepEqual(x.invertExtent(b), [1/3, 2/3]);

assert.deepEqual(x.invertExtent(c), [2/3, undefined]);

}

}

}

});

suite.export(module);