var vows = require(“vows”),
_ = require("../../"), load = require("../load"), assert = require("../assert");
var suite = vows.describe(“d3.scale.category”);
suite.addBatch({
"category": { topic: load("scale/category").expression("d3.scale"), "category10": category("category10", 10), "category20": category("category20", 20), "category20b": category("category20b", 20), "category20c": category("category20c", 20) }
});
function category(category, n) {
return { "is an ordinal scale": function(scale) { var x = scale[category](), colors = x.range(); assert.lengthOf(x.domain(), 0); assert.lengthOf(x.range(), n); assert.equal(x(1), colors[0]); assert.equal(x(2), colors[1]); assert.equal(x(1), colors[0]); var y = x.copy(); assert.deepEqual(y.domain(), x.domain()); assert.deepEqual(y.range(), x.range()); x.domain(_.range(n)); for (var i = 0; i < n; ++i) assert.equal(x(i + n), x(i)); assert.equal(y(1), colors[0]); assert.equal(y(2), colors[1]); }, "each instance is isolated": function(scale) { var a = scale[category](), b = scale[category](), colors = a.range(); assert.equal(a(1), colors[0]); assert.equal(b(2), colors[0]); assert.equal(b(1), colors[1]); assert.equal(a(1), colors[0]); }, "contains the expected number of values in the range": function(scale) { var x = scale[category](); assert.lengthOf(x.range(), n); }, "each range value is distinct": function(scale) { var map = {}, count = 0, x = scale[category](); x.range().forEach(function(v) { if (!(v in map)) { map[v] = ++count; } }); assert.equal(count, x.range().length); }, "each range value is a hexadecimal color": function(scale) { var x = scale[category](); x.range().forEach(function(v) { assert.match(v, /#[0-9a-f]{6}/); v = _.rgb(v); assert.isFalse(isNaN(v.r)); assert.isFalse(isNaN(v.g)); assert.isFalse(isNaN(v.b)); }); }, "no range values are very dark or very light": function(scale) { var x = scale[category](); x.range().forEach(function(v) { var c = _.hsl(v); assert.isTrue(c.l >= .34, "expected " + v + " to be lighter (l = " + c.l + ")"); assert.isTrue(c.l <= .89, "expected " + v + " to be darker (l = " + c.l + ")"); }); } };
}
suite.export(module);