mathjs/test/expression/node/RangeNode.test.js

// test RangeNode
var assert = require('assert'),
    approx = require('../../../tools/approx'),
    mathjs = require('../../../index'),
    math = mathjs(),
    Node = require('../../../lib/expression/node/Node'),
    ConstantNode = require('../../../lib/expression/node/ConstantNode'),
    SymbolNode = require('../../../lib/expression/node/SymbolNode'),
    RangeNode = require('../../../lib/expression/node/RangeNode');

describe('RangeNode', function() {

  it ('should create a RangeNode', function () {
    var start = new ConstantNode('number', '0');
    var end = new ConstantNode('number', '10');
    var n = new RangeNode([start, end]);
    assert(n instanceof RangeNode);
    assert(n instanceof Node);
    assert.equal(n.type, 'RangeNode');
  });

  it ('should throw an error when calling without new operator', function () {
    var start = new ConstantNode('number', '0');
    var end = new ConstantNode('number', '10');
    assert.throws(function () {RangeNode([start, end])}, SyntaxError);
  });

  it ('should throw an error creating a RangeNode with wrong number or type of arguments', function () {
    var start = new ConstantNode('number', '0');
    var end = new ConstantNode('number', '10');

    assert.throws(function () { new RangeNode(); }, TypeError);
    assert.throws(function () { new RangeNode(start, end); }, TypeError);
    assert.throws(function () { new RangeNode([]); }, TypeError);
    assert.throws(function () { new RangeNode([start, end, start, end]); }, TypeError);
    assert.throws(function () { new RangeNode([0, 10]); }, TypeError);
  });

  it ('should compile a RangeNode', function () {
    var start = new ConstantNode('number', '0');
    var end = new ConstantNode('number', '10');
    var step = new ConstantNode('number', '2');
    var n = new RangeNode([start, end, step]);

    var expr = n.compile(math);
    assert.deepEqual(expr.eval(), math.matrix([0, 2, 4, 6, 8, 10]));
  });

  it ('should find a RangeNode', function () {
    var start = new ConstantNode('number', '0');
    var end = new ConstantNode('number', '10');
    var step = new ConstantNode('number', '2');
    var n = new RangeNode([start, end, step]);

    assert.deepEqual(n.find({type: RangeNode}),  [n]);
    assert.deepEqual(n.find({type: SymbolNode}),  []);
    assert.deepEqual(n.find({type: ConstantNode}),  [start, step, end]);
    assert.deepEqual(n.find({type: ConstantNode, properties: {value: '2'}}),  [step]);
    assert.deepEqual(n.find({type: ConstantNode, properties: {value: '4'}}),  []);
  });

  it ('should match a RangeNode', function () {
    var start = new ConstantNode('number', '0');
    var end = new ConstantNode('number', '10');
    var a = new RangeNode([start, end]);

    assert.equal(a.match({type: RangeNode}),  true);
    assert.equal(a.match({type: ConstantNode}), false);
  });

  it ('should stringify a RangeNode without step', function () {
    var start = new ConstantNode('number', '0');
    var end = new ConstantNode('number', '10');
    var n = new RangeNode([start, end]);

    assert.equal(n.toString(), '0:10');
  });

  it ('should stringify a RangeNode with step', function () {
    var start = new ConstantNode('number', '0');
    var end = new ConstantNode('number', '10');
    var step = new ConstantNode('number', '2');
    var n = new RangeNode([start, end, step]);

    assert.equal(n.toString(), '0:2:10');
  });

});