cylon-i2c/spec/lib/hmc6352.spec.js

Cylon.js drivers for i2c devices

"use strict";

var Hmc6352 = lib("hmc6352");

describe("Cylon.Drivers.I2C.Hmc6352", function() {
  var driver;

  beforeEach(function() {
    driver = new Hmc6352({
      name: "compass",
      connection: {}
    });
  });

  describe("#constructor", function() {
    it("sets @address to 0x21 by default", function() {
      expect(driver.address).to.be.eql(0x21);
    });
  });

  describe("#commands", function() {
    it("is an object containing Hmc6352 commands", function() {
      for (var c in driver.commands) {
        expect(driver.commands[c]).to.be.a("function");
      }
    });
  });

  describe("#heading", function() {
    var callback;

    beforeEach(function() {
      callback = spy();
      driver.connection.i2cRead = stub().callsArgWith(3, null, [30, 20]);
      stub(driver, "parseHeading").returns(20);
      driver.heading(callback);
    });

    afterEach(function() {
      driver.connection.i2cRead = undefined;
      driver.parseHeading.restore();
    });

    it("calls the callback with the results of parseHeading", function() {
      expect(driver.parseHeading).to.be.calledWith([30, 20]);
      expect(callback).to.be.calledWith(null, 20);
    });
  });

  describe("#commandBytes", function() {
    it("creates an ASCII buffer with the provided string", function() {
      var bytes = driver.commandBytes("testing");
      expect(bytes).to.be.a("object");
      expect(bytes.length).to.be.eql(7);
    });
  });

  describe("#parseHeading", function() {
    it("parses an array to determine the heading", function() {
      expect(driver.parseHeading([0, 0])).to.be.eql(0);

      expect(driver.parseHeading([0, 1800])).to.be.eql(180);
    });
  });
});