added unit test for exceptions

[stanleyhlng]

This PR adds unit test for exception to increase overall code coverage from 87% to 92%.

➜  mocha-multi-reporters git:(exception-unit-test)  npm run test 

> mocha-multi-reporters@1.1.1 test /Users/stanleyn/Projects/stanleyhlng/github.com/mocha-multi-reporters
> JENKINS_MOCHA_COVERAGE=true jenkins-mocha --timeout 5000 tests/**/*.test.js*



  lib/MultiReporters
    #static
      #CONFIG_FILE
        ✓ equals to "../config.json"
    #instance
      #internal
        #options (reporters - single)
          ✓ return reporter options: "dot"
          ✓ return reporter options: "xunit"
        #options (reporters - multiple)
          ✓ return default options
          ✓ return custom options
          ✓ return resultant options by merging both default and custom options
      #external
        #options (external reporters - single)
          ✓ return reporter options: "dot"
      #exception
Error: JSON.parse error!
    at Context.<anonymous> (/Users/stanleyn/Projects/stanleyhlng/github.com/mocha-multi-reporters/tests/lib/MultiReporters.test.js:141:23)
    at callFn (/Users/stanleyn/Projects/stanleyhlng/github.com/mocha-multi-reporters/node_modules/jenkins-mocha/node_modules/mocha/lib/runnable.js:326:21)
    at Hook.Runnable.run (/Users/stanleyn/Projects/stanleyhlng/github.com/mocha-multi-reporters/node_modules/jenkins-mocha/node_modules/mocha/lib/runnable.js:319:7)
    at next (/Users/stanleyn/Projects/stanleyhlng/github.com/mocha-multi-reporters/node_modules/jenkins-mocha/node_modules/mocha/lib/runner.js:298:10)
    at Immediate.<anonymous> (/Users/stanleyn/Projects/stanleyhlng/github.com/mocha-multi-reporters/node_modules/jenkins-mocha/node_modules/mocha/lib/runner.js:320:5)
    at runCallback (timers.js:637:20)
    at tryOnImmediate (timers.js:610:5)
    at processImmediate [as _immediateCallback] (timers.js:582:5)
        ✓ throw an exception in default options
Error: JSON.parse error!
    at Context.<anonymous> (/Users/stanleyn/Projects/stanleyhlng/github.com/mocha-multi-reporters/tests/lib/MultiReporters.test.js:141:23)
    at callFn (/Users/stanleyn/Projects/stanleyhlng/github.com/mocha-multi-reporters/node_modules/jenkins-mocha/node_modules/mocha/lib/runnable.js:326:21)
    at Hook.Runnable.run (/Users/stanleyn/Projects/stanleyhlng/github.com/mocha-multi-reporters/node_modules/jenkins-mocha/node_modules/mocha/lib/runnable.js:319:7)
    at next (/Users/stanleyn/Projects/stanleyhlng/github.com/mocha-multi-reporters/node_modules/jenkins-mocha/node_modules/mocha/lib/runner.js:298:10)
    at Immediate.<anonymous> (/Users/stanleyn/Projects/stanleyhlng/github.com/mocha-multi-reporters/node_modules/jenkins-mocha/node_modules/mocha/lib/runner.js:320:5)
    at runCallback (timers.js:637:20)
    at tryOnImmediate (timers.js:610:5)
    at processImmediate [as _immediateCallback] (timers.js:582:5)
        ✓ throw an exception in custom options
    #test

#multi-reporter
  ✓ #test-1
  1) #test-2

  1 passing (6ms)
  1 failing

  1) #multi-reporter #test-2:

  Error
      at Context.<anonymous> (tests/lib/MultiReporters.test.js:196:30)



      ✓ should have 1 test failure

#multi-reporter
  - #test-1
  - #test-2

  0 passing (1ms)
  2 pending

      ✓ should have 1 test pending


  11 passing (191ms)

=============================================================================
Writing coverage object [/Users/stanleyn/Projects/stanleyhlng/github.com/mocha-multi-reporters/artifacts/coverage/coverage.json]
Writing coverage reports at [/Users/stanleyn/Projects/stanleyhlng/github.com/mocha-multi-reporters/artifacts/coverage]
=============================================================================

=============================== Coverage summary ===============================
Statements   : 92.65% ( 63/68 )
Branches     : 60% ( 6/10 )
Functions    : 100% ( 6/6 )
Lines        : 92.65% ( 63/68 )
================================================================================

[coveralls]

Coverage increased (+5.9%) to 92.647% when pulling 98e2406 on exception-unit-test into 925f61f on master.

[stanleyhlng]

published mocha-multi-reporters@1.1.2