gob/spec/gob.coffee

gob (aka G.O.B) magically vanishes lines from your output streams.

Gob = require '../dist/index.js'

expect = require('chai').expect
sinon = require 'sinon'

describe 'Gob', ->
  describe 'when given an output stream', ->
    output = undefined
    gob = undefined
    result = undefined

    before ->
      output = {
        write: (str) -> result = str
        columns: 10
      }
      gob = Gob.gob(output)

    describe 'when writing to the output stream', ->
      describe 'when the lines written does not wrap the console', ->
        before ->
          result = ''
          gob.set()
          output.write '\n\n\n\n'
          output.write ''
          output.write '\n'

        it 'keeps track of the number of newlines written', ->
          expect(gob._lines()).to.eq 5

      describe 'when the lines written does wraps the console', ->
        before ->
          gob.set()
          output.write 'longer than 10 characters'

        it 'breaks the wrap and keeps track of the number of newlines written', ->
          expect(gob._lines()).to.eq 2

    describe 'set', ->
      before ->
        output.write '\n\n\n\n'
        gob.set()

      it 'sets the number of lines to 0', ->
        expect(gob._lines()).to.eq 0

    describe 'vanish', ->
      clearScreen = undefined
      before ->
        output.write '\n\n\n\n'
        gob.vanish()

      it 'moves the cursor back', ->
        expect(Gob.moveCursorX).to.eq 0
        expect(Gob.moveCursorY).to.eq -4

      it 'clears the screen down', ->
        expect(Gob.clearScreenDownCalled).to.eq true

  describe 'when NOT given an output stream', ->
    it 'throws an error when NOT given an output stream', ->
      expect(-> Gob.gob()).to.throw('gob requires an output stream.')