message: Make use of variables in direction.test
diff: @@ -6,50 +6,55 @@ const negativeDirection = -1
  const noDirection = 0
  describe('Direction', () => {
  - describe('Converts a number', () => {
  - test('That is positive to 1', () => {
  + describe('Sets its given initial value that is', () => {
  + test('Positive to 1', () => {
  const initialValue = 10
  const direction = Direction(initialValue).get()
  expect(direction).toBe(positiveDirection)
  })
  - test('That is negative to -1', () => {
  + test('Negative to -1', () => {
  const initialValue = -10
  const direction = Direction(initialValue).get()
  expect(direction).toBe(negativeDirection)
  })
  - test('That is -0 to 0', () => {
  - const initialValue = -0
  - const direction = Direction(initialValue).get()
  + test('0 to 0', () => {
  + const direction = Direction(noDirection).get()
  expect(direction).toBe(noDirection)
  })
  - test('That is 0 to 0', () => {
  - const initialValue = 0
  - const direction = Direction(initialValue).get()
  + test('-0 to 0', () => {
  + const direction = Direction(-noDirection).get()
  expect(direction).toBe(noDirection)
  })
  })
  - describe('Converts a vector', () => {
  - test('That is positive to 1', () => {
  - const direction = Direction(0)
  + describe('Sets direction to', () => {
  + test('1 when given vector is positive', () => {
  + const direction = Direction(noDirection)
  const vector = Vector1D(10)
  direction.set(vector)
  expect(direction.get()).toBe(positiveDirection)
  })
  - test('That is negative to -1', () => {
  - const direction = Direction(0)
  + test('-1 when given vector is negative', () => {
  + const direction = Direction(noDirection)
  const vector = Vector1D(-10)
  direction.set(vector)
  expect(direction.get()).toBe(negativeDirection)
  })
  - test('That is 0 to 0', () => {
  - const direction = Direction(1)
  - const vector = Vector1D(0)
  + test('Nothing new when given vector is 0', () => {
  + const direction = Direction(positiveDirection)
  + const vector = Vector1D(noDirection)
  + direction.set(vector)
  + expect(direction.get()).toBe(positiveDirection)
  + })
  +
  + test('Nothing new when given vector is -0', () => {
  + const direction = Direction(positiveDirection)
  + const vector = Vector1D(-noDirection)
  direction.set(vector)
  expect(direction.get()).toBe(positiveDirection)
  })
  