Question

How do you test your getters?

Answer 1

It is easier to test getters similar to mutations. It is recommended to test these getters if they have complicated computation.

Let's take a simple todo filter as a getter

// getters.js
export const getters = {
  filterTodos (state, status) {
    return state.todos.filter(todo => {
      return todo.status === status
    })
  }
}

And the test case for above getter as follows,

// getters.spec.js
import { expect } from 'chai'
import { getters } from './getters'

describe('getters', () => {
  it('filteredTodos', () => {
    // mock state
    const state = {
      todos: [
        { id: 1, title: 'design', status: 'Completed' },
        { id: 2, title: 'testing', status: 'InProgress' },
        { id: 3, title: 'development', status: 'Completed' }
      ]
    }
    // mock getter
    const filterStatus = 'Completed'

    // get the result from the getter
    const result = getters.filterTodos(state, filterStatus)

    // assert the result
    expect(result).to.deep.equal([
      { id: 1, title: 'design', status: 'Completed' },
      { id: 2, title: 'development', status: 'Completed' }
    ])
  })
})