combineFilters.spec.js

import { expect, describe, it } from 'vitest'
import { combineFilters } from '../src/index'

describe('Combine Filters', () => {
  const sample = {
    action: { type: 'TEST' },
    currentState: 1,
    previousHistory: [0, -1]
  }

  function checkArguments (action, currentState, previousHistory) {
    return (
      action === sample.action &&
      currentState === sample.currentState &&
      previousHistory === sample.previousHistory
    )
  }

  function checkArgumentsNot (action, currentState, previousHistory) {
    return (
      action !== sample.action ||
      currentState !== sample.currentState ||
      previousHistory !== sample.previousHistory
    )
  }

  function checkStateNot1 (action, state) { return state !== 1 }
  function checkStateNot2 (action, state) { return state !== 2 }

  function checkIfCalled (action) {
    action.hasBeenCalled = true
    return true
  }

  it('should pass its arguments while calling a filter', () => {
    expect(combineFilters(checkArguments, checkArguments)(sample.action, sample.currentState, sample.previousHistory))
      .to.equal(true)
    expect(combineFilters(checkArgumentsNot, checkArguments)(sample.action, sample.currentState, sample.previousHistory))
      .to.equal(false)
  })

  it('should return false if any filter does', () => {
    expect(combineFilters(checkStateNot1, checkStateNot2)(null, 1)).to.equal(false)
    expect(combineFilters(checkStateNot1, checkStateNot2)(null, 2)).to.equal(false)
  })

  it('should return true if every filter does', () => {
    expect(combineFilters(checkStateNot1, checkStateNot2)(null, 3)).to.equal(true)
  })

  it('should not call remaining filters if one already returned false', () => {
    const act = { hasBeenCalled: false }
    const combined = combineFilters(checkStateNot1, checkStateNot2, checkIfCalled)

    combined(act, 2)
    expect(act.hasBeenCalled).to.equal(false)
    combined(act, 3)
    expect(act.hasBeenCalled).to.equal(true)
  })
})