actions.spec.js

import actions from "@/store/actions.js"

let url = ''
let body = {}
let mockError = false

jest.mock("axios", () => ({
  post: (_url, _body) => { 
    return new Promise((resolve) => {
      if (mockError) 
        throw Error("Mock error")

      url = _url
      body = _body
      resolve(true)
    })
  }
}))


describe("authenticate", () => {
  it("authenticated a user", async () => {
    const commit = jest.fn()
    const username = "alice"
    const password = "password"

    await actions.authenticate({ commit }, { username, password })

    expect(url).toBe("/api/authenticate")
    expect(body).toEqual({ username, password })
    expect(commit).toHaveBeenCalledWith(
      "SET_AUTHENTICATED", true)
  })

  it("catches an error", async () => {
    mockError = true

    await expect(actions.authenticate({ commit: jest.fn() }, {}))
      .rejects.toThrow("API Error occurred.")
  })
})