atom/test/subscribe.js

shared, synchronous, independent state for javascript apps

"use strict";

var atom = require("../");
var test = require("tape");

var initialState = 0;
var genericAction = { a: 1 };
var returnTrue = function () {
  return true;
};

test("subscribed listener should be called", function (t) {
  t.plan(1);

  var called = false;
  var store = atom(returnTrue, initialState);

  store.subscribe(function () {
    called = true;
  });

  store.dispatch(genericAction);

  t.ok(called);
});

test("subscribed listener should get updated state", function (t) {
  t.plan(1);

  var store = atom(returnTrue, initialState);

  store.subscribe(function () {
    t.notEqual(initialState, store.getState());
  });

  store.dispatch(genericAction);
});

test("subscribe should throw when listener not a function", function (t) {
  t.plan(1);

  var thrown = false;
  var store = atom(returnTrue, initialState);

  try {
    store.subscribe({});
  } catch (e) {
    thrown = true;
  }

  t.ok(thrown);
});