source: imaps-frontend/node_modules/is-async-function/test/index.js@ 79a0317

'use strict';

/* globals window */

var test = require('tape');
var isAsyncFunction = require('../index');
var generatorFuncs = require('make-generator-function')();
var asyncFuncs = require('make-async-function').list();
var hasToStringTag = require('has-tostringtag/shams')();

var forEach = require('for-each');

test('returns false for non-functions', function (t) {
        var nonFuncs = [
                true,
                false,
                null,
                undefined,
                {},
                [],
                /a/g,
                'string',
                42,
                new Date()
        ];
        t.plan(nonFuncs.length);
        forEach(nonFuncs, function (nonFunc) {
                t.notOk(isAsyncFunction(nonFunc), nonFunc + ' is not a function');
        });
        t.end();
});

test('returns false for non-async functions', function (t) {
        var func = function () {};
        t.notOk(isAsyncFunction(func), 'anonymous function is not an async function');

        var namedFunc = function foo() {};
        t.notOk(isAsyncFunction(namedFunc), 'named function is not an async function');

        if (typeof window === 'undefined') {
                t.skip('window.alert is not an async function');
        } else {
                t.notOk(isAsyncFunction(window.alert), 'window.alert is not an async function');
        }
        t.end();
});

var fakeToString = function () { return 'async function () { return "TOTALLY REAL I SWEAR!"; }'; };

test('returns false for non-async function with faked toString', function (t) {
        var func = function () {};
        func.toString = fakeToString;

        t.notEqual(String(func), Function.prototype.toString.apply(func), 'faked toString is not real toString');
        t.notOk(isAsyncFunction(func), 'anonymous function with faked toString is not an async function');
        t.end();
});

test('returns false for generator functions', function (t) {
        if (generatorFuncs.length > 0) {
                forEach(generatorFuncs, function (generatorFunc) {
                        t.notOk(isAsyncFunction(generatorFunc), generatorFunc + ' is not async function');
                });
        } else {
                t.skip('generator function is not async function - this environment does not support ES6 generator functions. Please use an engine that supports them.');
        }
        t.end();
});

test('returns false for non-async function with faked @@toStringTag', { skip: !hasToStringTag || asyncFuncs.length === 0 }, function (t) {
        var asyncFunc = asyncFuncs[0];
        /** @type {{ toString(): unknown; valueOf(): unknown; [Symbol.toStringTag]?: unknown }} */
        var fakeAsyncFunction = {
                toString: function () { return String(asyncFunc); },
                valueOf: function () { return asyncFunc; }
        };
        fakeAsyncFunction[Symbol.toStringTag] = 'AsyncFunction';
        t.notOk(isAsyncFunction(fakeAsyncFunction), 'fake AsyncFunction with @@toStringTag "AsyncFunction" is not an async function');
        t.end();
});

test('returns true for async functions', function (t) {
        if (asyncFuncs.length > 0) {
                forEach(asyncFuncs, function (asyncFunc) {
                        t.ok(isAsyncFunction(asyncFunc), asyncFunc + ' is async function');
                });
        } else {
                t.skip('async function is async function - this environment does not support ES2018 async functions. Please use an engine that supports them.');
        }
        t.end();
});