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

'use strict';

/* globals window */

var test = require('tape');

var generatorFuncs = require('make-generator-function')();
var hasToStringTag = require('has-tostringtag/shams')();
var forEach = require('for-each');

var isGeneratorFunction = require('../index');

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(isGeneratorFunction(nonFunc), nonFunc + ' is not a function');
        });
        t.end();
});

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

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

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

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

test('returns false for non-generator 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(isGeneratorFunction(func), 'anonymous function with faked toString is not a generator function');
        t.end();
});

test('returns false for non-generator function with faked @@toStringTag', { skip: !hasToStringTag || generatorFuncs.length === 0 }, function (t) {
        var generatorFunc = generatorFuncs[0];
        /** @type {{ toString(): unknown; valueOf(): unknown; [Symbol.toStringTag]?: unknown; }} */
        var fakeGenFunction = {
                toString: function () { return String(generatorFunc); },
                valueOf: function () { return generatorFunc; }
        };
        fakeGenFunction[Symbol.toStringTag] = 'GeneratorFunction';
        t.notOk(isGeneratorFunction(fakeGenFunction), 'fake GeneratorFunction with @@toStringTag "GeneratorFunction" is not a generator function');
        t.end();
});

test('returns true for generator functions', function (t) {
        if (generatorFuncs.length > 0) {
                forEach(generatorFuncs, function (generatorFunc) {
                        t.ok(isGeneratorFunction(generatorFunc), generatorFunc + ' is generator function');
                });
        } else {
                t.skip('generator function is generator function - this environment does not support ES6 generator functions. Please run `node --harmony`, or use a supporting browser.');
        }
        t.end();
});