var test = require('tape') var isFunction = require('./index.js') test('isFunction', function (t) { t.ok(!isFunction(), 'undefined is not a function') t.ok(!isFunction(null), 'null is not a function') t.ok(!isFunction(''), 'string is not a function') t.ok(!isFunction(/a/), 'regex is not a function') t.ok(!isFunction(true), 'true is not a function') t.ok(!isFunction(false), 'false is not a function') t.ok(!isFunction(NaN), 'NaN is not a function') t.ok(!isFunction(42), '42 is not a function') t.ok(isFunction(function () {}), 'function is a function') t.ok(isFunction(setTimeout), 'setTimeout is a function') t.end() }) if (typeof window !== 'undefined') { test('browser quirks', function (t) { t.plan(2) t.ok(isFunction(window.alert), 'alert is a function') window.testRegExpFromIframe = function (regexp) { t.ok(!isFunction(regexp)) } var iframe = document.createElement('iframe') document.body.appendChild(iframe) iframe.contentWindow.document.write([ "" ].join("\n")); }) }