var test = require("tape") , forEach = require("..") test("forEach calls each iterator", function (t) { var count = 0 t.plan(4) forEach({ a: 1, b: 2 }, function (value, key) { if (count === 0) { t.equal(value, 1) t.equal(key, "a") } else { t.equal(value, 2) t.equal(key, "b") } count++ }) }) test("forEach calls iterator with correct this value", function (t) { var thisValue = {} t.plan(1) forEach([0], function () { t.equal(this, thisValue) }, thisValue) }) test('second argument: iterator', function (t) { var arr = [] t.throws(function () { forEach(arr) }, TypeError, 'undefined is not a function') t.throws(function () { forEach(arr, null) }, TypeError, 'null is not a function') t.throws(function () { forEach(arr, '') }, TypeError, 'string is not a function') t.throws(function () { forEach(arr, /a/) }, TypeError, 'regex is not a function') t.throws(function () { forEach(arr, true) }, TypeError, 'true is not a function') t.throws(function () { forEach(arr, false) }, TypeError, 'false is not a function') t.throws(function () { forEach(arr, NaN) }, TypeError, 'NaN is not a function') t.throws(function () { forEach(arr, 42) }, TypeError, '42 is not a function') t.doesNotThrow(function () { forEach(arr, function () {}) }, 'function is a function') t.doesNotThrow(function () { forEach(arr, setTimeout) }, 'setTimeout is a function') if (typeof window !== 'undefined') { t.doesNotThrow(function () { forEach(arr, window.alert) }, 'alert is a function') } t.end() }) test('array', function (t) { var arr = [1, 2, 3] t.test('iterates over every item', function (st) { var index = 0 forEach(arr, function () { index += 1 }) st.equal(index, arr.length, 'iterates ' + arr.length + ' times') st.end() }) t.test('first iterator argument', function (st) { var index = 0 st.plan(arr.length) forEach(arr, function (item) { st.equal(arr[index], item, 'item ' + index + ' is passed as first argument') index += 1 }) st.end(); }) t.test('second iterator argument', function (st) { var counter = 0 st.plan(arr.length) forEach(arr, function (item, index) { st.equal(counter, index, 'index ' + index + ' is passed as second argument') counter += 1 }) st.end(); }) t.test('third iterator argument', function (st) { st.plan(arr.length) forEach(arr, function (item, index, array) { st.deepEqual(arr, array, 'array is passed as third argument') }) st.end(); }) t.test('context argument', function (st) { var context = {} forEach([], function () { st.equal(this, context, '"this" is the passed context') }, context) st.end() }) t.end() }) test('object', function (t) { var obj = { a: 1, b: 2, c: 3 } var keys = ['a', 'b', 'c'] var F = function () { this.a = 1 this.b = 2 } F.prototype.c = 3 var fKeys = ['a', 'b'] t.test('iterates over every object literal key', function (st) { var counter = 0 forEach(obj, function () { counter += 1 }) st.equal(counter, keys.length, 'iterated ' + counter + ' times') st.end() }) t.test('iterates only over own keys', function (st) { var counter = 0 forEach(new F(), function () { counter += 1 }) st.equal(counter, fKeys.length, 'iterated ' + fKeys.length + ' times') st.end() }) t.test('first iterator argument', function (st) { var index = 0 st.plan(keys.length) forEach(obj, function (item) { st.equal(obj[keys[index]], item, 'item at key ' + keys[index] + ' is passed as first argument') index += 1 }) st.end() }) t.test('second iterator argument', function (st) { var counter = 0 st.plan(keys.length) forEach(obj, function (item, key) { st.equal(keys[counter], key, 'key ' + key + ' is passed as second argument') counter += 1 }) st.end() }) t.test('third iterator argument', function (st) { st.plan(keys.length) forEach(obj, function (item, key, object) { st.deepEqual(obj, object, 'object is passed as third argument') }) st.end() }) t.test('context argument', function (st) { var context = {} forEach({}, function () { st.equal(this, context, '"this" is the passed context') }, context) st.end() }) t.end() }) test('string', function (t) { var str = 'str' t.test('second iterator argument', function (st) { var counter = 0 st.plan(str.length * 2 + 1) forEach(str, function (item, index) { st.equal(counter, index, 'index ' + index + ' is passed as second argument') st.equal(str.charAt(index), item) counter += 1 }) st.equal(counter, str.length, 'iterates ' + str.length + ' times') st.end() }) t.end() })