documentit/node_modules/object-keys/test/foreach.js

var test = require('tape');
var forEach = require('../foreach.js');

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 = {};
		st.plan(arr.length);
		forEach(arr, 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 = {};
		st.plan(1);
		forEach({foo: 'bar'}, 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');
	});
	t.end();
});