underscore_collections_test.go

package otto

import (
	"testing"
)

// each
func Test_underscore_collections_0(t *testing.T) {
	tt(t, func() {
		test, _ := test_()

		test(`
  test("each", function() {
    _.each([1, 2, 3], function(num, i) {
      equal(num, i + 1, 'each iterators provide value and iteration count');
    });

    var answers = [];
    _.each([1, 2, 3], function(num){ answers.push(num * this.multiplier);}, {multiplier : 5});
    equal(answers.join(', '), '5, 10, 15', 'context object property accessed');

    answers = [];
    _.forEach([1, 2, 3], function(num){ answers.push(num); });
    equal(answers.join(', '), '1, 2, 3', 'aliased as "forEach"');

    answers = [];
    var obj = {one : 1, two : 2, three : 3};
    obj.constructor.prototype.four = 4;
    _.each(obj, function(value, key){ answers.push(key); });
    equal(answers.join(", "), 'one, two, three', 'iterating over objects works, and ignores the object prototype.');
    delete obj.constructor.prototype.four;

    var answer = null;
    _.each([1, 2, 3], function(num, index, arr){ if (_.include(arr, num)) answer = true; });
    ok(answer, 'can reference the original collection from inside the iterator');

    answers = 0;
    _.each(null, function(){ ++answers; });
    equal(answers, 0, 'handles a null properly');
  });
        `)
	})
}

// map
func Test_underscore_collections_1(t *testing.T) {
	tt(t, func() {
		test, _ := test_()

		test(`
  test('map', function() {
    var doubled = _.map([1, 2, 3], function(num){ return num * 2; });
    equal(doubled.join(', '), '2, 4, 6', 'doubled numbers');

    doubled = _.collect([1, 2, 3], function(num){ return num * 2; });
    equal(doubled.join(', '), '2, 4, 6', 'aliased as "collect"');

    var tripled = _.map([1, 2, 3], function(num){ return num * this.multiplier; }, {multiplier : 3});
    equal(tripled.join(', '), '3, 6, 9', 'tripled numbers with context');

    var doubled = _([1, 2, 3]).map(function(num){ return num * 2; });
    equal(doubled.join(', '), '2, 4, 6', 'OO-style doubled numbers');

    // TEST: ReferenceError: document is not defined
    return;

    if (document.querySelectorAll) {
      var ids = _.map(document.querySelectorAll('#map-test *'), function(n){ return n.id; });
      deepEqual(ids, ['id1', 'id2'], 'Can use collection methods on NodeLists.');
    }

    var ids = _.map($('#map-test').children(), function(n){ return n.id; });
    deepEqual(ids, ['id1', 'id2'], 'Can use collection methods on jQuery Array-likes.');

    var ids = _.map(document.images, function(n){ return n.id; });
    ok(ids[0] == 'chart_image', 'can use collection methods on HTMLCollections');

    var ifnull = _.map(null, function(){});
    ok(_.isArray(ifnull) && ifnull.length === 0, 'handles a null properly');
  });
        `)
	})
}

// reduce
func Test_underscore_collections_2(t *testing.T) {
	tt(t, func() {
		test, _ := test_()

		test(`
  test('reduce', function() {
    var sum = _.reduce([1, 2, 3], function(sum, num){ return sum + num; }, 0);
    equal(sum, 6, 'can sum up an array');

    var context = {multiplier : 3};
    sum = _.reduce([1, 2, 3], function(sum, num){ return sum + num * this.multiplier; }, 0, context);
    equal(sum, 18, 'can reduce with a context object');

    sum = _.inject([1, 2, 3], function(sum, num){ return sum + num; }, 0);
    equal(sum, 6, 'aliased as "inject"');

    sum = _([1, 2, 3]).reduce(function(sum, num){ return sum + num; }, 0);
    equal(sum, 6, 'OO-style reduce');

    var sum = _.reduce([1, 2, 3], function(sum, num){ return sum + num; });
    equal(sum, 6, 'default initial value');

    var ifnull;
    try {
      _.reduce(null, function(){});
    } catch (ex) {
      ifnull = ex;
    }
    ok(ifnull instanceof TypeError, 'handles a null (without inital value) properly');

    ok(_.reduce(null, function(){}, 138) === 138, 'handles a null (with initial value) properly');
    equal(_.reduce([], function(){}, undefined), undefined, 'undefined can be passed as a special case');
    raises(function() { _.reduce([], function(){}); }, TypeError, 'throws an error for empty arrays with no initial value');
  });
        `)
	})
}

// reduceRight
func Test_underscore_collections_3(t *testing.T) {
	tt(t, func() {
		test, _ := test_()

		test(`
  test('reduceRight', function() {
    var list = _.reduceRight(["foo", "bar", "baz"], function(memo, str){ return memo + str; }, '');
    equal(list, 'bazbarfoo', 'can perform right folds');

    var list = _.foldr(["foo", "bar", "baz"], function(memo, str){ return memo + str; }, '');
    equal(list, 'bazbarfoo', 'aliased as "foldr"');

    var list = _.foldr(["foo", "bar", "baz"], function(memo, str){ return memo + str; });
    equal(list, 'bazbarfoo', 'default initial value');

    var ifnull;
    try {
      _.reduceRight(null, function(){});
    } catch (ex) {
      ifnull = ex;
    }
    ok(ifnull instanceof TypeError, 'handles a null (without inital value) properly');

    var sum = _.reduceRight({a: 1, b: 2, c: 3}, function(sum, num){ return sum + num; });
    equal(sum, 6, 'default initial value on object');

    ok(_.reduceRight(null, function(){}, 138) === 138, 'handles a null (with initial value) properly');

    equal(_.reduceRight([], function(){}, undefined), undefined, 'undefined can be passed as a special case');
    raises(function() { _.reduceRight([], function(){}); }, TypeError, 'throws an error for empty arrays with no initial value');

    // Assert that the correct arguments are being passed.

    var args,
        memo = {},
        object = {a: 1, b: 2},
        lastKey = _.keys(object).pop();

    var expected = lastKey == 'a'
      ? [memo, 1, 'a', object]
      : [memo, 2, 'b', object];

    _.reduceRight(object, function() {
      args || (args = _.toArray(arguments));
    }, memo);

    deepEqual(args, expected);

    // And again, with numeric keys.

    object = {'2': 'a', '1': 'b'};
    lastKey = _.keys(object).pop();
    args = null;

    expected = lastKey == '2'
      ? [memo, 'a', '2', object]
      : [memo, 'b', '1', object];

    _.reduceRight(object, function() {
      args || (args = _.toArray(arguments));
    }, memo);

    deepEqual(args, expected);
  });
        `)
	})
}

// find
func Test_underscore_collections_4(t *testing.T) {
	tt(t, func() {
		test, _ := test_()

		test(`
  test('find', function() {
    var array = [1, 2, 3, 4];
    strictEqual(_.find(array, function(n) { return n > 2; }), 3, 'should return first found <value>');
    strictEqual(_.find(array, function() { return false; }), void 0, 'should return <undefined> if <value> is not found');
  });
        `)
	})
}

// detect
func Test_underscore_collections_5(t *testing.T) {
	tt(t, func() {
		test, _ := test_()

		test(`
  test('detect', function() {
    var result = _.detect([1, 2, 3], function(num){ return num * 2 == 4; });
    equal(result, 2, 'found the first "2" and broke the loop');
  });
        `)
	})
}

// select
func Test_underscore_collections_6(t *testing.T) {
	tt(t, func() {
		test, _ := test_()

		test(`
  test('select', function() {
    var evens = _.select([1, 2, 3, 4, 5, 6], function(num){ return num % 2 == 0; });
    equal(evens.join(', '), '2, 4, 6', 'selected each even number');

    evens = _.filter([1, 2, 3, 4, 5, 6], function(num){ return num % 2 == 0; });
    equal(evens.join(', '), '2, 4, 6', 'aliased as "filter"');
  });
        `)
	})
}

// reject
func Test_underscore_collections_7(t *testing.T) {
	tt(t, func() {
		test, _ := test_()

		test(`
  test('reject', function() {
    var odds = _.reject([1, 2, 3, 4, 5, 6], function(num){ return num % 2 == 0; });
    equal(odds.join(', '), '1, 3, 5', 'rejected each even number');

    var context = "obj";

    var evens = _.reject([1, 2, 3, 4, 5, 6], function(num){
      equal(context, "obj");
      return num % 2 != 0;
    }, context);
    equal(evens.join(', '), '2, 4, 6', 'rejected each odd number');
  });
        `)
	})
}

// all
func Test_underscore_collections_8(t *testing.T) {
	tt(t, func() {
		test, _ := test_()

		test(`
  test('all', function() {
    ok(_.all([], _.identity), 'the empty set');
    ok(_.all([true, true, true], _.identity), 'all true values');
    ok(!_.all([true, false, true], _.identity), 'one false value');
    ok(_.all([0, 10, 28], function(num){ return num % 2 == 0; }), 'even numbers');
    ok(!_.all([0, 11, 28], function(num){ return num % 2 == 0; }), 'an odd number');
    ok(_.all([1], _.identity) === true, 'cast to boolean - true');
    ok(_.all([0], _.identity) === false, 'cast to boolean - false');
    ok(_.every([true, true, true], _.identity), 'aliased as "every"');
    ok(!_.all([undefined, undefined, undefined], _.identity), 'works with arrays of undefined');
  });
        `)
	})
}

// any
func Test_underscore_collections_9(t *testing.T) {
	tt(t, func() {
		test, _ := test_()

		test(`
  test('any', function() {
    var nativeSome = Array.prototype.some;
    Array.prototype.some = null;
    ok(!_.any([]), 'the empty set');
    ok(!_.any([false, false, false]), 'all false values');
    ok(_.any([false, false, true]), 'one true value');
    ok(_.any([null, 0, 'yes', false]), 'a string');
    ok(!_.any([null, 0, '', false]), 'falsy values');
    ok(!_.any([1, 11, 29], function(num){ return num % 2 == 0; }), 'all odd numbers');
    ok(_.any([1, 10, 29], function(num){ return num % 2 == 0; }), 'an even number');
    ok(_.any([1], _.identity) === true, 'cast to boolean - true');
    ok(_.any([0], _.identity) === false, 'cast to boolean - false');
    ok(_.some([false, false, true]), 'aliased as "some"');
    Array.prototype.some = nativeSome;
  });
        `)
	})
}

// include
func Test_underscore_collections_10(t *testing.T) {
	tt(t, func() {
		test, _ := test_()

		test(`
  test('include', function() {
    ok(_.include([1,2,3], 2), 'two is in the array');
    ok(!_.include([1,3,9], 2), 'two is not in the array');
    ok(_.contains({moe:1, larry:3, curly:9}, 3) === true, '_.include on objects checks their values');
    ok(_([1,2,3]).include(2), 'OO-style include');
  });
        `)
	})
}

// invoke
func Test_underscore_collections_11(t *testing.T) {
	tt(t, func() {
		test, _ := test_()

		test(`
  test('invoke', function() {
    var list = [[5, 1, 7], [3, 2, 1]];
    var result = _.invoke(list, 'sort');
    equal(result[0].join(', '), '1, 5, 7', 'first array sorted');
    equal(result[1].join(', '), '1, 2, 3', 'second array sorted');
  });
        `)
	})
}

// invoke w/ function reference
func Test_underscore_collections_12(t *testing.T) {
	tt(t, func() {
		test, _ := test_()

		test(`
  test('invoke w/ function reference', function() {
    var list = [[5, 1, 7], [3, 2, 1]];
    var result = _.invoke(list, Array.prototype.sort);
    equal(result[0].join(', '), '1, 5, 7', 'first array sorted');
    equal(result[1].join(', '), '1, 2, 3', 'second array sorted');
  });
        `)
	})
}

// invoke when strings have a call method
func Test_underscore_collections_13(t *testing.T) {
	tt(t, func() {
		test, _ := test_()

		test(`
  test('invoke when strings have a call method', function() {
    String.prototype.call = function() {
      return 42;
    };
    var list = [[5, 1, 7], [3, 2, 1]];
    var s = "foo";
    equal(s.call(), 42, "call function exists");
    var result = _.invoke(list, 'sort');
    equal(result[0].join(', '), '1, 5, 7', 'first array sorted');
    equal(result[1].join(', '), '1, 2, 3', 'second array sorted');
    delete String.prototype.call;
    equal(s.call, undefined, "call function removed");
  });
        `)
	})
}

// pluck
func Test_underscore_collections_14(t *testing.T) {
	tt(t, func() {
		test, _ := test_()

		test(`
  test('pluck', function() {
    var people = [{name : 'moe', age : 30}, {name : 'curly', age : 50}];
    equal(_.pluck(people, 'name').join(', '), 'moe, curly', 'pulls names out of objects');
  });
        `)
	})
}

// where
func Test_underscore_collections_15(t *testing.T) {
	tt(t, func() {
		test, _ := test_()

		test(`
  test('where', function() {
    var list = [{a: 1, b: 2}, {a: 2, b: 2}, {a: 1, b: 3}, {a: 1, b: 4}];
    var result = _.where(list, {a: 1});
    equal(result.length, 3);
    equal(result[result.length - 1].b, 4);
    result = _.where(list, {b: 2});
    equal(result.length, 2);
    equal(result[0].a, 1);
  });
        `)
	})
}

// findWhere
func Test_underscore_collections_16(t *testing.T) {
	tt(t, func() {
		test, _ := test_()

		test(`
  test('findWhere', function() {
    var list = [{a: 1, b: 2}, {a: 2, b: 2}, {a: 1, b: 3}, {a: 1, b: 4}, {a: 2, b: 4}];
    var result = _.findWhere(list, {a: 1});
    deepEqual(result, {a: 1, b: 2});
    result = _.findWhere(list, {b: 4});
    deepEqual(result, {a: 1, b: 4});
  });
        `)
	})
}

// max
func Test_underscore_collections_17(t *testing.T) {
	tt(t, func() {
		test, _ := test_()

		test(`
  test('max', function() {
    equal(3, _.max([1, 2, 3]), 'can perform a regular Math.max');

    var neg = _.max([1, 2, 3], function(num){ return -num; });
    equal(neg, 1, 'can perform a computation-based max');

    equal(-Infinity, _.max({}), 'Maximum value of an empty object');
    equal(-Infinity, _.max([]), 'Maximum value of an empty array');
    equal(_.max({'a': 'a'}), -Infinity, 'Maximum value of a non-numeric collection');

    // TEST: Takes too long
    return;

    equal(299999, _.max(_.range(1,300000)), "Maximum value of a too-big array");
  });
        `)
	})
}

// min
func Test_underscore_collections_18(t *testing.T) {
	tt(t, func() {
		test, _ := test_()

		test(`
  test('min', function() {
    equal(1, _.min([1, 2, 3]), 'can perform a regular Math.min');

    var neg = _.min([1, 2, 3], function(num){ return -num; });
    equal(neg, 3, 'can perform a computation-based min');

    equal(Infinity, _.min({}), 'Minimum value of an empty object');
    equal(Infinity, _.min([]), 'Minimum value of an empty array');
    equal(_.min({'a': 'a'}), Infinity, 'Minimum value of a non-numeric collection');

    var now = new Date(9999999999);
    var then = new Date(0);
    equal(_.min([now, then]), then);

    // TEST: Takes too long
    return;

    equal(1, _.min(_.range(1,300000)), "Minimum value of a too-big array");
  });
        `)
	})
}

// sortBy
func Test_underscore_collections_19(t *testing.T) {
	tt(t, func() {
		test, _ := test_()

		test(`
  test('sortBy', function() {
    var people = [{name : 'curly', age : 50}, {name : 'moe', age : 30}];
    people = _.sortBy(people, function(person){ return person.age; });
    equal(_.pluck(people, 'name').join(', '), 'moe, curly', 'stooges sorted by age');

    var list = [undefined, 4, 1, undefined, 3, 2];
    equal(_.sortBy(list, _.identity).join(','), '1,2,3,4,,', 'sortBy with undefined values');

    var list = ["one", "two", "three", "four", "five"];
    var sorted = _.sortBy(list, 'length');
    equal(sorted.join(' '), 'one two four five three', 'sorted by length');

    function Pair(x, y) {
      this.x = x;
      this.y = y;
    }

    var collection = [
      new Pair(1, 1), new Pair(1, 2),
      new Pair(1, 3), new Pair(1, 4),
      new Pair(1, 5), new Pair(1, 6),
      new Pair(2, 1), new Pair(2, 2),
      new Pair(2, 3), new Pair(2, 4),
      new Pair(2, 5), new Pair(2, 6),
      new Pair(undefined, 1), new Pair(undefined, 2),
      new Pair(undefined, 3), new Pair(undefined, 4),
      new Pair(undefined, 5), new Pair(undefined, 6)
    ];

    var actual = _.sortBy(collection, function(pair) {
      return pair.x;
    });

    deepEqual(actual, collection, 'sortBy should be stable');
  });
        `)
	})
}

// groupBy
func Test_underscore_collections_20(t *testing.T) {
	tt(t, func() {
		test, _ := test_()

		test(`
  test('groupBy', function() {
    var parity = _.groupBy([1, 2, 3, 4, 5, 6], function(num){ return num % 2; });
    ok('0' in parity && '1' in parity, 'created a group for each value');
    equal(parity[0].join(', '), '2, 4, 6', 'put each even number in the right group');

    var list = ["one", "two", "three", "four", "five", "six", "seven", "eight", "nine", "ten"];
    var grouped = _.groupBy(list, 'length');
    equal(grouped['3'].join(' '), 'one two six ten');
    equal(grouped['4'].join(' '), 'four five nine');
    equal(grouped['5'].join(' '), 'three seven eight');

    var context = {};
    _.groupBy([{}], function(){ ok(this === context); }, context);

    grouped = _.groupBy([4.2, 6.1, 6.4], function(num) {
      return Math.floor(num) > 4 ? 'hasOwnProperty' : 'constructor';
    });
    equal(grouped.constructor.length, 1);
    equal(grouped.hasOwnProperty.length, 2);

    var array = [{}];
    _.groupBy(array, function(value, index, obj){ ok(obj === array); });

    var array = [1, 2, 1, 2, 3];
    var grouped = _.groupBy(array);
    equal(grouped['1'].length, 2);
    equal(grouped['3'].length, 1);
  });
        `)
	})
}

// countBy
func Test_underscore_collections_21(t *testing.T) {
	tt(t, func() {
		test, _ := test_()

		test(`
  test('countBy', function() {
    var parity = _.countBy([1, 2, 3, 4, 5], function(num){ return num % 2 == 0; });
    equal(parity['true'], 2);
    equal(parity['false'], 3);

    var list = ["one", "two", "three", "four", "five", "six", "seven", "eight", "nine", "ten"];
    var grouped = _.countBy(list, 'length');
    equal(grouped['3'], 4);
    equal(grouped['4'], 3);
    equal(grouped['5'], 3);

    var context = {};
    _.countBy([{}], function(){ ok(this === context); }, context);

    grouped = _.countBy([4.2, 6.1, 6.4], function(num) {
      return Math.floor(num) > 4 ? 'hasOwnProperty' : 'constructor';
    });
    equal(grouped.constructor, 1);
    equal(grouped.hasOwnProperty, 2);

    var array = [{}];
    _.countBy(array, function(value, index, obj){ ok(obj === array); });

    var array = [1, 2, 1, 2, 3];
    var grouped = _.countBy(array);
    equal(grouped['1'], 2);
    equal(grouped['3'], 1);
  });
        `)
	})
}

// sortedIndex
func Test_underscore_collections_22(t *testing.T) {
	tt(t, func() {
		test, _ := test_()

		test(`
  test('sortedIndex', function() {
    var numbers = [10, 20, 30, 40, 50], num = 35;
    var indexForNum = _.sortedIndex(numbers, num);
    equal(indexForNum, 3, '35 should be inserted at index 3');

    var indexFor30 = _.sortedIndex(numbers, 30);
    equal(indexFor30, 2, '30 should be inserted at index 2');

    var objects = [{x: 10}, {x: 20}, {x: 30}, {x: 40}];
    var iterator = function(obj){ return obj.x; };
    strictEqual(_.sortedIndex(objects, {x: 25}, iterator), 2);
    strictEqual(_.sortedIndex(objects, {x: 35}, 'x'), 3);

    var context = {1: 2, 2: 3, 3: 4};
    iterator = function(obj){ return this[obj]; };
    strictEqual(_.sortedIndex([1, 3], 2, iterator, context), 1);
  });
        `)
	})
}

// shuffle
func Test_underscore_collections_23(t *testing.T) {
	tt(t, func() {
		test, _ := test_()

		test(`
  test('shuffle', function() {
    var numbers = _.range(10);
    var shuffled = _.shuffle(numbers).sort();
    notStrictEqual(numbers, shuffled, 'original object is unmodified');
    equal(shuffled.join(','), numbers.join(','), 'contains the same members before and after shuffle');
  });
        `)
	})
}

// toArray
func Test_underscore_collections_24(t *testing.T) {
	tt(t, func() {
		test, _ := test_()

		test(`
  test('toArray', function() {
    ok(!_.isArray(arguments), 'arguments object is not an array');
    ok(_.isArray(_.toArray(arguments)), 'arguments object converted into array');
    var a = [1,2,3];
    ok(_.toArray(a) !== a, 'array is cloned');
    equal(_.toArray(a).join(', '), '1, 2, 3', 'cloned array contains same elements');

    var numbers = _.toArray({one : 1, two : 2, three : 3});
    equal(numbers.join(', '), '1, 2, 3', 'object flattened into array');

    // TEST: ReferenceError: document is not defined
    return;

    // test in IE < 9
    try {
      var actual = _.toArray(document.childNodes);
    } catch(ex) { }

    ok(_.isArray(actual), 'should not throw converting a node list');
  });
        `)
	})
}

// size
func Test_underscore_collections_25(t *testing.T) {
	tt(t, func() {
		test, _ := test_()

		test(`
  test('size', function() {
    equal(_.size({one : 1, two : 2, three : 3}), 3, 'can compute the size of an object');
    equal(_.size([1, 2, 3]), 3, 'can compute the size of an array');

    var func = function() {
      return _.size(arguments);
    };

    equal(func(1, 2, 3, 4), 4, 'can test the size of the arguments object');

    equal(_.size('hello'), 5, 'can compute the size of a string');

    equal(_.size(null), 0, 'handles nulls');
  });
        `)
	})
}