LayoutTests/js/script-tests/array-reduce.js

description(
"This test checks the behavior of the reduce() method on a number of objects."
);

function toObject(array) {
    var o = {};
    for (var i in array)
        o[i] = array[i];
    o.length = array.length;
    o.reduce = Array.prototype.reduce;
    return o;
}
function toUnorderedObject(array) {
    var o = {};
    var props = [];
    for (var i in array)
        props.push(i);
    for (var i = props.length - 1; i >= 0; i--)
        o[props[i]] = array[props[i]];
    o.length = array.length;
    o.reduce = Array.prototype.reduce;
    return o;
}

shouldBe("[0,1,2,3].reduce(function(a,b){ return a + b; })", "6");
shouldBe("[1,2,3].reduce(function(a,b){ return a + b; })", "6");
shouldBe("[0,1,2,3].reduce(function(a,b){ return a + b; }, 4)", "10");
shouldBe("[1,2,3].reduce(function(a,b){ return a + b; }, 4)", "10");
shouldBe("toObject([0,1,2,3]).reduce(function(a,b){ return a + b; })", "6");
shouldBe("toObject([1,2,3]).reduce(function(a,b){ return a + b; })", "6");
shouldBe("toObject([0,1,2,3]).reduce(function(a,b){ return a + b; }, 4)", "10");
shouldBe("toObject([1,2,3]).reduce(function(a,b){ return a + b; }, 4)", "10");
shouldBe("toUnorderedObject([0,1,2,3]).reduce(function(a,b){ return a + b; })", "6");
shouldBe("toUnorderedObject([1,2,3]).reduce(function(a,b){ return a + b; })", "6");
shouldBe("toUnorderedObject([0,1,2,3]).reduce(function(a,b){ return a + b; }, 4)", "10");
shouldBe("toUnorderedObject([1,2,3]).reduce(function(a,b){ return a + b; }, 4)", "10");
sparseArray = [];
sparseArray[10] = 10;
shouldBe("sparseArray.reduce(function(a,b){ return a + b; }, 0)", "10");
shouldBe("toObject(sparseArray).reduce(function(a,b){ return a + b; }, 0)", "10");
var callCount = 0;
shouldBe("sparseArray.reduce(function(a,b){ callCount++; }); callCount", "0");
callCount = 0;
shouldBe("toObject(sparseArray).reduce(function(a,b){ callCount++; }); callCount", "0");
var callCount = 0;
shouldBe("sparseArray.reduce(function(a,b){ callCount++; }, 0); callCount", "1");
callCount = 0;
shouldBe("toObject(sparseArray).reduce(function(a,b){ callCount++; }, 0); callCount", "1");
callCount = 0;
shouldBe("[0,1,2,3,4].reduce(function(a,b){ callCount++; }, 0); callCount", "5");
callCount = 0;
shouldBe("[0,1,2,3,4].reduce(function(a,b){ callCount++; }); callCount", "4");
callCount = 0;
shouldBe("[1, 2, 3, 4].reduce(function(a,b, i, thisObj){ thisObj.length--; callCount++; return a + b; }, 0); callCount", "2");
callCount = 0;
shouldBe("[1, 2, 3, 4].reduce(function(a,b, i, thisObj){ thisObj.length++; callCount++; return a + b; }, 0); callCount", "4");
callCount = 0;
shouldBe("toObject([1, 2, 3, 4]).reduce(function(a,b, i, thisObj){ thisObj.length--; callCount++; return a + b; }, 0); callCount", "4");
callCount = 0;
shouldBe("toObject([1, 2, 3, 4]).reduce(function(a,b, i, thisObj){ thisObj.length++; callCount++; return a + b; }, 0); callCount", "4");

shouldBe("[[0,1], [2,3], [4,5]].reduce(function(a,b) {return a.concat(b);}, [])", "[0,1,2,3,4,5]");
shouldBe("toObject([[0,1], [2,3], [4,5]]).reduce(function(a,b) {return a.concat(b);}, [])", "[0,1,2,3,4,5]");
shouldBe("toObject([0,1,2,3,4,5]).reduce(function(a,b,i) {return a.concat([i,b]);}, [])", "[0,0,1,1,2,2,3,3,4,4,5,5]");
shouldBe("toUnorderedObject([[0,1], [2,3], [4,5]]).reduce(function(a,b) {return a.concat(b);}, [])", "[0,1,2,3,4,5]");
shouldBe("toUnorderedObject([0,1,2,3,4,5]).reduce(function(a,b,i) {return a.concat([i,b]);}, [])", "[0,0,1,1,2,2,3,3,4,4,5,5]");
shouldBe("[0,1,2,3,4,5].reduce(function(a,b,i) {return a.concat([i,b]);}, [])", "[0,0,1,1,2,2,3,3,4,4,5,5]");
shouldBe("[2,3].reduce(function() {'use strict'; return this;})", "undefined");

var negativeLengthObject = { length: -1, 0: 1, 1: 2 };
shouldBe("Array.prototype.reduce.call(negativeLengthObject, function (a, b) { return a + b; }, 100)", "100");