fun-apply-null-undefined.js

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function testBasic() {

    var thisVal = {};

    var arr = [1, 2, 3];

    var f = function() {

        assertEq(this, thisVal);

        assertEq(arguments.length, 0);

        return 456;

};

    var boundMathAbs = Math.abs.bind();

    var boundArrayJoin = Array.prototype.join.bind(arr);

    var boundArrayJoinArg = Array.prototype.join.bind(arr, "-");

    for (var i = 0; i < 100; i++) {

        // Scripted callee.

        assertEq(f.apply(thisVal), 456);

        assertEq(f.apply(thisVal), 456);

        assertEq(f.apply(thisVal, null), 456);

        assertEq(f.apply(thisVal, undefined), 456);

        // Native callee.

        assertEq(Math.abs.apply(), NaN);

        assertEq(Math.abs.apply(null), NaN);

        assertEq(Math.abs.apply(null, null), NaN);

        assertEq(Array.prototype.join.apply(arr), "1,2,3");

        assertEq(Array.prototype.join.apply(arr, null), "1,2,3");

        assertEq(Array.prototype.join.apply(arr, undefined), "1,2,3");

        // Bound native callee.

        assertEq(boundMathAbs.apply(), NaN);

        assertEq(boundMathAbs.apply(null), NaN);

        assertEq(boundMathAbs.apply(null, null), NaN);

        assertEq(boundMathAbs.apply(null, undefined), NaN);

        assertEq(boundArrayJoin.apply(), "1,2,3");

        assertEq(boundArrayJoin.apply(null), "1,2,3");

        assertEq(boundArrayJoin.apply(null, null), "1,2,3");

        assertEq(boundArrayJoin.apply(null, undefined), "1,2,3");

        assertEq(boundArrayJoinArg.apply(), "1-2-3");

        assertEq(boundArrayJoinArg.apply(null), "1-2-3");

        assertEq(boundArrayJoinArg.apply(null, null), "1-2-3");

        assertEq(boundArrayJoinArg.apply(null, undefined), "1-2-3");

testBasic();

function testUndefinedGuard() {

    var f = function() { return arguments.length; }

    var arr = [-5, 5];

    var strings = ["a", "b"];

    var boundMathAbs = Math.abs.bind();

    var boundArrayJoin = Array.prototype.join.bind(strings);

    for (var i = 0; i < 100; i++) {

        var args = i < 50 ? undefined : arr;

        assertEq(f.apply(null, args), i < 50 ? 0 : 2);

        assertEq(Math.abs.apply(null, args), i < 50 ? NaN : 5);

        assertEq(Array.prototype.join.apply(strings, args), i < 50 ? "a,b" : "a-5b");

        assertEq(boundMathAbs.apply(null, args), i < 50 ? NaN : 5);

        assertEq(boundArrayJoin.apply(null, args), i < 50 ? "a,b" : "a-5b");

testUndefinedGuard();