(function() {
"use strict";

// SERVER-20332 make JS NumberLong more robust
//
// Make sure swapping floatApprox, top and bottom don't break NumberLong

// Picking 2^54 because it's representable as a double (as a power of
// two), but big enough that the NumberLong code doesn't know it (numbers
// over 2^53 can lose precision)
var number = NumberLong("18014398509481984");

{
    // Make sure all elements in a new NumberLong are valid

    assert.eq(number.floatApprox, 18014398509481984);
    assert.eq(number.top, 4194304);
    assert.eq(number.bottom, 0);
    assert.eq(number.valueOf(), 18014398509481984);
}

{
    // Make sure that floatApprox, top and bottom cannot be set

    assert.throws(function() {
        number.floatApprox = "a";
    }, [], "floatApprox should not be setable.");

    assert.throws(function() {
        number.top = "a";
    }, [], "top should not be setable.");

    assert.throws(function() {
        number.bottom = "a";
    }, [], "bottom should not be setable.");
}

{
    // Make sure we fall back to floatApprox

    delete number.top;
    delete number.bottom;

    assert.eq(number.valueOf(), 18014398509481984);
}
})();