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"use strict";
var conversions = {};
module.exports = conversions;
function sign(x) {
return x < 0 ? -1 : 1;
}
function evenRound(x) {
// Round x to the nearest integer, choosing the even integer if it lies halfway between two.
if ((x % 1) === 0.5 && (x & 1) === 0) { // [even number].5; round down (i.e. floor)
return Math.floor(x);
} else {
return Math.round(x);
}
}
function createNumberConversion(bitLength, typeOpts) {
if (!typeOpts.unsigned) {
--bitLength;
}
const lowerBound = typeOpts.unsigned ? 0 : -Math.pow(2, bitLength);
const upperBound = Math.pow(2, bitLength) - 1;
const moduloVal = typeOpts.moduloBitLength ? Math.pow(2, typeOpts.moduloBitLength) : Math.pow(2, bitLength);
const moduloBound = typeOpts.moduloBitLength ? Math.pow(2, typeOpts.moduloBitLength - 1) : Math.pow(2, bitLength - 1);
return function(V, opts) {
if (!opts) opts = {};
let x = +V;
if (opts.enforceRange) {
if (!Number.isFinite(x)) {
throw new TypeError("Argument is not a finite number");
}
x = sign(x) * Math.floor(Math.abs(x));
if (x < lowerBound || x > upperBound) {
throw new TypeError("Argument is not in byte range");
}
return x;
}
if (!isNaN(x) && opts.clamp) {
x = evenRound(x);
if (x < lowerBound) x = lowerBound;
if (x > upperBound) x = upperBound;
return x;
}
if (!Number.isFinite(x) || x === 0) {
return 0;
}
x = sign(x) * Math.floor(Math.abs(x));
x = x % moduloVal;
if (!typeOpts.unsigned && x >= moduloBound) {
return x - moduloVal;
} else if (typeOpts.unsigned) {
if (x < 0) {
x += moduloVal;
} else if (x === -0) { // don't return negative zero
return 0;
}
}
return x;
}
}
conversions["void"] = function () {
return undefined;
};
conversions["boolean"] = function (val) {
return !!val;
};
conversions["byte"] = createNumberConversion(8, { unsigned: false });
conversions["octet"] = createNumberConversion(8, { unsigned: true });
conversions["short"] = createNumberConversion(16, { unsigned: false });
conversions["unsigned short"] = createNumberConversion(16, { unsigned: true });
conversions["long"] = createNumberConversion(32, { unsigned: false });
conversions["unsigned long"] = createNumberConversion(32, { unsigned: true });
conversions["long long"] = createNumberConversion(32, { unsigned: false, moduloBitLength: 64 });
conversions["unsigned long long"] = createNumberConversion(32, { unsigned: true, moduloBitLength: 64 });
conversions["double"] = function (V) {
const x = +V;
if (!Number.isFinite(x)) {
throw new TypeError("Argument is not a finite floating-point value");
}
return x;
};
conversions["unrestricted double"] = function (V) {
const x = +V;
if (isNaN(x)) {
throw new TypeError("Argument is NaN");
}
return x;
};
// not quite valid, but good enough for JS
conversions["float"] = conversions["double"];
conversions["unrestricted float"] = conversions["unrestricted double"];
conversions["DOMString"] = function (V, opts) {
if (!opts) opts = {};
if (opts.treatNullAsEmptyString && V === null) {
return "";
}
return String(V);
};
conversions["ByteString"] = function (V, opts) {
const x = String(V);
let c = undefined;
for (let i = 0; (c = x.codePointAt(i)) !== undefined; ++i) {
if (c > 255) {
throw new TypeError("Argument is not a valid bytestring");
}
}
return x;
};
conversions["USVString"] = function (V) {
const S = String(V);
const n = S.length;
const U = [];
for (let i = 0; i < n; ++i) {
const c = S.charCodeAt(i);
if (c < 0xD800 || c > 0xDFFF) {
U.push(String.fromCodePoint(c));
} else if (0xDC00 <= c && c <= 0xDFFF) {
U.push(String.fromCodePoint(0xFFFD));
} else {
if (i === n - 1) {
U.push(String.fromCodePoint(0xFFFD));
} else {
const d = S.charCodeAt(i + 1);
if (0xDC00 <= d && d <= 0xDFFF) {
const a = c & 0x3FF;
const b = d & 0x3FF;
U.push(String.fromCodePoint((2 << 15) + (2 << 9) * a + b));
++i;
} else {
U.push(String.fromCodePoint(0xFFFD));
}
}
}
}
return U.join('');
};
conversions["Date"] = function (V, opts) {
if (!(V instanceof Date)) {
throw new TypeError("Argument is not a Date object");
}
if (isNaN(V)) {
return undefined;
}
return V;
};
conversions["RegExp"] = function (V, opts) {
if (!(V instanceof RegExp)) {
V = new RegExp(V);
}
return V;
};