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"use strict";
/* globals define */
define(function () {
/**
* A class which appears to act like the Date class with customizable timezone
* offsets.
*
* @param {string} iso8601String An ISO-8601 date/time string including a
* timezone offset.
*/
function MockDate(iso8601String) {
// Find the timezone offset (Z or ±hhmm) from the ISO-8601 date string, and
// then convert that into a number of minutes.
const parse = /\d{4}-\d\d-\d\dT\d\d:\d\d:\d\d(Z|[+-]\d{4})/.exec(
iso8601String
);
const tzOffsetStr = parse[1];
if (tzOffsetStr == "Z") {
this._tzOffset = 0;
} else {
this._tzOffset =
parseInt(tzOffsetStr.substring(1, 3)) * 60 +
parseInt(tzOffsetStr.substring(3));
if (tzOffsetStr[0] == "-") {
this._tzOffset = -this._tzOffset;
}
}
// To store the offset, we store both the real time in _realDate and a time
// that is offset by the tzOffset in _shiftedDate. Only the getUTC* methods
// should be used on these properties, to avoid problems caused by daylight
// savings time or other timezone effects. This shifting is always legal
// because ES6 is specified to assume that leap seconds do not exist, so there
// are always 60 seconds in a minute.
this._realDate = new Date(iso8601String);
this._shiftedDate = new Date(
this._realDate.getTime() + this._tzOffset * 60 * 1000
);
}
MockDate.prototype = {
getTimezoneOffset() {
// This property is reversed from how it's defined in ISO 8601, i.e.,
// UTC +0100 needs to return -60.
return -this._tzOffset;
},
getTime() {
return this._realDate.getTime();
},
};
// Provide an implementation of Date methods that will be need in JSMime. For
// the time being, we only need .get* methods.
for (const name of Object.getOwnPropertyNames(Date.prototype)) {
// Only copy getters, not setters or x.toString.
if (!name.startsWith("get")) {
continue;
}
// No redefining any other names on MockDate.
if (MockDate.prototype.hasOwnProperty(name)) {
continue;
}
if (name.includes("UTC")) {
// 'name' is already supposed to be freshly bound per newest ES6 drafts, but
// current ES6 implementations reuse the bindings. Until implementations
// catch up, use a new let to bind it freshly.
const boundName = name;
Object.defineProperty(MockDate.prototype, name, {
value(...aArgs) {
return Date.prototype[boundName].call(this._realDate, aArgs);
},
});
} else {
const newName = "getUTC" + name.substr(3);
Object.defineProperty(MockDate.prototype, name, {
value(...aArgs) {
return Date.prototype[newName].call(this._shiftedDate, aArgs);
},
});
}
}
return MockDate;
});