1.3.2

.prettierignore

@@ -0,0 +1 @@
+*.min.js

.prettierrc.json

@@ -0,0 +1,7 @@
+{
+  "printWidth": 80,
+  "tabWidth": 2,
+  "singleQuote": false,
+  "bracketSpacing": true,
+  "semi": true
+}

README.md

@@ -1,64 +1,62 @@
 # [xtz.js](https://github.com/therootcompany/tz.js)
 
-A fast, lightweight, zero-dependency library to
+A fast, lightweight, zero-dependency library to translate between Time Zones and UTC with native `Intl.DateTimeFormat`
-translate between Time Zones and UTC with native
+in ~100 LoC. For Node.js & Browsers.
-`Intl.DateTimeFormat` in ~100 LoC. For Node.js & Browsers.
 
-XTZ is a poor man's Temporal polyfill, but just for time zones.
+[![](./xtz-preview.png)](https://therootcompany.github.io/tz.js/)
 
-> What UTC time will it be when it's 3:15am in New York?
+XTZ is a poor man's `Temporal` polyfill, but just for time zones. \
+Demo: <https://therootcompany.github.io/tz.js/>
 
 ```js
-// Relative New York time to Absolute UTC Time
+// What's the current time, in ISO+Offset format?
-TZ.toUTCISOString("2021-11-07 03:15:59.000", "America/New_York");
+
+TZ.toLocalISOString(new Date()); // "2021-11-07T03:15:59.000-0500"
+TZ.timeZone(); // "America/New_York"
+```
+
+```js
+// What will the ISO+Offset datetime string be
+// when it's 3:15am in New York?
+//
+// (Relative New York time to Absolute ISO+Offset Time)
+
+TZ.toOffsetISOString("2021-11-07 03:15:59.000", "America/New_York");
 // "2021-11-07T03:15:59.000-0500"
 ```
 
 ```js
-var tzDate = TZ.toUTC("2021-11-07 03:15:59.000", "America/New_York");
+// What time will it be in New York
-// {
+// when it's 7:15am UTC?
-//   year: 2021, month: 11, day: 7,
+//
-//   hour: 3, minute: 15, second: 59, millisecond: 0,
+// (Absolute UTC Zulu time to Relative New York time)
-//   offset: -300, timeZoneName: "Eastern Standard Time"
-// }
 
-tzDate.toISOString();
+TZ.toTimeZoneISOString("2021-03-14T07:15:59.000Z", "America/New_York");
-// "2021-11-07T03:15:59.000-0500"
-// same as "2021-11-07T08:15:59.000Z"
-```
-
-> What time will it be in New York when it's 7:15am UTC?
-
-```js
-// Absolute UTC time to Relative New York time
-TZ.toTimeZoneISOString("2021-11-07T07:15:59.000Z", "America/New_York");
-// "2021-11-07T03:15:59.000-0400"
-```
-
-```js
-var utcDate = TZ.toTimeZone("2021-03-14T07:15:59.000Z", "America/New_York");
-// {
-//   year: 2021, month: 3, day: 14,
-//   hour: 3, minute: 15, second: 59, millisecond: 0,
-//   offset: -240, timeZoneName: "Eastern Daylight Time"
-// }
-
-utcDate.toISOString();
 // "2021-03-14T03:15:59.000-0400"
-// same as "2021-11-07T07:15:59.000Z"
 ```
 
 # Features
 
--   [x] Translate a UTC time to a Time Zone
+- [x] Translate a UTC Zulu time to a Time Zone
--   [x] Translate a Zoned time to UTC
+- [x] Translate a Zoned time to ISO+Offset
--   [x] Handles **Daylight Savings**, Weird Time Zones, etc...
+- [x] Handles **Daylight Savings**, Weird Time Zones, etc...
--   [x] Lightweight (No deps)
+  - [x] Well-tested `npm run test`
-    -   5kb Source + Comments
+- [x] Lightweight (No deps)
-    -   2.5kb Minified
+  - 5kb Source + Comments
-    -   <1kb `gzip`d
+  - 2.5kb Minified
+  - <1kb `gzip`d
 
-Compatible with Node.js & Browsers.
+Compatible with Browsers, and Node.js.
+
+## Browsers
+
+```html
+<script src="https://unpkg.com/xtz@latest/xtz.min.js"></script>
+```
+
+```js
+var TZ = window.XTZ;
+```
 
 ## Node.js & Webpack
 
@@ -70,52 +68,69 @@ npm install --save xtz
 var TZ = require("xtz");
 ```
 
-## Browsers
+## Demo
 
-```html
+See <https://therootcompany.github.io/tz.js/>.
-<script src="https://unpkg.com/xtz@1.0.0-rc.1/xtz.min.js"></script>
-```
 
-```js
+## How was this built?
-var TZ = window.XTZ;
+
-```
+I live-streamed the creation of this entire project.
+
+If you'd like to learn how I did it and what challenges I encountered, you can watch here:
+https://www.youtube.com/playlist?list=PLxki0D-ilnqa6horOJ2G18WMZlJeQFlAt
+
+(though there have been a few minor updates and bug fixes off-camera)
 
 # API
 
--   `toTimeZone(utcDate, timeZone)`
+- `toLocalISOString(dateOrNull)`
--   `toTimeZoneISOString(isoString, timeZone)`
+- `toTimeZone(utcDate, timeZone)`
--   `toUTC(dtString, timeZone)`
+- `toTimeZoneISOString(isoString, timeZone)`
--   `toUTCISOString(dtString, timeZone)`
+- `fromTimeZone(dtString, timeZone)`
+- `toOffsetISOString(dtString, timeZone)`
 
 ## `toTimeZone(utcDate, timeZone)`
 
 > Convert UTC into a Target Time Zone
 
-Use ISO timestamps representing the absolute UTC time in the target time zone:
+Use ISO timestamps representing the absolute UTC time (ISO with or without offset):
 
 ```txt
 "2021-11-07T08:15:59.000Z"
 ```
 
-Convert directly to an ISO String:
+```js
+var utcDate = TZ.toTimeZone("2021-03-14T07:15:59.000Z", "America/New_York");
+// {
+//   year: 2021, month: 2, day: 14,
+//   hour: 3, minute: 15, second: 59, millisecond: 0,
+//   offset: -240, timeZoneName: "Eastern Daylight Time"
+// }
+
+utcDate.toISOString();
+// "2021-03-14T03:15:59.000-0400"
+// (same as "2021-11-07T07:15:59.000Z")
+```
+
+### Convert directly to an ISO String:
 
 ```js
 TZ.toTimeZoneISOString("2021-11-07T08:15:59.000Z", "America/New_York");
 // "2021-11-07T03:15:59.000-0500"
 ```
 
-Or use our bespoke (custom) date object:
+### Or use our bespoke (custom) date object:
 
 ```js
 var tzDate = TZ.toTimeZone("2021-11-07T08:15:59.000Z", "America/New_York");
 ```
 
-You can also use a date object with an absolute UTC time:
+### You can also use a date object with an absolute ISO time:
 
 ```js
 var tzDate = TZ.toTimeZone(
-    new Date("2021-11-07T08:15:59.000Z"),
+  new Date("2021-11-07T08:15:59.000Z"),
-    "America/New_York"
+  "America/New_York"
 );
 ```
 
@@ -124,42 +139,58 @@ console.log(tzDate.toISOString());
 // "2021-11-07T03:15:59.000-0500"
 ```
 
-Our ISO Strings + Offsets work with JavaScript's native Date object!!
+### Our ISO Strings + Offsets work with JavaScript's native Date object!!
 
 ```js
 new Date("2021-11-07T03:15:59.000-0500").toISOString());
 // "2021-11-07T08:15:59.000Z"
 ```
 
-## `toUTC(dtString, timeZone)`
+## `fromTimeZone(dtString, timeZone)`
 
-> Convert a Target Time Zone into UTC
+> Convert a Target Time Zone into ISO
 
 Use ISO-like timestamps representing the _local_ time in the target time zone:
 
 ```txt
-"2021-11-0 T03:15:59.000"
+"2021-11-0 03:15:59.000"
 ```
 
-Convert directly to an offset ISO String:
+```js
+var tzDate = TZ.fromTimeZone("2021-11-07 03:15:59.000", "America/New_York");
+// {
+//   year: 2021, month: 10, day: 7,
+//   hour: 3, minute: 15, second: 59, millisecond: 0,
+//   offset: -300, timeZoneName: "Eastern Standard Time"
+// }
+
+tzDate.toISOString();
+// "2021-11-07T03:15:59.000-0500"
+// (same as "2021-11-07T08:15:59.000Z")
+```
+
+### Convert directly to an offset ISO String:
 
 ```js
-TZ.toUTCISOString("2021-11-07 03:15:59.000", "America/New_York");
+TZ.toOffsetISOString("2021-11-07 03:15:59.000", "America/New_York");
 // "2021-11-07T03:15:59.000-0500"
 ```
 
-Or our bespoke date object:
+### Or our bespoke date object:
 
 ```js
-var utcDate = TZ.toUTC("2021-11-07 03:15:59.000", "America/New_York");
+var utcDate = TZ.fromTimeZone("2021-11-07 03:15:59.000", "America/New_York");
 ```
 
-You can also use a date object as the source time, but the date's UTC time will be treated as **_relative to time zone_** rather than absolute (this is a workaround for JavaScript's lack of bi-directional timezone support).
+### Use a Date as a source time
+
+You can also use a date object as the source time, but the date's UTC time will be treated as **_relative to time
+zone_** rather than absolute (this is a workaround for JavaScript's lack of bi-directional timezone support).
 
 ```js
-var utcDate = TZ.toUTC(
+var utcDate = TZ.fromTimeZone(
-    new Date("2021-11-07T03:15:59.000Z"),
+  new Date("2021-11-07T03:15:59.000Z"),
-    "America/New_York"
+  "America/New_York"
 );
 ```
 
@@ -172,30 +203,32 @@ utcDate.toISOString();
 
 > In 2021 Daylight Savings (in the US)
 >
-> -   begins at 2am on March 14th
+> - begins at 2am on March 14th (skips to 3am)
-> -   ends at 2am on November 7th
+> - ends at 2am on November 7th (resets to 1am)
 >
 > See <https://www.timeanddate.com/time/change/usa>.
 
 Q: What happens in March when 2am is skipped?
 
--   A: Although 2am is not a valid time, rather than throwing an error this library will resolve to 1am instead, which is an hour early in real ("tick-tock" or "monotonic") time.
+- A: Although 2am is not a valid time, rather than throwing an error this library will resolve to 1am instead, which
-    ```js
+  is an hour early in real ("tick-tock" or "monotonic") time.
-    var utcDate = TZ.toUTC("2021-03-14 02:15:59.000", "America/New_York");
+  ```js
-    utcDate.toISOString();
+  var utcDate = TZ.fromTimeZone("2021-03-14 02:15:59.000", "America/New_York");
-    // "2021-03-14T02:15:59.000-0400"
+  utcDate.toISOString();
-    // (same as "2021-03-14T01:15:59.000-0500")
+  // "2021-03-14T02:15:59.000-0400"
-    ```
+  // (same as "2021-03-14T01:15:59.000-0500")
+  ```
 
-Q: What happens in November when 2am happens twice?
+Q: What happens in November when 1am happens twice?
 
--   A: Although both 2ams are distinguishable with ISO offset times, only the first can be resolved from a local time with this library.
+- A: Although both 1ams are distinguishable with ISO offset times, only the first can be resolved from a local time
-    ```js
+  with this library.
-    var utcDate = TZ.toUTC("2021-11-07 01:15:59.000", "America/New_York");
+  ```js
-    utcDate.toISOString();
+  var utcDate = TZ.fromTimeZone("2021-11-07 01:15:59.000", "America/New_York");
-    // "2021-11-07T01:15:59.000-0400", same as "2021-11-07T05:15:59.000Z"
+  utcDate.toISOString();
-    // (an hour before the 2nd 2am at "2021-11-07T01:15:59.000-0500")
+  // "2021-11-07T01:15:59.000-0400", same as "2021-11-07T05:15:59.000Z"
-    ```
+  // (an hour before the 2nd 1am at "2021-11-07T01:15:59.000-0500")
+  ```
 
 # List of Time Zones
 
@@ -208,6 +241,7 @@ America/New_York    -0500
 America/Denver      -0700
 America/Phoenix     -0700 (No DST)
 America/Los_Angeles -0800
+UTC                 Z
 Australia/Adelaide  +0930 (30-min, has DST)
 Asia/Kathmandu      +0545 (No DST, 45-min)
 Asia/Kolkata        +0530 (No DST, 30-min)

examples.js

@@ -1,89 +1,81 @@
 var XTZ;
 
 (function () {
-    "use strict";
+  "use strict";
 
-    if (!XTZ) {
+  if (!XTZ) {
-        try {
+    try {
-            XTZ = require("xtz");
+      XTZ = require("xtz");
-        } catch (e) {
+    } catch (e) {
-            XTZ = require("./xtz.js");
+      XTZ = require("./xtz.js");
-        }
     }
+  }
 
-    var TZ = XTZ;
+  var TZ = XTZ;
-    var tzDate;
+  var tzDate;
 
-    //
+  //
-    // UTC-absolute time translated to a Time Zone
+  // UTC-absolute time translated to a Time Zone
-    //
+  //
-    function demo1() {
+  function demo1() {
-        console.info("What's the UTC equivalent of 8:15am in New York?");
+    console.info("What's the UTC equivalent of 8:15am in New York?");
-        console.info();
+    console.info();
 
-        console.info("\t// during daylight savings");
+    console.info("\t// during daylight savings");
-        console.info(
+    console.info(`\tXTZ.fromTimeZone("2021-03-14 08:15:59.000", "America/New_York")`);
-            `\tXTZ.toUTC("2021-03-14 08:15:59.000", "America/New_York")`
+    console.info(`\ttzDate.toISOString()`);
-        );
+    tzDate = XTZ.fromTimeZone("2021-03-14 08:15:59.000", "America/New_York");
-        console.info(`\ttzDate.toISOString()`);
+    console.info(
-        tzDate = XTZ.toUTC("2021-03-14 08:15:59.000", "America/New_York");
+      "\t" + tzDate.toISOString(),
-        console.info(
+      "// same as",
-            "\t" + tzDate.toISOString(),
+      new Date(tzDate.toISOString()).toISOString()
-            "// same as",
+    );
-            new Date(tzDate.toISOString()).toISOString()
+    console.info();
-        );
-        console.info();
 
-        console.info("\t// during standard time");
+    console.info("\t// during standard time");
-        console.info(
+    console.info(`\tXTZ.fromTimeZone("2021-11-07 08:15:59.000", "America/New_York")`);
-            `\tXTZ.toUTC("2021-11-07 08:15:59.000", "America/New_York")`
+    console.info(`\ttzDate.toISOString()`);
-        );
+    tzDate = XTZ.fromTimeZone("2021-11-07 08:15:59.000", "America/New_York");
-        console.info(`\ttzDate.toISOString()`);
+    console.info(
-        tzDate = XTZ.toUTC("2021-11-07 08:15:59.000", "America/New_York");
+      "\t" + tzDate.toISOString(),
-        console.info(
+      "// same as",
-            "\t" + tzDate.toISOString(),
+      new Date(tzDate.toISOString()).toISOString()
-            "// same as",
+    );
-            new Date(tzDate.toISOString()).toISOString()
+    console.info();
-        );
+  }
-        console.info();
-    }
 
-    //
+  //
-    // Time Zone-relative time translated to UTC
+  // Time Zone-relative time translated to UTC
-    //
+  //
-    function demo2() {
+  function demo2() {
-        console.info(
+    console.info("What time is it in New York at 8:15am on March 14th UTC?");
-            "What time is it in New York at 8:15am on March 14th UTC?"
+    console.info();
-        );
-        console.info();
 
-        console.info("\t// during daylight savings");
+    console.info("\t// during daylight savings");
-        console.info(
+    console.info(
-            `\tXTZ.toTimeZone("2021-03-14T08:15:59.000Z", "America/New_York")`
+      `\tXTZ.toTimeZone("2021-03-14T08:15:59.000Z", "America/New_York")`
-        );
+    );
-        console.info(`\ttzDate.toISOString()`);
+    console.info(`\ttzDate.toISOString()`);
-        tzDate = XTZ.toTimeZone("2021-03-14T08:15:59.000Z", "America/New_York");
+    tzDate = XTZ.toTimeZone("2021-03-14T08:15:59.000Z", "America/New_York");
-        console.info(
+    console.info(
-            "\t" + tzDate.toISOString(),
+      "\t" + tzDate.toISOString(),
-            "// same as",
+      "// same as",
-            new Date(tzDate.toISOString()).toISOString()
+      new Date(tzDate.toISOString()).toISOString()
-        );
+    );
-        console.info();
+    console.info();
 
-        console.info("\t// during standard time");
+    console.info("\t// during standard time");
-        console.info(
+    console.info(`\tXTZ.fromTimeZone("2021-11-07T08:15:59.000Z", "America/New_York")`);
-            `\tXTZ.toUTC("2021-11-07T08:15:59.000Z", "America/New_York")`
+    console.info(`\ttzDate.toISOString()`);
-        );
+    tzDate = XTZ.fromTimeZone("2021-11-07T08:15:59.000Z", "America/New_York");
-        console.info(`\ttzDate.toISOString()`);
+    console.info(
-        tzDate = XTZ.toUTC("2021-11-07T08:15:59.000Z", "America/New_York");
+      "\t" + tzDate.toISOString(),
-        console.info(
+      "// same as",
-            "\t" + tzDate.toISOString(),
+      new Date(tzDate.toISOString()).toISOString()
-            "// same as",
+    );
-            new Date(tzDate.toISOString()).toISOString()
+    console.info();
-        );
+  }
-        console.info();
-    }
 
-    demo1();
+  demo1();
-    demo2();
+  demo2();
 })();

index.html

@@ -0,0 +1,276 @@
+<!DOCTYPE html>
+<html lang="en" class="no-js">
+  <head>
+    <meta charset="UTF-8" />
+    <meta name="viewport" content="width=device-width" />
+
+    <title>Convert TimeZones in Your Browser</title>
+
+    <link rel="canonical" href="https://therootcompany.github.io/tz.js/" />
+
+    <meta name="theme-color" content="#FF00FF" />
+    <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/spcss@0.7.0" />
+
+    <style>
+      input {
+        width: 24em;
+      }
+    </style>
+  </head>
+
+  <body>
+    <!-- Content -->
+    <h1>
+      <a href="https://github.com/therootcompany/tz.js" target="_blank"
+        >XTZ.js</a
+      >
+    </h1>
+
+    <h3>
+      Current Time:
+      <br />
+      <span class="js-my-dt">YYYY-MM-DDThh:mm:ss.mmm+0000</span>
+    </h3>
+    <pre><code>new Intl.DateTimeFormat().resolvedOptions().timeZone;</code></pre>
+    Current Time Zone: <span class="js-my-tz">America/XXXX</span>
+    <br />
+    <pre><code>String(((new Date()).getTimezoneOffset() / 60)).padStart(2, '0') +
+String(((new Date()).getTimezoneOffset() % 60)).padStart(2, '0')</code></pre>
+    Current Time Offset: <span class="js-my-offset">-0000</span>
+    <hr />
+
+    <form class="js-tz2tz">
+      <h3>Convert Between Time Zones:</h3>
+      <label>
+        Time:
+        <input
+          class="js-dt-xtz"
+          type="text"
+          placeholder="ex: 2021-03-14 03:15:69.000"
+          required
+        />
+      </label>
+      <br />
+
+      <label>
+        Input Zone:
+        <input
+          class="js-tz1-xtz"
+          type="text"
+          placeholder="ex: UTC or America/New_York"
+          required
+        />
+      </label>
+      <br />
+
+      <label>
+        Output Zone:
+        <input
+          class="js-tz2-xtz"
+          type="text"
+          placeholder="ex: America/Los_Angeles or UTC"
+          required
+        />
+      </label>
+      <br />
+
+      <label>
+        ISO:
+        <input class="js-my-dt-xtz" type="text" disabled />
+      </label>
+      <br />
+      <br />
+      <button type="submit">Convert between Zones!</button>
+      <br />
+    </form>
+
+    <hr />
+
+    <form class="js-local">
+      <h3>Local ISO+Offset String:</h3>
+      <pre><code>XTZ.toLocalISOString(new Date())</code></pre>
+      <label>
+        ISO:
+        <input class="js-my-dt-local" type="text" disabled />
+      </label>
+      <br />
+    </form>
+
+    <hr />
+
+    <form class="js-tz2utc">
+      <h3>TimeZone-Relative (Local) to Absolute (ISO+Offset) String:</h3>
+      <pre><code>XTZ.fromTimeZone("<span class="js-dtx-tz">YYYY-03-14 03:15:69.000</span>", "<span class="js-tzx-tz">UTC</span>")
+   .toISOString()
+// <span class="js-myx-dt-tz"></span></code></pre>
+      <label>
+        Time:
+        <input
+          class="js-dt-tz"
+          type="text"
+          placeholder="ex: 2021-03-14 03:15:69.000"
+          required
+        />
+      </label>
+      <br />
+
+      <label>
+        Input Zone:
+        <input
+          class="js-tz-tz"
+          type="text"
+          placeholder="ex: America/New_York"
+          required
+        />
+      </label>
+      <br />
+      <label>
+        ISO:
+        <input class="js-my-dt-tz" type="text" disabled />
+      </label>
+      <br />
+      <br />
+      <button type="submit">Convert to ISO+Offset!</button>
+      <br />
+    </form>
+
+    <hr />
+
+    <form class="js-utc2tz">
+      <h3>Absolute (UTC) to TimeZone-Relative (ISO+Offset) String:</h3>
+      <pre><code>XTZ.toTimeZone("<span class="js-dtx-utc">YYYY-03-14 03:15:69.000</span>", "<span class="js-tzx-utc">UTC</span>")
+   .toISOString()
+// <span class="js-myx-dt-utc"></span></code></pre>
+      <label>
+        Time:
+        <input
+          class="js-dt-utc"
+          type="text"
+          placeholder="ex: 2021-03-14 03:15:69.000"
+          required
+        />
+      </label>
+      <br />
+      <label>
+        Output Zone:
+        <input
+          class="js-tz-utc"
+          type="text"
+          placeholder="ex: America/New_York"
+          required
+        />
+      </label>
+      <br />
+      <label>
+        ISO:
+        <input class="js-my-dt-utc" type="text" disabled />
+      </label>
+      <br />
+      <br />
+      <button type="submit">Convert to TZ!</button>
+      <br />
+    </form>
+
+    <hr />
+    <h3>Time Zones List</h3>
+    See the
+    <a href="https://en.wikipedia.org/wiki/List_of_tz_database_time_zones"
+      >Full List of Time Zones</a
+    >
+    on Wikipedia.
+    <pre>
+America/New_York    -0500 -0400             (Eastern Time)
+America/Denver      -0700 -0600             (Mountain Time)
+America/Phoenix     -0700 (No DST)          (Arizona Time)
+America/Los_Angeles -0800 -0700             (Pacific Time)
+UTC                 Z                       (UTC "Zulu" Time)
+Australia/Adelaide  +0930 +1030    (30-min)
+Asia/Kathmandu      +0545 (No DST) (45-min)
+Asia/Kolkata        +0530 (No DST) (30-min)</pre
+    >
+    <hr />
+    Code at
+    <a href="https://github.com/therootcompany/tz.js" target="_blank"
+      >github.com/therootcompany/tz.js</a
+    >
+    <script src="./xtz.js"></script>
+    <script src="./tolocalisostring.js"></script>
+    <script>
+      function $(sel, el) {
+        return (el || document.body).querySelector(sel);
+      }
+
+      function translate(dt, tz, tz2) {
+        var utc = new Date(XTZ.fromTimeZone(dt, tz).toISOString());
+        if (!tz2) {
+          return utc;
+        }
+        return XTZ.toTimeZone(utc, tz2);
+      }
+
+      function fromTimeZone() {
+        var curDt = $(".js-dt-tz").value;
+        var curTz = $(".js-tz-tz").value;
+        $(".js-my-dt-tz").value = XTZ.fromTimeZone(curDt, curTz).toISOString();
+
+        $(".js-dtx-tz").innerText = curDt;
+        $(".js-tzx-tz").innerText = curTz;
+        $(".js-myx-dt-tz").innerText = $(".js-my-dt-tz").value;
+      }
+
+      function toTZ() {
+        var curDt = $(".js-dt-utc").value;
+        var curTz = $(".js-tz-utc").value;
+        $(".js-my-dt-utc").value = XTZ.toTimeZone(curDt, curTz).toISOString();
+
+        $(".js-dtx-utc").innerText = curDt;
+        $(".js-tzx-utc").innerText = curTz;
+        $(".js-myx-dt-utc").innerText = $(".js-my-dt-utc").value;
+      }
+
+      function xTZ() {
+        var curDt = $(".js-dt-xtz").value;
+        var inTz = $(".js-tz1-xtz").value;
+        var outTz = $(".js-tz2-xtz").value;
+        $(".js-my-dt-xtz").value = translate(curDt, inTz, outTz).toISOString();
+      }
+
+      $(".js-my-dt-local").value = XTZ.toLocalISOString();
+
+      var myTz = new Intl.DateTimeFormat("default", {}).resolvedOptions()
+        .timeZone;
+      $(".js-my-tz").innerText = myTz;
+      $(".js-tz-tz").value = myTz;
+      $(".js-tz-utc").value = myTz;
+      $(".js-tz1-xtz").value = myTz;
+      $(".js-tz2-xtz").value = "Asia/Kathmandu";
+      var myOffset = -1 * new Date().getTimezoneOffset();
+      $(".js-my-offset").innerText =
+        XTZ.formatOffset(myOffset) + " (" + myOffset + ")";
+
+      var myDate = new Date();
+      $(".js-my-dt").innerText = XTZ.toTimeZone(myDate, myTz).toISOString();
+      $(".js-dt-tz").value = XTZ.toTimeZone(myDate, myTz)
+        .toISOString()
+        .replace("T", " ")
+        .replace(/(Z|(\+|-)\d+)$/, "");
+      $(".js-dt-xtz").value = $(".js-dt-tz").value;
+      $(".js-dt-utc").value = myDate.toISOString();
+
+      $("form.js-utc2tz").addEventListener("submit", function (ev) {
+        ev.preventDefault();
+        ev.stopPropagation();
+        toTZ();
+      });
+      $("form.js-tz2utc").addEventListener("submit", function (ev) {
+        ev.preventDefault();
+        ev.stopPropagation();
+        fromTimeZone();
+      });
+
+      fromTimeZone();
+      toTZ();
+      xTZ();
+    </script>
+  </body>
+</html>

package.json

@@ -1,10 +1,15 @@
 {
   "name": "xtz",
-  "version": "1.0.0",
+  "version": "1.3.2",
   "description": "A fast, lightweight, zero-dependency library to translate between Time Zones and UTC with native Intl.DateTimeFormat in ~100 LoC. For Node.js & Browsers.",
   "main": "xtz.js",
+  "files": [
+    "xtz.js",
+    "tolocalisostring.js"
+  ],
   "scripts": {
-    "test": "node ./test.js"
+    "test": "node ./test.js",
+    "build": "uglifyjs ./xtz.js > ./xtz.min.js ; gzip -k -f ./xtz.min.js"
   },
   "repository": {
     "type": "git",

test.js

@@ -3,314 +3,332 @@
 var TZ = require("./");
 
 function testUtcToTz(t) {
-    var result = TZ.toTimeZone.apply(TZ, t.inputs).toISOString();
+  var result = TZ.toTimeZone.apply(TZ, t.inputs).toISOString();
-    if (t.result !== result) {
+  var result2 = TZ.toTimeZoneISOString.apply(TZ, t.inputs);
-        throw new Error(
+  if (result !== result2 || t.result !== result) {
-            `Invalid UTC to TZ conversion for ${t.desc}:\n` +
+    throw new Error(
-                `\tExpected: ${t.result}\n` +
+      `Invalid UTC/ISO+Offset to TZ conversion for ${t.desc}:\n` +
-                `\tActual: ${result}\n`
+        `\tExpected: ${t.result}\n` +
-        );
+        `\tActual: ${result}\n`
-    }
+    );
+  }
 }
 
 function testTzToUtc(t) {
-    var result = TZ.toUTC.apply(TZ, t.inputs);
+  var result = TZ.fromTimeZone.apply(TZ, t.inputs).toISOString();
-    if (t.result !== result.toISOString()) {
+  var result2 = TZ.toOffsetISOString.apply(TZ, t.inputs);
-        console.log(result);
+  var result3 = TZ.toUTC.apply(TZ, t.inputs).toISOString();
-        throw new Error(
+  if (t.result !== result || t.result !== result2 || t.result !== result3) {
-            `Invalid TZ to UTC conversion for ${t.desc}:\n` +
+    console.error(result);
-                `\tExpected: ${t.result}\n` +
+    throw new Error(
-                `\tActual: ${result.toISOString()}\n`
+      `Invalid TZ to UTC conversion for ${t.desc}:\n` +
-        );
+        `\tExpected: ${t.result}\n` +
-    }
+        `\tActual: ${result.toISOString()}\n`
+    );
+  }
 }
 
 // At this real UTC time, what does the timezone translate it to?
 [
-    //
+  //
-    // Start-of-DST Tests
+  // Start-of-DST Tests
-    //
+  //
 
-    // [Start]
+  // [Start]
-    // What time is '2021-03-14 01:15:59.000 in New York' in UTC? // 2021-03-14 06:15:59.000
+  // What time is '2021-03-14 01:15:59.000 in New York' in UTC? // 2021-03-14 06:15:59.000
-    //                                                            // 2021-03-14T01:15:59.000-0500
+  //                                                            // 2021-03-14T01:15:59.000-0500
-    // What time is '2021-03-14 02:15:59.000 in New York' in UTC? // 2021-03-14 07:15:59.000
+  // What time is '2021-03-14 02:15:59.000 in New York' in UTC? // 2021-03-14 07:15:59.000
-    //                                                            // 2021-03-14T03:15:59.000-0400
+  //                                                            // 2021-03-14T03:15:59.000-0400
-    // What time is '2021-03-14 03:15:59.000 in New York' in UTC? // 2021-03-14 07:15:59.000
+  // What time is '2021-03-14 03:15:59.000 in New York' in UTC? // 2021-03-14 07:15:59.000
-    //                                                            // 2021-03-14T03:15:59.000-0400
+  //                                                            // 2021-03-14T03:15:59.000-0400
-    // What time is '2021-03-14 04:15:59.000 in New York' in UTC? // 2021-03-14 08:15:59.000
+  // What time is '2021-03-14 04:15:59.000 in New York' in UTC? // 2021-03-14 08:15:59.000
-    //                                                            // 2021-03-14T04:15:59.000-0400
+  //                                                            // 2021-03-14T04:15:59.000-0400
-    // [End]
+  // [End]
 
-    // 12:15am NY -0500 => -0400
+  // 12:15am NY -0500 => -0400
-    {
+  {
-        desc: "UTC to 12:15am NY EST",
+    desc: "UTC Zulu to 12:15am NY EST",
-        inputs: ["2021-03-14T05:15:59.000Z", "America/New_York"],
+    inputs: ["2021-03-14T05:15:59.000Z", "America/New_York"],
-        result: "2021-03-14T00:15:59.000-0500",
+    result: "2021-03-14T00:15:59.000-0500",
-    },
+  },
-    {
+  {
-        desc: "UTC to 12:15am NY EST (2)",
+    desc: "ISO+Offset to 12:15am NY EST (2)",
-        inputs: ["2021-03-14T00:15:59.000-0500", "America/New_York"],
+    inputs: ["2021-03-14T00:15:59.000-0500", "America/New_York"],
-        result: "2021-03-14T00:15:59.000-0500",
+    result: "2021-03-14T00:15:59.000-0500",
-    },
+  },
-    // 1:15am NY (non-DST)
+  // 1:15am NY (non-DST)
-    {
+  {
-        desc: "UTC to 1:15am NY EST",
+    desc: "UTC Zulu to 1:15am NY EST",
-        inputs: ["2021-03-14T06:15:59.000Z", "America/New_York"],
+    inputs: ["2021-03-14T06:15:59.000Z", "America/New_York"],
-        result: "2021-03-14T01:15:59.000-0500",
+    result: "2021-03-14T01:15:59.000-0500",
-    },
+  },
-    {
+  {
-        desc: "UTC to 1:15am NY EST (2)",
+    desc: "ISO+Offset to 1:15am NY EST (2)",
-        inputs: ["2021-03-14T01:15:59.000-0500", "America/New_York"],
+    inputs: ["2021-03-14T01:15:59.000-0500", "America/New_York"],
-        result: "2021-03-14T01:15:59.000-0500",
+    result: "2021-03-14T01:15:59.000-0500",
-    },
+  },
 
-    // NOTE: Can't 2:15am NY, because it does not exist (skipped by DST)
+  // NOTE: Can't 2:15am NY, because it does not exist (skipped by DST)
 
-    // 3:15am NY (DST)
+  // 3:15am NY (DST)
-    {
+  {
-        desc: "UTC to 3:15am NY EDT",
+    desc: "UTC Zulu to 3:15am NY EDT",
-        inputs: ["2021-03-14T07:15:59.000Z", "America/New_York"],
+    inputs: ["2021-03-14T07:15:59.000Z", "America/New_York"],
-        result: "2021-03-14T03:15:59.000-0400",
+    result: "2021-03-14T03:15:59.000-0400",
-    },
+  },
-    {
+  {
-        desc: "UTC to 3:15am NY EDT (2)",
+    desc: "ISO+Offset to 3:15am NY EDT (2)",
-        inputs: ["2021-03-14T03:15:59.000-0400", "America/New_York"],
+    inputs: ["2021-03-14T03:15:59.000-0400", "America/New_York"],
-        result: "2021-03-14T03:15:59.000-0400",
+    result: "2021-03-14T03:15:59.000-0400",
-    },
+  },
-    // 4:15am NY
+  // 4:15am NY
-    {
+  {
-        desc: "UTC to 4:15am NY EDT",
+    desc: "UTC Zulu to 4:15am NY EDT",
-        inputs: ["2021-03-14T08:15:59.000Z", "America/New_York"],
+    inputs: ["2021-03-14T08:15:59.000Z", "America/New_York"],
-        result: "2021-03-14T04:15:59.000-0400",
+    result: "2021-03-14T04:15:59.000-0400",
-    },
+  },
-    {
+  {
-        desc: "UTC to 4:15am NY EDT (2)",
+    desc: "ISO+Offset to 4:15am NY EDT (2)",
-        inputs: ["2021-03-14T04:15:59.000-0400", "America/New_York"],
+    inputs: ["2021-03-14T04:15:59.000-0400", "America/New_York"],
-        result: "2021-03-14T04:15:59.000-0400",
+    result: "2021-03-14T04:15:59.000-0400",
-    },
+  },
 
-    //
+  //
-    // End-of-DST Tests
+  // End-of-DST Tests
-    //
+  //
 
-    // [Start]
+  // [Start]
-    // What time is '2021-11-07 01:15:59.000 in New York' in UTC? // 2021-11-07 05:15:59.000
+  // What time is '2021-11-07 01:15:59.000 in New York' in UTC? // 2021-11-07 05:15:59.000
-    //                                                            // 2021-11-07T01:15:59.000-0400
+  //                                                            // 2021-11-07T01:15:59.000-0400
-    //                                                            // 2021-11-07 06:15:59.000
+  //                                                            // 2021-11-07 06:15:59.000
-    //                                                            // 2021-11-07T01:15:59.000-0500
+  //                                                            // 2021-11-07T01:15:59.000-0500
-    // What time is '2021-11-07 02:15:59.000 in New York' in UTC? // 2021-11-07 07:15:59.000
+  // What time is '2021-11-07 02:15:59.000 in New York' in UTC? // 2021-11-07 07:15:59.000
-    //                                                            // 2021-11-07T02:15:59.000-0500
+  //                                                            // 2021-11-07T02:15:59.000-0500
-    // What time is '2021-11-07 03:15:59.000 in New York' in UTC? // 2021-11-07 08:15:59.000
+  // What time is '2021-11-07 03:15:59.000 in New York' in UTC? // 2021-11-07 08:15:59.000
-    // [End]
+  // [End]
 
-    // 12:15am NY -0400 => -0500
+  // 12:15am NY -0400 => -0500
-    {
+  {
-        desc: "UTC to 2021 Nov 7, 12:15am NY EDT",
+    desc: "UTC Zulu to 2021 Nov 7, 12:15am NY EDT",
-        inputs: ["2021-11-07T04:15:59.000Z", "America/New_York"],
+    inputs: ["2021-11-07T04:15:59.000Z", "America/New_York"],
-        result: "2021-11-07T00:15:59.000-0400",
+    result: "2021-11-07T00:15:59.000-0400",
-    },
+  },
-    {
+  {
-        desc: "UTC to 2021 Nov 7, 12:15am NY EDT (2)",
+    desc: "ISO+Offset to 2021 Nov 7, 12:15am NY EDT (2)",
-        inputs: ["2021-11-07T00:15:59.000-0400", "America/New_York"],
+    inputs: ["2021-11-07T00:15:59.000-0400", "America/New_York"],
-        result: "2021-11-07T00:15:59.000-0400",
+    result: "2021-11-07T00:15:59.000-0400",
-    },
+  },
-    // 1:15am NY (DST) -0400
+  // 1:15am NY (DST) -0400
-    // NOTE: 1:15am happens TWICE (with different offsets)
+  // NOTE: 1:15am happens TWICE (with different offsets)
-    {
+  {
-        desc: "UTC to 2021 Nov 7, 1:15am NY EDT",
+    desc: "UTC Zulu to 2021 Nov 7, 1:15am NY EDT",
-        inputs: ["2021-11-07T05:15:59.000Z", "America/New_York"],
+    inputs: ["2021-11-07T05:15:59.000Z", "America/New_York"],
-        result: "2021-11-07T01:15:59.000-0400",
+    result: "2021-11-07T01:15:59.000-0400",
-    },
+  },
-    {
+  {
-        desc: "UTC to 2021 Nov 7, 1:15am NY EDT (2)",
+    desc: "ISO+Offset to 2021 Nov 7, 1:15am NY EDT (2)",
-        inputs: ["2021-11-07T01:15:59.000-0400", "America/New_York"],
+    inputs: ["2021-11-07T01:15:59.000-0400", "America/New_York"],
-        result: "2021-11-07T01:15:59.000-0400",
+    result: "2021-11-07T01:15:59.000-0400",
-    },
+  },
-    // 1:15am NY (non-DST) -0500
+  // 1:15am NY (non-DST) -0500
-    {
+  {
-        desc: "UTC to 2021 Nov 7, 1:15am NY EST",
+    desc: "UTC Zulu to 2021 Nov 7, 1:15am NY EST",
-        inputs: ["2021-11-07T06:15:59.000Z", "America/New_York"],
+    inputs: ["2021-11-07T06:15:59.000Z", "America/New_York"],
-        result: "2021-11-07T01:15:59.000-0500",
+    result: "2021-11-07T01:15:59.000-0500",
-    },
+  },
-    {
+  {
-        desc: "UTC to 2021 Nov 7, 1:15am NY EST (2)",
+    desc: "ISO+Offset to 2021 Nov 7, 1:15am NY EST (2)",
-        inputs: ["2021-11-07T01:15:59.000-0500", "America/New_York"],
+    inputs: ["2021-11-07T01:15:59.000-0500", "America/New_York"],
-        result: "2021-11-07T01:15:59.000-0500",
+    result: "2021-11-07T01:15:59.000-0500",
-    },
+  },
-    // 2:15am NY -0500
+  // 2:15am NY -0500
-    {
+  {
-        desc: "UTC to 2021 Nov 7, 2:15am NY EST",
+    desc: "UTC Zulu to 2021 Nov 7, 2:15am NY EST",
-        inputs: ["2021-11-07T07:15:59.000Z", "America/New_York"],
+    inputs: ["2021-11-07T07:15:59.000Z", "America/New_York"],
-        result: "2021-11-07T02:15:59.000-0500",
+    result: "2021-11-07T02:15:59.000-0500",
-    },
+  },
-    {
+  {
-        desc: "UTC to 2021 Nov 7, 2:15am NY EST (2)",
+    desc: "ISO+Offset to 2021 Nov 7, 2:15am NY EST (2)",
-        inputs: ["2021-11-07T02:15:59.000-0500", "America/New_York"],
+    inputs: ["2021-11-07T02:15:59.000-0500", "America/New_York"],
-        result: "2021-11-07T02:15:59.000-0500",
+    result: "2021-11-07T02:15:59.000-0500",
-    },
+  },
-    // 3:15am NY
+  // 3:15am NY
-    {
+  {
-        desc: "UTC to 2021 Nov 7, 3:15am NY EST",
+    desc: "UTC Zulu to 2021 Nov 7, 3:15am NY EST",
-        inputs: ["2021-11-07T08:15:59.000Z", "America/New_York"],
+    inputs: ["2021-11-07T08:15:59.000Z", "America/New_York"],
-        result: "2021-11-07T03:15:59.000-0500",
+    result: "2021-11-07T03:15:59.000-0500",
-    },
+  },
-    {
+  {
-        desc: "UTC to 2021 Nov 7, 3:15am NY EST (2)",
+    desc: "ISO+Offset to 2021 Nov 7, 3:15am NY EST (2)",
-        inputs: ["2021-11-07T03:15:59.000-0500", "America/New_York"],
+    inputs: ["2021-11-07T03:15:59.000-0500", "America/New_York"],
-        result: "2021-11-07T03:15:59.000-0500",
+    result: "2021-11-07T03:15:59.000-0500",
-    },
+  },
 
-    //
+  //
-    // Positive Offset Test
+  // Positive Offset Test
-    //
+  //
 
-    // Colombo +0530 (not DST)
+  // Colombo +0530 (not DST)
-    {
+  {
-        desc: "UTC to Asia/Colombo (1)",
+    desc: "UTC Zulu to Asia/Colombo (1)",
-        inputs: ["2021-03-14T08:15:59.000Z", "Asia/Colombo"],
+    inputs: ["2021-03-14T08:15:59.000Z", "Asia/Colombo"],
-        result: "2021-03-14T13:45:59.000+0530",
+    result: "2021-03-14T13:45:59.000+0530",
-    },
+  },
-    {
+  {
-        desc: "UTC to Asia/Colombo (2)",
+    desc: "ISO+Offset to Asia/Colombo (2)",
-        inputs: ["2021-03-14T13:45:59.000+0530", "Asia/Colombo"],
+    inputs: ["2021-03-14T13:45:59.000+0530", "Asia/Colombo"],
-        result: "2021-03-14T13:45:59.000+0530",
+    result: "2021-03-14T13:45:59.000+0530",
-    },
+  },
-    {
+  {
-        desc: "UTC to Asia/Colombo (3)",
+    desc: "UTC Zulu to Asia/Colombo (3)",
-        inputs: ["2021-11-07T08:15:59.000Z", "Asia/Colombo"],
+    inputs: ["2021-11-07T08:15:59.000Z", "Asia/Colombo"],
-        result: "2021-11-07T13:45:59.000+0530",
+    result: "2021-11-07T13:45:59.000+0530",
-    },
+  },
-    {
+  {
-        desc: "UTC to Asia/Colombo (4)",
+    desc: "ISO+Offset to Asia/Colombo (4)",
-        inputs: ["2021-11-07T13:45:59.000+0530", "Asia/Colombo"],
+    inputs: ["2021-11-07T13:45:59.000+0530", "Asia/Colombo"],
-        result: "2021-11-07T13:45:59.000+0530",
+    result: "2021-11-07T13:45:59.000+0530",
-    },
+  },
 ].forEach(testUtcToTz);
-console.info("Pass: UTC to TZ for America/New_York and Asia/Colombo");
+console.info(
+  "Pass: UTC/ISO+Offset to TZ for America/New_York and Asia/Colombo"
+);
 
 [
-    //
+  //
-    // Start-of-DST Tests
+  // Start-of-DST Tests
-    //
+  //
 
-    // [Start]
+  // [Start]
-    // What time is '2021-03-14 01:15:59.000 in New York' in UTC? // 2021-03-14 06:15:59.000
+  // What time is '2021-03-14 01:15:59.000 in New York' in UTC? // 2021-03-14 06:15:59.000
-    //                                                            // 2021-03-14T01:15:59.000-0500
+  //                                                            // 2021-03-14T01:15:59.000-0500
-    // What time is '2021-03-14 02:15:59.000 in New York' in UTC? // 2021-03-14 07:15:59.000
+  // What time is '2021-03-14 02:15:59.000 in New York' in UTC? // 2021-03-14 07:15:59.000
-    //                                                            // 2021-03-14T03:15:59.000-0400
+  //                                                            // 2021-03-14T03:15:59.000-0400
-    // What time is '2021-03-14 03:15:59.000 in New York' in UTC? // 2021-03-14 07:15:59.000
+  // What time is '2021-03-14 03:15:59.000 in New York' in UTC? // 2021-03-14 07:15:59.000
-    //                                                            // 2021-03-14T03:15:59.000-0400
+  //                                                            // 2021-03-14T03:15:59.000-0400
-    // What time is '2021-03-14 04:15:59.000 in New York' in UTC? // 2021-03-14 08:15:59.000
+  // What time is '2021-03-14 04:15:59.000 in New York' in UTC? // 2021-03-14 08:15:59.000
-    //                                                            // 2021-03-14T04:15:59.000-0400
+  //                                                            // 2021-03-14T04:15:59.000-0400
-    // [End]
+  // [End]
 
-    // 12:15am NY -0500 => -0400
+  // 12:15am NY -0500 => -0400
-    {
+  {
-        // 2021-03-14T05:15:59.000Z
+    // 2021-03-14T05:15:59.000Z
-        desc: "2021 Mar 14, 12:15am NY EST to UTC",
+    desc: "2021 Mar 14, 12:15am NY EST to UTC",
-        inputs: ["2021-03-14 00:15:59.000", "America/New_York"],
+    inputs: ["2021-03-14 00:15:59.000", "America/New_York"],
-        result: "2021-03-14T00:15:59.000-0500",
+    result: "2021-03-14T00:15:59.000-0500",
-    },
+  },
-    // 1:15am NY (non-DST)
+  // 1:15am NY (non-DST)
-    {
+  {
-        // 2021-03-14T06:15:59.000Z
+    // 2021-03-14T06:15:59.000Z
-        desc: "2021 Mar 14, 1:15am NY EST to UTC",
+    desc: "2021 Mar 14, 1:15am NY EST to UTC",
-        inputs: ["2021-03-14 01:15:59.000", "America/New_York"],
+    inputs: ["2021-03-14 01:15:59.000", "America/New_York"],
-        result: "2021-03-14T01:15:59.000-0500",
+    result: "2021-03-14T01:15:59.000-0500",
-    },
+  },
 
-    // NOTE: Can't 2:15am NY, because it does not exist (skipped by DST)
+  // NOTE: Can't 2:15am NY, because it does not exist (skipped by DST)
-    // This test is here to document the "undefined" behavior
+  // This test is here to document the "undefined" behavior
-    {
+  {
-        // Both 2021-03-14T06:15:59.000Z and 2021-03-14T07:15:59.000Z
+    // Both 2021-03-14T06:15:59.000Z and 2021-03-14T07:15:59.000Z
-        // would be reasonable substitutions, I think
+    // would be reasonable substitutions, I think
-        desc: "2021 Mar 14, 2:15am NY ExT to UTC",
+    desc: "2021 Mar 14, 2:15am NY ExT to UTC",
-        inputs: ["2021-03-14 02:15:59.000", "America/New_York"],
+    inputs: ["2021-03-14 02:15:59.000", "America/New_York"],
-        //result: "2021-03-14T01:15:59.000-0500", // 2021-03-14T06:15:59.000Z
+    //result: "2021-03-14T01:15:59.000-0500", // 2021-03-14T06:15:59.000Z
-        result: "2021-03-14T02:15:59.000-0400", // 2021-03-14T06:15:59.000Z
+    result: "2021-03-14T02:15:59.000-0400", // 2021-03-14T06:15:59.000Z
-        //result: "2021-03-14T02:15:59.000-0500", // 2021-03-14T07:15:59.000Z
+    //result: "2021-03-14T02:15:59.000-0500", // 2021-03-14T07:15:59.000Z
-    },
+  },
 
-    // 3:15am NY (DST)
+  // 3:15am NY (DST)
-    {
+  {
-        // 2021-03-14T07:15:59.000Z
+    // 2021-03-14T07:15:59.000Z
-        desc: "2021 Mar 14, 3:15am NY EDT to UTC",
+    desc: "2021 Mar 14, 3:15am NY EDT to UTC",
-        inputs: ["2021-03-14 03:15:59.000", "America/New_York"],
+    inputs: ["2021-03-14 03:15:59.000", "America/New_York"],
-        result: "2021-03-14T03:15:59.000-0400",
+    result: "2021-03-14T03:15:59.000-0400",
-    },
+  },
-    // 4:15am NY
+  // 4:15am NY
-    {
+  {
-        // 2021-03-14T08:15:59.000Z
+    // 2021-03-14T08:15:59.000Z
-        desc: "2021 Mar 14, 4:15am NY EDT to UTC",
+    desc: "2021 Mar 14, 4:15am NY EDT to UTC",
-        inputs: ["2021-03-14 04:15:59.000", "America/New_York"],
+    inputs: ["2021-03-14 04:15:59.000", "America/New_York"],
-        result: "2021-03-14T04:15:59.000-0400",
+    result: "2021-03-14T04:15:59.000-0400",
-    },
+  },
 
-    //
+  //
-    // End-of-DST Tests
+  // End-of-DST Tests
-    //
+  //
 
-    // [Start]
+  // [Start]
-    // What time is '2021-11-07 01:15:59.000 in New York' in UTC? // 2021-11-07 05:15:59.000
+  // What time is '2021-11-07 01:15:59.000 in New York' in UTC? // 2021-11-07 05:15:59.000
-    //                                                            // 2021-11-07T01:15:59.000-0400
+  //                                                            // 2021-11-07T01:15:59.000-0400
-    //                                                            // 2021-11-07 06:15:59.000
+  //                                                            // 2021-11-07 06:15:59.000
-    //                                                            // 2021-11-07T01:15:59.000-0500
+  //                                                            // 2021-11-07T01:15:59.000-0500
-    // What time is '2021-11-07 02:15:59.000 in New York' in UTC? // 2021-11-07 07:15:59.000
+  // What time is '2021-11-07 02:15:59.000 in New York' in UTC? // 2021-11-07 07:15:59.000
-    //                                                            // 2021-11-07T02:15:59.000-0500
+  //                                                            // 2021-11-07T02:15:59.000-0500
-    // What time is '2021-11-07 03:15:59.000 in New York' in UTC? // 2021-11-07 08:15:59.000
+  // What time is '2021-11-07 03:15:59.000 in New York' in UTC? // 2021-11-07 08:15:59.000
-    // [End]
+  // [End]
 
-    // 12:15am NY -0400 => -0500
+  // 12:15am NY -0400 => -0500
-    {
+  {
-        // 2021-11-07T04:15:59.000Z
+    // 2021-11-07T04:15:59.000Z
-        desc: "2021 Nov 7, 12:15am NY EDT to UTC",
+    desc: "2021 Nov 7, 12:15am NY EDT to UTC",
-        inputs: ["2021-11-07 00:15:59.000", "America/New_York"],
+    inputs: ["2021-11-07 00:15:59.000", "America/New_York"],
-        result: "2021-11-07T00:15:59.000-0400",
+    result: "2021-11-07T00:15:59.000-0400",
-    },
+  },
 
-    // 1:15am NY (DST) -0400
+  // 1:15am NY (DST) -0400
-    // NOTE: 1:15am happens TWICE (with different offsets), so we skip one
+  // NOTE: 1:15am happens TWICE (with different offsets), so we skip one
-    {
+  {
-        // ==> 2021-11-07T05:15:59.000Z
+    // ==> 2021-11-07T05:15:59.000Z
-        // [Skip] 2021-11-07T06:15:59.000Z
+    // [Skip] 2021-11-07T06:15:59.000Z
-        desc: "2021 Nov 7, 1:15am NY ExT to UTC",
+    desc: "2021 Nov 7, 1:15am NY ExT to UTC",
-        inputs: ["2021-11-07 01:15:59.000", "America/New_York"],
+    inputs: ["2021-11-07 01:15:59.000", "America/New_York"],
-        result: "2021-11-07T01:15:59.000-0400", // 2021-11-07T05:15:59.000Z
+    result: "2021-11-07T01:15:59.000-0400", // 2021-11-07T05:15:59.000Z
-        //result: "2021-11-07T01:15:59.000-0500", // 2021-11-07T06:15:59.000Z
+    //result: "2021-11-07T01:15:59.000-0500", // 2021-11-07T06:15:59.000Z
-    },
+  },
 
-    // 2:15am NY -0500
+  // 2:15am NY -0500
-    {
+  {
-        // 2021-11-07T07:15:59.000Z
+    // 2021-11-07T07:15:59.000Z
-        desc: "2021 Nov 7, 2:15am NY EST to UTC",
+    desc: "2021 Nov 7, 2:15am NY EST to UTC",
-        inputs: ["2021-11-07 02:15:59.000", "America/New_York"],
+    inputs: ["2021-11-07 02:15:59.000", "America/New_York"],
-        result: "2021-11-07T02:15:59.000-0500",
+    result: "2021-11-07T02:15:59.000-0500",
-    },
+  },
-    // 3:15am NY
+  // 3:15am NY
-    {
+  {
-        // 2021-11-07T08:15:59.000Z
+    // 2021-11-07T08:15:59.000Z
-        desc: "2021 Nov 7, 3:15am NY EST to UTC",
+    desc: "2021 Nov 7, 3:15am NY EST to UTC",
-        inputs: ["2021-11-07 03:15:59.000", "America/New_York"],
+    inputs: ["2021-11-07 03:15:59.000", "America/New_York"],
-        result: "2021-11-07T03:15:59.000-0500",
+    result: "2021-11-07T03:15:59.000-0500",
-    },
+  },
 
-    //
+  //
-    // Positive Offset Test
+  // Positive Offset Test
-    //
+  //
 
-    // Colombo +0530 (not DST)
+  // Colombo +0530 (not DST)
-    {
+  {
-        // 2021-03-14T08:15:59.000Z
+    // 2021-03-14T08:15:59.000Z
-        desc: "Asia/Colombo to UTC (1)",
+    desc: "Asia/Colombo to UTC (1)",
-        inputs: ["2021-03-14 13:45:59.000", "Asia/Colombo"],
+    inputs: ["2021-03-14 13:45:59.000", "Asia/Colombo"],
-        result: "2021-03-14T13:45:59.000+0530",
+    result: "2021-03-14T13:45:59.000+0530",
-    },
+  },
-    {
+  {
-        // 2021-03-14T08:15:59.000Z
+    // 2021-03-14T08:15:59.000Z
-        desc: "Asia/Colombo to UTC (2)",
+    desc: "Asia/Colombo to UTC (2)",
-        inputs: ["2021-11-07 13:45:59.000", "Asia/Colombo"],
+    inputs: ["2021-11-07 13:45:59.000", "Asia/Colombo"],
-        result: "2021-11-07T13:45:59.000+0530",
+    result: "2021-11-07T13:45:59.000+0530",
-    },
+  },
 ].forEach(testTzToUtc);
 console.info("Pass: TZ to UTC for America/New_York and Asia/Colombo");
+
+var localISOString = TZ.toLocalISOString();
+var reISOString = /^\d\d\d\d-\d\d-\d\dT\d\d:\d\d:\d\d\.\d\d\d[+-]\d\d\d\d$/;
+if (!reISOString.test(localISOString)) {
+  throw new Error("Couldn't get local time as iso+offset");
+}
+console.info("Pass: can get local time as ISO+Offset");
+
+var tzName = TZ.timeZone();
+if (!/^[A-Z]\w+\/[A-Z]\w+$/.test(tzName)) {
+  throw new Error("Couldn't get local Time Zone");
+}
+console.info("Pass: can get local timezone");

tolocalisostring.js

@@ -0,0 +1,50 @@
+(function (exports) {
+  "use strict";
+
+  // See <https://github.com/coolaj86/AJScript/issues/27>
+
+  function toLocalISOString(dateOrStr) {
+    var d;
+    if (dateOrStr) {
+      d = new Date(dateOrStr);
+    } else {
+      d = new Date();
+    }
+
+    var YYYY = d.getFullYear();
+    var MM = p2(d.getMonth() + 1);
+    var DD = p2(d.getDate());
+    var hh = p2(d.getHours());
+    var mm = p2(d.getMinutes());
+    var ss = p2(d.getSeconds());
+    var sss = d.getMilliseconds().toString().padStart(3, "0");
+
+    var offset = formatOffset(-d.getTimezoneOffset());
+
+    return `${YYYY}-${MM}-${DD}T${hh}:${mm}:${ss}.${sss}${offset}`;
+  }
+
+  function formatOffset(minutes) {
+    if (!minutes) {
+      return "Z";
+    }
+
+    var h = Math.floor(Math.abs(minutes) / 60);
+    var m = Math.abs(minutes) % 60;
+    var offset = "";
+    if (minutes > 0) {
+      offset = "+";
+    } else if (minutes < 0) {
+      offset = "-";
+    }
+
+    // +0500, -0730
+    return offset + p2(h) + p2(m);
+  }
+
+  function p2(x) {
+    return String(x).padStart(2, "0");
+  }
+
+  exports.toLocalISOString = toLocalISOString;
+})(("undefined" === typeof module && window) || exports);

xtz.js

@@ -1,182 +1,218 @@
-var XTZ;
+(function (exports) {
+  "use strict";
 
-(function () {
+  function toTimeZone(date, timeZone) {
-    "use strict";
+    // ISO string or existing date object
-
+    date = new Date(date);
-    function toTimeZone(date, timeZone) {
+    var options = {
-        // ISO string or existing date object
+      timeZone: timeZone,
-        date = new Date(date);
+      year: "numeric",
-        var options = {
+      month: "numeric",
-            timeZone: timeZone,
+      day: "numeric",
-            year: "numeric",
+      hour12: false,
-            month: "numeric",
+      hour: "numeric",
-            day: "numeric",
+      minute: "numeric",
-            hour12: false,
+      second: "numeric",
-            hour: "numeric",
+      fractionalSecondDigits: 3,
-            minute: "numeric",
-            second: "numeric",
-            fractionalSecondDigits: 3,
-        };
-
-        var tzOptions = Object.assign({ timeZoneName: "long" }, options);
-
-        // Every country uses the same year and months, right?
-        var formater = new Intl.DateTimeFormat("default", tzOptions);
-        var parts = formater.formatToParts(date);
-
-        var whole = {};
-        parts.forEach(function (part) {
-            var val = part.value;
-            switch (part.type) {
-                case "literal":
-                    // ignore separators and whitespace characters
-                    return;
-                case "timeZoneName":
-                    // keep as is - it's a string
-                    break;
-                case "month":
-                    // months are 0-indexed for new Date()
-                    val = parseInt(val, 10) - 1;
-                    break;
-                case "hour":
-                    // because sometimes 24 is used instead of 0, make 24 0
-                    val = parseInt(val, 10) % 24;
-                    break;
-                case "fractionalSecond":
-                    // fractionalSecond is a dumb name - should be millisecond
-                    whole.millisecond = parseInt(val, 10);
-                    return;
-                default:
-                    val = parseInt(val, 10);
-            }
-            // whole.month = 0;
-            whole[part.type] = val;
-        });
-
-        whole.timeZone = timeZone;
-        whole.offset = getOffset(date, whole);
-        whole.toISOString = _toOffsetISOString;
-        return whole;
-    }
-
-    function toTimeZoneISOString(date, timeZone) {
-        var whole = toTimeZone(date, timeZone);
-        return toOffsetISOString(whole);
-    }
-
-    function _toOffsetISOString() {
-        return toOffsetISOString(this);
-    }
-
-    function getOffset(utcDate, tzD2) {
-        var tzDate = new Date(toOffsetISOString(tzD2));
-        var diff =
-            Math.round(tzDate.valueOf() - utcDate.valueOf()) / (60 * 1000);
-        return diff;
-    }
-
-    function p2(x) {
-        return String(x).padStart(2, "0");
-    }
-
-    function p3(x) {
-        return String(x).padStart(3, "0");
-    }
-
-    function formatOffset(minutes) {
-        if (!minutes) {
-            return "Z";
-        }
-
-        var h = Math.floor(Math.abs(minutes) / 60);
-        var m = Math.abs(minutes) % 60;
-        var offset = "";
-        if (minutes > 0) {
-            offset = "+";
-        } else if (minutes < 0) {
-            offset = "-";
-        }
-
-        // +0500, -0730
-        return (
-            offset +
-            h.toString().padStart(2, "0") +
-            m.toString().padStart(2, "0")
-        );
-    }
-
-    function toOffsetISOString(d) {
-        var offset = formatOffset(d.offset);
-        return (
-            `${d.year}-${p2(d.month + 1)}-${p2(d.day)}` +
-            `T${p2(d.hour)}:${p2(d.minute)}:${p2(d.second)}.${p3(
-                d.millisecond
-            )}${offset}`
-        );
-    }
-
-    function toUTC(dt, tz) {
-        if ("string" === typeof dt) {
-            // Either of these formats should work:
-            // 2021-03-14 01:15:59
-            // 2021-03-14T01:15:59Z
-            dt = dt
-                .replace("T", " ")
-                .replace("Z", "")
-                .replace(" ", "T")
-                .replace(/$/, "Z");
-        }
-        var utcDate = new Date(dt);
-        var tzD2 = toTimeZone(utcDate, tz);
-        var offset = tzD2.offset;
-        tzD2.offset = "";
-
-        var deltaDate = new Date(utcDate);
-        deltaDate.setUTCMinutes(deltaDate.getUTCMinutes() - offset);
-        var tzD3 = toTimeZone(deltaDate, tz);
-
-        if (
-            tzD3.hour === utcDate.getUTCHours() &&
-            tzD3.minute === utcDate.getUTCMinutes()
-        ) {
-            return tzD3;
-        }
-
-        var diff = tzD3.offset - offset;
-        var h = Math.floor(Math.abs(diff) / 60);
-        var m = Math.abs(diff) % 60;
-        var sign = Math.abs(diff) / diff;
-        tzD3.hour -= h * sign;
-        tzD3.minute -= m * sign;
-
-        return tzD3;
-    }
-
-    function toUTCISOString(date, timeZone) {
-        var whole = toUTC(date, timeZone);
-        return toOffsetISOString(whole);
-    }
-
-    XTZ = {
-        // bespoke date =>
-        // 2021-11-07T3:15:59-0500
-        toOffsetISOString: toOffsetISOString,
-
-        // -240 => -0400
-        formatOffset: formatOffset,
-
-        // [ "2021-11-07T08:15:59Z", "America/New_York" ]
-        // => "2021-11-07T03:15:59-0500" // 2021-11-07 03:15:59
-        toTimeZone: toTimeZone,
-        toTimeZoneISOString: toTimeZoneISOString,
-
-        // [ "2021-11-07 03:15:59", "America/New_York" ]
-        // => "2021-11-07T03:15:59-0500" // 2021-11-07T08:15:59Z
-        toUTC: toUTC,
-        toUTCISOString: toUTCISOString,
     };
 
-    if ("undefined" != typeof module && module.exports) {
+    var tzOptions = Object.assign({ timeZoneName: "long" }, options);
-        module.exports = XTZ;
+
+    // Every country uses the same year and months, right?
+    var formater = new Intl.DateTimeFormat("default", tzOptions);
+    var parts = formater.formatToParts(date);
+
+    // millisecond is explicitly 0 for iOS' lack of fractionalSecond support
+    var whole = { millisecond: 0 };
+    parts.forEach(function (part) {
+      var val = part.value;
+      switch (part.type) {
+        case "literal":
+          // ignore separators and whitespace characters
+          return;
+        case "timeZoneName":
+          // keep as is - it's a string
+          break;
+        case "month":
+          // months are 0-indexed for new Date()
+          val = parseInt(val, 10) - 1;
+          break;
+        case "hour":
+          // because sometimes 24 is used instead of 0, make 24 0
+          val = parseInt(val, 10) % 24;
+          break;
+        case "fractionalSecond":
+          // fractionalSecond is a dumb name - should be millisecond
+          whole.millisecond = parseInt(val, 10);
+          return;
+        default:
+          val = parseInt(val, 10);
+      }
+      // ex: whole.month = 0;
+      whole[part.type] = val;
+    });
+
+    whole.timeZone = timeZone;
+    whole.offset = getOffset(date, whole);
+    whole.toISOString = _toOffsetISOString;
+    return whole;
+  }
+
+  function toTimeZoneISOString(date, timeZone) {
+    var whole = toTimeZone(date, timeZone);
+    return formatAsOffsetISOString(whole);
+  }
+
+  function _toOffsetISOString() {
+    /* jshint validthis: true */
+    return formatAsOffsetISOString(this);
+  }
+
+  function getOffset(utcDate, tzD2) {
+    var tzDate = new Date(formatAsOffsetISOString(tzD2));
+    var diff = Math.round((tzDate.valueOf() - utcDate.valueOf()) / (60 * 1000));
+    return diff;
+  }
+
+  function p2(x) {
+    return String(x).padStart(2, "0");
+  }
+
+  function p3(x) {
+    return String(x).padStart(3, "0");
+  }
+
+  function formatOffset(minutes) {
+    if (!minutes) {
+      return "Z";
     }
-}());
+
+    var h = Math.floor(Math.abs(minutes) / 60);
+    var m = Math.abs(minutes) % 60;
+    var offset = "";
+    if (minutes > 0) {
+      offset = "+";
+    } else if (minutes < 0) {
+      offset = "-";
+    }
+
+    // +0500, -0730
+    return (
+      offset + h.toString().padStart(2, "0") + m.toString().padStart(2, "0")
+    );
+  }
+
+  function toOffsetISOString(date, timeZone) {
+    if ("object" === typeof date && "offset" in date && "year" in date) {
+      return formatAsOffsetISOString(date);
+    }
+
+    var whole = fromTimeZone(date, timeZone);
+    return formatAsOffsetISOString(whole);
+  }
+
+  function formatAsOffsetISOString(d) {
+    var offset = formatOffset(d.offset);
+    return (
+      `${d.year}-${p2(d.month + 1)}-${p2(d.day)}` +
+      `T${p2(d.hour)}:${p2(d.minute)}:${p2(d.second)}.${p3(
+        d.millisecond
+      )}${offset}`
+    );
+  }
+
+  function fromTimeZone(dt, tz) {
+    if ("string" === typeof dt) {
+      // Either of these formats should work:
+      // 2021-03-14 01:15:59
+      // 2021-03-14T01:15:59Z
+      dt = dt
+        .replace("T", " ")
+        .replace("Z", "")
+        .replace(" ", "T")
+        .replace(/$/, "Z");
+    }
+    var utcDate = new Date(dt);
+    var tzD2 = toTimeZone(utcDate, tz);
+    var offset = tzD2.offset;
+    tzD2.offset = 0;
+
+    var deltaDate = new Date(utcDate);
+    deltaDate.setUTCMinutes(deltaDate.getUTCMinutes() - offset);
+    var tzD3 = toTimeZone(deltaDate, tz);
+
+    if (
+      tzD3.hour === utcDate.getUTCHours() &&
+      tzD3.minute === utcDate.getUTCMinutes()
+    ) {
+      return tzD3;
+    }
+
+    var diff = tzD3.offset - offset;
+    var h = Math.floor(Math.abs(diff) / 60);
+    var m = Math.abs(diff) % 60;
+    var sign = Math.abs(diff) / diff;
+    tzD3.hour -= h * sign;
+    tzD3.minute -= m * sign;
+
+    return tzD3;
+  }
+
+  function toLocalISOString(dateOrStr) {
+    var d;
+    if (dateOrStr) {
+      d = new Date(dateOrStr);
+    } else {
+      d = new Date();
+    }
+
+    var YYYY = d.getFullYear();
+    var MM = p2(d.getMonth() + 1);
+    var DD = p2(d.getDate());
+    var hh = p2(d.getHours());
+    var mm = p2(d.getMinutes());
+    var ss = p2(d.getSeconds());
+    var sss = d.getMilliseconds().toString().padStart(3, "0");
+
+    var offset = formatOffset(-d.getTimezoneOffset());
+
+    return `${YYYY}-${MM}-${DD}T${hh}:${mm}:${ss}.${sss}${offset}`;
+  }
+
+  function getTimeZone() {
+    return new Intl.DateTimeFormat().resolvedOptions().timeZone;
+  }
+
+  exports.XTZ = {
+    // bespoke date =>
+    // 2021-11-07T3:15:59-0500
+    // (todo?)
+    // xtzToISOString: formatAsOffsetISOString,
+    // (deprecated)
+    toOffsetISOString: toOffsetISOString,
+
+    // -240 => -0400
+    formatOffset: formatOffset,
+
+    // "America/New_York"
+    timeZone: getTimeZone,
+    // "2021-11-07T03:15:59-0500"
+    toLocalISOString: toLocalISOString,
+
+    // [ "2021-11-07T08:15:59Z", "America/New_York" ]
+    // => "2021-11-07T03:15:59-0500" // 2021-11-07 03:15:59
+    toTimeZone: toTimeZone,
+    toTimeZoneISOString: toTimeZoneISOString,
+
+    // [ "2021-11-07 03:15:59", "America/New_York" ]
+    // => "2021-11-07T03:15:59-0500" // 2021-11-07T08:15:59Z
+    toUTC: fromTimeZone,
+    fromTimeZone: fromTimeZone,
+    // deprecated
+    toUTCISOString: toOffsetISOString,
+  };
+
+  if ("undefined" != typeof module && module.exports) {
+    module.exports = exports.XTZ;
+  }
+})(("undefined" === typeof module && window) || exports);

xtz.min.js

@@ -1 +1 @@
-var XTZ;(function(){"use strict";function toTimeZone(date,timeZone){date=new Date(date);var options={timeZone:timeZone,year:"numeric",month:"numeric",day:"numeric",hour12:false,hour:"numeric",minute:"numeric",second:"numeric",fractionalSecondDigits:3};var tzOptions=Object.assign({timeZoneName:"long"},options);var formater=new Intl.DateTimeFormat("default",tzOptions);var parts=formater.formatToParts(date);var whole={};parts.forEach(function(part){var val=part.value;switch(part.type){case"literal":return;case"timeZoneName":break;case"month":val=parseInt(val,10)-1;break;case"hour":val=parseInt(val,10)%24;break;case"fractionalSecond":whole.millisecond=parseInt(val,10);return;default:val=parseInt(val,10)}whole[part.type]=val});whole.timeZone=timeZone;whole.offset=getOffset(date,whole);whole.toISOString=_toOffsetISOString;return whole}function toTimeZoneISOString(date,timeZone){var whole=toTimeZone(date,timeZone);return toOffsetISOString(whole)}function _toOffsetISOString(){return toOffsetISOString(this)}function getOffset(utcDate,tzD2){var tzDate=new Date(toOffsetISOString(tzD2));var diff=Math.round(tzDate.valueOf()-utcDate.valueOf())/(60*1e3);return diff}function p2(x){return String(x).padStart(2,"0")}function p3(x){return String(x).padStart(3,"0")}function formatOffset(minutes){if(!minutes){return"Z"}var h=Math.floor(Math.abs(minutes)/60);var m=Math.abs(minutes)%60;var offset="";if(minutes>0){offset="+"}else if(minutes<0){offset="-"}return offset+h.toString().padStart(2,"0")+m.toString().padStart(2,"0")}function toOffsetISOString(d){var offset=formatOffset(d.offset);return`${d.year}-${p2(d.month+1)}-${p2(d.day)}`+`T${p2(d.hour)}:${p2(d.minute)}:${p2(d.second)}.${p3(d.millisecond)}${offset}`}function toUTC(dt,tz){if("string"===typeof dt){dt=dt.replace("T"," ").replace("Z","").replace(" ","T").replace(/$/,"Z")}var utcDate=new Date(dt);var tzD2=toTimeZone(utcDate,tz);var offset=tzD2.offset;tzD2.offset="";var deltaDate=new Date(utcDate);deltaDate.setUTCMinutes(deltaDate.getUTCMinutes()-offset);var tzD3=toTimeZone(deltaDate,tz);if(tzD3.hour===utcDate.getUTCHours()&&tzD3.minute===utcDate.getUTCMinutes()){return tzD3}var diff=tzD3.offset-offset;var h=Math.floor(Math.abs(diff)/60);var m=Math.abs(diff)%60;var sign=Math.abs(diff)/diff;tzD3.hour-=h*sign;tzD3.minute-=m*sign;return tzD3}function toUTCISOString(date,timeZone){var whole=toUTC(date,timeZone);return toOffsetISOString(whole)}XTZ={toOffsetISOString:toOffsetISOString,formatOffset:formatOffset,toTimeZone:toTimeZone,toTimeZoneISOString:toTimeZoneISOString,toUTC:toUTC,toUTCISOString:toUTCISOString};if("undefined"!=typeof module&&module.exports){module.exports=XTZ}})();
+var XTZ;(function(){"use strict";function toTimeZone(date,timeZone){date=new Date(date);var options={timeZone:timeZone,year:"numeric",month:"numeric",day:"numeric",hour12:false,hour:"numeric",minute:"numeric",second:"numeric",fractionalSecondDigits:3};var tzOptions=Object.assign({timeZoneName:"long"},options);var formater=new Intl.DateTimeFormat("default",tzOptions);var parts=formater.formatToParts(date);var whole={millisecond:0};parts.forEach(function(part){var val=part.value;switch(part.type){case"literal":return;case"timeZoneName":break;case"month":val=parseInt(val,10)-1;break;case"hour":val=parseInt(val,10)%24;break;case"fractionalSecond":whole.millisecond=parseInt(val,10);return;default:val=parseInt(val,10)}whole[part.type]=val});whole.timeZone=timeZone;whole.offset=getOffset(date,whole);whole.toISOString=_toOffsetISOString;return whole}function toTimeZoneISOString(date,timeZone){var whole=toTimeZone(date,timeZone);return toOffsetISOString(whole)}function _toOffsetISOString(){return toOffsetISOString(this)}function getOffset(utcDate,tzD2){var tzDate=new Date(toOffsetISOString(tzD2));var diff=Math.round((tzDate.valueOf()-utcDate.valueOf())/(60*1e3));return diff}function p2(x){return String(x).padStart(2,"0")}function p3(x){return String(x).padStart(3,"0")}function formatOffset(minutes){if(!minutes){return"Z"}var h=Math.floor(Math.abs(minutes)/60);var m=Math.abs(minutes)%60;var offset="";if(minutes>0){offset="+"}else if(minutes<0){offset="-"}return offset+h.toString().padStart(2,"0")+m.toString().padStart(2,"0")}function toOffsetISOString(d){var offset=formatOffset(d.offset);return`${d.year}-${p2(d.month+1)}-${p2(d.day)}`+`T${p2(d.hour)}:${p2(d.minute)}:${p2(d.second)}.${p3(d.millisecond)}${offset}`}function toUTC(dt,tz){if("string"===typeof dt){dt=dt.replace("T"," ").replace("Z","").replace(" ","T").replace(/$/,"Z")}var utcDate=new Date(dt);var tzD2=toTimeZone(utcDate,tz);var offset=tzD2.offset;tzD2.offset=0;var deltaDate=new Date(utcDate);deltaDate.setUTCMinutes(deltaDate.getUTCMinutes()-offset);var tzD3=toTimeZone(deltaDate,tz);if(tzD3.hour===utcDate.getUTCHours()&&tzD3.minute===utcDate.getUTCMinutes()){return tzD3}var diff=tzD3.offset-offset;var h=Math.floor(Math.abs(diff)/60);var m=Math.abs(diff)%60;var sign=Math.abs(diff)/diff;tzD3.hour-=h*sign;tzD3.minute-=m*sign;return tzD3}function toUTCISOString(date,timeZone){var whole=toUTC(date,timeZone);return toOffsetISOString(whole)}XTZ={toOffsetISOString:toOffsetISOString,formatOffset:formatOffset,toTimeZone:toTimeZone,toTimeZoneISOString:toTimeZoneISOString,toUTC:toUTC,toUTCISOString:toUTCISOString};if("undefined"!=typeof module&&module.exports){module.exports=XTZ}})();