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durasjdurasj
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Add check for etc zone support before use (#918)
1 parent da04179 commit 88eae19

2 files changed

Lines changed: 15 additions & 4 deletions

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‎src/impl/locale.js‎

Lines changed: 9 additions & 4 deletions
Original file line numberDiff line numberDiff line change
@@ -3,6 +3,7 @@ import * as English from "./english.js";
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import Settings from "../settings.js";
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import DateTime from "../datetime.js";
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import Formatter from "./formatter.js";
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import IANAZone from "../zones/IANAZone.js";
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let intlDTCache = {};
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function getCachedDTF(locString, opts = {}) {
@@ -185,11 +186,15 @@ class PolyDateFormatter {
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if (dt.zone.universal && this.hasIntl) {
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// UTC-8 or Etc/UTC-8 are not part of tzdata, only Etc/GMT+8 and the like.
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// That is why fixed-offset TZ is set to that unless it is:
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// 1. Outside of the supported range Etc/GMT-14 to Etc/GMT+12.
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// 2. Not a whole hour, e.g. UTC+4:30.
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// 1. Representing offset 0 when UTC is used to maintain previous behavior and does not become GMT.
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// 2. Unsupported by the browser:
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// - some do not support Etc/
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// - < Etc/GMT-14, > Etc/GMT+12, and 30-minute or 45-minute offsets are not part of tzdata
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const gmtOffset = -1 * (dt.offset / 60);
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if (gmtOffset >= -14 && gmtOffset <= 12 && gmtOffset % 1 === 0) {
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z = gmtOffset >= 0 ? `Etc/GMT+${gmtOffset}` : `Etc/GMT${gmtOffset}`;
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const offsetZ = gmtOffset >= 0 ? `Etc/GMT+${gmtOffset}` : `Etc/GMT${gmtOffset}`;
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const isOffsetZoneSupported = IANAZone.isValidZone(offsetZ);
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if (dt.offset !== 0 && isOffsetZoneSupported) {
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z = offsetZ;
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this.dt = dt;
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} else {
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// Not all fixed-offset zones like Etc/+4:30 are present in tzdata.

‎test/datetime/format.test.js‎

Lines changed: 6 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -333,6 +333,12 @@ test("DateTime#toLocaleString() shows things in the right fixed-offset zone when
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);
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});
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test("DateTime#toLocaleString() shows things with UTC if fixed-offset zone with 0 offset is used", () => {
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expect(dt.setZone("UTC").toLocaleString(DateTime.DATETIME_FULL)).toBe(
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"May 25, 1982, 9:23 AM UTC"
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);
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});
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test("DateTime#toLocaleString() does the best it can with unsupported fixed-offset zone when showing the zone", () => {
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expect(dt.setZone("UTC+4:30").toLocaleString(DateTime.DATETIME_FULL)).toBe(
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"May 25, 1982, 9:23 AM UTC"

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