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1/**
2 * @name parseJSON
3 * @category Common Helpers
4 * @summary Parse a JSON date string
5 *
6 * @description
7 * Converts a complete ISO date string in UTC time, the typical format for transmitting
8 * a date in JSON, to a JavaScript `Date` instance.
9 *
10 * This is a minimal implementation for converting dates retrieved from a JSON API to
11 * a `Date` instance which can be used with other functions in the `date-fns` library.
12 * The following formats are supported:
13 *
14 * - `2000-03-15T05:20:10.123Z`: The output of `.toISOString()` and `JSON.stringify(new Date())`
15 * - `2000-03-15T05:20:10Z`: Without milliseconds
16 * - `2000-03-15T05:20:10+00:00`: With a zero offset, the default JSON encoded format in some other languages
17 * - `2000-03-15T05:20:10+05:45`: With a positive or negative offset, the default JSON encoded format in some other languages
18 * - `2000-03-15T05:20:10+0000`: With a zero offset without a colon
19 * - `2000-03-15T05:20:10`: Without a trailing 'Z' symbol
20 * - `2000-03-15T05:20:10.1234567`: Up to 7 digits in milliseconds field. Only first 3 are taken into account since JS does not allow fractional milliseconds
21 * - `2000-03-15 05:20:10`: With a space instead of a 'T' separator for APIs returning a SQL date without reformatting
22 *
23 * For convenience and ease of use these other input types are also supported
24 * via [toDate](https://date-fns.org/docs/toDate):
25 *
26 * - A `Date` instance will be cloned
27 * - A `number` will be treated as a timestamp
28 *
29 * Any other input type or invalid date strings will return an `Invalid Date`.
30 *
31 * @param dateStr - A fully formed ISO8601 date string to convert
32 *
33 * @returns The parsed date in the local time zone
34 */
35export function parseJSON(dateStr) {
36 const parts = dateStr.match(
37 /(\d{4})-(\d{2})-(\d{2})[T ](\d{2}):(\d{2}):(\d{2})(?:\.(\d{0,7}))?(?:Z|(.)(\d{2}):?(\d{2})?)?/,
38 );
39 if (parts) {
40 // Group 8 matches the sign
41 return new Date(
42 Date.UTC(
43 +parts[1],
44 +parts[2] - 1,
45 +parts[3],
46 +parts[4] - (+parts[9] || 0) * (parts[8] == "-" ? -1 : 1),
47 +parts[5] - (+parts[10] || 0) * (parts[8] == "-" ? -1 : 1),
48 +parts[6],
49 +((parts[7] || "0") + "00").substring(0, 3),
50 ),
51 );
52 }
53 return new Date(NaN);
54}
55
56// Fallback for modularized imports:
57export default parseJSON;