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Parsing with Unix Timestamp tokens (X/x) and other visual tokens in strict mode results in Invalid Date

See original GitHub issue

Describe the bug When X/x token is used and there are visual/escaped tokens in strict mode you get Invalid Date, best described with this code snippet and log result:

source:

const dayjs = require('dayjs');
dayjs.extend(require('dayjs/plugin/customParseFormat'))
dayjs.extend(require('dayjs/plugin/advancedFormat'))

console.log(
  [
    [ 'now format',
      () => dayjs().format('x'),
      () => dayjs().format('X'),
    ],

    [ 'x',
      () => dayjs('/Date(1623787200000)/', '/[Date](x)/').format('/[Date](x)/'),
      () => dayjs('/1623787200000/', '/X/').format('/[Date](X)/'),
      () => dayjs('--1623787200000--', '--X--').format('/[Date](X)/'),
      () => dayjs('1623787200000', 'x').format('x'),
      () => dayjs('1623787200000', 'x').format('YYYY-MM-DD'),
    ],

    [ 'X',
      () => dayjs('/Date(1623787200)/', '/[Date](X)/').format('/[Date](X)/'),
      () => dayjs('/1623787200/', '/X/').format('/[Date](X)/'),
      () => dayjs('--1623787200--', '--X--').format('/[Date](X)/'),
      () => dayjs('1623787200', 'X').format('X'),
      () => dayjs('1623787200', 'X').format('YYYY-MM-DD'),
    ],

    [ 'x STRICT',
      () => dayjs('/Date(1623787200000)/', '/[Date](x)/', true).format('/[Date](x)/'),
      () => dayjs('/1623787200000/', '/x/', true).format('/[Date](x)/'),
      () => dayjs('--1623787200000--', '--x--', true).format('/[Date](x)/'),
      () => dayjs('1623787200000', 'x', true).format('x'),
      () => dayjs('1623787200000', 'x', true).format('YYYY-MM-DD'),
    ],

    [ 'X STRICT',
      () => dayjs('/Date(1623787200)/', '/[Date](X)/', true).format('/[Date](X)/'),
      () => dayjs('/1623787200/', '/X/', true).format('/[Date](X)/'),
      () => dayjs('--1623787200--', '--X--', true).format('/[Date](X)/'),
      () => dayjs('1623787200', 'X', true).format('X'),
      () => dayjs('1623787200', 'X', true).format('YYYY-MM-DD'),
    ],
  ]
    .map(
      ([name, ...cases]) =>
        '\n// ' +
        name +
        '\n' +
        cases.map((f) => `${f.toString().substring(6)} // ${f()}`).join('\n')
    )
    .join('\n')
);

output:

// now format
dayjs().format('x') // 1625563406782
dayjs().format('X') // 1625563406

// x
dayjs('/Date(1623787200000)/', '/[Date](x)/').format('/[Date](x)/') // /Date(1625515200000)/
dayjs('/1623787200000/', '/X/').format('/[Date](X)/') // /Date(1625515200)/
dayjs('--1623787200000--', '--X--').format('/[Date](X)/') // /Date(1625515200)/
dayjs('1623787200000', 'x').format('x') // 1623787200000
dayjs('1623787200000', 'x').format('YYYY-MM-DD') // 2021-06-16

// X
dayjs('/Date(1623787200)/', '/[Date](X)/').format('/[Date](X)/') // /Date(1625515200)/
dayjs('/1623787200/', '/X/').format('/[Date](X)/') // /Date(1625515200)/
dayjs('--1623787200--', '--X--').format('/[Date](X)/') // /Date(1625515200)/
dayjs('1623787200', 'X').format('X') // 1623787200
dayjs('1623787200', 'X').format('YYYY-MM-DD') // 2021-06-16

// x STRICT
dayjs('/Date(1623787200000)/', '/[Date](x)/', true).format('/[Date](x)/') // Invalid Date
dayjs('/1623787200000/', '/x/', true).format('/[Date](x)/') // Invalid Date
dayjs('--1623787200000--', '--x--', true).format('/[Date](x)/') // Invalid Date
dayjs('1623787200000', 'x', true).format('x') // 1623787200000
dayjs('1623787200000', 'x', true).format('YYYY-MM-DD') // 2021-06-16

// X STRICT
dayjs('/Date(1623787200)/', '/[Date](X)/', true).format('/[Date](X)/') // Invalid Date
dayjs('/1623787200/', '/X/', true).format('/[Date](X)/') // Invalid Date
dayjs('--1623787200--', '--X--', true).format('/[Date](X)/') // Invalid Date
dayjs('1623787200', 'X', true).format('X') // 1623787200
dayjs('1623787200', 'X', true).format('YYYY-MM-DD') // 2021-06-16

Expected behavior not to get Invalid Date

Information