Add Latin locale

[tukusejssirs]

For romcal, I need to add Latin locale to dayjs. Therefore I have some questions regarding this.

---

1. As Latin weekday names are composed mostly of two words (like feria secunda for Monday), should I use a command as follows?

weekdays: 'Dominica-feria secunda-feria tertia-feria quarta-feria quinta-feria sexta-Sabbato'.split('-'),

---

2. There’s a subissue: in Latin, there are two different ways to name the weekdays, and a third one (e.g. used in the Roman Catholic Church) which modifies one of the former two:

A. using dies (used in the Ancient Rome):

• dies Solis;
• dies Lunae;
• dies Martis;
• dies Mercurii;
• dies Iovis;
• dies Veneris;
• dies Saturni;

B. using ferias (numbering days, starting with 1 for Sunday):

• feria prima;
• feria secunda;
• feria tertia;
• feria quarta;
• feria quinta;
• feria sexta;
• feria septima;

C. variation of the feria names, used in the RC Church (uses Dominica for Sunday and Sabbato for Saturday):

• Dominica;
• feria secunda;
• feria tertia;
• feria quarta;
• feria quinta;
• feria sexta;
• Sabbato.

Now, I need the C one only, but some other people might like some other names. If I implement this, I’d like to be as thorough as possible, so my question is: should I create three separate regions (like la-va for Vatican, i.e. the 3rd type of weekday names)? Or how else should I fix this?

---

3. Weekday names: when the feria names are used, one may shorten it by using Roman numerals (e.g. feria sexta → fera VI). I presume I should use these in weekdaysShort, but I need a confirmation. Seldom, simply the Roman numerals are used (like IV), for which I could use weekdaysMin.

---

4. Another thing is that in Latin, they don’t use Arabic numeral, instead they always use Roman numerals (for days of month, year, weekday numbers). I suggest to use Arabic numerals in time format (I don’t think that in Ancient Rome, they used time format at all and nowadays, I believe they use Arabic numerals for time instead). But how do I output Roman numerals? Does dayjs include such a converter? Should I create a custom function within la.js?

---

5. As I know that you compare the output of dayjs with the output of Moment in dayjs tests, is it required to create la.js locale in Moment first?

[iamkun]

1. it's perfectly ok to use normal Array [].
2. It's up to you cause you are a native speaker. One locale or three locales will both be fine.
3. It's ok.
4. I don't really understand. Can you detail it, please?
5. There's no need, just add our own in the first place.

We use ISO 639-2 country code.
Check lists short codes for language here. https://en.wikipedia.org/wiki/List_of_ISO_639-2_codes

[tukusejssirs]

2. Okay, then if I’ll go the route of having three locales, how does the locale inheritance work? I don’t want to define common locale parts in all three locales.

3. Okay.

4. Okay, I’ll do my best.

Arabic numerals = 1, 2, 3, … Roman numerals = I, II, III, IV, …

Date example: XX Iunii MMXX = 20 June 2020

Time format would 24h in Arabic numerals, e.g. 13:24.

Now, my question is about the conversion from Arabic numerals to Roman numerals: is there a builtin converter or should I create a function within the locale? If I need to create a function and I create it in the main, la.js locale, will it be inherited (i.e. defined) in the ‘sublocales’ like la-va.js?

---

6. Country and lang codes. la is code for Latin according to ISO 369-2. However, I believe that country code system you use is ISO 3166-1 alpha-2, which assigns VA for Vatican / the Holy See.

[iamkun]

2 the best way might just be simple copy-paste.

Yes, you have to create a function to make the conversion in locale file.

[tukusejssirs]

I have created the la.js locale. I isn’t perfect, as currently the relativeTime format uses Nominative case only (and thus ad %d anni [in %d years] is grammatically incorrect, but %d anni [%d years] is correct). Is there a way to check within the locale what is the context of the queried value? I think there is none, but without that I can’t see a way to return the correct form of the words. I wish there would be a way (like extra argument added to dayjs when invoking, as this would be other languages too (and then I could fix moment/moment#5408 (read this comment to get the main issue).

---

Anyway, as there is no la.js in Moment, should I create a test that would check if the output matches a fixed string?

---

I wanted to test the locale locally, but with my limited knowledge I could not make it work. This is what I have done:

1. Run npm install && npm run-script build.
2. In the repo root, I created a file called testLa.js with the following content:

const dayjs = require('./dayjs.min.js');
dayjs.locale('la')

var l = dayjs.locale()

console.log(l)

3. Run the script (node testLa.js) and I have expected the output to be la, but it was en.

Now, I have read the docs, but adding require('dayjs/locale/la') throwed the following error:

$ node testLa.js 
internal/modules/cjs/loader.js:960
  throw err;
  ^

Error: Cannot find module 'dayjs/locale/la'
Require stack:
- /home/ts/git/c10n/dayjs/testLa.js
    at Function.Module._resolveFilename (internal/modules/cjs/loader.js:957:15)
    at Function.Module._load (internal/modules/cjs/loader.js:840:27)
    at Module.require (internal/modules/cjs/loader.js:1019:19)
    at require (internal/modules/cjs/helpers.js:77:18)
    at Object.<anonymous> (/home/ts/git/c10n/dayjs/testLa.js:2:1)
    at Module._compile (internal/modules/cjs/loader.js:1133:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1153:10)
    at Module.load (internal/modules/cjs/loader.js:977:32)
    at Function.Module._load (internal/modules/cjs/loader.js:877:14)
    at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:74:12) {
  code: 'MODULE_NOT_FOUND',
  requireStack: [ '/home/ts/git/c10n/dayjs/testLa.js' ]
}

I understand that the module was not found, but even if I change the path to src/locale/la, it won’t find anything.

---

Anyway, I’ve just create a PR, but it definately needs to be reviewed.

[tukusejssirs]

Sorry, I was busy lately. Could you help me with running dayjs from terminal using directly the code in the src/ folder? That way I could double-check if all tests pass more easily. Thanks for you help.

[iamkun]

I would manually change 'dayjs/locale/la' to '../src/locale/la' 😢

[tukusejssirs]

I would manually change 'dayjs/locale/la' to '../src/locale/la' cry

Where would you do that?

[iamkun]

I would manually change 'dayjs/locale/la' to '../src/locale/la' cry

Where would you do that?

to replace this Error: Cannot find module 'dayjs/locale/la'

[tukusejssirs]

I have tried out your suggestion, but it still does not work, see below. All my scripts are located in the repo root.

node testLa2.js (with require)

Script contents:

const dayjs = require('./dayjs.min.js')
require('./src/locale/la')
dayjs.locale('la')

var l = dayjs.locale()

console.log(l)

Error output:

$ node testLa2.js 
/home/ts/git/c10n/dayjs/src/locale/la.js:2
import dayjs from 'dayjs'
^^^^^^

SyntaxError: Cannot use import statement outside a module
    at wrapSafe (internal/modules/cjs/loader.js:1053:16)
    at Module._compile (internal/modules/cjs/loader.js:1101:27)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1157:10)
    at Module.load (internal/modules/cjs/loader.js:985:32)
    at Function.Module._load (internal/modules/cjs/loader.js:878:14)
    at Module.require (internal/modules/cjs/loader.js:1025:19)
    at require (internal/modules/cjs/helpers.js:72:18)
    at Object.<anonymous> (/home/ts/git/c10n/dayjs/testLa2.js:2:1)
    at Module._compile (internal/modules/cjs/loader.js:1137:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1157:10)

node testLa2.mjs (with require)

Script contents:

const dayjs = require('./dayjs.min.js')
require('./src/locale/la')
dayjs.locale('la')

var l = dayjs.locale()

console.log(l)

Error output:

$ node testLa2.mjs 
(node:275906) ExperimentalWarning: The ESM module loader is experimental.
file:///home/ts/git/c10n/dayjs/testLa2.mjs:1
const dayjs = require('./dayjs.min.js')
              ^

ReferenceError: require is not defined
    at file:///home/ts/git/c10n/dayjs/testLa2.mjs:1:15
    at ModuleJob.run (internal/modules/esm/module_job.js:139:37)
    at async Loader.import (internal/modules/esm/loader.js:179:24)

node testLa2.js (with import)

Script contents:

import dayjs from './dayjs.min.js'
import './src/locale/la'
dayjs.locale('la')

var l = dayjs.locale()

console.log(l)

Error output:

$ node testLa2.js 
(node:278457) Warning: To load an ES module, set "type": "module" in the package.json or use the .mjs extension.
/home/ts/git/c10n/dayjs/testLa2.js:1
import dayjs from './dayjs.min.js'
^^^^^^

SyntaxError: Cannot use import statement outside a module
    at wrapSafe (internal/modules/cjs/loader.js:1053:16)
    at Module._compile (internal/modules/cjs/loader.js:1101:27)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1157:10)
    at Module.load (internal/modules/cjs/loader.js:985:32)
    at Function.Module._load (internal/modules/cjs/loader.js:878:14)
    at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:71:12)
    at internal/main/run_main_module.js:17:47

node testLa2.mjs (with import)

Script contents:

import dayjs from './dayjs.min.js'
import './src/locale/la'
dayjs.locale('la')

var l = dayjs.locale()

console.log(l)

Error output:

$ node testLa2.mjs 
(node:279861) ExperimentalWarning: The ESM module loader is experimental.
internal/modules/run_main.js:54
    internalBinding('errors').triggerUncaughtException(
                              ^

Error [ERR_MODULE_NOT_FOUND]: Cannot find module '/home/ts/git/c10n/dayjs/src/locale/la' imported from /home/ts/git/c10n/dayjs/testLa2.mjs
Did you mean to import ../src/locale/la.js?
    at finalizeResolution (internal/modules/esm/resolve.js:259:11)
    at moduleResolve (internal/modules/esm/resolve.js:636:10)
    at Loader.defaultResolve [as _resolve] (internal/modules/esm/resolve.js:726:11)
    at Loader.resolve (internal/modules/esm/loader.js:97:40)
    at Loader.getModuleJob (internal/modules/esm/loader.js:243:28)
    at ModuleWrap.<anonymous> (internal/modules/esm/module_job.js:47:40)
    at link (internal/modules/esm/module_job.js:46:36) {
  code: 'ERR_MODULE_NOT_FOUND'
}

[iamkun]

please use npm test to test the source code

[tukusejssirs]

Indeed, you’re right, there are failing tests, but I did not change anything in those files.

Failing tests

Summary of all failing tests
 FAIL  test/parse.test.js
  ● Parse › moment-js like formatted dates

    expect(received).toBe(expected) // Object.is equality
    
    Expected value to be:
      "2018-01-01T00:00:00+01:00"
    Received:
      "2018-01-01T01:00:00+01:00"

      37 |     expect(dayjs(d).valueOf()).toBe(moment(d).valueOf()) // not recommend
      38 |     d = '2018'
    > 39 |     expect(dayjs(d).format()).toBe(moment(d).format()) // not recommend
      40 |     d = '2018-05-02T11:12:13Z' // should go direct to new Date() rather our regex
      41 |     expect(dayjs(d).format()).toBe(moment(d).format()) // not recommend
      42 |   })
      
      at Object.<anonymous> (test/parse.test.js:39:31)

 FAIL  test/plugin/utc-utcOffset.test.js
  ● change hours when changing the utc offset in UTC mode

    expect(received).toBe(expected) // Object.is equality
    
    Expected value to be:
      5
    Received:
      4

      70 |   expect(d.hour()).toBe(6)
      71 |   expect(d.utcOffset(0).hour()).toBe(6)
    > 72 |   expect(d.utcOffset(-60).hour()).toBe(5)
      73 |   expect(d.utcOffset(60).hour()).toBe(7)
      74 |   expect(d.utcOffset(-30).format('HH:mm')).toBe('06:01')
      75 |   expect(d.utcOffset(30).format('HH:mm')).toBe('07:01')
      
      at Object.<anonymous> (test/plugin/utc-utcOffset.test.js:72:35)

  ● keep hours when adding month in offset mode

    expect(received).toBe(expected) // Object.is equality
    
    Expected value to be:
      6
    Received:
      5

      94 |   const dm8 = dayjs('2000-01-30T06:31:00-08:00').utcOffset(-8)
      95 | 
    > 96 |   expect(d10.add(1, 'month').hour()).toBe(6)
      97 |   expect(dm8.add(1, 'month').hour()).toBe(6)
      98 | 
      99 |   expect(d10.add(-2, 'month').hour()).toBe(6)
      
      at Object.<anonymous> (test/plugin/utc-utcOffset.test.js:96:38)

 FAIL  test/plugin/calendar.test.js
  ● No argument && null && undefined

    TypeError: Cannot convert undefined or null to object
        at hasOwnProperty (<anonymous>)

      17 | it('No argument && null && undefined', () => {
      18 |   expect(dayjs().calendar()).toEqual(moment().calendar())
    > 19 |   expect(dayjs().calendar(null)).toEqual(moment().calendar(null))
      20 |   expect(dayjs().calendar(undefined)).toEqual(moment().calendar(undefined))
      21 | })
      22 | 
      
      at hasOwnProp (node_modules/moment/moment.js:42:48)
      at isMomentInputObject (node_modules/moment/moment.js:3669:44)
      at isMomentInput (node_modules/moment/moment.js:3629:13)
      at Moment.calendar (node_modules/moment/moment.js:3729:17)
      at Object.<anonymous> (test/plugin/calendar.test.js:19:51)


Test Suites: 3 failed, 52 passed, 55 total
Tests:       4 failed, 505 passed, 509 total
Snapshots:   0 total
Time:        27.64s
Ran all test suites.
npm ERR! Test failed.  See above for more details.

[iamkun]

All of our tests should be passed. You can submit a pull request with any change and test with our CI to see if there is an environmental issue.

[tukusejssirs]

I’ve no idea how to fix those errors, but somehow it uses GMT+1 timezone instead of UTC.

Note that I use CET (winter timezone; GMT+1) and CEST (summer timezone; GMT+2) locally; although it should not be connected, it might be.