119 lines
4.1 KiB
Markdown
119 lines
4.1 KiB
Markdown
# v2 Upgrade Guide
|
|
|
|
## Common changes
|
|
|
|
This page covers a few of the most common problems people face when updating from v1 to v2. For a more detailed list of changes, look at the [change log for version 2.0.0](https://date-fns.org/docs/Change-Log).
|
|
|
|
### Camel case naming schema
|
|
|
|
Function submodules now use camelCase naming schema:
|
|
|
|
```javascript
|
|
// Before v2.0.0
|
|
import differenceInCalendarISOYears from 'date-fns/difference_in_calendar_iso_years'
|
|
|
|
// v2.0.0 onward
|
|
import differenceInCalendarISOYears from 'date-fns/differenceInCalendarISOYears'
|
|
```
|
|
|
|
### New formatting tokens
|
|
|
|
Starting with v2 `format` and `parse` uses [Unicode tokens].
|
|
|
|
See [Unicode Tokens doc](https://date-fns.org/docs/Unicode-Tokens) for more details.
|
|
|
|
### String arguments
|
|
|
|
Functions now don't accept strings as date arguments. Strings should
|
|
be parsed using `parseISO` (ISO 8601) or `parse`.
|
|
|
|
See [this post](https://blog.date-fns.org/post/we-cut-date-fns-v2-minimal-build-size-down-to-300-bytes-and-now-its-the-smallest-date-library-18f2nvh2z0yal) for more details.
|
|
|
|
```javascript
|
|
// Before v2.0.0
|
|
addDays('2016-01-01', 1)
|
|
|
|
// v2.0.0 onward
|
|
addDays(parseISO('2016-01-01'), 1)
|
|
```
|
|
|
|
### Arguments conversion
|
|
|
|
All functions now implicitly convert arguments by following rules:
|
|
|
|
| | date | number | string | boolean |
|
|
| --------- | ------------ | ------ | ----------- | ------- |
|
|
| 0 | new Date(0) | 0 | '0' | false |
|
|
| '0' | Invalid Date | 0 | '0' | false |
|
|
| 1 | new Date(1) | 1 | '1' | true |
|
|
| '1' | Invalid Date | 1 | '1' | true |
|
|
| true | Invalid Date | NaN | 'true' | true |
|
|
| false | Invalid Date | NaN | 'false' | false |
|
|
| null | Invalid Date | NaN | 'null' | false |
|
|
| undefined | Invalid Date | NaN | 'undefined' | false |
|
|
| NaN | Invalid Date | NaN | 'NaN' | false |
|
|
|
|
Notes:
|
|
|
|
- as before, arguments expected to be `Date` are converted to `Date` using _date-fns'_ `toDate` function;
|
|
- arguments expected to be numbers are converted to integer numbers using our custom `toInteger` implementation
|
|
(see [#765](https://github.com/date-fns/date-fns/pull/765));
|
|
- arguments expected to be strings are converted to strings using JavaScript's `String` function;
|
|
- arguments expected to be booleans are converted to boolean using JavaScript's `Boolean` function.
|
|
|
|
`null` and `undefined` passed to optional arguments (i.e. properties of `options` argument)
|
|
are ignored as if no argument was passed.
|
|
|
|
If any argument is invalid (i.e. `NaN` for numbers and `Invalid Date` for dates),
|
|
an invalid value will be returned:
|
|
|
|
- `false` for functions that return booleans (expect `isValid`);
|
|
- `Invalid Date` for functions that return dates;
|
|
- `NaN` for functions that return numbers;
|
|
- and `String('Invalid Date')` for functions that return strings.
|
|
|
|
See tests and PRs [#460](https://github.com/date-fns/date-fns/pull/460) and
|
|
[#765](https://github.com/date-fns/date-fns/pull/765) for exact behavior.
|
|
|
|
### `null`
|
|
|
|
`null` now is not a valid date. `isValid(null)` returns `false`;
|
|
`toDate(null)` returns an invalid date. Since `toDate` is used internally
|
|
by all the functions, operations over `null` will also return an invalid date.
|
|
[See #537](https://github.com/date-fns/date-fns/issues/537) for the reasoning.
|
|
|
|
### `RangeError`
|
|
|
|
Functions now throw `RangeError` if optional values passed to `options`
|
|
are not `undefined` or have expected values.
|
|
This change is introduced for consistency with ECMAScript standard library which does the same.
|
|
|
|
### `TypeError`
|
|
|
|
All functions now check if the passed number of arguments is less
|
|
than the number of required arguments and throw `TypeError` exception if so.
|
|
|
|
### UMD/CDN
|
|
|
|
The Bower & UMD/CDN package versions are no longer supported.
|
|
|
|
### New locale format
|
|
|
|
See [docs/Locale](https://date-fns.org/docs/Locale).
|
|
|
|
Locales renamed:
|
|
|
|
- `en` → `en-US`
|
|
- `zh_cn` → `zh-CN`
|
|
- `zh_tw` → `zh-TW`
|
|
|
|
```javascript
|
|
// Before v2.0.0
|
|
import locale from 'date-fns/locale/zh_cn'
|
|
|
|
// v2.0.0 onward
|
|
import locale from 'date-fns/locale/zh-CN'
|
|
```
|
|
|
|
[unicode tokens]: https://www.unicode.org/reports/tr35/tr35-dates.html#Date_Field_Symbol_Table
|