3.9 KiB
v2 Upgrade Guide
Common changes
Camel case naming schema
Function submodules now use camelCase naming schema:
// 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 for more details.
String arguments
Functions now don't accept strings as arguments. Strings should
be parsed using parseISO (ISO 8601) or parse.
See this post for more details.
// 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
Dateare converted toDateusing date-fns'toDatefunction; - arguments expected to be numbers are converted to integer numbers using our custom
toIntegerimplementation (see #765); - arguments expected to be strings are converted to strings using JavaScript's
Stringfunction; - arguments expected to be booleans are converted to boolean using JavaScript's
Booleanfunction.
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:
falsefor functions that return booleans (expectisValid);Invalid Datefor functions that return dates;NaNfor functions that return numbers;- and
String('Invalid Date')for functions that return strings.
See tests and PRs #460 and #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 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.
Locales renamed:
en→en-USzh_cn→zh-CNzh_tw→zh-TW
// Before v2.0.0
import locale from 'date-fns/locale/zh_cn'
// v2.0.0 onward
import locale from 'date-fns/locale/zh-CN'