date-fns / date-fns-upgrade

A tool for upgrading date-fns versions

date-fns upgrade

Support package with helper functions for date-fns upgrade from 1.x to 2.x

Codemod that will help you apply these helpers automatically located here - date-fns-upgrade-codemod.

Installation

npm install @date-fns/upgrade --save
# or with yarn
yarn add @date-fns/upgrade

Usage

convertTokens

convertTokens is a helper function used for 2nd argument of format function to convert date tokens like YYYY to new format. See this post for more details.

+import { convertTokens } from '@date-fns/upgrade/v2'

const formattedDate = format(
  new Date(),
- 'YYYY',
+ convertTokens('YYYY'),
)

legacyParse

[email protected] functions don't accept string as arguments any more (see CHANGELOG), legacyParse is used to simplify that transition, it uses algorithm from 1.x to do that. See this post for details on "why" this was done.

+import { legacyParse } from '@date-fns/upgrade/v2'

const formattedDate = format(
- '2014',
+ legacyParse('2014'),
  'YYYY',
)

legacyParseMap

legacyParseMap is used same as legacyParse but for arguments that accept arrays.

+import { legacyParseMap } from '@date-fns/upgrade/v2'

var dateToCompare = new Date(2015, 8, 6)
var datesArray = [
  '2014-01-01',
  '2015-01-01'
]
-var result = closestIndexTo(dateToCompare, datesArray)
+var result = closestIndexTo(dateToCompare, legacyParseMap(datesArray))

License

MIT © Sasha Koss

date-fns-upgrade's Issues

TypeError: isDate_1.default is not a function

When try to follow the example.:

+import { legacyParse } from '@date-fns/upgrade/v2'

const formattedDate = format(
- '2014',
+ legacyParse('2014'),
  'YYYY',
)

The following error occurs
TypeError: isDate_1.default is not a function
If I remove .default from the if (isDate_1.default(argument)) {, it will work.

Bundle Size: not tree shakable, date-fns not peer dependency

When used with date-fns 2.0, the entire package is imported and prevents tree shaking. Can we allow tree shaking within date-fns-upgrade and include date-fns as a peer dependency instead of direct dependency?

Browser support: why is this library compiled to ES6?

It seems like an unnecessary cutoff in browser support (e.g. IE doesn't support arrow functions).

Warning about missing sourcemap when using webpack5

Hi,

I'm wondering if it would be possible to add

"inlineSources": true,

to tsconfig.json file?

It won't affect source code at all but will satisfy webpack5 complaints about source map files, however, it will increase the size of source maps.

Currently, bundling the following code:

import { convertTokens } from '@date-fns/upgrade/v2/convertTokens';

...

produces this warning:

WARNING in ./node_modules/@date-fns/upgrade/v2/convertTokens/index.js
Module Warning (from ./node_modules/source-map-loader/dist/cjs.js):
Failed to parse source map from '/Users/owrobel/projects/webpack-demo/node_modules/@date-fns/src/v2/convertTokens/index.ts' file: Error: ENOENT: no such file or directory, open '/Users/owrobel/projects/webpack-demo/node_modules/@date-fns/src/v2/convertTokens/index.ts'
 @ ./src/index.js 1:0-67 3:12-25