DiskStorage destination folder check for when the destination is passed as a function.

[AbhilakshSinghReen]

The 'DiskStorage' function in 'storage\disk.js' will now check if the destination folder exists on the disk or not. Earlier this check was only being performed when the destination was passed as a string, not when the destination was passed as a function. Changes have also been made to throw a type error if the destination is a type other than a function or a string.

[mriedem]

The README should be updated:

https://github.com/expressjs/multer/blob/master/README.md#diskstorage

Note: You are responsible for creating the directory when providing destination as a function.

[LinusU]

I'm not sure if we would be able to release this in 1.x since I think it's a breaking change?

And in 2.x we have removed DiskStorage 😅

[AbhilakshSinghReen]

Okay. No problem. Thanks for the update.

I'm not sure if we would be able to release this in 1.x since I think it's a breaking change?

And in 2.x we have removed DiskStorage 😅