Error when using composer require-dev.mikey179/vfsStream is invalid

Question

I am using Amazon LightSail and the CodeIgniter framework. Trying to install PhpSpreadsheet - https://phpspreadsheet.readthedocs.io/en/latest/#installation using

composer require phpoffice/phpspreadsheet

However I then am greeted with

 [RuntimeException]
  require-dev.mikey179/vfsStream is invalid, it should not contain uppercase characters. Please use mikey179/vfsstream instead.

I did the usual Googling but couldn't find anything specific.

When I run

composer.phar show

I get the error from above.

Canvasback

which php version are you installing onto? – Lactation

also check this: github.com/bovigo/vfsStream/issues/173 – Lactation

Please share more details about the current state of your composer.json. Also, which version of Composer are you using? – Boucicault

How do I find out the version? Every command I try and run, it fails with that error. I'm on Amazon LightSail... – Canvasback

Answer 1

You must have mikey179/vfsStream in your composer.json in require-dev section (as the problem is for require-dev and you are trying to do normal require).

Simply change the name of package to all lowercase characters.

Aircraft

Answer 2

Just replace mikey179/vfsStream with mikey179/vfsstream

they need to be in lowercase

Reheat

This has already been pointed out in several other answers. – Workbag

Answer 3

Make this "mikey179/vfsStream" package name to lowercase.

"mikey179/vfsStream" replace this to "mikey179/vfsstream"

Bloodroot

Answer 4

In your composer.json file look for mikey179/vfsStream and lowercase all its characters and make it mikey179/vfsstream

"require-dev": {
    "mikey179/vfsstream": "1.1.*",
    "phpunit/phpunit": "4.* || 5.*"
}

Rubenrubens