Magento2: [Regression] Static content deploy is not possible when one of themes have no static assets

[Igloczek]

It's exactly same issue as #7411, confirmed by few others in comments.

It makes deployment not possible, even for built-in languages like en_US, while we have a theme without something in web directory.

It's also kinda weird, that when we decide to compile theme from the core, like "Blank", it will also fail if one of the other themes doesn't have all "required" files.

Workaround - add some static asset i.e. web/placeholder.js

Preconditions

Magento 2.1.10

Steps to reproduce

1. Create a theme without anything in web folder
2. Run bin/magento setup:static-content:deploy

Expected result

Successful assets compilation

Actual result

  [Exception]
  Notice: Undefined offset: 5 in [...]/vendor/magento/module-deploy/Model/Deploy/LocaleDeploy.php on line 287

[magento-engcom-team]

@Igloczek, thank you for your report.
We've created internal ticket(s) MAGETWO-83997 to track progress on the issue.

[digvijay2017]

I have noticed this issue in ver 2.1.12. But, This issue has been fixed in ver 2.2.1.

[krzksz]

It seems that the issue was fixed in mentioned PRs, I have also confirmed that on Magento 2.3.x theme with empty web directory compiles properly.