How to exclude file from external library

Hi there,

>When i try mark file as plain text in external library it was no any effect.

Unfortunately it does not work for External Libraries yet -- https://youtrack.jetbrains.com/issue/WI-22649 --watch it (star/vote/comment) to get notified on any progress.

>I can't modify original file in external library because it's update with composer.

>But when I create a copy of file in the Sources folder, I receive an error "class multiple implementation"

As fas as I see it -- that's the only way for now. It's better to have "multiple implementation" weak warning than more serious warning from IDE side (of course it only applies if everything else with this approach works fine).

Have a look at these tickets as well:

• https://youtrack.jetbrains.com/issue/WI-22564
• https://youtrack.jetbrains.com/issue/WI-6748

P.S. How often do you update that library? If rarely -- consider actually editing your local copy.

Other (not so great) ideas:

• submit PR to the library authors (they may accept it if you provide good reasoning)
• create and use your own fork of that library where you can edit the code as you wish