Theming broken after trying to enabling a second theme

[patrickjahns]

After trying to activity another theme - ownCloud behaves strange

IMPORTANT NOTE this only broken when templateeditor is enabled

Steps to reproduce

Pre-Conidtion:

Have templateeditor 0.3 installed + enabled

First scenario - broken general section

1. Take ownCloud 10.0.8RC1 with enterprise theme
2. Go to Apps -> try to enable theme-example -> (Error Message theme-example can't be enabled until theme-enterprise is disabled. should be shown )
3. Go browse to general section and see it blank:
   

second scenario - "split theme brain"

1. Take ownCloud 10.0.8RC1 with enterprise theme
2. Go to Apps -> try to enable theme-example -> (Error Message theme-example can't be enabled until theme-enterprise is disabled. should be shown )
3. Disable theme-enterprise
4. browse to general section and see theme-example being used
   

Expected behaviour

General section works as before trying to enable the theme.

Actual behaviour

broken general section

split theme

Logs

ownCloud log (data/owncloud.log)

{"reqId":"42azotaIYRMVldUbjbTm","level":3,"time":"2018-04-16T09:10:30+00:00","remoteAddr":"172.18.0.1","user":"admin","app":"core","method":"POST","url":"\/index.php\/settings\/ajax\/enableapp.php","message":"theme-example can't be enabled until theme-enterprise is disabled."}
{"reqId":"NsCi0SJGdiOh1fccNUTJ","level":3,"time":"2018-04-16T09:10:38+00:00","remoteAddr":"172.18.0.1","user":"admin","app":"PHP","method":"GET","url":"\/settings\/admin?sectionid=general","message":"Cannot declare class OC_Theme, because the name is already in use at \/var\/www\/owncloud\/apps\/theme-example\/defaults.php#21"}
{"reqId":"TYevcho3daWp4Axqdu9C","level":3,"time":"2018-04-16T09:10:42+00:00","remoteAddr":"172.18.0.1","user":"admin","app":"PHP","method":"GET","url":"\/settings\/admin?sectionid=general","message":"Cannot declare class OC_Theme, because the name is already in use at \/var\/www\/owncloud\/apps\/theme-example\/defaults.php#21"}
{"reqId":"QqRiDA4QclY51j3tJReh","level":3,"time":"2018-04-16T09:11:13+00:00","remoteAddr":"172.18.0.1","user":"admin","app":"PHP","method":"GET","url":"\/settings\/admin?sectionid=general","message":"Cannot declare class OC_Theme, because the name is already in use at \/var\/www\/owncloud\/apps\/theme-example\/defaults.php#21"}
{"reqId":"tVkTCLg9u4BRGGd7msPx","level":3,"time":"2018-04-16T09:14:20+00:00","remoteAddr":"172.18.0.1","user":"admin","app":"PHP","method":"GET","url":"\/settings\/admin?sectionid=general","message":"Cannot declare class OC_Theme, because the name is already in use at \/var\/www\/owncloud\/apps\/theme-example\/defaults.php#21"}

[pmaier1]

This should be fixed for 10.0.8 final if possible.

[ownclouders]

GitMate.io thinks possibly related issues are #13402 (... broken), #3209 (Theming), #30887 ([theme-example] Enable only for specific groups ???), #30948 ([Stable10] Protect themes against enabling for groups), and #3645 (Theme Backup).

[tomneedham]

@VicDeo ?

[VicDeo]

@patrickjahns is any kind of cache enabled?

[VicDeo]

please disregard as it's not related to caching.
wow... it's a win-win combination :)
template editor iterates through the themes provided by the core OC\ThemeThemeService
https://github.com/owncloud/core/blob/master/lib/private/Theme/ThemeService.php#L136 actually loads and applies a theme
so if there is no active theme (theme-enterprise is disabled) the latest available theme will be applied to the templateeditor page.

and another issue that we just can't load two app-themes at the same time due to the file defaults.php that contains the class OC_Theme...

[VicDeo]

#31151

[PVince81]

Is there a workaround like letting the admin disable second theme on the CLI ?

[PVince81]

@pmaier1 @felixboehm let's move this to 10.0.9, there's a workaround and the PR isn't ready for merge