Introducing parent/child themes

[ahilles107]

What do you think about idea of declaring parent theme for theme and parameter parent_theme in path_patterns ? This would allow for us implement themes updating and keeping customer/user theme changes not removed.

Something like:

themes: 
  theme_1: ~
  theme_2: ~
  theme_3: 
    parent: theme_1

[ahilles107]

@lsmith77 - what do You think?

[lsmith77]

should't twig inheritance be sufficient?

[wizhippo]

I think using theme cascading order could be used here. It would be nice if there was a way to change the patterns based on the current theme selected so you could add base themes to the cascade order based on the active theme..

Perhaps the FileLocator could be changed to allow changing the patterns and then some listener to update the cascade order based on the current theme?

[oleg-andreyev]

@wizhippo I my company we've have quite complicated template inheritance, and we've achieved that using path_patterns will all paths.