Eliminate dependency on doctrine/common

[Majkl578]

What is used through doctrine/common dependency:

• Doctrine\Common\Util\Debug - likely to be dropped, only used in one console command and one test
• Doctrine\Common\Event* to be extracted to doctrine/event-manager (for now)
• Doctrine\Common\Persistence -> needs doctrine/persistence
• Doctrine\Common\Util\Inflector -> should be switched to doctrine/inflector
• Doctrine\Common\Lexer -> should be switched to doctrine/lexer (later removed)
• Doctrine\Common\{PropertyChangedListener,NotifyPropertyChanged} -> likely to be merged into ORM

cross references:
DBAL: doctrine/dbal#3176
Migrations: doctrine/migrations#722

[stof]

Doctrine\Common{PropertyChangedListener,NotifyPropertyChanged} -> likely to be merged into ORM

should they go in the ORM, or in doctrine/persistence to be reusable for the ODM projects ?

[Jean85]

Will this be feasible in the 2.x branch? Or are we forced to wait for 3.x due to BC?

[Ocramius]

Due to BC reasons, dropping the dependency on Doctrine\Common will be problematic here, so it will be done in such a way that the components are no longer used, but still added as dependency.

[Jean85]

So requiring the split packages and using Composer's provide will be a feasible upgrade path? Great!

[Majkl578]

I don't think it's possible in 2.x, especially because of the Doctrine\Common\Proxy dependency.

[Jean85]

Umh... Maybe we can write down a shim/polyfill that uses ProxyManager under the hood, but provides aliases for Doctrine\Common\Proxy? Or the behavior is too different?

[Ocramius]

That's a lot of work that really isn't worth it. I already tried working towards a BC-friendly way of doing it, and it is feasible, but its at least a couple of full days of work.

[Majkl578]

Handled in #7497.