Select base field plugins

If we want to offer plugin configuration options for base fields / entity it would mean that we need to have a similar table to the one for configurable fields.

Possibly just offer one single field list containing both fields to enable and plugins to choose and configure.

If we want to do that then we need to rethink a bit the level of control for we want to offer for comparing a field and configuring the plugin for that field.

Currently the base fields compare/don't compare setting can be configured per entity. Configurable fields configuration (including compare/don't compare setting) is global for all entities i.e. if from configurable fields tab a field type is not compared then it will not show up for comparison on any entity.
However there is another level of control at the bundle level with view modes. If a bundle wants to compare only certain fields then it should create a view mode and hide the fields which shouldn't be compared.

1. Currently

Note: when word 'visibility' is used below it has the following meaning: the possibility to show/hide a field in a comparison.

Base fields

• visibility: can be configured per entity
• plugin configuration: not configurable ATM

Configurable fields

• visibility:
  • if no plugin selected => not compared anywhere
  • if plugin selected => visibility can be controlled by view modes
• plugin configuration: the plugin configuration is global (applied to all entities using that field type)

2. Merging base fields with configurable fields

First of all this would be a big change and would require quite some work.
For every entity we could list the base fields of that entity + all the configurable fields attached to that entity bundle.

Result:

Base fields

• visibility: can be configured per entity
• plugin configuration: configurable

Configurable fields

• visibility:
• if no plugin selected => not compared on that entity
• if plugin selected => visibility can be controlled by view modes
• plugin configuration: the plugin configuration is per entity