When defining abilities, scopes cover more cases because they can be
used to check permissions for a record and to filter a collection. Ruby
blocks can only be used to check permissions for a record.
Note the `Budget::Phase.kind_or_later` name sounds funny, probably
because we use the word "phase" for both an an attribute in the budgets
table and an object associated with the budget, and so naming methods
for a budget phase is a bit tricky.
Not doing so has a few gotchas when working with relations, particularly
with records which are not stored in the database.
I'm excluding the related content file because it's got a very peculiar
relationship with itself: the `has_one :opposite_related_content` has no
inverse; the relation itself is its inverse. It's a false positive since
the inverse condition is true:
```
content.opposite_related_content.opposite_related_content.object_id ==
content.object_id
```
This table will store which reports (stats, results, ...) will be shown
for a certain process (polls, budgets, ...).
Note Rails fails to save a poll and its report when both are new records
if we add a `validate :process, presence: true` rule. Since it caused a
lot of trouble when creating records for tests during factories rule
completely. Instead, I've created the `results_enabled=` and
`stats_enabled=` methods, so tests are easier to set up, while also
automatically creating a report if it doesn't already exist. This also
decouples form structure and database implemenation.
Originally I named this table `enabled_reports` and instead of having
`stats` and `results` columns, it had an `enabled` column and a `kind`
column, which would be set to "stats" or "results". However, although
that table would allow us to add arbitrary reports easily, I found the
way we had to handle the `has_many` relationship was a bit too complex.
