# `Statifier.Validator.Checks.Final`
[🔗](https://github.com/riddler/statifier-ex/blob/v2.6.0/lib/statifier/validator/checks/final.ex#L1)

Check 6 (spec 3.7): a `:final` state's content model is `onentry`,
`onexit`, and `donedata` - nothing else. Two reasons, each reported once
per offending child and at the **child's own** `location` rather than the
`<final>`'s, so the caret lands on the element that should not be there:

- `{:final_has_states, id}` for a state child, `id` being the child's.
- `{:final_has_transitions, id}` for a `<transition>` child, `id` being
  the `<final>`'s - a `<final>` is where a region stops, so it has no
  outgoing transition to take. This case was deferred at first, then
  folded into this module rather than growing a ninth check for one
  more child type.

An `initial` attribute or `<initial>` element on a `:final` is *not*
reported here: check 3 already refuses it as `:initial_on_atomic_state`
(`Checks.InitialTargets`'s `atomic_for_initial?/1` counts `:final`), and
reporting it twice would be two errors for one mistake.

# `check`

```elixir
@spec check(
  document :: Statifier.Document.t(),
  context :: Statifier.Validator.Context.t()
) :: [
  Statifier.Validator.Error.t()
]
```

Returns a `:final_has_states` error for every state child of a `:final`
state and a `:final_has_transitions` error for every `<transition>` child
of one - a `<final>`'s only legal content is `onentry`, `onexit`, and
`donedata`. An `initial` attribute or `<initial>` element on a `:final` is
not reported here; check 3 already owns that mistake. Returns `[]` when no
`:final` state carries an illegal child.

---

*Consult [api-reference.md](api-reference.md) for complete listing*