[vangberg]

Closes #44

Ready for review. This ended up being more code than I anticipated, and I think I could keep changing things here and there, so I think it is better to move on and start reviewing. Don't hold back, I am very open to changing overall direction if we can make it simpler :)

Overview:

1. Versioned concern tracks model changes as Version records.
2. versioned_together groups attributes, so if one attribute changes, we record the current state of the whole group. Useful for e.g. etymology.
3. Special handling added for rich texts.
4. PublicHistory takes a Name record and fetches all relevant Version records for itself + associations and turns it into a format that is easy for the views to consume.
5. New Current model is an ActiveSupport::CurrentAttributes, which allows us to set per-request globals, i.e. current user.
6. I ditched the Unlinkable approach for the SoftDeletable concern with a default_scope. The #linked scope ended up creeping up in so many places that I think the soft-deletion approach is saner.

Tracking versions

This PR adds a Versioned concern. When included in a model, Version records are automatically created on create/update/delete, and a versions association is added to the model.

This is what an update to Name which changes proposed_in_id looks like:

>> p name.versions.last
#<Version:0x000000015401f158
 id: 20,
 record_type: "Name",
 record_id: 55876,
 operation: "update",
 changeset: {"proposed_in_id"=>[4482, 2667]},
 created_at: Fri, 02 Oct 2026 12:29:52.288092000 UTC +00:00>
irb(main):018> 

Tracking changes to etymology

A change to one etymology attribute should snapshot the current value of all etymology attributes ( + name which is used by full_etymology). This is done with versioned_together, which lets you specify which attributes should be tracked as a single attribute.

Public history

When rendering the history, we need to:

1. Only show history for some attributes -- other attributes are internal.
2. Group etymology changes together.
3. Fetch the history for associations (placements, publications, rich texts).

This is all orchestrated by Name::PublicHistory.

UI

Value flow

Single attribute

Name#syllabication

nil → 'co.li'

↓ Version#changeset

{
  'syllabication' => [nil, 'co.li']
}

↓ PublicHistory#changes_for(version)

{
  'syllabication' => [nil, 'co.li']
}

Grouped etymology

Name#etymology_xx_description

'of the colon' → 'from the colon'

↓ Version#changeset — includes unchanged companions

{
  'name' => ['E. coli', 'E. coli'],
  'etymology_xx_lang' => ['N.L.', 'N.L.'],
  'etymology_xx_description' => ['of the colon', 'from the colon']
}

↓ PublicHistory#changes_for(version) — groups before/after snapshots

{
  'etymology' => [
    {
      'name' => 'E. coli',
      'etymology_xx_lang' => 'N.L.',
      'etymology_xx_description' => 'of the colon'
    },
    {
      'name' => 'E. coli',
      'etymology_xx_lang' => 'N.L.',
      'etymology_xx_description' => 'from the colon'
    }
  ]
}

[vangberg]

My biggest issue is SoftDeletable. Unlinkable was not any better. It only exists so we can fetch versions for e.g. PublicationName that has been deleted. One (opinionated) option would be to have all versions specify an 'owner'. In this case, all versions would have a Name as an owner and we could just do Version.where(owner: name).

Quick sketch of what that would look like: https://github.com/seq-code/registry/compare/name-history...name-history-version-owner?expand=1

Hmm.