mix ash.codegen --check, fails

[Straffern]

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Versions

ash_postgres: 2.11.0
ash: 3.31.3
Elixir: 1.20.1
Erlang/OTP: 28.5.0.2

Operating system

NixOS, Linux x86_64

Current Behavior

mix ash.codegen --check raises an internal error when a Resource has multiple removed attributes and multiple added attributes.

In this case, _dev migrations also remain. The command should report the existing _dev migration error. It instead crashes before it reaches that check:

** (RuntimeError) Could not get matching name after 3 attempts.

Relevant call stack:

Mix.Tasks.Ash.Codegen.run/1
  AshPostgres.DataLayer.codegen/1
    Mix.Tasks.AshPostgres.GenerateMigrations.run/1
      AshPostgres.MigrationGenerator.generate/2
        create_migrations/5
          fetch_operations/2
            do_fetch_operations/5
              attribute_operations/4
                resolve_renames/4
                  renaming?/3
                    yes?/2
                  get_new_attribute/3
                    prompt/2

In --check mode, yes?/2 returns true, while prompt/2 returns "response".

The generator therefore confirms that a removed attribute is a rename, but then cannot find an added attribute named "response". It retries three times and raises.

The _dev migration check occurs after operation and rename inference, so the command never reaches this intended message:

Codegen check failed.

You have migrations remaining that were generated with the --dev flag.

Run `mix ash.codegen <name>` to remove the dev migrations and replace them
with production-ready migrations.

### Reproduction


1. Create a Resource with these persisted attributes:

```text
old_a
old_b
old_c
old_d

2. Generate a production-ready migration and snapshot:

mix ash.codegen initial_attributes
mix ash.migrate

3. Replace those attributes with:

new_a
new_b

4. Generate development codegen:

mix ash.codegen --dev
mix ash.migrate

5. Run the automated check:

mix ash.codegen --check

The command deterministically raises:

Could not get matching name after 3 attempts.

The relevant state is:

attributes_to_remove = [old_a, old_b, old_c, old_d]
attributes_to_add    = [new_a, new_b]
check                = true
dev                  = false

Expected Behavior

• When _dev migrations remain, it should report the existing _dev migration message.
• For ambiguous changes without _dev migrations, it should report pending codegen without inventing a rename.

[Straffern]

Happy to submit pr, if we can agree on fix being:

1. Detect remaining _dev migrations before rename inference.
2. Do not confirm interactive rename questions in --check mode.

[zachdaniel]

Yes, I agree :)