mix ash.codegen fails with KeyError :source not found in: nil when referencing a non-existent field in check_constraints

[shahryarjb]

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Versions

main

Operating system

mac os last version

Current Behavior

Running mix ash.codegen crashes with a KeyError when a check_constraints references a field that doesn’t exist in the resource. The error message doesn’t clearly indicate which field caused the issue

➜  mishka_cms git:(master) ✗ mix ash.codegen mishka_file
Getting extensions in current project...
Running codegen for AshGraphql.Resource...
Running codegen for AshPostgres.DataLayer...
** (KeyError) key :source not found in: nil

If you are using the dot syntax, such as map.field, make sure the left-hand side of the dot is a map
    (ash_postgres 2.6.23) lib/migration_generator/migration_generator.ex:3163: anonymous fn/2 in AshPostgres.MigrationGenerator.check_constraints/1
    (elixir 1.18.4) lib/enum.ex:1714: Enum."-map/2-lists^map/1-1-"/2
    (ash_postgres 2.6.23) lib/migration_generator/migration_generator.ex:3158: anonymous fn/2 in AshPostgres.MigrationGenerator.check_constraints/1
    (elixir 1.18.4) lib/enum.ex:1714: Enum."-map/2-lists^map/1-1-"/2
    (ash_postgres 2.6.23) lib/migration_generator/migration_generator.ex:3110: AshPostgres.MigrationGenerator.do_snapshot/3
    (ash_postgres 2.6.23) lib/migration_generator/migration_generator.ex:3100: AshPostgres.MigrationGenerator.get_snapshots/2
    (elixir 1.18.4) lib/enum.ex:4442: Enum.flat_map_list/2
    (elixir 1.18.4) lib/enum.ex:4445: Enum.flat_map_list/2

Reproduction

No response

Expected Behavior

Show what resource has this problem at least! or migration!
Thank you in advance

Ref: https://discord.com/channels/711271361523351632/1259099945366061110/1436989926246846524