Testing PG Constraint in Rails

Using Rails 6.0.3.4, Minitest, PG, Ruby 2.7.2

I created a migration in my Rails project which introduces a CONSTRAINT on my Service model.

      ALTER TABLE services
        ADD CONSTRAINT version CHECK (
          CASE WHEN version = 1 AND id != original_service_id then FALSE
          WHEN version != 1 AND id = original_service_id then FALSE
          WHEN version != 1 AND deprecated_since IS NULL then FALSE
          WHEN version =1 AND deprecated_since IS NOT NULL then FALSE
          END
          );

After executing rails db:migrate successfully, I use rails console to test the CONSTRAINT "manually", I get the expected behaviour. An exception is raised.

Console input:

    Forge::Service.insert(specialty_id: 1, name: "a", description: "a",
      created_at: Time.now, updated_at: Time.now, version: 2)

Console output:

ActiveRecord::StatementInvalid: PG::CheckViolation: ERROR:  new row for relation "services" violates check constraint "version" DETAIL:  Failing row contains (71, a, a, f, 2, null, 1, null, 2021-02-13 18:46:43.635609, 2021-02-13 18:46:43.635614).

I then created a test to confirm the behaviour but I am not able to reproduce the same result.

  test "cannot insert to db with invalid version" do
      assert_raise(Exception) do

        Forge::Service.insert(specialty_id: 1, name: "a", description: "a",
          created_at: Time.now, updated_at: Time.now, version: 2)

      end
    end

The test produces the following result.

    Failure:
    Forge::ServiceTest#test_cannot_insert_to_db_with_invalid_version [/home/francis/code/s21385/bumble-z/test/models/forge/service_test.rb:129]:
    Exception expected but nothing was raised.
    
    
    rails test test/models/forge/service_test.rb:128

I used Service.count before and after my test and a new record is effectively created so clearly my PG CONSTRAINT is not applied while testing.

I tried dropping the RAILS_ENV=test db and loading it but I am getting the same issue.