Add Find Or Create A Record With FactoryBot as a Rails til

rails/find-or-create-a-record-with-factory-bot.md

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+# Find Or Create A Record With FactoryBot
+
+I have a bunch of tests throughout my test suite that rely on a particular kind
+of unique record. Let's say it is a special admin user.
+
+```ruby
+admin = FactoryBot.create(:user, email: 'admin@company.com')
+```
+
+If this user has already been created then trying to re-create it with
+[FactoryBot](https://github.com/thoughtbot/factory_bot) will result in a unique
+email validation error.
+
+Another way to approach this would be to either find or create the admin user.
+In some standard Rails code that might look like this:
+
+```ruby
+admin =
+  User.find_by(email: 'admin@company.com') ||
+  FactoryBot.create(:user, email: 'admin@company.com')
+```
+
+There is some repetitiveness to this that I'd like to avoid. FactoryBot doesn't
+have an equivalent to ActiveRecord's `find_and_create_by`, but we can work
+around this.
+
+We can add an `initialize_with` directive to the `User` factory.
+
+```ruby
+FactoryBot.define do
+  factory :user do
+    sequence(:email) { |n| 'user#{n}@example.com' }
+
+    # a bunch of other attributes
+
+    initialize_with { User.find_or_create_by(email: email) }
+  end
+end
+```
+
+With this in place, we can call `FactoryBot.create` with the already existing
+_admin_ user and it will look up the record instead of raising a validation
+error.
+
+[source](https://stackoverflow.com/a/11799674/535590)