has_one, dependent: destroy not working - ruby-on-rails

Question

I am using Devise for my user authentication and would like to destroy an associated profile along with the user.
My failing spec looks like this:
it "should destroy associated profile" do
profile = #user.profile
#user.destroy
expect(profile).to be_nil
end
And
In my user model:
has_one :profile, dependent: :destroy
In my profile model:
belongs_to :user
In the console, I can reproduce the issue like this:
2.0.0p247 :001 > #user = FactoryGirl.create(:user)
(1.5ms) BEGIN
User Exists (2.9ms) SELECT 1 AS one FROM "users" WHERE "users"."email" = 'person946979#example.com' LIMIT 1
User Exists (1.7ms) SELECT 1 AS one FROM "users" WHERE LOWER("users"."email") = LOWER('person946979#example.com') LIMIT 1
SQL (15.7ms) INSERT INTO "users" ("created_at", "email", "encrypted_password", "name", "updated_at") VALUES ($1, $2, $3, $4, $5) RETURNING "id" [["created_at", Fri, 16 Aug 2013 01:21:12 UTC +00:00], ["email", "person946979#example.com"], ["encrypted_password", "$2a$10$0704XOlw.6ZE4HEfDhaIeuwnEbbJZvZda3Jwr052aLS5z3G77Dgja"], ["name", "Example User"], ["updated_at", Fri, 16 Aug 2013 01:21:12 UTC +00:00]]
SQL (3.8ms) INSERT INTO "profiles" ("created_at", "updated_at", "user_id") VALUES ($1, $2, $3) RETURNING "id" [["created_at", Fri, 16 Aug 2013 01:21:12 UTC +00:00], ["updated_at", Fri, 16 Aug 2013 01:21:12 UTC +00:00], ["user_id", 25]]
Profile Load (3.4ms) SELECT "profiles".* FROM "profiles" WHERE "profiles"."user_id" = $1 ORDER BY "profiles"."id" ASC LIMIT 1 [["user_id", 25]]
(2.2ms) COMMIT
=> #<User id: 25, email: "person946979#example.com", encrypted_password: "$2a$10$0704XOlw.6ZE4HEfDhaIeuwnEbbJZvZda3Jwr052aLS5...", reset_password_token: nil, reset_password_sent_at: nil, remember_created_at: nil, sign_in_count: 0, current_sign_in_at: nil, last_sign_in_at: nil, current_sign_in_ip: nil, last_sign_in_ip: nil, created_at: "2013-08-16 01:21:12", updated_at: "2013-08-16 01:21:12", name: "Example User">
2.0.0p247 :002 > #user.destroy
(1.0ms) BEGIN
SQL (2.5ms) DELETE FROM "profiles" WHERE "profiles"."id" = $1 [["id", 4]]
SQL (5.4ms) DELETE FROM "users" WHERE "users"."id" = $1 [["id", 25]]
(2.0ms) COMMIT
=> #<User id: 25, email: "person946979#example.com", encrypted_password: "$2a$10$0704XOlw.6ZE4HEfDhaIeuwnEbbJZvZda3Jwr052aLS5...", reset_password_token: nil, reset_password_sent_at: nil, remember_created_at: nil, sign_in_count: 0, current_sign_in_at: nil, last_sign_in_at: nil, current_sign_in_ip: nil, last_sign_in_ip: nil, created_at: "2013-08-16 01:21:12", updated_at: "2013-08-16 01:21:12", name: "Example User">
Interestingly, the user appears to actually have been deleted.
2.0.0p247 :003 > #user.reload.destroy
User Load (2.7ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 25]]
ActiveRecord::RecordNotFound: Couldn't find User with id=25
What is going on here?

Answer 1

Your model seems fine. Try something like this:
it "should destroy associated profile" do
profile = #user.profile
#user.destroy
expect(Profile.find(profile.id)).to be_nil
end
Like Heungju said, while the database row that corresponds to profile is being destroyed, the variable itself isn't.

Answer 2

How about this?
it "should destroy associated profile" do
profile = #user.profile
#user.destroy
expect(#user.profile).to be_nil
end
After #user.destroy, the 'profile', variable that expected to be nil, was not changed. I think...

Answer 3

Rewriting my spec like this does what I need:
it "should destroy associated profile" do
expect {
#user.destroy
}.to change(Profile, :count).by(-1)
end