Hi
I’m struggling to find a neat way to spec this. The Sequel ORM
doesn’t support automatically destroying dependent models. It’s easy
enough to do in a callback though:
class Changeset < Sequel::Model
has_many :migrations, :class => DataModel::Migration
before_destroy do
migrations.each { |m| m.destroy }
end
# ...
end
The problem is isolating it from the database to test. I want to know
that when I send Changeset#destroy that each migration is destroyed.
The implementation of Sequel::Model#destroy (from the RDoc) is this:
File sequel/lib/sequel_model/record.rb, line 325
325: def destroy
326: db.transaction do
327: before_destroy
328: delete
329: after_destroy
330: end
331: self
332: end
Now, if a database isn’t wired up, Sequel complains if you do anything
database related, and that includes using associations. So the best I
have so far is this:
describe “#destroy” do
before(:each) do
# …
@changeset = DataModel::Changeset.new
end
it "should fire a before_destroy hook to destroy all Migrations" do
class << @changeset
def destroy
before_destroy
end
end
@changeset.stub!(:migrations).and_return(
[@migration_1, @migration_2])
@migration_1.should_receive(:destroy)
@migration_2.should_receive(:destroy)
@changeset.destroy
end
end
So I’ve committed these sins:
- redefined someone else’s code, when I depend on the real version at
runtime - included an assumption about the external code in my stub
- stubbed out a method on the object under test
In sort, it’s suckitude of the highest order. But I don’t know how to
do this without resorting to an in-memory SQLite database or something.
Any help much appreciated.
Ashley