Unit Testing getting me confused, not able to make test respond like application, where application is correct.

rubyonrails-talk
1

I have a few test cases, using unit test, I am new to testing but I don’t understand why, if fixtures are loaded and validations are in place (in my case, I am testing that identical objects should not be saved to the database) – and I know that it works, because doing the test through the UI gives the right behavious, but the test does not behave as the actual application does, and should…

TEST REPORT:

  1. Failure:

test_should_have_loaded_this_fixture_item_into_the_test_database_already(CollectionTest) [test/unit/collection_test.rb:16]:

Should not be valid

  1. Failure:

test_should_not_save_with_duplicate_name_property(CollectionTest) [test/unit/collection_test.rb:11]:

Saved a collection with a duplicate name

TEST CODE:

test “should not save with duplicate name property” do

c = collections(:one)

assert !c.save, ‘Saved a collection with a duplicate name’

end

test “should have loaded this fixture item into the test database already” do

c = collections(:one)

assert !c.valid?, ‘Should not be valid’

assert c.save, ‘Did not save first item’

c2 = collections(:one)

assert_equal c, c2, “Two items are not equal”

assert !c2.save, ‘Saved duplicate item as well’

end

2

I have a few test cases, using unit test, I am new to testing but I don't understand why, if fixtures are loaded and validations are in place (in my case, I am testing that identical objects should not be saved to the database) -- and I know that it works, because doing the test through the UI gives the right behavious, but the test does not behave as the actual application does, and should...

collections(:one) will get you an object that is already in the database, calling save on it will just update it, not insert a duplicate. Assuming that there is no other fixture with the same name as collections(:one), there is no reason why it shouldn't be valid.

Fred

3

Interesting, I thought I had to do a collections(:one).find for it to be taken out of the database, according to the documentation… but i did notice, and my next question was going to be, why do I get an error when doing the find method in the test?

  1. So, I guess it is not true that in order to get the values from the fixture you do this: “collections(:one)” ?
  2. And in order to get the values from the db you do this instead: “collections(:one).find” ?
4

For example this is the documentation at:

http://guides.rubyonrails.org/testing.html#the-low-down-on-fixtures

# this will return the Hash for the fixture named david

users(``:david``)

# using the find method, we grab the "real" david as a User

david = users(``:david``).find

``

5

OK i think I fixed it by doing this instead:

test “should not save with duplicate name property” do

c = Collection.new(collections(:one))

assert !c.save, ‘Saved a collection with a duplicate name’

end