Chapter 7 Iteration B2: Unit Test of Models has a structure problem: before “One Final Change”, the book says we “rerun the tests, and they report all is well”. That cannot happen until we actually do the changes in "One Final Change”, since the tests won’t pass without the files being in “test/fixture/files”.

This should not be “One Final Change”, but mentioned before the first appearance of the string “test/fixture/files”, since user will just be confused.

I also noted that the files under “test/fixtures/active_storage” are not in the source code, are not generated, but the book implies we are modifying these already created files. It should mention that we need to create those (attachments.yml and blobs.yml).