In https://gitlab.com/gitlab-org/release/framework/issues/28 we found
that this method was changed a lot over the years: 43 times if our
calculations were correct. Looking at the method, it had quite a few
branches going on:
def create_or_update_import_data(data: nil, credentials: nil)
return if data.nil? && credentials.nil?
project_import_data = import_data || build_import_data
if data
project_import_data.data ||= {}
project_import_data.data = project_import_data.data.merge(data)
end
if credentials
project_import_data.credentials ||= {}
project_import_data.credentials =
project_import_data.credentials.merge(credentials)
end
project_import_data
end
If we turn the || and ||= operators into regular if statements, we can
see a bit more clearly that this method has quite a lot of branches in
it:
def create_or_update_import_data(data: nil, credentials: nil)
if data.nil? && credentials.nil?
return
else
project_import_data =
if import_data
import_data
else
build_import_data
end
if data
if project_import_data.data
# nothing
else
project_import_data.data = {}
end
project_import_data.data =
project_import_data.data.merge(data)
end
if credentials
if project_import_data.credentials
# nothing
else
project_import_data.credentials = {}
end
project_import_data.credentials =
project_import_data.credentials.merge(credentials)
end
project_import_data
end
end
The number of if statements and branches here makes it easy to make
mistakes. To resolve this, we refactor this code in such a way that we
can get rid of all but the first `if data.nil? && credentials.nil?`
statement. We can do this by simply sending `to_h` to `nil` in the right
places, which removes the need for statements such as `if data`.
Since this data gets written to a database, in ProjectImportData we do
make sure to not write empty Hash values. This requires an `unless`
(which is really a `if !`), but the resulting code is still very easy to
read.
