RSpec mocking, `name` not available from within an example group - ruby

Question

I have the following Ruby code:
def report_deviation(departure)
deviation = departure.fetch('Dev')
trip = departure.fetch('Trip')
run_id = trip.fetch('RunId')
headsign = trip.fetch('InternetServiceDesc')
timestamp = Time.now.strftime '%l:%M %P'
FileUtils.mkdir 'log' unless File.directory? 'log'
File.open DAILY_LOG_FILE, 'a' do |file|
file.puts "#{timestamp}, #{name}: Run #{run_id} (#{headsign}), deviation #{deviation}"
end
end
Tested by the following RSpec code:
describe 'report_deviation' do
let(:departure) { double }
let(:trip) { double }
let(:file) { double }
it 'appends to a log file with the correct entry format' do
expect(departure).to receive(:fetch).with('Trip').and_return trip
expect(departure).to receive(:fetch).with('Dev').and_return 'DEVIATION'
expect(trip).to receive(:fetch).with('RunId')
.and_return 'RUN'
expect(trip).to receive(:fetch).with('InternetServiceDesc')
.and_return 'HEADSIGN'
stub_const 'DeviationValidator::DAILY_LOG_FILE', :log_file
expect(File).to receive(:open).with(:log_file, 'a').and_yield file
timestamp = '12:00 pm: Run RUN (HEADSIGN), deviation DEVIATION'
expect(file).to receive(:puts).with timestamp
Timecop.freeze(Time.new 2017, 7, 31, 12) { report_deviation(departure) }
end
end
But when I run I receive the failure message:
`name` is not available from within an example (e.g. an `it` block) or from constructs that run in the scope of an example (e.g. `before`, `let`, etc). It is only available on an example group (e.g. a `describe` or `context` block).
The word name isn't written anywhere in here, and if I remove the final line of the test (which invokes the actual code) I get the test failures I would expect for unsatisfied exceptions. I normally would boil my code down to the pieces that are causing the error, but I have no idea what's causing the error.
For what it's worth, the specific line number mentioned in the backtrace is the file.puts within the File.open block - but I don't understand why that should cause a failure. I've set up test doubles such that those objects are nothing special - File receives open and yields file, whose only job is to listen for receiving puts with the string I expect. So what piece of code is calling what happens to be a keyword RSpec method name?

Answer 1

The problem is from rspec gem, if you are using Rails 6 you need to use gem 'rspec-rails', '~> 4.1.0'

Answer 2

name is not a keyword RSpec method, it's a method that report_deviation is trying to call
file.puts "#{timestamp}, #{name}: Run #{run_id} (#{headsign}), deviation #{deviation}"
but the method is not defined.
You need to define the name method in the class where report_deviation is defined. Or, if report_deviation is defined and used in the spec file, add a simple variable called name:
describe 'report_deviation' do
let(:departure) { double }
let(:trip) { double }
let(:file) { double }
let(:name) { "simple name" }
...

Answer 3

`name` is not available from within an example (e.g. an `it` block) [...]
I had a similar problem today. The final solution for the issue for now with a monkeypatch to go back to using method_name.
Create config/initializers/monkeypatches.rb file and fill inside with the following lines.
# config/initializers/monkeypatches.rb
#
# This fixes what seems to be a bug introduced by
# https://github.com/rails/rails/pull/37770
# "Modify ActiveRecord::TestFixtures to not rely on AS::TestCase:"
#
module ActiveRecord::TestFixtures
def run_in_transaction?
use_transactional_tests &&
!self.class.uses_transaction?(method_name) # this monkeypatch changes `name` to `method_name`
end
end
Credits: https://github.com/graphql-devise/graphql_devise/issues/42