Strange behavior in rspec when raising exception - ruby

Question

I am trying to figure out why the following spec won't pass when the expect and actual results look the same
1) Moodle::Client raises moodle error if token is invalid
Failure/Error: expect {
expected Moodle::MoodleError with {"exception"=>"moodle_exception", "errorcode"=>"invalidtoken", "message"=>"Invalid token - token not found"}, got #<Moodle::MoodleError: {"exception"=>"moodle_exception", "errorcode"=>"invalidtoken", "message"=>"Invalid token - token not found"}> with backtrace:
# ./lib/moodle/client.rb:27:in `resolve_request'
# ./lib/moodle/client.rb:11:in `method_missing'
# ./spec/moodle/client_spec.rb:48:in `block (4 levels) in <module:Moodle>'
# ./spec/moodle/client_spec.rb:47:in `block (3 levels) in <module:Moodle>'
# /Users/ryanme/.rvm/gems/ruby-2.2.2#phoenix/gems/vcr-2.9.3/lib/vcr/util/variable_args_block_caller.rb:9:in `call'
# /Users/ryanme/.rvm/gems/ruby-2.2.2#phoenix/gems/vcr-2.9.3/lib/vcr/util/variable_args_block_caller.rb:9:in `call_block'
# /Users/ryanme/.rvm/gems/ruby-2.2.2#phoenix/gems/vcr-2.9.3/lib/vcr.rb:182:in `use_cassette'
# ./spec/moodle/client_spec.rb:46:in `block (2 levels) in <module:Moodle>'
# ./spec/moodle/client_spec.rb:47:in `block (3 levels) in <module:Moodle>'
# /Users/ryanme/.rvm/gems/ruby-2.2.2#phoenix/gems/vcr-2.9.3/lib/vcr/util/variable_args_block_caller.rb:9:in `call'
# /Users/ryanme/.rvm/gems/ruby-2.2.2#phoenix/gems/vcr-2.9.3/lib/vcr/util/variable_args_block_caller.rb:9:in `call_block'
# /Users/ryanme/.rvm/gems/ruby-2.2.2#phoenix/gems/vcr-2.9.3/lib/vcr.rb:182:in `use_cassette'
# ./spec/moodle/client_spec.rb:46:in `block (2 levels) in <module:Moodle>'
The code is still work in progress:
require 'typhoeus'
module Moodle
class Client
attr_reader :web_service_name, :filter_params
def method_missing message, *args, &block
if supports_web_service? message
#web_service_name = message
#filter_params = args.first
resolve_request
else
super
end
end
def supports_web_service? name
true # change to look at configuration for web services
end
def resolve_request
response = request.run
json_body = JSON.parse(response.body)
if json_body['exception']
raise MoodleError, json_body
else
json_body
end
end
def request
Typhoeus::Request.new(Moodle.configuration.api_url,
method: :post,
params: request_params,
headers: { 'Accept' => "json" })
end
def request_params
filter_params.merge!({ moodlewsrestformat: Moodle.configuration.format,
wsfunction: web_service_name,
wstoken: Moodle.configuration.token })
end
end
end
The spec spec is below:
it 'raises moodle error if token is invalid' do
Moodle.configure do|c|
c.host = 'http://dev.vle.getsmarter.co.za'
c.token = 'invalidtoken'
end
expected_response = {"exception"=>"moodle_exception","errorcode"=>"invalidtoken","message"=>"Invalid token - token not found"}
VCR.use_cassette("valid_service_with_invalid_token") do
expect {
Moodle::Client.new.core_user_get_users(params)
}.to raise_error(Moodle::MoodleError, expected_response)
end
end
My question is why is it breaking? Does it have something to do with the backtrace? Also any ideas on how to fix it would be great.

Answer 1

raise_error doesn't take a hash but an error message (either string or regexp).
This would work:
expect {
Moodle::Client.new.core_user_get_users(params)
}.to raise_error(Moodle::MoodleError, 'Invalid token - token not found')
You can set additional expectations by passing a block, e.g.:
expect {
Moodle::Client.new.core_user_get_users(params)
}.to raise_error(Moodle::MoodleError, 'Invalid token - token not found') { |error|
expect(error.errorcode).to eq('invalidtoken')
}