Bug #17093
closed
attr_accessor works strange
Description
require 'rubygems' class A def initialize(type:) @type = type end def b p type p type.nil? type = 'default' if type.nil? type end private attr_accessor :type end RSpec.describe A do let(:type) { 'whoaaa' } it 'return default' do expect(A.new(type: type).b).to eq('default') end it 'instance variable is "whoaaa"' do expect(A.new(type: type).instance_variable_get(:@type)).to eq(type) end end all tests green
output A "whoaaa" false return default instance variable is "whoaaa" 
Updated by jeremyevans0 (Jeremy Evans) over 5 years ago
- Status changed from Open to Feedback
Do you expect the type = 'default' in b to set the @type instance variable to 'default'? If so, that doesn't work, you need to use self.type = instead of type =. If not, can you provide an explanation of what behavior you are expecting?
Updated by mpavel (pavel m) over 5 years ago
seriously?
attr_accesor doesnot provide value?
Updated by jeremyevans0 (Jeremy Evans) over 5 years ago
- Status changed from Feedback to Closed
In Ruby type = 'default' only sets a local variable named type. It does not call the type= method on self, you need self.type = 'default' for that.
See https://ruby-doc.com/docs/ProgrammingRuby/html/tut_expressions.html, specifically the section on "Sidebar: Using Accessors Within a Class".
Updated by mpavel (pavel m) over 5 years ago
you doesnt see "if type.nil?" its local variable?
p type.nil? return false
next "if type.nil?" return true and "type = 'default'" will work
why?
Updated by Hanmac (Hans Mackowiak) over 5 years ago
This:
if type.nil? type = 'default' end is different from this:
type = 'default' if type.nil? because of the lexical reading, it reads the setting of local variable first and now assumes that type is local variable in this case
Updated by nobu (Nobuyoshi Nakada) over 5 years ago
- Description updated (diff)
- Status changed from Closed to Rejected
Updated by nobu (Nobuyoshi Nakada) over 5 years ago
- Has duplicate Bug #17096: attr_accessor doesnt work added
Updated by mpavel (pavel m) over 5 years ago
are you try this solution?
if type.nil? type = 'default' end just test it )