Forum: Ruby-core [ruby-trunk - Bug #7773][Open] Calling send("attribute=", value) returns nil instead of value

Issue #7773 has been reported by gaffneyc (Chris Gaffney).

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Bug #7773: Calling send("attribute=", value) returns nil instead of 
value
https://bugs.ruby-lang.org/issues/7773

Author: gaffneyc (Chris Gaffney)
Status: Open
Priority: Normal
Assignee:
Category:
Target version:
ruby -v: 2.0.0-rc1


When calling an attribute writer created using either attr_accessor or 
attr_writer via send nil is returned from the send call instead of the 
new value.

I've attached a test case that is failing on current head (51794) and 
2.0.0-rc1. I've done a git bisect and it looks like commit 37228 
(db1e99cd) is the first offending commit.

I've been able to reproduce on OS X 10.8 and Ubuntu 12.04.

Issue #7773 has been updated by nobu (Nobuyoshi Nakada).

Status changed from Open to Feedback

Why do you consider it a bug?
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Bug #7773: Calling send("attribute=", value) returns nil instead of 
value
https://bugs.ruby-lang.org/issues/7773#change-35896

Author: gaffneyc (Chris Gaffney)
Status: Feedback
Priority: Normal
Assignee:
Category:
Target version:
ruby -v: 2.0.0-rc1


When calling an attribute writer created using either attr_accessor or 
attr_writer via send nil is returned from the send call instead of the 
new value.

I've attached a test case that is failing on current head (51794) and 
2.0.0-rc1. I've done a git bisect and it looks like commit 37228 
(db1e99cd) is the first offending commit.

I've been able to reproduce on OS X 10.8 and Ubuntu 12.04.

Issue #7773 has been updated by marcandre (Marc-Andre Lafortune).

Category set to core
Status changed from Feedback to Open
Target version set to 2.0.0

nobu (Nobuyoshi Nakada) wrote:
> Why do you consider it a bug?

I don't know about Chris, but here is why I consider it a bug:
* returning nil is less useful than value
* it is less intuitive too (to me)
* it is a change of behavior (possibly breaking some existing code)
* this change of behavior was never announced, discussed or approved 
AFAIK
* the referred commit has no stated or implied intention to change this
* the referred commit has no test to that effect

What I wonder is: why do you consider it could possibly be a feature?

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Bug #7773: Calling send("attribute=", value) returns nil instead of 
value
https://bugs.ruby-lang.org/issues/7773#change-35923

Author: gaffneyc (Chris Gaffney)
Status: Open
Priority: Normal
Assignee:
Category: core
Target version: 2.0.0
ruby -v: 2.0.0-rc1


When calling an attribute writer created using either attr_accessor or 
attr_writer via send nil is returned from the send call instead of the 
new value.

I've attached a test case that is failing on current head (51794) and 
2.0.0-rc1. I've done a git bisect and it looks like commit 37228 
(db1e99cd) is the first offending commit.

I've been able to reproduce on OS X 10.8 and Ubuntu 12.04.

Issue #7773 has been updated by gaffneyc (Chris Gaffney).


I consider it a bug because the behavior only happens using `send`. If I 
were to call `bar=` directly (see below) it returns the value that was 
set.

class Foo
  attr_writer :bar
end

Foo.new.bar = "test" # => "test"

Should `send` behave differently than sending the message directly?
----------------------------------------
Bug #7773: Calling send("attribute=", value) returns nil instead of 
value
https://bugs.ruby-lang.org/issues/7773#change-35926

Author: gaffneyc (Chris Gaffney)
Status: Open
Priority: Normal
Assignee:
Category: core
Target version: 2.0.0
ruby -v: 2.0.0-rc1


When calling an attribute writer created using either attr_accessor or 
attr_writer via send nil is returned from the send call instead of the 
new value.

I've attached a test case that is failing on current head (51794) and 
2.0.0-rc1. I've done a git bisect and it looks like commit 37228 
(db1e99cd) is the first offending commit.

I've been able to reproduce on OS X 10.8 and Ubuntu 12.04.

Issue #7773 has been updated by mame (Yusuke Endoh).

Status changed from Open to Assigned
Assignee set to nobu (Nobuyoshi Nakada)

gaffneyc (Chris Gaffney) wrote:
> I consider it a bug because the behavior only happens using `send`.

Actually, it is not a bug itself.
An assignment-like method call always returns its right value rather 
than the return value from the method.
The following code shows the difference:

  class Foo
    def foo=(x)
      "foo"
    end
  end
  x = Foo.new
  p(x.foo = 42)        #=> 42
  p(x.send(:foo=, 42)) #=> "foo"


However, as MarcAndre said, a method defined by attr_accessor used to 
return its argument, at least in ruby 1.9.3p194.
There seems to be a regression.  Nobu, could you investigate it?

--
Yusuke Endoh <mame@tsg.ne.jp>
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Bug #7773: Calling send("attribute=", value) returns nil instead of 
value
https://bugs.ruby-lang.org/issues/7773#change-35927

Author: gaffneyc (Chris Gaffney)
Status: Assigned
Priority: Normal
Assignee: nobu (Nobuyoshi Nakada)
Category: core
Target version: 2.0.0
ruby -v: 2.0.0-rc1


When calling an attribute writer created using either attr_accessor or 
attr_writer via send nil is returned from the send call instead of the 
new value.

I've attached a test case that is failing on current head (51794) and 
2.0.0-rc1. I've done a git bisect and it looks like commit 37228 
(db1e99cd) is the first offending commit.

I've been able to reproduce on OS X 10.8 and Ubuntu 12.04.

Issue #7773 has been updated by marcandre (Marc-Andre Lafortune).


I meant to assign it to myself... in any case, it's fixed with r39121.
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Bug #7773: Calling send("attribute=", value) returns nil instead of 
value
https://bugs.ruby-lang.org/issues/7773#change-35937

Author: gaffneyc (Chris Gaffney)
Status: Closed
Priority: Normal
Assignee: nobu (Nobuyoshi Nakada)
Category: core
Target version: 2.0.0
ruby -v: 2.0.0-rc1


When calling an attribute writer created using either attr_accessor or 
attr_writer via send nil is returned from the send call instead of the 
new value.

I've attached a test case that is failing on current head (51794) and 
2.0.0-rc1. I've done a git bisect and it looks like commit 37228 
(db1e99cd) is the first offending commit.

I've been able to reproduce on OS X 10.8 and Ubuntu 12.04.