From: shugo@...
Date: 2015-12-17T22:05:54+00:00
Subject: [ruby-core:72224] [Ruby trunk - Bug #11827] StringIO with set_encoding broken with enabled frozen string literal

Issue #11827 has been updated by Shugo Maeda.


Yui NARUSE wrote:
> Away from the case and thinking ideal behavior, StringIO should be a view of given source string and set_encoding shouldn't change source encoding.
> But I'm not sure that it is worth breaking the compatibility.

FYI, nobu figured out that open-uri depends on the current behavior:

```ruby
      enc = Encoding::ASCII_8BIT unless enc
      if self.respond_to? :force_encoding
        self.force_encoding(enc)
      elsif self.respond_to? :string
        self.string.force_encoding(enc)
      else # Tempfile
        self.set_encoding enc
      end
    end
```


----------------------------------------
Bug #11827: StringIO with set_encoding broken with enabled frozen string literal
https://bugs.ruby-lang.org/issues/11827#change-55633

* Author: deepj #
* Status: Feedback
* Priority: Normal
* Assignee: 
* ruby -v: ruby 2.3.0preview2 (2015-12-11 trunk 53028) [x86_64-darwin15]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN
----------------------------------------
I'm not sure if this the following problem is an expected behavior. But I guess, it is a bug when I run the code below. It throws `set_encoding': can't modify frozen String (RuntimeError).

~~~
# frozen_string_literal: true

io = StringIO.new('')
io.set_encoding(Encoding::BINARY)
~~~

I wouldn't expect this kind of behavior.




-- 
https://bugs.ruby-lang.org/