Bug #7752: Rational/Float/Fixnum/Bignum `.to_s.encoding` is US-ASCII

• Status: Rejected
• Assignee: -
• Target version: 2.0.0
• ruby -v: 2.0.0dev

[coffeejunk (Maximilian Haack)]

=begin
When converting an instance of Rational/Float/Fixnum/Bignum to a string with the (({.to_s})) method, the resulting string has the encoding US-ASCII. This happens for 1.9.3 as well as 2.0.0rc1.

(({> ENCODING}))
(({ => #Encoding:UTF-8}))

(({> Encoding.default_internal}))
(({ => #Encoding:UTF-8}))

(({> Encoding.default_external}))
(({ => #Encoding:UTF-8}))

(({> 1.to_s.encoding}))
(({#=> #Encoding:US-ASCII}))

(({> (2/1).to_r.to_s.encoding}))
(({ => #Encoding:US-ASCII}))

(({> "abc".encoding}))
(({ => #Encoding:UTF-8}))

=end

[drbrain (Eric Hodel)]

• Category set to core

This behavior matches Time#to_s, see #5226

Since there are no non-US-ASCII characters in the result of to_s on Rational, Float, Fixnum or Bignum there should be no problem with the US-ASCII encoding. Can you demonstrate one?

[coffeejunk (Maximilian Haack)]

The only problem I see is that ruby is lying to the user. It is not severe since, as you said, there are no non-ascii characters in the resulting string, but I think ruby should respect the set encoding.

[jballanc (Joshua Ballanco)]

US-ASCII is a strict subset of UTF-8, so I don't think there's necessarily any lying involved.

[naruse (Yui NARUSE)]

• Status changed from Open to Rejected

On current policy, strings which always include only US-ASCII characters are US-ASCII.
If there is a practical issue, I may change the policy in the future.

Note that US-ASCII string is faster than UTF-8 on getting length or index access.

[duerst (Martin Dürst)]

On 2013/01/31 18:07, coffeejunk (Maximilian Haack) wrote:

Issue #7752 has been updated by coffeejunk (Maximilian Haack).

The only problem I see is that ruby is lying to the user.

There is 0% lying if one claims that an ASCII-only string is US-ASCII.
There is also 0% lying if one claims it's UTF-8.

It is not severe since, as you said, there are no non-ascii characters in the resulting string, but I think ruby should respect the set encoding.

Setting Encoding.default_internal (or something else) is not a guarantee
that all Strings will be in that encoding. Otherwise, it wouldn't be
called "default".

Regards, Martin.

---

Bug #7752: Rational/Float/Fixnum/Bignum .to_s.encoding is US-ASCII
https://bugs.ruby-lang.org/issues/7752#change-35742