Bug #17517: File.expand_path returns us-ascii when both arguments are ascii compat

• Status: Closed
• Assignee: -
• Target version: -
• Backport: 2.5: UNKNOWN, 2.6: UNKNOWN, 2.7: UNKNOWN, 3.0: UNKNOWN

[znz (Kazuhiro NISHIYAMA)]

Is this intentional?

p __dir__.encoding  #=> #<Encoding:UTF-8>
p 'hoge'.encoding   #=> #<Encoding:UTF-8>
p File.expand_path('hoge', __dir__).encoding #=> #<Encoding:US-ASCII>

% docker run -it --rm ghcr.io/ruby/all-ruby env ALL_RUBY_SINCE=ruby-1.9 ./all-ruby -e 'p File.expand_path("hoge".encode("utf-8"), "/".encode("utf-8")).encoding'
ruby-1.9.0-0        -e:1:in `encode': transcoding not supported (from ASCII-8BIT to UTF-8) (ArgumentError)
                    	from -e:1:in `<main>'
                exit 1
ruby-1.9.0-1        #<Encoding:ASCII-8BIT>
ruby-1.9.0-2        #<Encoding:US-ASCII>
...
ruby-1.9.1-p129     #<Encoding:US-ASCII>
ruby-1.9.1-p243     #<Encoding:UTF-8>
...
ruby-1.9.2-preview1 #<Encoding:UTF-8>
ruby-1.9.2-preview3 #<Encoding:US-ASCII>
...
ruby-3.0.0          #<Encoding:US-ASCII>

[byroot (Jean Boussier)]

I'm pretty sure it is intentional. That function calls rb_filesystem_encoding https://github.com/ruby/ruby/blob/d968829afa19c31e9461fd545cbd21250778ce6e/file.c#L3696

[duerst (Martin Dürst)]

• Subject changed from File.expand_path returns us-aascii when both arguments are ascii compat to File.expand_path returns us-ascii when both arguments are ascii compat

Fix a typo in subject.

[znz (Kazuhiro NISHIYAMA)]

Original question is __FILE__ and __dir__ are us-ascii only when loaded by relative_require.

% cat hoge.rb
p __FILE__.encoding
p __dir__.encoding
% cat require_relative.rb
require_relative 'hoge'
% ruby require_relative.rb
#<Encoding:US-ASCII>
#<Encoding:US-ASCII>
% cat require.rb
require './hoge'
% ruby require.rb
#<Encoding:UTF-8>
#<Encoding:UTF-8>

[nobu (Nobuyoshi Nakada)]

https://github.com/ruby/ruby/pull/4061

[nobu (Nobuyoshi Nakada)]

• Status changed from Open to Closed

Applied in changeset git|0d57d59933fb7b826bd0e20d84ed7f6d6636ac90.

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Keep encoding in the result of File.expand_path [Bug #17517]