Bug #10815: Dir.foreach in block form does not allow encoding

• Status: Rejected
• Assignee: -
• Target version: -
• ruby -v: ruby 2.2.0p0 (2014-12-25 revision 49005) [i386-mswin32_120]
• Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN

[djberg96 (Daniel Berger)]

It doesn't appear that Dir.foreach{} allows an encoding:

enc = Encoding::UTF_16LE

# Without a block, works ok
p Dir.foreach(Dir.pwd)      # => Enumerator
p Dir.foreach(Dir.pwd, enc) # => Enumerator

# With a block, fails if more than 1 argument is passed
p Dir.foreach(Dir.pwd){ }      # => nil
p Dir.foreach(Dir.pwd, enc){ } # => ArgumentError

[djberg96 (Daniel Berger)]

I should also note that the method does not appear to do any sort of type or arity checking. I'm not sure if that's intentional.

Dir.foreach(Dir.pwd, true, false, nil) # => no error

[nobu (Nobuyoshi Nakada)]

• Status changed from Open to Rejected

Encoding is a keyword argument.

Dir.foreach( dirname, encoding: enc ) {| filename | block }  -> nil

Dir.foreach(Dir.pwd, true, false, nil) # => no error

It returns an enumerator.

Dir.foreach( dirname )                                       -> an_enumerator

You'll see an ArgumentError when enumerating it.

[djberg96 (Daniel Berger)]

Ok, but that seems a strange way to declare the function prototype. Compare that with Dir.entries, which does give you an error if you pass the wrong number of arguments.

[nobu (Nobuyoshi Nakada)]

Dir.entries doesn't return an enumerator.

[djberg96 (Daniel Berger)]

I guess I'm not sure at what point or why the return type started governing function prototypes, but ok.