Issue #7148 has been reported by Glass_saga (Masaki Matsushita).

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Feature #7148: Improved Tempfile w/o DelegateClass
https://bugs.ruby-lang.org/issues/7148

Author: Glass_saga (Masaki Matsushita)
Status: Open
Priority: Normal
Assignee: 
Category: lib
Target version: 


I propose improved Tempfile without DelegateClass().
Present Tempfile has following problems.

1) confusing inspect

t = Tempfile.new("foo") #=> #<File:/tmp/foo20121012-6762-12w11to>
t.is_a? File #=> false

2) #dup doesn't duplicate IO

t = Tempfile.new("foo")
t.dup.close
t.read #=> IOError: closed stream

3) finalizer performs unlink even when it has been duplicated

t = Tempfile.new("foo")
path = t.path #=> "/tmp/foo20121012-7533-1q537gq"
File.exist? path #=> true
tt = t.dup
t = nil
GC.start
File.exist? path #=> false

I think these problems caused by using DelegateClass().
Therefore, I made a patch to resolve the problems.
The patched Tempfile class is a subclass of File.


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