[ruby-core:51649] [ruby-trunk - Bug #7522] Non-core "Type()" Kernel methods return new objects

Issue #7522 has been updated by ko1 (Koichi Sasada).

Category set to core
Assignee set to mame (Yusuke Endoh)
Target version set to 2.0.0

I'm not sure who should take this issue.

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Bug #7522: Non-core "Type()" Kernel methods return new objects
https://bugs.ruby-lang.org/issues/7522#change-35610

Author: jballanc (Joshua Ballanco)
Status: Open
Priority: Normal
Assignee: mame (Yusuke Endoh)
Category: core
Target version: 2.0.0
ruby -v: 2.0.0-preview1


The methods Array(), String(), Float(), Integer(), Hash(), and Rational() all return their argument when the argument is already an instance of the type in question. For example:

a = []
a.equal? Array(a) #=> true

However, the similar methods Pathname(), BigDecimal(), and Complex() do not do this:

p = Pathname.new('/tmp')
p.equal? Pathname(p) #=> false

I had the impression that the "Type()" methods were intended as "safe" coercion methods. That is, if no type conversion is required, then the system is left unchanged (and no new objects are created). The attached patch fixes the three methods mentioned above to adhere to this same invariant.


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