From: "Eregon (Benoit Daloze) via ruby-core" <ruby-core@...>
Date: 2022-12-26T14:39:13+00:00
Subject: [ruby-core:111445] [Ruby master Bug#19259] `Data#with` doesn't call `initialize` nor `initialize_copy`

Issue #19259 has been updated by Eregon (Benoit Daloze).


zverok (Victor Shepelev) wrote in #note-6:
> Intuitively, I don't think so, but I fail to find good logical arguments :) 
> (We can, for example, note that `with` is some `Data`-specific and fancy copying/duplication method, and `dup`/`clone` don't invoke `.new`)

Yeah, I think it's uncommon to call `.new` dynamically for core classes so probably no need here.
It would matter if someone defined a custom `new`, but our expectation with Data is that people define a custom initialize and not a custom new.

----------------------------------------
Bug #19259: `Data#with` doesn't call `initialize` nor `initialize_copy`
https://bugs.ruby-lang.org/issues/19259#change-100816

* Author: ko1 (Koichi Sasada)
* Status: Open
* Priority: Normal
* Backport: 2.7: UNKNOWN, 3.0: UNKNOWN, 3.1: UNKNOWN
----------------------------------------
`Data#with` doesn't call `initialize` nor `initialize_copy`.
It is confirmation request.

```ruby
class P < Data.define(:x, :y)
  def initialize_copy(...)
    p :initialize_copy
    super
  end

  def initialize(...)
    p :initialize
    super
  end
end

pt = P.new(1, 2)
#=> :initialize
pt.clone
#=> :initialize_copy
pt.dup
#=> :initialize_copy
pt.with(x: 10)
#=> N/A
```

For example, if an author of `P` add validation code, `#with` skips it.



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