[ruby-core:108675] [Ruby master Bug#18793] Select and Find behave differently for hashes

Issue #18793 has been updated by jeremyevans0 (Jeremy Evans).


I don't think this is a bug.  The behavior difference is because `Hash#each` yields an array of `[key, value]` and not `key` and `value` separately, unlike `Hash#select`.

You can get the behavior you want by using explicit block variables:

```ruby
{ 1..10 => :a, 11 .. 20 => :b }.select { |k,| k === 5 }
{ 1..10 => :a, 11 .. 20 => :b }.find { |k,| k === 5 }
```

Your code could be made to work by adding a definition for `Hash#find` that yields `key` and `value` separately, but I don't think the backwards compatibility issues with such a change are worth it.

----------------------------------------
Bug #18793: Select and Find behave differently for hashes
https://bugs.ruby-lang.org/issues/18793#change-97716

* Author: brenogazzola (Breno Gazzola)
* Status: Open
* Priority: Normal
* ruby -v: 3.1.1
* Backport: 2.7: UNKNOWN, 3.0: UNKNOWN, 3.1: UNKNOWN
----------------------------------------
It seems that Hash implements select but not find, which uses the Enumerable version.

``` ruby
irb(main):009:0> { 1..10 => :a, 11 .. 20 => :b }.select { _1 === 12 }
=> {11..20=>:b}

irb(main):010:0> { 1..10 => :a, 11 .. 20 => :b }.find { _1 === 5 }
=> nil

irb(main):011:0> { 1..10 => :a, 11 .. 20 => :b }.select { p _1 }
1..10
11..20

irb(main):012:0> { 1..10 => :a, 11 .. 20 => :b }.find { p _1 }
[1..10, :a]
```

Expected Behavior:
I expected that both select and find return matches OR that neither select and find return matches

Current Behavior:
Select returns matches but find does not.



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