Misc #20944
Updated by andrykonchin (Andrew Konchin) 5 months ago
The method Module#set_temporary_name` was introduced in Ruby 3.3. I've noticed a surprising behaviour when a temporary name is assigned to an anonymous module (that has nested non-anonymous modules) and then `Module#set_temporary_name` called with `nil`. The name of the nested module initially was fully qualified (e.g. `#<Module:0x000000010cc5a280>::N`) but after `set_temporary_name(nil)` call it becomes `nil`.
Example (from ruby/spec):
```ruby
m = Module.new
module m::N; end
m::N.name # => #<Module:0x...>::N
m::N.set_temporary_name("fake_name")
m::N.name # => "fake_name"
m::N.set_temporary_name(nil)
m::N.name # => nil <==== questionable quesitonable behaviour
```
I would expect a nested module name to have the initial value `#<Module:0x000000010cc5a280>::N` at the end.
The documentation states:
> If the given name is nil, the module becomes anonymous again.
So I would expect all the effects of setting a (non-nil) temporary name should be also rolled back.
Linked issue https://bugs.ruby-lang.org/issues/19521