ruby.git/test/prism/errors/def_with_optional_splat.txt, branch v4.0.3 The Ruby Programming Language [ruby/prism] For these special cases, there exists no optional argument type. Since a endless method is started with `=`, there was ambiguity here. We have to simply reject these in all cases. 2025-10-08T13:04:57+00:00 Earlopain 14981592+Earlopain@users.noreply.github.com 2025-10-08T12:54:14+00:00 b8f8d646a64f883652b44780c4174a85f98d1c82 This adds a new error for the following reason: * `def foo arg = nil` is interpreted as a normal method call with optional `arg` without matching `end` * `def foo *arg = nil; end` is interpreted as a endless method call that has body `nil` with extraneous `end` `def foo *arg = nil` is somewhere inbetween and I don't know how to otherwise indicate the error. Now the second case above also shows the newly added error message. Fixes [Bug #21623] https://github.com/ruby/prism/commit/e1910d4492 
This adds a new error for the following reason:
* `def foo arg = nil` is interpreted as a normal method call with optional `arg` without matching `end`
* `def foo *arg = nil; end` is interpreted as a endless method call that has body `nil` with extraneous `end`

`def foo *arg = nil` is somewhere inbetween and I don't know how to otherwise indicate the error.
Now the second case above also shows the newly added error message.

Fixes [Bug #21623]

https://github.com/ruby/prism/commit/e1910d4492