[ruby-core:102908] [Ruby master Bug#17727] Unexpected syntax error when passing hash to **arg with kwarg

Issue #17727 has been updated by colintherobot (Colin Hart).

Description updated

Typos/readability

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Bug #17727: Unexpected syntax error when passing hash to **arg with kwarg
https://bugs.ruby-lang.org/issues/17727#change-90970

* Author: colintherobot (Colin Hart)
* Status: Open
* Priority: Normal
* ruby -v: ruby 2.6.5p114 (2019-10-01 revision 67812) [x86_64-darwin19]
* Backport: 2.5: UNKNOWN, 2.6: UNKNOWN, 2.7: UNKNOWN, 3.0: UNKNOWN
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Given a method that takes a kwarg and **arg

``` ruby
def foo(a:, **b)
   [a,b]
end 
```

If you call this method without deconstructing the hash passed to the second argument first it throws an error that I thought was maybe just an unhandled case. I would expect a message indicating you need to deconstruct the hash first. 

Instead it throws a syntax error:
``` ruby
foo(a: '1', {b: 2})
SyntaxError: unexpected ')', expecting =>
foo(a: '1', {b: 2})
                  ^
```

Passing case when you deconstruct the hash first:
``` ruby
foo(a: '1', **{b: 2})
=> ["1", {:b=>2}]
```

But wondering if there's something else going on because you get a different error when defining this case on multiple lines. If you're trying to run this in a repl environment it won't even let you complete the method call.

from repl:
``` ruby
foo(
  a: '1',
  {b: 2}
SyntaxError: unexpected '\n', expecting =>
```

passing case:
``` ruby
foo(
  a: '1',  
  **{b:1}
)  
=> ["1", {:b=>1}]
```


Attached is a ruby script to reproduce the above cases.


---Files--------------------------------
kwarg_bug.rb (291 Bytes)


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