Remove (or disable) Style/BracesAroundHashParameters

[pocke]

Since Ruby 2.7, the existence of curly braces on the last argument has meaning.

It means, the following codes have different meanings.

foo(x: 1) # x: 1 is a keyword argument
foo({x: 1}) # {x: 1} is a hash

There are the correct pairs of method definitions and method calls.

def foo(x: 1)
end
foo(x: 1)

def foo(hash)
end
foo({x: 1})

For more detail https://www.ruby-lang.org/en/news/2019/12/12/separation-of-positional-and-keyword-arguments-in-ruby-3-0/

So I propose removing the cop. I think we should disable the cop by default at least.

---

Expected behavior

Remove or disable the cop.

Actual behavior

It's available.

Steps to reproduce the problem

nothing

RuboCop version

master

[koic]

I agree with @pocke. I think this proposal makes sense for future Ruby 3. And I think the cop should be removed to smooth the transition from Ruby 2 to Ruby 3.

[bbatsov]

Yeah, agreed. Let's remove it.

[deivid-rodriguez]

Hi @pocke!

Currently the HashSyntax cop also warns foo(x: 1) invocations if configured with the hash rockets style. I'm guessing these offences should also be removed from the Style/HashSyntax cop, right?

[sandstrom]

Agree with what @deivid-rodriguez said, it would be awesome if Style/HashSyntax configured with hash_rockets wouldn't complain about keyword arguments, e.g. foo(x: 1).

Also, see #1451