Check for : @ and $ before 'do'

[graceful-potato]

This is a fix for #658
First I just wanted to check that there is a start of line or space char before do keyword, but there is some weird cases where you can put do right after the method name without space:

def +
  yield "test"
end

self.+do |e|
  e.upcase
end

I am pretty sure this will work for any of these methods: +, -, *, /, ^, %, &, |
Blocks are rarely used with them and blocks without space between method name and do I think almost never.
So I am not sure what is better.

[codecov]

Codecov Report

Merging #660 into master will not change coverage.
The diff coverage is n/a.

@@          Coverage Diff           @@
##           master    #660   +/-   ##
======================================
  Coverage    5.08%   5.08%           
======================================
  Files          10      10           
  Lines         118     118           
  Branches       20      20           
======================================
  Hits            6       6           
  Misses        112     112           

Flag	Coverage Δ
#language_server_ruby	5.08% <ø> (ø)

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[wingrunr21]

I'd just make it whatever is going to be right most of the time.

Part of my radio silence on this is converting things over to the tree-sitter query support. That should open up the semantic highlighting API that VSCode recently shipped which will hopefully cover the rest of these edge cases.

[graceful-potato]

I heard about tree sitter, but I dont know much about it. This is just a quick fix in standard grammar file.

[Nowaker]

Thank you!