[ruby/syntax_suggest] Rollback comment indentation behavior

Originally I fixed https://github.com/ruby/syntax_suggest/pull/177 by making the process of comment removal indentation aware. The next commit is the more general fix and means we don't need to carry that additional logic/overhead.

Also: Update syntax via linter

lib/syntax_suggest/clean_document.rb

@@ -155,10 +155,11 @@ module SyntaxSuggest
     #    ).to eq(2)
     #
     def clean_sweep(source:)
+      # Match comments, but not HEREDOC strings with #{variable} interpolation
+      # https://rubular.com/r/HPwtW9OYxKUHXQ
       source.lines.map do |line|
-        if line.match?(/^\s*#([^{].*)?$/) # https://rubular.com/r/LLE10D8HKMkJvs
-          whitespace = /^(?<whitespace>\s*)#([^{].*)?$/.match(line).named_captures["whitespace"] || ""
-          whitespace + $/
+        if line.match?(/^\s*#([^{].*|)$/)
+          $/
         else
           line
         end

lib/syntax_suggest/code_line.rb

@@ -48,10 +48,10 @@ module SyntaxSuggest
       strip_line = line.dup
       strip_line.lstrip!
 
-      if (@empty = strip_line.empty?)
-        @indent = line.length - 1 # Newline removed from strip_line is not "whitespace"
+      @indent = if (@empty = strip_line.empty?)
+        line.length - 1 # Newline removed from strip_line is not "whitespace"
       else
-        @indent = line.length - strip_line.length
+        line.length - strip_line.length
       end
 
       set_kw_end

spec/syntax_suggest/unit/block_expand_spec.rb

@@ -28,9 +28,9 @@ module SyntaxSuggest
       block = expansion.expand_neighbors(block)
 
       expect(block.to_s).to eq(<<~EOM.indent(2))
-          def bark       # index 1
+        def bark       # index 1
 
-          end            # index 3
+        end            # index 3
       EOM
     end
 

spec/syntax_suggest/unit/clean_document_spec.rb

@@ -72,7 +72,6 @@ module SyntaxSuggest
       EOM
     end
 
-
     it "joins multi-line chained methods when separated by comments" do
       source = <<~EOM
         User.
@@ -114,7 +113,7 @@ module SyntaxSuggest
       lines = CleanDocument.new(source: source).lines
       expect(lines[0].to_s).to eq($/)
       expect(lines[1].to_s).to eq('puts "what"' + $/)
-      expect(lines[2].to_s).to eq('  ' + $/)
+      expect(lines[2].to_s).to eq($/)
     end
 
     it "trailing slash: does not join trailing do" do