Layout/ClassStructure syntax error / cloberring error auto-corrections

[marcandre]

Layout/ClassStructure has a bad algorithm for moving code with respect to empty lines before/after. Look for +1 in the code.

Heredocs

Looks like the cop assumes that heredocs are always followed by a empty line

      class Foo
        attr_reader :foo
        CONSTANT = <<~EOS
        ^^^^^^^^^^^^^^^^^ `constants` is supposed to appear [...]
          abc
        EOS
      end

gets auto-corrected to:

      class Foo
        CONSTANT = <<~EOS
          abc
        EOS
        attr_reader :fooend

If the config's order is switched, then

        class Foo
          CONSTANT = <<~EOS
            #{str}
          EOS
          attr_reader :foo
          ^^^^^^^^^^^^^ [...]
        end

generates a cloberring error.

Defs

Defs (except initialize??) can create issues when not separated with empty lines. E.g.:

        class Foo
          private
          def foo
          end
          public
          def bar
          ^^^^^^^ [...]
          end
        end

gets auto-corrected to:

        class Foo
          public
          def bar
          ^^^^^^^ [...]
          end
          private
          def foo
          endend

In general, it should have been clear that to swap two blocks of code and keep good empty lines is not possible with a single "cut" and "paste", but that is what the current code is attempting.

Noticed in my refactor, I'll handle it.