WIP: handle nested blocks and non-top level blocks

lib/rubocop/cop/discourse/services/empty_lines_around_blocks.rb

@@ -18,17 +18,29 @@ class EmptyLinesAroundBlocks < Base
             )
           MATCHER
 
+          def_node_matcher :top_level_block?, <<~MATCHER
+            (block (send nil? _) ...)
+          MATCHER
+
           def on_class(node)
             return unless service_include?(node)
             @service = true
           end
 
           def on_block(node)
             return unless service?
+            return unless top_level_block?(node)
+            return if node.single_line?
+
             if missing_empty_lines?(node)
               add_offense(node, message: MSG) do |corrector|
                 if missing_empty_line_before?(node)
-                  corrector.insert_before(node.loc.expression, "\n")
+                  corrector.insert_before(
+                    node.loc.expression.adjust(
+                      begin_pos: -node.loc.expression.column
+                    ),
+                    "\n"
+                  )
                 end
                 if missing_empty_line_after?(node)
                   corrector.insert_after(node.loc.end, "\n")
@@ -48,11 +60,13 @@ def missing_empty_lines?(node)
           end
 
           def missing_empty_line_before?(node)
-            processed_source[node.loc.expression.line - 2].present?
+            processed_source[node.loc.expression.line - 2].present? &&
+              node.left_siblings.present?
           end
 
           def missing_empty_line_after?(node)
-            processed_source[node.loc.end.line].present?
+            processed_source[node.loc.end.line].present? &&
+              node.right_siblings.present?
           end
         end
       end