fix: fix bug method calling with anonymous block arg

ref: #332

Author: kzkn

lib/rufo/formatter.rb

@@ -1083,7 +1083,7 @@ def visit_call_at_paren(node, args)
       # Check if there's a block arg and if the call ends with hash key/values
       if args_node[0] == :args_add_block
         _, args, block_arg = args_node
-        want_trailing_comma = !block_arg
+        want_trailing_comma = block_arg_type(block_arg) == :no_arg
         if args.is_a?(Array) && (last_arg = args.last) && last_arg.is_a?(Array) &&
            last_arg[0].is_a?(Symbol) && last_arg[0] != :bare_assoc_hash
           want_trailing_comma = false
@@ -1475,11 +1475,7 @@ def visit_call_args(node)
       visit_comma_separated_list args
     end
 
-    # block_arg will be...
-    #  - named => node
-    #  - anonymous => nil
-    #  - no arg => false
-    if block_arg || block_arg.nil?
+    if block_arg_type(block_arg) != :no_arg
       skip_space_or_newline
 
       if comma?
@@ -4207,4 +4203,15 @@ def node_line(node, beginning: true)
       node[2][0]
     end
   end
+
+  def block_arg_type(node)
+    case node
+    when nil
+      :anonymous
+    when false
+      :no_arg
+    else
+      node
+    end
+  end
 end

spec/lib/rufo/formatter_source_specs/3.1/method_definition.rb.spec

@@ -61,3 +61,20 @@ end
 def foo(a: 1,
         &)
 end
+
+#~# ORIGINAL issue_332
+
+def foo(&)
+  hoge(
+      **a,
+  &
+  )
+  end
+
+#~# EXPECTED
+def foo(&)
+  hoge(
+    **a,
+    &
+  )
+end