parse.y: lparen_arg statement

* parse.y (primary): allow parenthesised statement as a method
  argument.  [Feature #12686]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@55965 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,8 @@
+Fri Aug 19 11:39:06 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* parse.y (primary): allow parenthesised statement as a method
+	  argument.  [Feature #12686]
+
 Fri Aug 19 09:12:45 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* vm.c (vm_set_main_stack): TOPLEVEL_BINDING must be built.

parse.y

@@ -2659,7 +2659,7 @@ primary		: literal
 			$<val>1 = cmdarg_stack;
 			CMDARG_SET(0);
 		    }
-		  expr {SET_LEX_STATE(EXPR_ENDARG);} rparen
+		  stmt {SET_LEX_STATE(EXPR_ENDARG);} rparen
 		    {
 			CMDARG_SET($<val>1);
 		    /*%%%*/

test/ruby/test_syntax.rb

@@ -827,6 +827,11 @@ eom
     end
   end
 
+  def test_parenthesised_statement_argument
+    assert_syntax_error("foo(bar rescue nil)", /unexpected modifier_rescue/)
+    assert_valid_syntax("foo (bar rescue nil)")
+  end
+
   private
 
   def not_label(x) @result = x; @not_label ||= nil end