Disallow mixed usage of ... and */**

[Feature #19134]

compile.c

@@ -1832,6 +1832,7 @@ iseq_set_arguments(rb_iseq_t *iseq, LINK_ANCHOR *const optargs, const NODE *cons
 
         EXPECT_NODE("iseq_set_arguments", node_args, NODE_ARGS, COMPILE_NG);
 
+        body->param.flags.ruby2_keywords = args->ruby2_keywords;
         body->param.lead_num = arg_size = (int)args->pre_args_num;
         if (body->param.lead_num > 0) body->param.flags.has_lead = TRUE;
         debugs("  - argc: %d\n", body->param.lead_num);

node.h

@@ -462,6 +462,7 @@ struct rb_args_info {
 
     NODE *opt_args;
     unsigned int no_kwarg: 1;
+    unsigned int ruby2_keywords: 1;
     unsigned int forwarding: 1;
 
     VALUE imemo;

parse.y

@@ -943,6 +943,8 @@ static void numparam_pop(struct parser_params *p, NODE *prev_inner);
 #define idFWD_REST   '*'
 #define idFWD_KWREST idPow /* Use simple "**", as tDSTAR is "**arg" */
 #define idFWD_BLOCK  '&'
+#define idFWD_ALL    idDot3
+#define FORWARD_ARGS_WITH_RUBY2_KEYWORDS
 
 #define RE_OPTION_ONCE (1<<16)
 #define RE_OPTION_ENCODING_SHIFT 8
@@ -3150,7 +3152,8 @@ args		: arg_value
 		    }
 		| tSTAR
 		    {
-                        if (!local_id(p, idFWD_REST)) {
+                        if (!local_id(p, idFWD_REST) ||
+                            local_id(p, idFWD_ALL)) {
                             compile_error(p, "no anonymous rest parameter");
                         }
 		    /*%%%*/
@@ -3174,7 +3177,8 @@ args		: arg_value
 		    }
 		| args ',' tSTAR
 		    {
-                        if (!local_id(p, idFWD_REST)) {
+                        if (!local_id(p, idFWD_REST) ||
+                            local_id(p, idFWD_ALL)) {
                             compile_error(p, "no anonymous rest parameter");
                         }
 		    /*%%%*/
@@ -5601,7 +5605,11 @@ f_args		: f_arg ',' f_optarg ',' f_rest_arg opt_args_tail
 args_forward	: tBDOT3
 		    {
 		    /*%%%*/
+#ifdef FORWARD_ARGS_WITH_RUBY2_KEYWORDS
+			$$ = 0;
+#else
 			$$ = idFWD_KWREST;
+#endif
 		    /*% %*/
 		    /*% ripper: args_forward! %*/
 		    }
@@ -6044,7 +6052,8 @@ assoc		: arg_value tASSOC arg_value
 		    }
 		| tDSTAR
 		    {
-                        if (!local_id(p, idFWD_KWREST)) {
+                        if (!local_id(p, idFWD_KWREST) ||
+                            local_id(p, idFWD_ALL)) {
                             compile_error(p, "no anonymous keyword rest parameter");
                         }
 		    /*%%%*/
@@ -12574,6 +12583,12 @@ new_args(struct parser_params *p, NODE *pre_args, NODE *opt_args, ID rest_arg, N
 
     args->opt_args       = opt_args;
 
+#ifdef FORWARD_ARGS_WITH_RUBY2_KEYWORDS
+    args->ruby2_keywords = args->forwarding;
+#else
+    args->ruby2_keywords = 0;
+#endif
+
     p->ruby_sourceline = saved_line;
     nd_set_loc(tail, loc);
 
@@ -13256,9 +13271,7 @@ local_id(struct parser_params *p, ID id)
 static int
 check_forwarding_args(struct parser_params *p)
 {
-    if (local_id(p, idFWD_REST) &&
-        local_id(p, idFWD_KWREST) &&
-        local_id(p, idFWD_BLOCK)) return TRUE;
+    if (local_id(p, idFWD_ALL)) return TRUE;
     compile_error(p, "unexpected ...");
     return FALSE;
 }
@@ -13267,19 +13280,26 @@ static void
 add_forwarding_args(struct parser_params *p)
 {
     arg_var(p, idFWD_REST);
+#ifndef FORWARD_ARGS_WITH_RUBY2_KEYWORDS
     arg_var(p, idFWD_KWREST);
+#endif
     arg_var(p, idFWD_BLOCK);
+    arg_var(p, idFWD_ALL);
 }
 
 #ifndef RIPPER
 static NODE *
 new_args_forward_call(struct parser_params *p, NODE *leading, const YYLTYPE *loc, const YYLTYPE *argsloc)
 {
     NODE *rest = NEW_LVAR(idFWD_REST, loc);
+#ifndef FORWARD_ARGS_WITH_RUBY2_KEYWORDS
     NODE *kwrest = list_append(p, NEW_LIST(0, loc), NEW_LVAR(idFWD_KWREST, loc));
+#endif
     NODE *block = NEW_BLOCK_PASS(NEW_LVAR(idFWD_BLOCK, loc), loc);
     NODE *args = leading ? rest_arg_append(p, leading, rest, argsloc) : NEW_SPLAT(rest, loc);
+#ifndef FORWARD_ARGS_WITH_RUBY2_KEYWORDS
     args = arg_append(p, args, new_hash(p, kwrest, loc), loc);
+#endif
     return arg_blk_pass(args, block);
 }
 #endif

test/ruby/test_ast.rb

@@ -530,10 +530,10 @@ def test_argument_forwarding
     forwarding = lambda do |arg_str|
       node = RubyVM::AbstractSyntaxTree.parse("def a(#{arg_str}) end")
       node = node.children.last.children.last.children[1]
-      node ? [node.children[-4], node.children[-2].children, node.children[-1]] : []
+      node ? [node.children[-4], node.children[-2]&.children, node.children[-1]] : []
     end
 
-    assert_equal([:*, [:**], :&], forwarding.call('...'))
+    assert_equal([:*, nil, :&], forwarding.call('...'))
   end
 
   def test_ranges_numbered_parameter

test/ruby/test_syntax.rb

@@ -172,33 +172,11 @@ def f(a: nil, **); b(**) end
   end
 
   def test_argument_forwarding_with_anon_rest_kwrest_and_block
-    assert_separately([], "#{<<-"begin;"}\n#{<<-'end;'}")
-    begin;
-        def args(*args); args end
-        def kw(**kw); kw end
-        def block(&block); block end
-        def deconstruct(...); [args(*), kw(**), block(&)&.call] end
-        assert_equal([[], {}, nil], deconstruct)
-        assert_equal([[1], {}, nil], deconstruct(1))
-        assert_equal([[1, 2], {}, nil], deconstruct(1, 2))
-        assert_equal([[], {x: 1}, nil], deconstruct(x: 1))
-        assert_equal([[], {x: 1, y: 2}, nil], deconstruct(x: 1, y: 2))
-        assert_equal([[], {}, 1], deconstruct { 1 })
-        assert_equal([[1, 2], {x: 3, y: 4}, 5], deconstruct(1, 2, x: 3, y: 4) { 5 })
-    end;
-
-    assert_separately([], "#{<<-"begin;"}\n#{<<-'end;'}")
-    begin;
-        def deconstruct(*args, **kw, &block); [args, kw, block&.call] end
-        def deconstruct2(*, **, &); deconstruct(...); end
-        assert_equal([[], {}, nil], deconstruct2)
-        assert_equal([[1], {}, nil], deconstruct2(1))
-        assert_equal([[1, 2], {}, nil], deconstruct2(1, 2))
-        assert_equal([[], {x: 1}, nil], deconstruct2(x: 1))
-        assert_equal([[], {x: 1, y: 2}, nil], deconstruct2(x: 1, y: 2))
-        assert_equal([[], {}, 1], deconstruct2 { 1 })
-        assert_equal([[1, 2], {x: 3, y: 4}, 5], deconstruct2(1, 2, x: 3, y: 4) { 5 })
-    end;
+    assert_syntax_error("def f(*, **, &); g(...); end", /unexpected \.\.\./)
+    assert_syntax_error("def f(...); g(*); end", /no anonymous rest parameter/)
+    assert_syntax_error("def f(...); g(0, *); end", /no anonymous rest parameter/)
+    assert_syntax_error("def f(...); g(**); end", /no anonymous keyword rest parameter/)
+    assert_syntax_error("def f(...); g(x: 1, **); end", /no anonymous keyword rest parameter/)
   end
 
   def test_newline_in_block_parameters