[Feature #19370] Prohibit nesting anonymous parameter forwarding

nobu · nobu · commit a9f096183170 · 2023-12-25T14:44:04.000+09:00
diff --git a/parse.y b/parse.y
@@ -15009,6 +15009,8 @@ add_forwarding_args(struct parser_params *p)
 static void
 forwarding_arg_check(struct parser_params *p, ID arg, ID all, const char *var)
 {
+    bool conflict = false;
+
     struct vtable *vars, *args;
 
     vars = p->lvtbl->vars;
@@ -15017,6 +15019,7 @@ forwarding_arg_check(struct parser_params *p, ID arg, ID all, const char *var)
     while (vars && !DVARS_TERMINAL_P(vars->prev)) {
         vars = vars->prev;
         args = args->prev;
+        conflict |= (vtable_included(args, arg) && !(all && vtable_included(args, all)));
     }
 
     bool found = false;
@@ -15032,6 +15035,9 @@ forwarding_arg_check(struct parser_params *p, ID arg, ID all, const char *var)
     if (!found) {
         compile_error(p, "no anonymous %s parameter", var);
     }
+    else if (conflict) {
+        compile_error(p, "anonymous %s parameter is also used within block", var);
+    }
 }
 
 #ifndef RIPPER
diff --git a/test/ruby/test_syntax.rb b/test/ruby/test_syntax.rb
@@ -76,6 +76,7 @@ def test_script_lines_encoding
 
   def test_anonymous_block_forwarding
     assert_syntax_error("def b; c(&); end", /no anonymous block parameter/)
+    assert_syntax_error("def b(&) ->(&) {c(&)} end", /anonymous block parameter is also used/)
     assert_separately([], "#{<<-"begin;"}\n#{<<-'end;'}")
     begin;
       def b(&); c(&) end
@@ -143,6 +144,9 @@ def all_kwrest(arg1, arg2, *rest, post1, post2, kw1: 1, kw2: 2, okw1:, okw2:, **
   def test_anonymous_rest_forwarding
     assert_syntax_error("def b; c(*); end", /no anonymous rest parameter/)
     assert_syntax_error("def b; c(1, *); end", /no anonymous rest parameter/)
+    assert_syntax_error("def b(*) ->(*) {c(*)} end", /anonymous rest parameter is also used/)
+    assert_syntax_error("def b(a, *) ->(*) {c(1, *)} end", /anonymous rest parameter is also used/)
+    assert_syntax_error("def b(*) ->(a, *) {c(*)} end", /anonymous rest parameter is also used/)
     assert_separately([], "#{<<-"begin;"}\n#{<<-'end;'}")
     begin;
       def b(*); c(*) end
@@ -156,6 +160,9 @@ def d(*); b(*, *) end
   def test_anonymous_keyword_rest_forwarding
     assert_syntax_error("def b; c(**); end", /no anonymous keyword rest parameter/)
     assert_syntax_error("def b; c(k: 1, **); end", /no anonymous keyword rest parameter/)
+    assert_syntax_error("def b(**) ->(**) {c(**)} end", /anonymous keyword rest parameter is also used/)
+    assert_syntax_error("def b(k:, **) ->(**) {c(k: 1, **)} end", /anonymous keyword rest parameter is also used/)
+    assert_syntax_error("def b(**) ->(k:, **) {c(**)} end", /anonymous keyword rest parameter is also used/)
     assert_separately([], "#{<<-"begin;"}\n#{<<-'end;'}")
     begin;
       def b(**); c(**) end

Original file line number	Diff line number	Diff line change
`@@ -15009,6 +15009,8 @@ add_forwarding_args(struct parser_params *p)`
`15009`	`15009`	`static void`
`15010`	`15010`	`forwarding_arg_check(struct parser_params p, ID arg, ID all, const char var)`
`15011`	`15011`	`{`
	`15012`	`+ bool conflict = false;`
	`15013`	`+`
`15012`	`15014`	`struct vtable vars, args;`
`15013`	`15015`
`15014`	`15016`	`vars = p->lvtbl->vars;`
`@@ -15017,6 +15019,7 @@ forwarding_arg_check(struct parser_params p, ID arg, ID all, const char var)`
`15017`	`15019`	`while (vars && !DVARS_TERMINAL_P(vars->prev)) {`
`15018`	`15020`	`vars = vars->prev;`
`15019`	`15021`	`args = args->prev;`
	`15022`	`+ conflict \|= (vtable_included(args, arg) && !(all && vtable_included(args, all)));`
`15020`	`15023`	`}`
`15021`	`15024`
`15022`	`15025`	`bool found = false;`
`@@ -15032,6 +15035,9 @@ forwarding_arg_check(struct parser_params p, ID arg, ID all, const char var)`
`15032`	`15035`	`if (!found) {`
`15033`	`15036`	`compile_error(p, "no anonymous %s parameter", var);`
`15034`	`15037`	`}`
	`15038`	`+ else if (conflict) {`
	`15039`	`+ compile_error(p, "anonymous %s parameter is also used within block", var);`
	`15040`	`+ }`
`15035`	`15041`	`}`
`15036`	`15042`
`15037`	`15043`	`#ifndef RIPPER`