vm_args.c: wrap symbol ifunc

* vm_args.c (args_setup_block_parameter): wrap a symbol in ifunc
  by a proc as a block parameter.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@52056 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

internal.h

@@ -1110,6 +1110,7 @@ VALUE rb_external_str_with_enc(VALUE str, rb_encoding *eenc);
 #define is_broken_string(str) (rb_enc_str_coderange(str) == ENC_CODERANGE_BROKEN)
 size_t rb_str_memsize(VALUE);
 VALUE rb_sym_proc_call(VALUE args, VALUE sym, int argc, const VALUE *argv, VALUE passed_proc);
+VALUE rb_sym_to_proc(VALUE sym);
 
 /* struct.c */
 VALUE rb_struct_init_copy(VALUE copy, VALUE s);

string.c

@@ -8946,6 +8946,7 @@ rb_sym_proc_call(VALUE args, VALUE sym, int argc, const VALUE *argv, VALUE passe
     return rb_funcall_with_block(obj, (ID)sym, argc - 1, argv + 1, passed_proc);
 }
 
+#define sym_to_proc rb_sym_to_proc
 /*
  * call-seq:
  *   sym.to_proc
@@ -8955,7 +8956,7 @@ rb_sym_proc_call(VALUE args, VALUE sym, int argc, const VALUE *argv, VALUE passe
  *   (1..3).collect(&:to_s)  #=> ["1", "2", "3"]
  */
 
-static VALUE
+VALUE
 sym_to_proc(VALUE sym)
 {
     static VALUE sym_proc_cache = Qfalse;

test/ruby/test_symbol.rb

@@ -140,6 +140,13 @@ class TestSymbol < Test::Unit::TestCase
     end;
   end
 
+  def test_to_proc_arg
+    assert_separately([], <<-"end;", timeout: 5.0)
+      def (obj = Object.new).proc(&b) b; end
+      assert_same(:itself.to_proc, obj.proc(&:itself))
+    end;
+  end
+
   def test_call
     o = Object.new
     def o.foo(x, y); x + y; end

vm_args.c

@@ -478,6 +478,10 @@ args_setup_block_parameter(rb_thread_t *th, struct rb_calling_info *calling, VAL
 	    GetProcPtr(blockval, proc);
 	    calling->blockptr = &proc->block;
 	}
+	else if (RUBY_VM_IFUNC_P(blockptr->proc)) {
+	    const ID mid = (ID)((struct vm_ifunc *)blockptr->proc)->data;
+	    blockval = rb_sym_to_proc(ID2SYM(mid));
+	}
 	else {
 	    blockval = blockptr->proc;
 	}