enum.c: respect method visibility

* enum.c (ary_inject_op): should respect method visibility, do not
  optimize uncallable method.  [ruby-core:81349] [Bug #13592]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@58871 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

2 files changed, 23 insertions, 3 deletions

diff --git a/enum.c b/enum.c
index 4e14e82090..674c3ccfb0 100644
--- a/enum.c
+++ b/enum.c
@@ -678,8 +678,9 @@ ary_inject_op(VALUE ary, VALUE init, VALUE op)
 
     id = SYM2ID(op);
     if (id == idPLUS) {
-        if ((FIXNUM_P(v) || RB_TYPE_P(v, T_BIGNUM)) &&
-             rb_method_basic_definition_p(rb_cInteger, idPLUS)) {
+	if (RB_INTEGER_TYPE_P(v) &&
+	    rb_method_basic_definition_p(rb_cInteger, idPLUS) &&
+	    rb_obj_respond_to(v, idPLUS, FALSE)) {
             n = 0;
             for (; i < RARRAY_LEN(ary); i++) {
                 e = RARRAY_AREF(ary, i);
@@ -705,7 +706,7 @@ ary_inject_op(VALUE ary, VALUE init, VALUE op)
         }
     }
     for (; i < RARRAY_LEN(ary); i++) {
-        v = rb_funcall(v, id, 1, RARRAY_AREF(ary, i));
+        v = rb_funcallv_public(v, id, 1, &RARRAY_CONST_PTR(ary)[i]);
     }
     return v;
 }
diff --git a/test/ruby/test_enum.rb b/test/ruby/test_enum.rb
index 86998eef60..57616791bb 100644
--- a/test/ruby/test_enum.rb
+++ b/test/ruby/test_enum.rb
@@ -234,6 +234,25 @@ class TestEnumerable < Test::Unit::TestCase
     end;
   end
 
+  def test_inject_array_op_private
+    assert_separately([], "#{<<~"end;"}\n""end")
+    all_assertions_foreach("", *%i[+ * / - %]) do |op|
+      bug = '[ruby-core:81349] [Bug #13592] should respect visibility'
+      assert_raise_with_message(NoMethodError, /private method/, bug) do
+        begin
+          Integer.class_eval do
+            private op
+          end
+          [1,2,3].inject(op)
+        ensure
+          Integer.class_eval do
+            public op
+          end
+        end
+      end
+    end;
+  end
+
   def test_partition
     assert_equal([[1, 3, 1], [2, 2]], @obj.partition {|x| x % 2 == 1 })
     cond = ->(x, i) { x % 2 == 1 }