From 6ae6b63aafbf64abd895aaeb84d80269a441a680 Mon Sep 17 00:00:00 2001
From: "Yukihiro \"Matz\" Matsumoto" <matz@ruby.or.jp>
Date: Thu, 22 Jun 2023 12:53:51 +0900
Subject: [PATCH] mruby-struct: add recursive inspect check instead of _inspect
 hack

---
 mrbgems/mruby-struct/mrblib/struct.rb | 29 -----------------
 mrbgems/mruby-struct/src/struct.c     | 45 +++++++++++++++++++++++++++
 mrbgems/mruby-struct/test/struct.rb   |  2 +-
 3 files changed, 46 insertions(+), 30 deletions(-)

diff --git a/mrbgems/mruby-struct/mrblib/struct.rb b/mrbgems/mruby-struct/mrblib/struct.rb
index f80c54518..20d9bde86 100644
--- a/mrbgems/mruby-struct/mrblib/struct.rb
+++ b/mrbgems/mruby-struct/mrblib/struct.rb
@@ -45,35 +45,6 @@ class Struct
     ary
   end
 
-  def _inspect(recur_list)
-    return "#<struct #{self.class}:...>" if recur_list[self.object_id]
-    recur_list[self.object_id] = true
-    name = self.class.to_s
-    if name[0] == "#"
-      str = "#<struct "
-    else
-      str = "#<struct #{name} "
-    end
-    buf = []
-    self.each_pair do |k,v|
-      buf.push k.to_s + "=" + v._inspect(recur_list)
-    end
-    str + buf.join(", ") + ">"
-  end
-
-  ##
-  # call-seq:
-  #   struct.to_s      -> string
-  #   struct.inspect   -> string
-  #
-  # Describe the contents of this struct in a string.
-  #
-  # 15.2.18.4.10(x)
-  #
-  def inspect
-    self._inspect({})
-  end
-
   ##
   # 15.2.18.4.11(x)
   #
diff --git a/mrbgems/mruby-struct/src/struct.c b/mrbgems/mruby-struct/src/struct.c
index 2b824320d..4f6dadcfb 100644
--- a/mrbgems/mruby-struct/src/struct.c
+++ b/mrbgems/mruby-struct/src/struct.c
@@ -634,6 +634,49 @@ mrb_struct_values_at(mrb_state *mrb, mrb_value self)
   return mrb_get_values_at(mrb, self, RSTRUCT_LEN(self), argc, argv, struct_aref_int);
 }
 
+/*
+ * call-seq:
+ *    struct.to_s    -> string
+ *    struct.inspect -> string
+ *
+ * Returns a string representation of Data
+ */
+static mrb_value
+mrb_struct_to_s(mrb_state *mrb, mrb_value self)
+{
+  mrb_value members, ret, cname;
+  mrb_value *mems;
+  mrb_int mlen;
+
+  mrb->c->ci->mid = MRB_SYM(inspect);
+  ret = mrb_str_new_lit(mrb, "#<struct ");
+  int ai = mrb_gc_arena_save(mrb);
+  cname = mrb_class_path(mrb, mrb_class_real(mrb_class(mrb, self)));
+  if (!mrb_nil_p(cname)) {
+    mrb_str_cat_str(mrb, ret, cname);
+    mrb_str_cat_lit(mrb, ret, " ");
+  }
+  if (mrb_inspect_recursive_p(mrb, self)) {
+    mrb_str_cat_lit(mrb, ret, "...>");
+    return ret;
+  }
+  members = struct_members(mrb, self);
+  mlen = RARRAY_LEN(members);
+  mems = RARRAY_PTR(members);
+  for (mrb_int i=0; i<mlen; i++) {
+    mrb_int len;
+    const char *name = mrb_sym_name_len(mrb, mrb_symbol(mems[i]), &len);
+    if (i>0) mrb_str_cat_lit(mrb, ret, ", ");
+    mrb_str_cat(mrb, ret, name, len);
+    mrb_str_cat_lit(mrb, ret, "=");
+    mrb_str_cat_str(mrb, ret, mrb_inspect(mrb, mrb_ary_ref(mrb, self, i)));
+    mrb_gc_arena_restore(mrb, ai);
+  }
+  mrb_str_cat_lit(mrb, ret, ">");
+
+  return ret;
+}
+
 /*
  *  A <code>Struct</code> is a convenient way to bundle a number of
  *  attributes together, using accessor methods, without having to write
@@ -665,6 +708,8 @@ mrb_mruby_struct_gem_init(mrb_state* mrb)
   mrb_define_method(mrb, st,       "initialize",      mrb_struct_initialize,  MRB_ARGS_ANY());  /* 15.2.18.4.8  */
   mrb_define_method(mrb, st,       "initialize_copy", mrb_struct_init_copy,   MRB_ARGS_REQ(1)); /* 15.2.18.4.9  */
   mrb_define_method(mrb, st,       "eql?",            mrb_struct_eql,         MRB_ARGS_REQ(1)); /* 15.2.18.4.12(x)  */
+  mrb_define_method(mrb, st,       "to_s",            mrb_struct_to_s,        MRB_ARGS_NONE()); /* 15.2.18.4.11(x) */
+  mrb_define_method(mrb, st,       "inspect",         mrb_struct_to_s,        MRB_ARGS_NONE()); /* 15.2.18.4.10(x) */
 
   mrb_define_method(mrb, st,       "size",            mrb_struct_len,         MRB_ARGS_NONE());
   mrb_define_method(mrb, st,       "length",          mrb_struct_len,         MRB_ARGS_NONE());
diff --git a/mrbgems/mruby-struct/test/struct.rb b/mrbgems/mruby-struct/test/struct.rb
index db0fa56d8..384a92063 100644
--- a/mrbgems/mruby-struct/test/struct.rb
+++ b/mrbgems/mruby-struct/test/struct.rb
@@ -119,7 +119,7 @@ assert('struct inspect') do
   c = Struct.new(:m1, :m2, :m3, :m4, :m5, :recur)
   cc = c.new(1,2,3,4,5,nil)
   cc.recur = cc
-  assert_equal "#<struct m1=1, m2=2, m3=3, m4=4, m5=5, recur=#<struct #{cc.class}:...>>", cc.inspect
+  assert_equal "#<struct m1=1, m2=2, m3=3, m4=4, m5=5, recur=#<struct ...>>", cc.inspect
 end
 
 assert('Struct#length, Struct#size') do