* array.c (rb_ary_equal): a == b is true when b is non T_ARRAY

  object, if b has "to_ary" and b == a.

* hash.c (rb_hash_equal): a == b is true when b is non T_HASH
  object, if b has "to_hash" and b == a.

* string.c (rb_str_equal): a == b is true when b is non T_STRING
  object, if b has "to_str" and b == a.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@3442 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 6 insertions, 1 deletions

diff --git a/hash.c b/hash.c
index d52ef7a40c..81b882ed14 100644
--- a/hash.c
+++ b/hash.c
@@ -866,7 +866,12 @@ rb_hash_equal(hash1, hash2)
     struct equal_data data;
 
     if (hash1 == hash2) return Qtrue;
-    if (TYPE(hash2) != T_HASH) return Qfalse;
+    if (TYPE(hash2) != T_HASH) {
+	if (!rb_respond_to(hash2, rb_intern("to_hash"))) {
+	    return Qfalse;
+	}
+	return rb_equal(hash2, hash1);
+    }
     if (RHASH(hash1)->tbl->num_entries != RHASH(hash2)->tbl->num_entries)
 	return Qfalse;
     if (!(rb_equal(RHASH(hash1)->ifnone, RHASH(hash2)->ifnone) &&