Make super in instance_eval in method in module raise TypeError

This makes behavior the same as super in instance_eval in method
in class.  The reason this wasn't implemented before is that
there is a check to determine if the self in the current context
is of the expected class, and a module itself can be included
in multiple classes, so it doesn't have an expected class.

Implementing this requires giving iclasses knowledge of which
class created them, so that super call in the module method
knows the expected class for super calls.  This reference
is called includer, and should only be set for iclasses.

Note that the approach Ruby uses in this check is not robust. If
you instance_eval another object of the same class and call super,
instead of an TypeError, you get super called with the
instance_eval receiver instead of the method receiver.  Truly
fixing super would require keeping a reference to the super object
(method receiver) in each frame where scope has changed, and using
that instead of current self when calling super.

Fixes [Bug #11636]

1 files changed, 8 insertions, 0 deletions

diff --git a/internal.h b/internal.h
index 374db5c0a4..3bd95c2c25 100644
--- a/internal.h
+++ b/internal.h
@@ -1039,6 +1039,7 @@ struct rb_classext_struct {
     const VALUE origin_;
     const VALUE refined_class;
     rb_alloc_func_t allocator;
+    const VALUE includer;
 };
 
 typedef struct rb_classext_struct rb_classext_t;
@@ -1078,6 +1079,7 @@ int rb_singleton_class_internal_p(VALUE sklass);
 #else
 # define RCLASS_SERIAL(c) (RCLASS_EXT(c)->class_serial)
 #endif
+#define RCLASS_INCLUDER(c) (RCLASS_EXT(c)->includer)
 
 #define RCLASS_CLONED     FL_USER6
 #define RICLASS_IS_ORIGIN FL_USER5
@@ -1090,6 +1092,12 @@ RCLASS_SET_ORIGIN(VALUE klass, VALUE origin)
     if (klass != origin) FL_SET(origin, RICLASS_IS_ORIGIN);
 }
 
+static inline void
+RCLASS_SET_INCLUDER(VALUE iclass, VALUE klass)
+{
+    RB_OBJ_WRITE(iclass, &RCLASS_INCLUDER(iclass), klass);
+}
+
 #undef RCLASS_SUPER
 static inline VALUE
 RCLASS_SUPER(VALUE klass)