Make defined? for op asgn expressions to constants use "assignment"

Previously, it used "expression", as that was the default.  However,
op asgn expressions to constants use the NODE_OP_CDECL, so recognize
that node type as assignement.

Fixes [Bug #20111]

1 files changed, 1 insertions, 0 deletions

diff --git a/compile.c b/compile.c
index 3822646c0e..6e0456af35 100644
--- a/compile.c
+++ b/compile.c
@@ -5951,6 +5951,7 @@ defined_expr0(rb_iseq_t *iseq, LINK_ANCHOR *const ret,
       case NODE_IASGN:
       case NODE_CDECL:
       case NODE_CVASGN:
+      case NODE_OP_CDECL:
         expr_type = DEFINED_ASGN;
         break;
     }