From 1e52dde82af10f2a2ec648b34dce30bec4154245 Mon Sep 17 00:00:00 2001
From: Kevin Newton <kddnewton@gmail.com>
Date: Mon, 16 Sep 2024 11:14:31 -0400
Subject: [PATCH] [PRISM] Match defined behavior for explicit block

Fixes [Bug #20748]
---
 prism_compile.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/prism_compile.c b/prism_compile.c
index b1f9b00bf6..9ea89d64e1 100644
--- a/prism_compile.c
+++ b/prism_compile.c
@@ -3889,6 +3889,12 @@ pm_compile_defined_expr0(rb_iseq_t *iseq, const pm_node_t *node, const pm_node_l
       }
       case PM_CALL_NODE: {
         const pm_call_node_t *cast = ((const pm_call_node_t *) node);
+
+        if (cast->block != NULL && PM_NODE_TYPE_P(cast->block, PM_BLOCK_NODE)) {
+            dtype = DEFINED_EXPR;
+            break;
+        }
+
         ID method_id = pm_constant_id_lookup(scope_node, cast->name);
 
         if (cast->receiver || cast->arguments) {