Make RubyVM::AbstractSyntaxTree.of raise for method/proc created in eval

This changes Thread::Location::Backtrace#absolute_path to return
nil for methods/procs defined in eval.  If the realpath of an iseq
is nil, that indicates it was defined in eval, in which case you
cannot use RubyVM::AbstractSyntaxTree.of.

Fixes [Bug #16983]

Co-authored-by: Koichi Sasada <ko1@atdot.net>

1 files changed, 3 insertions, 0 deletions

diff --git a/ast.c b/ast.c
index 32d8ab9eb6..20c4588cd7 100644
--- a/ast.c
+++ b/ast.c
@@ -213,6 +213,9 @@ ast_s_of(rb_execution_context_t *ec, VALUE module, VALUE body, VALUE save_script
         else {
             iseq = rb_method_iseq(body);
         }
+        if (rb_iseq_from_eval_p(iseq)) {
+            rb_raise(rb_eArgError, "cannot get AST for method defined in eval");
+        }
         path = rb_iseq_path(iseq);
         node_id = iseq->body->location.node_id;
     }