From c2b0d7ea1c9becee5e4af5147398127d5fef9a29 Mon Sep 17 00:00:00 2001
From: Yusuke Endoh <mame@ruby-lang.org>
Date: Fri, 9 Aug 2024 17:12:52 +0900
Subject: [PATCH] Tentatively accept anything as a proc type

---
 lib/typeprof/core/ast/sig_type.rb |  2 +-
 scenario/misc/proc.rb             | 15 +++++++++++++++
 2 files changed, 16 insertions(+), 1 deletion(-)
 create mode 100644 scenario/misc/proc.rb

diff --git a/lib/typeprof/core/ast/sig_type.rb b/lib/typeprof/core/ast/sig_type.rb
index bd4cbaa5..72bcde86 100644
--- a/lib/typeprof/core/ast/sig_type.rb
+++ b/lib/typeprof/core/ast/sig_type.rb
@@ -590,7 +590,7 @@ def covariant_vertex0(genv, changes, vtx, subst)
       end
 
       def contravariant_vertex0(genv, changes, vtx, subst)
-        raise NotImplementedError
+        Source.new()
       end
 
       def show
diff --git a/scenario/misc/proc.rb b/scenario/misc/proc.rb
new file mode 100644
index 00000000..85172351
--- /dev/null
+++ b/scenario/misc/proc.rb
@@ -0,0 +1,15 @@
+## update: test.rbs
+class Object
+  def foo: (^(Integer) -> void) -> void
+end
+
+## update: test.rb
+def check(x)
+end
+f = ->(x) { check(x) } # TODO: this should pass an Integer to the method "check"? Is it possible?
+foo(f)
+
+## assert
+class Object
+  def check: (untyped) -> nil
+end