From 07e4819b8bb5db64c2d00c91b7ce184de1eb4723 Mon Sep 17 00:00:00 2001
From: Anders Hejlsberg <andersh@microsoft.com>
Date: Wed, 11 Oct 2017 12:01:38 -0700
Subject: [PATCH] Add regression test

---
 tests/cases/compiler/mutuallyRecursiveCallbacks.ts | 7 +++++++
 1 file changed, 7 insertions(+)
 create mode 100644 tests/cases/compiler/mutuallyRecursiveCallbacks.ts

diff --git a/tests/cases/compiler/mutuallyRecursiveCallbacks.ts b/tests/cases/compiler/mutuallyRecursiveCallbacks.ts
new file mode 100644
index 00000000000..94f2d285786
--- /dev/null
+++ b/tests/cases/compiler/mutuallyRecursiveCallbacks.ts
@@ -0,0 +1,7 @@
+// Repro from #18277
+
+interface Foo<T> { (bar: Bar<T>): void };
+type Bar<T> = (foo: Foo<T>) => Foo<T>;
+declare function foo<T>(bar: Bar<T>): void;
+declare var bar: Bar<{}>;
+bar = foo;