From 9fda7014cac88cd0885af42fccfb113ef289aadc Mon Sep 17 00:00:00 2001
From: Anders Hejlsberg <andersh@microsoft.com>
Date: Wed, 9 Jan 2019 16:16:24 -0800
Subject: [PATCH] Add regression tests

---
 .../conformance/types/conditional/conditionalTypes1.ts    | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/tests/cases/conformance/types/conditional/conditionalTypes1.ts b/tests/cases/conformance/types/conditional/conditionalTypes1.ts
index f5c67f678eb..2e8690a228b 100644
--- a/tests/cases/conformance/types/conditional/conditionalTypes1.ts
+++ b/tests/cases/conformance/types/conditional/conditionalTypes1.ts
@@ -353,3 +353,11 @@ declare function assign<T>(o: T, a: RecursivePartial<T>): void;
 
 var a = {o: 1, b: 2, c: [{a: 1, c: '213'}]}
 assign(a, {o: 2, c: {0: {a: 2, c: '213123'}}})
+
+// Repros from #23843
+
+type Weird1 = (<U extends boolean>(a: U) => never) extends 
+    (<U extends true>(a: U) => never) ? never : never;
+
+type Weird2 = (<U extends boolean>(a: U) => U) extends 
+    (<U extends true>(a: U) => infer T) ? T : never;