From 13bf022ef67cb0f5a6a73d2a9a3aa2867305c7f7 Mon Sep 17 00:00:00 2001
From: Anders Hejlsberg <andersh@microsoft.com>
Date: Thu, 11 Jan 2018 16:45:44 -0800
Subject: [PATCH] Add regression tests

---
 tests/cases/compiler/strictFunctionTypes1.ts | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/tests/cases/compiler/strictFunctionTypes1.ts b/tests/cases/compiler/strictFunctionTypes1.ts
index 6c07bc51ffe..ad8836fcf05 100644
--- a/tests/cases/compiler/strictFunctionTypes1.ts
+++ b/tests/cases/compiler/strictFunctionTypes1.ts
@@ -17,3 +17,13 @@ const x1 = f1(fo, fs);  // (x: string) => void
 const x2 = f2("abc", fo, fs);  // "abc"
 const x3 = f3("abc", fo, fx);  // "abc" | "def"
 const x4 = f4(fo, fs);  // Func<string>
+
+declare const never: never;
+
+const x10 = f2(never, fo, fs);  // string
+const x11 = f3(never, fo, fx);  // "def"
+
+// Repro from #21112
+
+declare function foo<T>(a: ReadonlyArray<T>): T;
+let x = foo([]);  // never