From d9bb8693410761b86948a99711cf1bf5ecbc73e4 Mon Sep 17 00:00:00 2001
From: Anders Hejlsberg <andersh@microsoft.com>
Date: Fri, 1 Mar 2019 16:34:23 -0800
Subject: [PATCH] Add regression test

---
 tests/cases/compiler/getParameterNameAtPosition.ts | 11 +++++++++++
 1 file changed, 11 insertions(+)
 create mode 100644 tests/cases/compiler/getParameterNameAtPosition.ts

diff --git a/tests/cases/compiler/getParameterNameAtPosition.ts b/tests/cases/compiler/getParameterNameAtPosition.ts
new file mode 100644
index 00000000000..e7a6dc40827
--- /dev/null
+++ b/tests/cases/compiler/getParameterNameAtPosition.ts
@@ -0,0 +1,11 @@
+// @strict: true
+
+// Repro from #30171
+
+interface Mock<Y extends any[]> extends Function {
+    (...args: Y): any;
+}
+type Tester = (opts: any, done: (...args: any[]) => any) => any;
+declare function cases(tester: Tester): void;
+declare function fn<Y extends any[]>(implementation?: (...args: Y) => any): Mock<Y>;
+cases(fn(opts => { }));