Add regression test

ahejlsberg · ahejlsberg · commit 7d11c7fe40b4 · 2016-05-21T11:17:47.000-07:00
diff --git a/tests/cases/compiler/subtypeRelationForNever.ts b/tests/cases/compiler/subtypeRelationForNever.ts
@@ -0,0 +1,6 @@
+function fail(message: string) : never { throw new Error(message); }
+function withFew<a, r>(values: a[], haveFew: (values: a[]) => r, haveNone: (reason: string) => r): r {
+    return values.length > 0 ? haveFew(values) : haveNone('No values.');
+}
+function id<a>(value: a) : a { return value; }
+const result = withFew([1, 2, 3], id, fail); // expected result is number[]
