Adding tests

tests/cases/conformance/types/typeRelationships/typeInference/unionTypeInference.ts

@@ -0,0 +1,20 @@
+// Verify that inferences made *to* a type parameter in a union type are secondary
+// to inferences made directly to that type parameter
+
+function f<T>(x: T, y: string|T): T {
+    return x;
+}
+function g<T>(value: [string, T]): T {
+    return value[1];
+}
+
+var a: number;
+var a = f(1, 2);
+var b: number;
+var b = f(1, "hello");
+var c: number;
+var c = f(1, a || "hello");
+var d: any;
+var d = f(undefined, "abc");
+var e: boolean;
+var e = g(["string", true]);