Tests for checking if type S is subtype of union type

T is a union type and S is a subtype of at least one constituent type of T

tests/cases/conformance/types/typeRelationships/subtypesAndSuperTypes/subtypesOfUnion.ts

@@ -0,0 +1,52 @@
+enum E { e1, e2 }
+interface I8 { [x: string]: number[]; }
+class A { foo: number; }
+class A2<T> { foo: T; }
+function f() { }
+module f { export var bar = 1; }
+class c { baz: string }
+module c { export var bar = 1; }
+
+// A type T is a subtype of a union type U if T is a subtype of any type in U.
+interface I1<T> {
+    [x: string]: string | number;
+    foo: any; // ok
+    foo2: string; // ok
+    foo3: number; // ok
+    foo4: boolean; // error 
+    foo5: E; // ok - subtype of number 
+    foo6: Date; // error
+    foo7: RegExp; // error
+    foo8: { bar: number }; // error
+    foo9: I8; // error
+    foo10: A; // error
+    foo11: A2<number>; // error
+    foo12: (x) => number; //error
+    foo13: <T>(x: T) => T; // error
+    foo14: typeof f; // error
+    foo15: typeof c; // error
+    foo16: T; // error
+    foo17: Object; // error
+    foo18: {}; // error
+}
+interface I2<T> {
+    [x: string]: E | number;
+    foo: any; // ok
+    foo2: string; // error
+    foo3: number; // ok
+    foo4: boolean; // error 
+    foo5: E; // ok
+    foo6: Date; // error
+    foo7: RegExp; // error
+    foo8: { bar: number }; // error
+    foo9: I8; // error
+    foo10: A; // error
+    foo11: A2<number>; // error
+    foo12: (x) => number; //error
+    foo13: <T>(x: T) => T; // error
+    foo14: typeof f; // error
+    foo15: typeof c; // error
+    foo16: T; // error
+    foo17: Object; // error
+    foo18: {}; // error
+}