Added test.

tests/cases/compiler/unionTypeErrorMessageTypeRefs01.ts

@@ -0,0 +1,51 @@
+
+interface Foo { foo: any }
+interface Bar { bar: any }
+interface Baz { baz: any }
+interface Kwah { kwah: any }
+
+////////
+
+interface A<T> {
+    aProp: T;
+}
+
+interface B<T> {
+    bProp: T;
+}
+
+interface C<T> {
+    cProp: T;
+}
+
+declare const a: A<Foo>;
+declare const b: B<Foo>;
+declare const c: C<Foo>;
+declare let thingOfInterfaces: A<Bar> | B<Baz> | C<Kwah>;
+
+thingOfInterfaces = a;
+thingOfInterfaces = b;
+thingOfInterfaces = c;
+
+////////
+
+type X<T> = {
+    xProp: T;
+}
+
+type Y<T> = {
+    yProp: T;
+}
+
+type Z<T> = {
+    zProp: T;
+}
+
+declare const x: X<Foo>;
+declare const y: Y<Foo>;
+declare const z: Z<Foo>;
+declare let thingOfTypeAliases: X<Bar> | Y<Baz> | Z<Kwah>;
+
+thingOfTypeAliases = x;
+thingOfTypeAliases = y;
+thingOfTypeAliases = z;