[NI] Complex test for "not enough" information diagnostic

compiler/testData/diagnostics/tests/generics/kt30590.kt

@@ -0,0 +1,11 @@
+// !WITH_NEW_INFERENCE
+// !DIAGNOSTICS: -UNUSED_PARAMETER -UNUSED_VARIABLE
+// !LANGUAGE: +NewInference
+// Issue: KT-30590
+
+interface A
+fun <T: A, R: T> emptyStrangeMap(): Map<T, R> = TODO()
+fun test7() : Map<A, A> = emptyStrangeMap()
+
+fun test() = emptyStrangeMap()
+

compiler/testData/diagnostics/tests/generics/kt30590.txt

@@ -0,0 +1,10 @@
+package
+
+public fun </*0*/ T : A, /*1*/ R : T> emptyStrangeMap(): kotlin.collections.Map<T, R>
+public fun test7(): kotlin.collections.Map<A, A>
+
+public interface A {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}