[Tests] Add regression test for #KT-66158

compiler/testData/diagnostics/tests/j+k/kjkRawTypeWithKotlinUpperBound.fir.kt

@@ -0,0 +1,16 @@
+// ISSUE: KT-66158
+// FILE: Java1.java
+public class Java1 extends KotlinClass { }
+
+// FILE: 1.kt
+open class KotlinClass<T : Number> {
+    open fun bar(): T? {
+        return null!!
+    }
+}
+
+class A : Java1()
+
+fun test(a: A) {
+    val k: Number = <!INITIALIZER_TYPE_MISMATCH, TYPE_MISMATCH!>a.bar()<!>
+}

compiler/testData/diagnostics/tests/j+k/kjkRawTypeWithKotlinUpperBound.kt

@@ -0,0 +1,16 @@
+// ISSUE: KT-66158
+// FILE: Java1.java
+public class Java1 extends KotlinClass { }
+
+// FILE: 1.kt
+open class KotlinClass<T : Number> {
+    open fun bar(): T? {
+        return null!!
+    }
+}
+
+class A : Java1()
+
+fun test(a: A) {
+    val k: Number = <!TYPE_MISMATCH!>a.bar()<!>
+}