[NI] Discriminate constraints with Nothing(?) lower bounds

compiler/testData/diagnostics/tests/inference/nothingType/complexDependancyOnVariableWithTrivialConstraint.kt

@@ -0,0 +1,15 @@
+// !LANGUAGE: +NewInference
+// !DIAGNOSTICS: -UNUSED_PARAMETER
+
+// Validation test.
+// Check that type variable is fixed to Data<Nothing> as it's used in input types for lambda
+
+class Data<T>(val x: T) {
+    fun dataMethod() {}
+}
+
+fun <K> bar(x: K, y: (K) -> Unit) {}
+
+fun test() {
+    bar(Data(null)) { it.dataMethod() }
+}

compiler/testData/diagnostics/tests/inference/nothingType/complexDependancyOnVariableWithTrivialConstraint.txt

@@ -0,0 +1,13 @@
+package
+
+public fun </*0*/ K> bar(/*0*/ x: K, /*1*/ y: (K) -> kotlin.Unit): kotlin.Unit
+public fun test(): kotlin.Unit
+
+public final class Data</*0*/ T> {
+    public constructor Data</*0*/ T>(/*0*/ x: T)
+    public final val x: T
+    public final fun dataMethod(): kotlin.Unit
+    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
+}

compiler/testData/diagnostics/tests/inference/nothingType/nothingWithCallableReference.kt

@@ -0,0 +1,33 @@
+// !LANGUAGE: +NewInference
+// !DIAGNOSTICS: -UNUSED_PARAMETER
+
+fun <K> select2(x: K, y: K): K = TODO()
+fun <K> select3(x: K, y: K, z: K): K = TODO()
+
+fun <K : S, S> dependantSelect2(x: K, y: S) {}
+fun <K : S, S> dependantSelect3(x: K, y: K, z: S) {}
+
+fun foo() {}
+fun cloneFoo() {}
+fun bar(x: Int) {}
+
+fun test(f1: (Int) -> Unit, f2: kotlin.Function1<Int, Unit>) {
+    select2(null, ::foo)
+    select3(null, f1, ::bar)
+    select3(null, f2, ::bar)
+
+    select3(null, f1, <!TYPE_MISMATCH!>::foo<!>)
+    select3(null, f2, <!TYPE_MISMATCH!>::foo<!>)
+
+    dependantSelect2(null, ::foo)
+    dependantSelect3(null, ::foo, ::cloneFoo)
+    dependantSelect3(null, f1, ::bar)
+    // Here we have LOWER(Nothing?), UPPER(Function1) and therefore type variable is fixed to the former
+    dependantSelect3(null, <!TYPE_MISMATCH!>::bar<!>, f1)
+
+    // These errors are actually can be fixed (and, probably, should) if we force resolution of callable reference
+    dependantSelect3(null, ::foo, <!TYPE_MISMATCH!>::bar<!>)
+    dependantSelect3(null, ::bar, <!TYPE_MISMATCH!>::foo<!>)
+    dependantSelect3(null, f1, <!TYPE_MISMATCH!>::foo<!>)
+    dependantSelect3(null, <!TYPE_MISMATCH!>::foo<!>, f1)
+}

compiler/testData/diagnostics/tests/inference/nothingType/nothingWithCallableReference.txt

@@ -0,0 +1,10 @@
+package
+
+public fun bar(/*0*/ x: kotlin.Int): kotlin.Unit
+public fun cloneFoo(): kotlin.Unit
+public fun </*0*/ K : S, /*1*/ S> dependantSelect2(/*0*/ x: K, /*1*/ y: S): kotlin.Unit
+public fun </*0*/ K : S, /*1*/ S> dependantSelect3(/*0*/ x: K, /*1*/ y: K, /*2*/ z: S): kotlin.Unit
+public fun foo(): kotlin.Unit
+public fun </*0*/ K> select2(/*0*/ x: K, /*1*/ y: K): K
+public fun </*0*/ K> select3(/*0*/ x: K, /*1*/ y: K, /*2*/ z: K): K
+public fun test(/*0*/ f1: (kotlin.Int) -> kotlin.Unit, /*1*/ f2: (kotlin.Int) -> kotlin.Unit): kotlin.Unit