NI: take into account an extension function annotation during CST calculation

compiler/testData/diagnostics/tests/inference/kt36819.fir.kt

@@ -0,0 +1,47 @@
+// !LANGUAGE: +NewInference
+// !DIAGNOSTICS: -UNUSED_PARAMETER -UNUSED_VARIABLE -UNUSED_ANONYMOUS_PARAMETER -CAST_NEVER_SUCCEEDS
+// ISSUE: KT-36819
+
+// Case 1
+
+fun <K> select(vararg x: K) = x[0]
+interface A
+class B: A
+class C: A
+fun <T> id1(x: T): T = x
+fun <R> id2(x: R): R = x
+
+class Out<out R>(x: R)
+
+fun main() {
+    val x1 = select(id1 { B() }, id2 { C() })
+    val x2 = select({ B() }, { C() })
+    val x3 = select(id1(Out(B())), id2(Out(C())))
+}
+
+// Case 2
+
+fun <R> fold(initial: R, operation: (R) -> Unit) {}
+
+fun foo() {
+    fold({ x: Int -> x }) { acc -> }
+}
+
+// Case 3
+
+class Foo
+
+typealias X = Foo.(Foo.() -> Unit) -> Unit
+
+fun bar() {
+    val y = when {
+        false -> { _ ->
+            Unit
+        }
+        true -> null as X
+        else -> { x ->
+            <!UNRESOLVED_REFERENCE!>x<!>()
+            Unit
+        }
+    }
+}

compiler/testData/diagnostics/tests/inference/kt36819.kt

@@ -1,8 +1,9 @@
-// FIR_IDENTICAL
 // !LANGUAGE: +NewInference
-// !DIAGNOSTICS: -UNUSED_PARAMETER -UNUSED_VARIABLE -UNUSED_ANONYMOUS_PARAMETER
+// !DIAGNOSTICS: -UNUSED_PARAMETER -UNUSED_VARIABLE -UNUSED_ANONYMOUS_PARAMETER -CAST_NEVER_SUCCEEDS
 // ISSUE: KT-36819
 
+// Case 1
+
 fun <K> select(vararg x: K) = x[0]
 interface A
 class B: A
@@ -18,8 +19,29 @@ fun main() {
     val x3 = select(id1(Out(B())), id2(Out(C())))
 }
 
+// Case 2
+
 fun <R> fold(initial: R, operation: (R) -> Unit) {}
 
 fun foo() {
     fold({ x: Int -> x }) { acc -> }
 }
+
+// Case 3
+
+class Foo
+
+typealias X = Foo.(Foo.() -> Unit) -> Unit
+
+fun bar() {
+    val y = when {
+        false -> { _ ->
+            Unit
+        }
+        true -> null as X
+        else -> { x ->
+            x()
+            Unit
+        }
+    }
+}

compiler/testData/diagnostics/tests/inference/kt36819.txt

@@ -1,5 +1,6 @@
 package
 
+public fun bar(): kotlin.Unit
 public fun </*0*/ R> fold(/*0*/ initial: R, /*1*/ operation: (R) -> kotlin.Unit): kotlin.Unit
 public fun foo(): kotlin.Unit
 public fun </*0*/ T> id1(/*0*/ x: T): T
@@ -27,9 +28,17 @@ public final class C : A {
     public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }
 
+public final class Foo {
+    public constructor Foo()
+    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
+}
+
 public final class Out</*0*/ out R> {
     public constructor Out</*0*/ out R>(/*0*/ x: R)
     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
 }
+public typealias X = Foo.(Foo.() -> kotlin.Unit) -> kotlin.Unit