FIR checkers: report SMARTCAST_IMPOSSIBLE

compiler/testData/diagnostics/tests/smartCasts/inference/kt39010.fir.kt

@@ -1,11 +0,0 @@
-class A<E> {
-    fun foo(): E = TODO()
-}
-
-class B(var a: A<*>?) {
-    fun bar() {
-        if (a != null) {
-            a<!UNSAFE_CALL!>.<!>foo()
-        }
-    }
-}

compiler/testData/diagnostics/tests/smartCasts/inference/kt39010.kt

@@ -1,3 +1,4 @@
+// FIR_IDENTICAL
 class A<E> {
     fun foo(): E = TODO()
 }

compiler/testData/diagnostics/tests/smartCasts/inference/kt39010_2.fir.kt

@@ -1,16 +0,0 @@
-open class A<E> {
-}
-
-class B : A<String>() {
-    fun foo() {}
-}
-
-interface KI {
-    val a: A<*>
-}
-
-fun KI.bar() {
-    if (a is B) {
-        a.<!UNRESOLVED_REFERENCE!>foo<!>()
-    }
-}

compiler/testData/diagnostics/tests/smartCasts/inference/kt39010_2.kt

@@ -1,3 +1,4 @@
+// FIR_IDENTICAL
 open class A<E> {
 }
 

compiler/testData/diagnostics/tests/smartCasts/inference/unneededUnstableSmartcast.kt

@@ -0,0 +1,8 @@
+// FIR_IDENTICAL
+class Test<E>(var c: Collection<E>) {
+    fun test() {
+        if (c is List<*>) {
+            c.size // smartcast is unstable, but `size` is also available from `Collection`, so there should not be any error
+        }
+    }
+}