Nullable function-like property call is prohibited now #KT-8252 Fixed

compiler/testData/diagnostics/tests/SafeCallInvoke.kt

@@ -0,0 +1,23 @@
+class Rule(val apply:() -> Unit)
+
+fun bar() {}
+
+fun foo() {
+    val rule: Rule? = Rule { bar() }
+
+    // this compiles and works
+    val apply = rule?.apply
+    if (apply != null) <!DEBUG_INFO_SMARTCAST!>apply<!>()
+
+    // this compiles and works
+    rule?.apply?.invoke()
+
+    // this should be an error
+    rule?.<!UNSAFE_CALL!>apply<!>()
+
+    // these both also ok (with smart cast / unnecessary safe call)
+    if (rule != null) {
+        <!DEBUG_INFO_SMARTCAST!>rule<!>.apply()
+        rule<!UNNECESSARY_SAFE_CALL!>?.<!>apply()
+    }
+}