[FIR-TEST] Add new testdata generated after changes in previous commit

compiler/testData/diagnostics/tests/smartCasts/objectLiterals/assignment.fir.kt

@@ -0,0 +1,19 @@
+// See KT-6293: Smart cast doesn't work after object literal
+abstract class Runnable {
+    abstract fun run()
+}
+
+fun foo(): Int {
+    val c: Int? = null
+    if (c is Int) {
+        var k: Runnable
+        val d: Int = c
+        k = object: Runnable() {
+            override fun run() = Unit
+        }
+        // Unnecessary but not important smart cast
+        k.run()
+        return c + d
+    }
+    else return -1
+}