[FIR] Adding a test case to show resolution of KT-29559 in K2

compiler/testData/diagnostics/tests/smartCasts/incrementAfterAssignment.kt

@@ -0,0 +1,27 @@
+// WITH_STDLIB
+// SKIP_TEXT
+// ISSUE: KT-29559
+
+fun consume(i: Int) {}
+fun consume(c: Char) {}
+fun consume(a: Any?) {}
+
+fun test1() {
+    var a: Any
+
+    a = 1
+    consume(<!DEBUG_INFO_SMARTCAST!>a<!>)
+
+    a = 1
+    consume(<!TYPE_MISMATCH!><!DEBUG_INFO_SMARTCAST!>a<!>++<!>)
+
+    a = 1
+    consume(++<!DEBUG_INFO_SMARTCAST!>a<!>)
+
+    a = 't'
+    consume(<!TYPE_MISMATCH!><!DEBUG_INFO_SMARTCAST!>a<!>++<!>)
+
+    a = 't'
+    consume(++<!DEBUG_INFO_SMARTCAST!>a<!>)
+    consume(<!DEBUG_INFO_SMARTCAST!><!DEBUG_INFO_SMARTCAST!>a<!>++<!>)
+}