[Tests] Migrate backend-independent tests from native to compiler/testData.

^KT-65979

compiler/testData/codegen/box/enum/switchLowering.kt

@@ -0,0 +1,105 @@
+/*
+ * Copyright 2010-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
+ * that can be found in the LICENSE file.
+ */
+// JVM_ABI_K1_K2_DIFF: KT-63864
+// !LANGUAGE:-ProhibitComparisonOfIncompatibleEnums
+// WITH_STDLIB
+
+import kotlin.test.*
+
+val sb = StringBuilder()
+
+enum class EnumA {
+    A, B, C
+}
+
+enum class EnumB {
+    A, B
+}
+
+enum class E {
+    ONE, TWO, THREE
+}
+
+fun produceEntry() = EnumA.A
+
+// Check that we fail on comparison of different enum types.
+fun differentEnums() {
+    sb.appendLine(when (produceEntry()) {
+        EnumB.A -> "EnumB.A"
+        EnumA.A -> "EnumA.A"
+        EnumA.B -> "EnumA.B"
+        else    -> "nah"
+    })
+}
+
+// Nullable subject shouldn't be lowered.
+fun nullable() {
+    val x: EnumA? = null
+    when(x) {
+        EnumA.A -> sb.appendLine("fail")
+        else    -> sb.appendLine("ok")
+    }
+}
+
+// Operator overloading won't trick us!
+fun operatorOverloading() {
+    operator fun E.contains(other: E): Boolean = false
+
+    val y = E.ONE
+    when(y) {
+        in E.ONE    -> sb.appendLine("Should not reach here")
+        else        -> sb.appendLine("ok")
+    }
+}
+
+fun smoke1() {
+    when (produceEntry()) {
+        EnumA.B -> sb.appendLine("error")
+        EnumA.A -> sb.appendLine("ok")
+        EnumA.C -> sb.appendLine("error")
+    }
+}
+
+fun smoke2() {
+    when (produceEntry()) {
+        EnumA.B -> sb.appendLine("error")
+        else    -> sb.appendLine("ok")
+    }
+}
+
+fun eA() = EnumA.A
+
+fun eB() = EnumA.B
+
+
+fun nestedWhen() {
+    sb.appendLine(when (eA()) {
+        EnumA.A, EnumA.C -> when (eB()) {
+            EnumA.B -> "ok"
+            else -> "nope"
+        }
+        else -> "nope"
+    })
+}
+
+fun box(): String {
+    differentEnums()
+    nullable()
+    operatorOverloading()
+    smoke1()
+    smoke2()
+    nestedWhen()
+
+    assertEquals("""
+        EnumA.A
+        ok
+        ok
+        ok
+        ok
+        ok
+
+    """.trimIndent(), sb.toString())
+    return "OK"
+}