Intentions: Implement "Convert enum to sealed class" intention

#KT-14245 In Progress

idea/testData/intentions/convertEnumToSealedClass/.intention

@@ -0,0 +1 @@
+org.jetbrains.kotlin.idea.intentions.ConvertEnumToSealedClassIntention

idea/testData/intentions/convertEnumToSealedClass/entriesAndMembers.kt

@@ -0,0 +1,21 @@
+// WITH_RUNTIME
+
+enum class <caret>MyEnum(val s: String = "") {
+    FOO("FOO"), BAR("BAR"), DEFAULT();
+
+    fun foo() {
+
+    }
+}
+
+fun test(e: MyEnum) {
+    if (e == MyEnum.BAR) {
+        println()
+    }
+
+    val n = when (e) {
+        MyEnum.BAR -> 1
+        MyEnum.FOO -> 2
+        MyEnum.DEFAULT -> 0
+    }
+}

idea/testData/intentions/convertEnumToSealedClass/entriesAndMembers.kt.after

@@ -0,0 +1,24 @@
+// WITH_RUNTIME
+
+sealed class <caret>MyEnum(val s: String = "") {
+
+    fun foo() {
+
+    }
+
+    object FOO : MyEnum("FOO")
+    object BAR : MyEnum("BAR")
+    object DEFAULT : MyEnum()
+}
+
+fun test(e: MyEnum) {
+    if (e == MyEnum.BAR) {
+        println()
+    }
+
+    val n = when (e) {
+        MyEnum.BAR -> 1
+        MyEnum.FOO -> 2
+        MyEnum.DEFAULT -> 0
+    }
+}

idea/testData/intentions/convertEnumToSealedClass/entriesOnly.kt

@@ -0,0 +1,17 @@
+// WITH_RUNTIME
+
+enum class <caret>MyEnum(val s: String = "") {
+    FOO("FOO"), BAR("BAR"), DEFAULT()
+}
+
+fun test(e: MyEnum) {
+    if (e == MyEnum.BAR) {
+        println()
+    }
+
+    val n = when (e) {
+        MyEnum.BAR -> 1
+        MyEnum.FOO -> 2
+        MyEnum.DEFAULT -> 0
+    }
+}

idea/testData/intentions/convertEnumToSealedClass/entriesOnly.kt.after

@@ -0,0 +1,19 @@
+// WITH_RUNTIME
+
+sealed class <caret>MyEnum(val s: String = "") {
+    object FOO : MyEnum("FOO")
+    object BAR : MyEnum("BAR")
+    object DEFAULT : MyEnum()
+}
+
+fun test(e: MyEnum) {
+    if (e == MyEnum.BAR) {
+        println()
+    }
+
+    val n = when (e) {
+        MyEnum.BAR -> 1
+        MyEnum.FOO -> 2
+        MyEnum.DEFAULT -> 0
+    }
+}

idea/testData/intentions/convertEnumToSealedClass/membersOnly.kt

@@ -0,0 +1,9 @@
+// WITH_RUNTIME
+
+enum class <caret>MyEnum(val s: String = "") {
+    ;
+
+    fun foo() {
+
+    }
+}

idea/testData/intentions/convertEnumToSealedClass/membersOnly.kt.after

@@ -0,0 +1,7 @@
+// WITH_RUNTIME
+
+sealed class <caret>MyEnum(val s: String = "") {
+    fun foo() {
+
+    }
+}

idea/testData/intentions/convertEnumToSealedClass/notEnum.kt

@@ -0,0 +1,5 @@
+// IS_APPLICABLE: false
+
+class <caret>A {
+
+}

idea/testData/intentions/convertEnumToSealedClass/outOfRange.kt

@@ -0,0 +1,5 @@
+// IS_APPLICABLE: false
+
+<caret>internal enum class MyEnum {
+    A, B, C
+}