Support local property delegation to inline class values

Also, add extra test on property delegation.

compiler/testData/codegen/box/inlineClasses/propertyDelegation/captureLocalVarDelegatedToInlineClass.kt

@@ -0,0 +1,91 @@
+// !LANGUAGE: +InlineClasses
+// IGNORE_BACKEND: JVM_IR
+
+var setterInvoked = 0
+
+var backing = 42
+
+inline class DelegateStr(val ignored: String) {
+
+    operator fun getValue(thisRef: Any?, prop: Any?) =
+        backing
+
+    operator fun setValue(thisRef: Any?, prop: Any?, newValue: Int) {
+        setterInvoked++
+        backing = newValue
+    }
+}
+
+inline class DelegateInt(val ignored: Int) {
+
+    operator fun getValue(thisRef: Any?, prop: Any?) =
+        backing
+
+    operator fun setValue(thisRef: Any?, prop: Any?, newValue: Int) {
+        setterInvoked++
+        backing = newValue
+    }
+}
+
+inline class DelegateLong(val ignored: Long) {
+
+    operator fun getValue(thisRef: Any?, prop: Any?) =
+        backing
+
+    operator fun setValue(thisRef: Any?, prop: Any?, newValue: Int) {
+        setterInvoked++
+        backing = newValue
+    }
+}
+
+fun box(): String {
+    setterInvoked = 0
+    testDelegateStr()
+    if (setterInvoked != 1) throw AssertionError()
+
+    setterInvoked = 0
+    testDelegateInt()
+    if (setterInvoked != 1) throw AssertionError()
+
+    setterInvoked = 0
+    testDelegateLong()
+    if (setterInvoked != 1) throw AssertionError()
+
+    return "OK"
+}
+
+private fun testDelegateStr() {
+    var localD by DelegateStr("don't care")
+
+    return {
+        if (localD != 42) AssertionError()
+
+        localD = 1234
+        if (localD != 1234) throw AssertionError()
+        if (backing != 1234) throw AssertionError()
+    }()
+}
+
+private fun testDelegateInt() {
+    var localD by DelegateInt(999)
+
+    return {
+        if (localD != 42) AssertionError()
+
+        localD = 1234
+        if (localD != 1234) throw AssertionError()
+        if (backing != 1234) throw AssertionError()
+    }()
+}
+
+private fun testDelegateLong() {
+    var localD by DelegateLong(999L)
+
+    return {
+        if (localD != 42) AssertionError()
+
+        localD = 1234
+        if (localD != 1234) throw AssertionError()
+        if (backing != 1234) throw AssertionError()
+    }()
+}

compiler/testData/codegen/box/inlineClasses/propertyDelegation/delegateLocalVarToInlineClass.kt

@@ -0,0 +1,85 @@
+// !LANGUAGE: +InlineClasses
+// IGNORE_BACKEND: JVM_IR
+
+var setterInvoked = 0
+
+var backing = 42
+
+inline class DelegateStr(val ignored: String) {
+
+    operator fun getValue(thisRef: Any?, prop: Any?) =
+        backing
+
+    operator fun setValue(thisRef: Any?, prop: Any?, newValue: Int) {
+        setterInvoked++
+        backing = newValue
+    }
+}
+
+inline class DelegateInt(val ignored: Int) {
+
+    operator fun getValue(thisRef: Any?, prop: Any?) =
+        backing
+
+    operator fun setValue(thisRef: Any?, prop: Any?, newValue: Int) {
+        setterInvoked++
+        backing = newValue
+    }
+}
+
+inline class DelegateLong(val ignored: Long) {
+
+    operator fun getValue(thisRef: Any?, prop: Any?) =
+        backing
+
+    operator fun setValue(thisRef: Any?, prop: Any?, newValue: Int) {
+        setterInvoked++
+        backing = newValue
+    }
+}
+
+fun box(): String {
+    setterInvoked = 0
+    testDelegateStr()
+    if (setterInvoked != 1) throw AssertionError()
+
+    setterInvoked = 0
+    testDelegateInt()
+    if (setterInvoked != 1) throw AssertionError()
+
+    setterInvoked = 0
+    testDelegateLong()
+    if (setterInvoked != 1) throw AssertionError()
+
+    return "OK"
+}
+
+private fun testDelegateStr() {
+    var localD by DelegateStr("don't care")
+
+    if (localD != 42) AssertionError()
+
+    localD = 1234
+    if (localD != 1234) throw AssertionError()
+    if (backing != 1234) throw AssertionError()
+}
+
+private fun testDelegateInt() {
+    var localD by DelegateInt(999)
+
+    if (localD != 42) AssertionError()
+
+    localD = 1234
+    if (localD != 1234) throw AssertionError()
+    if (backing != 1234) throw AssertionError()
+}
+
+private fun testDelegateLong() {
+    var localD by DelegateLong(999L)
+
+    if (localD != 42) AssertionError()
+
+    localD = 1234
+    if (localD != 1234) throw AssertionError()
+    if (backing != 1234) throw AssertionError()
+}

compiler/testData/codegen/box/inlineClasses/propertyDelegation/delegatePrivateCompanionVarToInlineClass.kt

@@ -0,0 +1,37 @@
+// !LANGUAGE: +InlineClasses
+// IGNORE_BACKEND: JVM_IR
+
+class Foo {
+    companion object {
+        var a: Int = 42
+        private var d by Delegate(0)
+
+        fun d() = d
+        fun d(newValue: Int) { d = newValue }
+    }
+}
+
+var setterInvoked = 0
+
+inline class Delegate(val ignored: Int) {
+
+    operator fun getValue(thisRef: Any?, prop: Any?) = Foo.a
+
+    operator fun setValue(thisRef: Any?, prop: Any?, newValue: Int) {
+        setterInvoked++
+        Foo.a = newValue
+    }
+}
+
+
+fun box(): String {
+    if (Foo.d() != 42) throw AssertionError()
+
+    Foo.d(1234)
+    if (Foo.d() != 1234) throw AssertionError()
+    if (Foo.a != 1234) throw AssertionError()
+
+    if (setterInvoked != 1) throw AssertionError()
+
+    return "OK"
+}