Rename SuccessOrFailure to Result and hide Failure from ABI

* The members of Result are isSuccess, isFailure, exceptionOrNull, getOrNull
* The rest of API is implemented via inline-only extensions
* There are two internal functions to hide detailed mechanics of an internal
  Result.Failure class: createFailure and throwOnFailure
* Result.toString is explicit: either Success(v) or Failure(x)

See KT-26538

compiler/testData/codegen/box/coroutines/debug/debuggerMetadata.kt

@@ -99,7 +99,7 @@ fun box(): String {
     if (res != "first") {
         return "" + res
     }
-    continuation!!.resumeWith(SuccessOrFailure.success(Unit))
+    continuation!!.resumeWith(Result.success(Unit))
     res = (continuation!! as BaseContinuationImpl).getSpilledVariableFieldMapping()!!.toMap()["I$0"] ?: "multipleLocalsInOneSlot fail 2"
     if (res != "second") {
         return "" + res

compiler/testData/codegen/box/coroutines/inlineClasses/bridgeGenerationCrossinline.kt

@@ -10,30 +10,30 @@ fun builder(c: suspend () -> Unit) {
 }
 
 @Suppress("UNSUPPORTED_FEATURE")
-inline class SuccessOrFailure<T>(val a: Any?) {
+inline class Result<T>(val a: Any?) {
     fun getOrThrow(): T = a as T
 }
 
-abstract class SuccessOrFailureReceiver<T> {
-    abstract suspend fun receive(result: SuccessOrFailure<T>)
+abstract class ResultReceiver<T> {
+    abstract suspend fun receive(result: Result<T>)
 }
 
-inline fun <T> SuccessOrFailureReceiver(crossinline f: (SuccessOrFailure<T>) -> Unit): SuccessOrFailureReceiver<T> =
-    object : SuccessOrFailureReceiver<T>() {
-        override suspend fun receive(result: SuccessOrFailure<T>) {
+inline fun <T> ResultReceiver(crossinline f: (Result<T>) -> Unit): ResultReceiver<T> =
+    object : ResultReceiver<T>() {
+        override suspend fun receive(result: Result<T>) {
             f(result)
         }
     }
 
 fun test() {
     var invoked = false
-    val receiver = SuccessOrFailureReceiver<String> { result ->
+    val receiver = ResultReceiver<String> { result ->
         val intResult = result.getOrThrow()
         invoked = true
     }
 
     builder  {
-        receiver.receive(SuccessOrFailure("42"))
+        receiver.receive(Result("42"))
     }
     if (!invoked) {
         throw RuntimeException("Fail")

compiler/testData/codegen/box/coroutines/inlineClasses/bridgeGenerationNonInline.kt

@@ -10,30 +10,30 @@ fun builder(c: suspend () -> Unit) {
 }
 
 @Suppress("UNSUPPORTED_FEATURE")
-inline class SuccessOrFailure<T>(val a: Any?) {
+inline class Result<T>(val a: Any?) {
     fun getOrThrow(): T = a as T
 }
 
-abstract class SuccessOrFailureReceiver<T> {
-    abstract suspend fun receive(result: SuccessOrFailure<T>)
+abstract class ResultReceiver<T> {
+    abstract suspend fun receive(result: Result<T>)
 }
 
-fun <T> SuccessOrFailureReceiver(f: (SuccessOrFailure<T>) -> Unit): SuccessOrFailureReceiver<T> =
-    object : SuccessOrFailureReceiver<T>() {
-        override suspend fun receive(result: SuccessOrFailure<T>) {
+fun <T> ResultReceiver(f: (Result<T>) -> Unit): ResultReceiver<T> =
+    object : ResultReceiver<T>() {
+        override suspend fun receive(result: Result<T>) {
             f(result)
         }
     }
 
 fun test() {
     var invoked = false
-    val receiver = SuccessOrFailureReceiver<Int> { result ->
+    val receiver = ResultReceiver<Int> { result ->
         val intResult = result.getOrThrow()
         invoked = true
     }
 
     builder {
-        receiver.receive(SuccessOrFailure(42))
+        receiver.receive(Result(42))
     }
     if (!invoked) {
         throw RuntimeException("Fail")

compiler/testData/codegen/box/coroutines/reflect/callSuspend.kt

@@ -30,7 +30,7 @@ var proceed = {}
 
 suspend fun suspendHere() = suspendCoroutineUninterceptedOrReturn<Unit> { cont ->
     proceed = {
-        cont.resumeWith(SuccessOrFailure.success(Unit))
+        cont.resumeWith(Result.success(Unit))
     }
     COROUTINE_SUSPENDED
 }

compiler/testData/codegen/box/coroutines/reflect/callSuspendBy.kt

@@ -32,7 +32,7 @@ var proceed = {}
 
 suspend fun suspendHere() = suspendCoroutineUninterceptedOrReturn<Unit> { cont ->
     proceed = {
-        cont.resumeWith(SuccessOrFailure.success(Unit))
+        cont.resumeWith(Result.success(Unit))
     }
     COROUTINE_SUSPENDED
 }

compiler/testData/codegen/box/inlineClasses/bridgeGenerationWithInlineClassOverAny.kt

@@ -1,29 +1,29 @@
 // !LANGUAGE: +InlineClasses
 // IGNORE_BACKEND: JVM_IR
 
-inline class SuccessOrFailure<T>(val a: Any?) {
+inline class Result<T>(val a: Any?) {
     fun getOrThrow(): T = a as T
 }
 
-abstract class SuccessOrFailureReceiver<T> {
-    abstract fun receive(result: SuccessOrFailure<T>)
+abstract class ResultReceiver<T> {
+    abstract fun receive(result: Result<T>)
 }
 
-fun <T> SuccessOrFailureReceiver(f: (SuccessOrFailure<T>) -> Unit): SuccessOrFailureReceiver<T> =
-    object : SuccessOrFailureReceiver<T>() {
-        override fun receive(result: SuccessOrFailure<T>) {
+fun <T> ResultReceiver(f: (Result<T>) -> Unit): ResultReceiver<T> =
+    object : ResultReceiver<T>() {
+        override fun receive(result: Result<T>) {
             f(result)
         }
     }
 
 fun test() {
     var invoked = false
-    val receiver = SuccessOrFailureReceiver<Int> { result ->
+    val receiver = ResultReceiver<Int> { result ->
         val intResult = result.getOrThrow()
         invoked = true
     }
 
-    receiver.receive(SuccessOrFailure(42))
+    receiver.receive(Result(42))
     if (!invoked) {
         throw RuntimeException("Fail")
     }

compiler/testData/codegen/box/inlineClasses/crossinlineWithInlineClassInParameter.kt

@@ -1,29 +1,29 @@
 // !LANGUAGE: +InlineClasses
 // IGNORE_BACKEND: JVM_IR
 
-inline class SuccessOrFailure<T>(val a: Any?) {
+inline class Result<T>(val a: Any?) {
     fun getOrThrow(): T = a as T
 }
 
-abstract class SuccessOrFailureReceiver<T> {
-    abstract fun receive(result: SuccessOrFailure<T>)
+abstract class ResultReceiver<T> {
+    abstract fun receive(result: Result<T>)
 }
 
-inline fun <T> SuccessOrFailureReceiver(crossinline f: (SuccessOrFailure<T>) -> Unit): SuccessOrFailureReceiver<T> =
-    object : SuccessOrFailureReceiver<T>() {
-        override fun receive(result: SuccessOrFailure<T>) {
+inline fun <T> ResultReceiver(crossinline f: (Result<T>) -> Unit): ResultReceiver<T> =
+    object : ResultReceiver<T>() {
+        override fun receive(result: Result<T>) {
             f(result)
         }
     }
 
 fun test() {
     var invoked = false
-    val receiver = SuccessOrFailureReceiver<String> { result ->
+    val receiver = ResultReceiver<String> { result ->
         val intResult = result.getOrThrow()
         invoked = true
     }
 
-    receiver.receive(SuccessOrFailure("42"))
+    receiver.receive(Result("42"))
     if (!invoked) {
         throw RuntimeException("Fail")
     }

compiler/testData/codegen/box/inlineClasses/kt25771.kt

@@ -1,15 +1,15 @@
 // !LANGUAGE: +InlineClasses
 // IGNORE_BACKEND: JVM_IR
 
-inline class SuccessOrFailure<out T>(val value: Any?) {
+inline class Result<out T>(val value: Any?) {
     val isFailure: Boolean get() = value is Failure
 
     public companion object {
-        public inline fun <T> success(value: T): SuccessOrFailure<T> =
-            SuccessOrFailure(value)
+        public inline fun <T> success(value: T): Result<T> =
+            Result(value)
 
-        public inline fun <T> failure(exception: Throwable): SuccessOrFailure<T> =
-            SuccessOrFailure(Failure(exception))
+        public inline fun <T> failure(exception: Throwable): Result<T> =
+            Result(Failure(exception))
     }
 
     class Failure (
@@ -17,11 +17,11 @@ inline class SuccessOrFailure<out T>(val value: Any?) {
     )
 }
 
-inline fun <R> runCatching(block: () -> R): SuccessOrFailure<R> {
+inline fun <R> runCatching(block: () -> R): Result<R> {
     return try {
-        SuccessOrFailure.success(block())
+        Result.success(block())
     } catch (e: Throwable) {
-        SuccessOrFailure.failure(e)
+        Result.failure(e)
     }
 }
 

compiler/testData/codegen/boxInline/suspend/callableReference/ordinaryParameter.kt

@@ -20,7 +20,7 @@ fun builder(c: suspend () -> Unit) {
         override val context: CoroutineContext
             get() = EmptyCoroutineContext
 
-        override fun resumeWith(result: SuccessOrFailure<Unit>) {
+        override fun resumeWith(result: Result<Unit>) {
             result.getOrThrow()
         }
     })

compiler/testData/codegen/boxInline/suspend/callableReference/suspendOfOrdinary.kt

@@ -18,7 +18,7 @@ fun builder(c: suspend () -> Unit) {
         override val context: CoroutineContext
             get() = EmptyCoroutineContext
 
-        override fun resumeWith(result: SuccessOrFailure<Unit>) {
+        override fun resumeWith(result: Result<Unit>) {
             result.getOrThrow()
         }
     })

compiler/testData/codegen/boxInline/suspend/inlineUsedAsNoinline/inlineOnly.kt

@@ -38,7 +38,7 @@ fun builder(c: suspend () -> Unit) {
         override val context: CoroutineContext
             get() = EmptyCoroutineContext
 
-        override fun resumeWith(r: SuccessOrFailure<Unit>) {
+        override fun resumeWith(r: Result<Unit>) {
             r.getOrThrow()
             proceed = {
                 result = "OK"

compiler/testData/codegen/boxInline/suspend/inlineUsedAsNoinline/simpleNamed.kt

@@ -36,7 +36,7 @@ fun builder(c: suspend () -> Unit) {
         override val context: CoroutineContext
             get() = EmptyCoroutineContext
 
-        override fun resumeWith(r: SuccessOrFailure<Unit>) {
+        override fun resumeWith(r: Result<Unit>) {
             r.getOrThrow()
             proceed = {
                 result = "OK"

compiler/testData/codegen/bytecodeText/coroutines/doNotReassignContinuation.kt

@@ -4,7 +4,7 @@
 import kotlin.coroutines.*
 import kotlin.coroutines.intrinsics.*
 suspend fun suspendHere(): String = suspendCoroutineUninterceptedOrReturn { x ->
-    x.resumeWith(SuccessOrFailure.success("OK"))
+    x.resumeWith(Result.success("OK"))
 }
 
 suspend fun suspendThere(param: Int, param2: String, param3: Long): String {

compiler/testData/codegen/bytecodeText/inlineClasses/resultApiDoesntUseBox.kt

@@ -0,0 +1,37 @@
+// WITH_COROUTINES
+// FILE: test.kt
+fun test() {
+    val result = Result.success("yes!")
+    val failure = Result.failure<String>(Exception())
+
+    if (result.isSuccess) println("success")
+    if (result.isFailure) println("failure")
+    println(result.getOrThrow())
+    println(failure.getOrNull())
+    println(failure.exceptionOrNull())
+
+    val other = Result.success("nope")
+    if (result == other) println("==")
+    if (result != other) println("!=")
+    if (result.equals(other)) println("equals")
+    if (!result.equals(other)) println("!equals")
+
+    println(result.hashCode())
+    println(result.toString())
+    println("$result")
+
+    val ans1 = runCatching { 42 }
+    println(ans1)
+
+    val ans2 = 42.runCatching { this }
+    println(ans2)
+
+    println(result.getOrElse { "oops" })
+    println(result.getOrDefault("oops"))
+}
+
+// @TestKt.class:
+// 0 INVOKESTATIC Result.box-impl
+// 0 INVOKESTATIC Result.unbox-impl
+// 0 Result\$Failure
+// 53 Result

compiler/testData/codegen/bytecodeText/inlineClasses/successOrFailureApiDoesntUseErasedClass.kt

@@ -1,36 +0,0 @@
-// WITH_COROUTINES
-// FILE: test.kt
-fun testSoF() {
-    val sof = SuccessOrFailure.success("yes!")
-    val failure = SuccessOrFailure.failure<String>(Exception())
-
-    if (sof.isSuccess) println("success")
-    if (sof.isFailure) println("failure")
-    println(sof.getOrThrow())
-    println(failure.getOrNull())
-    println(failure.exceptionOrNull())
-
-    val other = SuccessOrFailure.success("nope")
-    if (sof == other) println("==")
-    if (sof != other) println("!=")
-    if (sof.equals(other)) println("equals")
-    if (!sof.equals(other)) println("!equals")
-
-    println(sof.hashCode())
-    println(sof.toString())
-    println("$sof")
-
-    val ans1 = runCatching { 42 }
-    println(ans1)
-
-    val ans2 = 42.runCatching { this }
-    println(ans2)
-
-    println(sof.getOrElse { "oops" })
-    println(sof.getOrDefault("oops"))
-}
-
-// @TestKt.class:
-// 0 SuccessOrFailure\$Erased
-// 0 SuccessOrFailure\-Erased
-// 58 SuccessOrFailure