From e80f967ebb3de801acc27060cf11fcb80f7f9ee2 Mon Sep 17 00:00:00 2001
From: "hoc081098@gmail.com" <hoc081098@gmail.com>
Date: Sun, 27 Apr 2025 22:24:10 +0700
Subject: [PATCH] Add UnsafeResultValueAccess annotation to Result class for
 safer value access

---
 .../main/kotlin/kotlin-conventions.gradle.kts  |  1 +
 .../com/github/michaelbull/result/Result.kt    | 18 ++++++++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/buildSrc/src/main/kotlin/kotlin-conventions.gradle.kts b/buildSrc/src/main/kotlin/kotlin-conventions.gradle.kts
index 6e94e33..dafcb00 100644
--- a/buildSrc/src/main/kotlin/kotlin-conventions.gradle.kts
+++ b/buildSrc/src/main/kotlin/kotlin-conventions.gradle.kts
@@ -59,6 +59,7 @@ kotlin {
         all {
             languageSettings.apply {
                 optIn("kotlin.contracts.ExperimentalContracts")
+                optIn("com.github.michaelbull.result.UnsafeResultValueAccess")
             }
         }
 
diff --git a/kotlin-result/src/commonMain/kotlin/com/github/michaelbull/result/Result.kt b/kotlin-result/src/commonMain/kotlin/com/github/michaelbull/result/Result.kt
index 804c926..aa7b689 100644
--- a/kotlin-result/src/commonMain/kotlin/com/github/michaelbull/result/Result.kt
+++ b/kotlin-result/src/commonMain/kotlin/com/github/michaelbull/result/Result.kt
@@ -51,10 +51,12 @@ public value class Result<out V, out E> internal constructor(
     private val inlineValue: Any?,
 ) {
 
+    @UnsafeResultValueAccess
     @Suppress("UNCHECKED_CAST")
     public val value: V
         get() = inlineValue as V
 
+    @UnsafeResultValueAccess
     @Suppress("UNCHECKED_CAST")
     public val error: E
         get() = (inlineValue as Failure<E>).error
@@ -102,3 +104,19 @@ private class Failure<out E>(
         return "Failure($error)"
     }
 }
+
+/**
+ * Marks access to [Result.value] or [Result.error] as potentially unsafe unless the [Result]
+ * is explicitly checked for [Result.isOk] or [Result.isErr] beforehand.
+ *
+ * Ensure that you verify the [Result] state using [Result.isOk] or [Result.isErr] before accessing its value.
+ * Alternatively, consider using the [Result.fold] function to safely handle the result.
+ */
+@RequiresOptIn(
+    level = RequiresOptIn.Level.ERROR,
+    message = "Accessing Result.value or Result.error without checking the Result state may lead to unsafe behavior.",
+)
+@MustBeDocumented
+@Retention(AnnotationRetention.BINARY)
+@Target(AnnotationTarget.PROPERTY)
+public annotation class UnsafeResultValueAccess