diff --git a/binary-compatibility-validator/api/binary-compatibility-validator.api b/binary-compatibility-validator/api/binary-compatibility-validator.api
index 259978db9..c6342ef95 100644
--- a/binary-compatibility-validator/api/binary-compatibility-validator.api
+++ b/binary-compatibility-validator/api/binary-compatibility-validator.api
@@ -579,6 +579,11 @@ public abstract interface class net/mamoe/mirai/contact/Stranger : kotlinx/corou
 	public fun uploadImage (Lnet/mamoe/mirai/utils/ExternalResource;)Lnet/mamoe/mirai/message/data/Image;
 }
 
+public final class net/mamoe/mirai/contact/StrangerKt {
+	public static final fun asFriend (Lnet/mamoe/mirai/contact/Stranger;)Lnet/mamoe/mirai/contact/Friend;
+	public static final fun asFriendOrNull (Lnet/mamoe/mirai/contact/Stranger;)Lnet/mamoe/mirai/contact/Friend;
+}
+
 public abstract interface class net/mamoe/mirai/contact/TempUser : net/mamoe/mirai/contact/User {
 	public fun queryProfile ()Lnet/mamoe/mirai/data/UserProfile;
 	public fun sendMessage (Ljava/lang/String;)Lnet/mamoe/mirai/message/MessageReceipt;
diff --git a/mirai-core-api/src/commonMain/kotlin/contact/Stranger.kt b/mirai-core-api/src/commonMain/kotlin/contact/Stranger.kt
index 1adc68253..cee50b1bb 100644
--- a/mirai-core-api/src/commonMain/kotlin/contact/Stranger.kt
+++ b/mirai-core-api/src/commonMain/kotlin/contact/Stranger.kt
@@ -91,4 +91,19 @@ public interface Stranger : User, CoroutineScope {
      * @see Nudge.sendTo 发送这个戳一戳消息
      */
     public override fun nudge(): StrangerNudge = StrangerNudge(this)
-}
\ No newline at end of file
+}
+
+
+/**
+ * 得到此陌生人作为好友的对象.
+ *
+ * @throws IllegalStateException 当此成员不是好友时抛出
+ * @since 2.2
+ */
+public fun Stranger.asFriend(): Friend = this.bot.getFriend(this.id) ?: error("$this is not a friend")
+
+/**
+ * 得到此陌生人作为好友的对象, 当此成员不是好友时返回 `null`
+ * @since 2.2
+ */
+public fun Stranger.asFriendOrNull(): Friend? = this.bot.getFriend(this.id)