From f4ec905aff72837ff3dbc6756caddf3d3aa657f4 Mon Sep 17 00:00:00 2001
From: Him188 <Him188@mamoe.net>
Date: Wed, 16 Jun 2021 01:51:26 +0800
Subject: [PATCH] Make `CombinedStateObserver.toString` more readable

---
 .../network/handler/state/CombinedStateObserver.kt    | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/mirai-core/src/commonMain/kotlin/network/handler/state/CombinedStateObserver.kt b/mirai-core/src/commonMain/kotlin/network/handler/state/CombinedStateObserver.kt
index 0587e35bc..6c341be82 100644
--- a/mirai-core/src/commonMain/kotlin/network/handler/state/CombinedStateObserver.kt
+++ b/mirai-core/src/commonMain/kotlin/network/handler/state/CombinedStateObserver.kt
@@ -49,7 +49,16 @@ internal class CombinedStateObserver(
     }
 
     override fun toString(): String {
-        return "CombinedStateObserver(first=$first, last=$last)"
+        return asSequence().joinToString(
+            prefix = "CombinedStateObserver[",
+            postfix = "]",
+            separator = " -> "
+        ) { it.toString() }
+    }
+
+    private fun asSequence(): Sequence<StateObserver> = sequence {
+        if (first is CombinedStateObserver) yieldAll(first.asSequence()) else yield(first)
+        if (last is CombinedStateObserver) yieldAll(last.asSequence()) else yield(last)
     }
 
     companion object {