From 60ae3c15c826f6cc5ca961a550fbbf44794058cb Mon Sep 17 00:00:00 2001
From: Thales Macedo Garitezi <thalesmg@gmail.com>
Date: Mon, 4 Sep 2023 14:06:13 -0300
Subject: [PATCH] refactor: disregard impossible case

---
 apps/emqx/src/emqx_persistent_session_ds.erl | 15 +++++----------
 apps/emqx/src/emqx_session.erl               |  9 +++++++--
 2 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/apps/emqx/src/emqx_persistent_session_ds.erl b/apps/emqx/src/emqx_persistent_session_ds.erl
index 13c35ed9b..43ca8bc02 100644
--- a/apps/emqx/src/emqx_persistent_session_ds.erl
+++ b/apps/emqx/src/emqx_persistent_session_ds.erl
@@ -146,16 +146,11 @@ del_subscription(IteratorID, TopicFilterBin, DSSessionID) ->
         begin
             TopicFilter = emqx_topic:words(TopicFilterBin),
             Ctx = #{iterator_id => IteratorID},
-            case IteratorID of
-                undefined ->
-                    ok;
-                _ ->
-                    ?tp_span(
-                        persistent_session_ds_close_iterators,
-                        Ctx,
-                        ok = ensure_iterator_closed_on_all_shards(IteratorID)
-                    )
-            end,
+            ?tp_span(
+                persistent_session_ds_close_iterators,
+                Ctx,
+                ok = ensure_iterator_closed_on_all_shards(IteratorID)
+            ),
             ?tp_span(
                 persistent_session_ds_iterator_delete,
                 Ctx,
diff --git a/apps/emqx/src/emqx_session.erl b/apps/emqx/src/emqx_session.erl
index 1ff4d9b85..859cee76b 100644
--- a/apps/emqx/src/emqx_session.erl
+++ b/apps/emqx/src/emqx_session.erl
@@ -357,8 +357,13 @@ unsubscribe(
     session().
 remove_persistent_subscription(Session, TopicFilterBin, ClientId) ->
     Iterators = Session#session.iterators,
-    IteratorId = maps:get(TopicFilterBin, Iterators, undefined),
-    _ = emqx_persistent_session_ds:del_subscription(IteratorId, TopicFilterBin, ClientId),
+    case maps:get(TopicFilterBin, Iterators, undefined) of
+        undefined ->
+            ok;
+        IteratorId ->
+            _ = emqx_persistent_session_ds:del_subscription(IteratorId, TopicFilterBin, ClientId),
+            ok
+    end,
     Session#session{iterators = maps:remove(TopicFilterBin, Iterators)}.
 
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