refactor: made code more readable thanks to suggestion from @zmstone

apps/emqx_resource/src/emqx_resource_buffer_worker.erl

@@ -585,7 +585,7 @@ flush(Data0) ->
             ?tp(buffer_worker_flush_before_pop, #{}),
             PopOpts = #{
                 count_limit => BatchSize,
-                stop_before => {fun stop_before_mixed_stop_after_render/2, initial_state}
+                stop_before => {fun stop_batching/2, initial_state}
             },
             {Q1, QAckRef, Batch} = replayq:pop(Q0, PopOpts),
             Data2 = Data1#{queue := Q1},
@@ -623,72 +623,22 @@ flush(Data0) ->
             end
     end.
 
-stop_before_mixed_stop_after_render(
-    ?QUERY(
-        _,
-        _,
-        _,
-        _,
-        #{stop_action_after_render := true} = _TraceCtx
-    ),
-    initial_state
-) ->
-    stop_action_after_render;
-stop_before_mixed_stop_after_render(
-    ?QUERY(
-        _,
-        _,
-        _,
-        _,
-        _TraceCtx
-    ),
-    initial_state
-) ->
-    no_stop_action_after_render;
-stop_before_mixed_stop_after_render(
-    ?QUERY(
-        _,
-        _,
-        _,
-        _,
-        #{stop_action_after_render := true} = _TraceCtx
-    ),
-    no_stop_action_after_render
-) ->
-    true;
-stop_before_mixed_stop_after_render(
-    ?QUERY(
-        _,
-        _,
-        _,
-        _,
-        #{stop_action_after_render := true} = _TraceCtx
-    ),
-    stop_action_after_render
-) ->
+stop_batching(Query, initial_state) ->
+    get_stop_flag(Query);
+stop_batching(Query, PrevStopFlag) ->
+    case get_stop_flag(Query) =:= PrevStopFlag of
+        true ->
+            PrevStopFlag;
+        false ->
+            %% We stop beceause we don't want a batch with mixed values for the
+            %% stop_action_after_render option
+            true
+    end.
+
+get_stop_flag(?QUERY(_, _, _, _, #{stop_action_after_render := true})) ->
     stop_action_after_render;
-stop_before_mixed_stop_after_render(
-    ?QUERY(
-        _,
-        _,
-        _,
-        _,
-        _TraceCtx
-    ),
-    stop_action_after_render
-) ->
-    true;
-stop_before_mixed_stop_after_render(
-    ?QUERY(
-        _,
-        _,
-        _,
-        _,
-        _TraceCtx
-    ),
-    State
-) ->
-    State.
+get_stop_flag(_) ->
+    no_stop_action_after_render.
 
 -spec do_flush(data(), #{
     is_batch := boolean(),