From b8edc86500f3208b48663c16fd274dc316d8dc8b Mon Sep 17 00:00:00 2001
From: puddly <32534428+puddly@users.noreply.github.com>
Date: Wed, 26 Oct 2022 21:29:48 -0400
Subject: [PATCH] Handle sending ZCL commands with empty bitmap options
 (#81051)

Handle sending commands with empty bitmaps
---
 homeassistant/components/zha/core/helpers.py | 30 +++++++-------------
 tests/components/zha/test_helpers.py         | 14 +++++++++
 2 files changed, 24 insertions(+), 20 deletions(-)

diff --git a/homeassistant/components/zha/core/helpers.py b/homeassistant/components/zha/core/helpers.py
index 409d45789b5..1ea9a2a4c9b 100644
--- a/homeassistant/components/zha/core/helpers.py
+++ b/homeassistant/components/zha/core/helpers.py
@@ -14,7 +14,6 @@ import enum
 import functools
 import itertools
 import logging
-import operator
 from random import uniform
 import re
 from typing import TYPE_CHECKING, Any, TypeVar
@@ -163,25 +162,16 @@ def convert_to_zcl_values(
         if field.name not in fields:
             continue
         value = fields[field.name]
-        if issubclass(field.type, enum.Flag):
-            if isinstance(value, list):
-                value = field.type(
-                    functools.reduce(
-                        operator.ior,
-                        [
-                            field.type[flag.replace(" ", "_")]
-                            if isinstance(flag, str)
-                            else field.type(flag)
-                            for flag in value
-                        ],
-                    )
-                )
-            else:
-                value = (
-                    field.type[value.replace(" ", "_")]
-                    if isinstance(value, str)
-                    else field.type(value)
-                )
+        if issubclass(field.type, enum.Flag) and isinstance(value, list):
+            new_value = 0
+
+            for flag in value:
+                if isinstance(flag, str):
+                    new_value |= field.type[flag.replace(" ", "_")]
+                else:
+                    new_value |= flag
+
+            value = field.type(new_value)
         elif issubclass(field.type, enum.Enum):
             value = (
                 field.type[value.replace(" ", "_")]
diff --git a/tests/components/zha/test_helpers.py b/tests/components/zha/test_helpers.py
index f5fb5c4f5c0..64f8c732ca9 100644
--- a/tests/components/zha/test_helpers.py
+++ b/tests/components/zha/test_helpers.py
@@ -195,3 +195,17 @@ async def test_zcl_schema_conversions(hass, device_light):
 
     assert isinstance(converted_data["start_hue"], uint16_t)
     assert converted_data["start_hue"] == 196
+
+    # This time, the update flags bitmap is empty
+    raw_data = {
+        "update_flags": [],
+        "action": 0x02,
+        "direction": 0x01,
+        "time": 20,
+        "start_hue": 196,
+    }
+
+    converted_data = convert_to_zcl_values(raw_data, command_schema)
+
+    # No flags are passed through
+    assert converted_data["update_flags"] == 0