From 22c91dfadc5ba2bcf0c0c291eaf8b21c4d285274 Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@home-assistant.io>
Date: Sun, 14 Sep 2025 13:51:10 -0500
Subject: [PATCH] cleanup

---
 esphome/components/md5/md5.cpp | 6 ++----
 esphome/core/helpers.cpp       | 1 -
 esphome/core/helpers.h         | 3 +++
 3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/esphome/components/md5/md5.cpp b/esphome/components/md5/md5.cpp
index fb0d9f401f..21bd2e1cab 100644
--- a/esphome/components/md5/md5.cpp
+++ b/esphome/components/md5/md5.cpp
@@ -44,10 +44,8 @@ void MD5Digest::get_bytes(uint8_t *output) { memcpy(output, this->digest_, 16);
 void MD5Digest::get_hex(char *output) {
   for (size_t i = 0; i < 16; i++) {
     uint8_t byte = this->digest_[i];
-    uint8_t high = byte >> 4;
-    uint8_t low = byte & 0x0F;
-    output[i * 2] = high < 10 ? '0' + high : 'a' + (high - 10);
-    output[i * 2 + 1] = low < 10 ? '0' + low : 'a' + (low - 10);
+    output[i * 2] = format_hex_char(byte >> 4);
+    output[i * 2 + 1] = format_hex_char(byte & 0x0F);
   }
 }
 
diff --git a/esphome/core/helpers.cpp b/esphome/core/helpers.cpp
index 43d6f1153c..7f977c5d40 100644
--- a/esphome/core/helpers.cpp
+++ b/esphome/core/helpers.cpp
@@ -258,7 +258,6 @@ std::string format_mac_address_pretty(const uint8_t *mac) {
   return str_snprintf("%02X:%02X:%02X:%02X:%02X:%02X", 17, mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
 }
 
-static char format_hex_char(uint8_t v) { return v >= 10 ? 'a' + (v - 10) : '0' + v; }
 std::string format_hex(const uint8_t *data, size_t length) {
   std::string ret;
   ret.resize(length * 2);
diff --git a/esphome/core/helpers.h b/esphome/core/helpers.h
index a6741925d0..a2bac19b25 100644
--- a/esphome/core/helpers.h
+++ b/esphome/core/helpers.h
@@ -380,6 +380,9 @@ template<typename T, enable_if_t<std::is_unsigned<T>::value, int> = 0> optional<
   return parse_hex<T>(str.c_str(), str.length());
 }
 
+/// Convert a nibble (0-15) to lowercase hex char
+inline char format_hex_char(uint8_t v) { return v >= 10 ? 'a' + (v - 10) : '0' + v; }
+
 /// Format the six-byte array \p mac into a MAC address.
 std::string format_mac_address_pretty(const uint8_t mac[6]);
 /// Format the byte array \p data of length \p len in lowercased hex.