From f5fc06fd9e5323403b51e0a13beaecc1c7fc091f Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@home-assistant.io>
Date: Thu, 2 Oct 2025 23:03:53 +0200
Subject: [PATCH] preen

---
 esphome/core/helpers.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/esphome/core/helpers.cpp b/esphome/core/helpers.cpp
index 2c65bec6e6..33916515d8 100644
--- a/esphome/core/helpers.cpp
+++ b/esphome/core/helpers.cpp
@@ -366,7 +366,9 @@ std::string value_accuracy_to_string(float value, int8_t accuracy_decimals) {
 
 std::string value_accuracy_with_uom_to_string(float value, int8_t accuracy_decimals, StringRef unit_of_measurement) {
   normalize_accuracy_decimals(value, accuracy_decimals);
-  char tmp[64];  // Increased to accommodate unit of measurement
+  // Buffer sized for float (up to ~15 chars) + space + typical UOM (usually <20 chars like "μS/cm")
+  // snprintf truncates safely if exceeded, though ESPHome UOMs are typically short
+  char tmp[64];
   if (unit_of_measurement.empty()) {
     snprintf(tmp, sizeof(tmp), "%.*f", accuracy_decimals, value);
   } else {