From dbc2078b2e817209894107c5fb4331fe86fd6ce4 Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@home-assistant.io>
Date: Thu, 27 Nov 2025 18:27:27 -0600
Subject: [PATCH] assert

---
 esphome/components/api/homeassistant_service.h | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/esphome/components/api/homeassistant_service.h b/esphome/components/api/homeassistant_service.h
index 01e53031e7..fbfd94398a 100644
--- a/esphome/components/api/homeassistant_service.h
+++ b/esphome/components/api/homeassistant_service.h
@@ -16,6 +16,12 @@
 namespace esphome::api {
 
 template<typename... X> class TemplatableStringValue : public TemplatableValue<std::string, X...> {
+  // Verify that const char* uses the base class STATIC_STRING optimization (no heap allocation)
+  // rather than being wrapped in a lambda. The base class constructor for const char* is more
+  // specialized than the templated constructor here, so it should be selected.
+  static_assert(std::is_constructible_v<TemplatableValue<std::string, X...>, const char *>,
+                "Base class must have const char* constructor for STATIC_STRING optimization");
+
  private:
   // Helper to convert value to string - handles the case where value is already a string
   template<typename T> static std::string value_to_string(T &&val) { return to_string(std::forward<T>(val)); }