[select] Return StringRef from current_option() (#13095)

esphome/components/api/api_connection.cpp

@@ -914,7 +914,7 @@ uint16_t APIConnection::try_send_select_state(EntityBase *entity, APIConnection
                                               bool is_single) {
   auto *select = static_cast<select::Select *>(entity);
   SelectStateResponse resp;
-  resp.state = StringRef(select->current_option());
+  resp.state = select->current_option();
   resp.missing_state = !select->has_state();
   return fill_and_encode_entity_state(select, resp, SelectStateResponse::MESSAGE_TYPE, conn, remaining_size, is_single);
 }

esphome/components/display_menu_base/menu_item.cpp

@@ -42,7 +42,8 @@ std::string MenuItemSelect::get_value_text() const {
     result = this->value_getter_.value()(this);
   } else {
     if (this->select_var_ != nullptr) {
-      result = this->select_var_->current_option();
+      auto option = this->select_var_->current_option();
+      result.assign(option.c_str(), option.size());
     }
   }
 

esphome/components/ld2410/ld2410.cpp

@@ -442,7 +442,8 @@ bool LD2410Component::handle_ack_data_() {
       ESP_LOGV(TAG, "Baud rate change");
 #ifdef USE_SELECT
       if (this->baud_rate_select_ != nullptr) {
-        ESP_LOGE(TAG, "Change baud rate to %s and reinstall", this->baud_rate_select_->current_option());
+        auto baud = this->baud_rate_select_->current_option();
+        ESP_LOGE(TAG, "Change baud rate to %.*s and reinstall", (int) baud.size(), baud.c_str());
       }
 #endif
       break;
@@ -766,10 +767,10 @@ void LD2410Component::set_light_out_control() {
 #endif
 #ifdef USE_SELECT
   if (this->light_function_select_ != nullptr && this->light_function_select_->has_state()) {
-    this->light_function_ = find_uint8(LIGHT_FUNCTIONS_BY_STR, this->light_function_select_->current_option());
+    this->light_function_ = find_uint8(LIGHT_FUNCTIONS_BY_STR, this->light_function_select_->current_option().c_str());
   }
   if (this->out_pin_level_select_ != nullptr && this->out_pin_level_select_->has_state()) {
-    this->out_pin_level_ = find_uint8(OUT_PIN_LEVELS_BY_STR, this->out_pin_level_select_->current_option());
+    this->out_pin_level_ = find_uint8(OUT_PIN_LEVELS_BY_STR, this->out_pin_level_select_->current_option().c_str());
   }
 #endif
   this->set_config_mode_(true);

esphome/components/ld2412/ld2412.cpp

@@ -486,7 +486,8 @@ bool LD2412Component::handle_ack_data_() {
       ESP_LOGV(TAG, "Baud rate change");
 #ifdef USE_SELECT
       if (this->baud_rate_select_ != nullptr) {
-        ESP_LOGW(TAG, "Change baud rate to %s and reinstall", this->baud_rate_select_->current_option());
+        auto baud = this->baud_rate_select_->current_option();
+        ESP_LOGW(TAG, "Change baud rate to %.*s and reinstall", (int) baud.size(), baud.c_str());
       }
 #endif
       break;
@@ -790,7 +791,7 @@ void LD2412Component::set_basic_config() {
       1,    TOTAL_GATES, DEFAULT_PRESENCE_TIMEOUT, 0,
 #endif
 #ifdef USE_SELECT
-      find_uint8(OUT_PIN_LEVELS_BY_STR, this->out_pin_level_select_->current_option()),
+      find_uint8(OUT_PIN_LEVELS_BY_STR, this->out_pin_level_select_->current_option().c_str()),
 #else
       0x01,  // Default value if not using select
 #endif
@@ -844,7 +845,7 @@ void LD2412Component::set_light_out_control() {
 #endif
 #ifdef USE_SELECT
   if (this->light_function_select_ != nullptr && this->light_function_select_->has_state()) {
-    this->light_function_ = find_uint8(LIGHT_FUNCTIONS_BY_STR, this->light_function_select_->current_option());
+    this->light_function_ = find_uint8(LIGHT_FUNCTIONS_BY_STR, this->light_function_select_->current_option().c_str());
   }
 #endif
   uint8_t value[2] = {this->light_function_, this->light_threshold_};

esphome/components/ld2450/ld2450.cpp

@@ -637,7 +637,8 @@ bool LD2450Component::handle_ack_data_() {
       ESP_LOGV(TAG, "Baud rate change");
 #ifdef USE_SELECT
       if (this->baud_rate_select_ != nullptr) {
-        ESP_LOGE(TAG, "Change baud rate to %s and reinstall", this->baud_rate_select_->current_option());
+        auto baud = this->baud_rate_select_->current_option();
+        ESP_LOGE(TAG, "Change baud rate to %.*s and reinstall", (int) baud.size(), baud.c_str());
       }
 #endif
       break;
@@ -718,7 +719,8 @@ bool LD2450Component::handle_ack_data_() {
       this->publish_zone_type();
 #ifdef USE_SELECT
       if (this->zone_type_select_ != nullptr) {
-        ESP_LOGV(TAG, "Change zone type to: %s", this->zone_type_select_->current_option());
+        auto zone = this->zone_type_select_->current_option();
+        ESP_LOGV(TAG, "Change zone type to: %.*s", (int) zone.size(), zone.c_str());
       }
 #endif
       if (this->buffer_data_[10] == 0x00) {

esphome/components/mqtt/mqtt_select.cpp

@@ -43,7 +43,8 @@ void MQTTSelectComponent::send_discovery(JsonObject root, mqtt::SendDiscoveryCon
 }
 bool MQTTSelectComponent::send_initial_state() {
   if (this->select_->has_state()) {
-    return this->publish_state(this->select_->current_option());
+    auto option = this->select_->current_option();
+    return this->publish_state(std::string(option.c_str(), option.size()));
   } else {
     return true;
   }

esphome/components/prometheus/prometheus_handler.cpp

@@ -709,7 +709,8 @@ void PrometheusHandler::select_row_(AsyncResponseStream *stream, select::Select
     stream->print(ESPHOME_F("\",name=\""));
     stream->print(relabel_name_(obj).c_str());
     stream->print(ESPHOME_F("\",value=\""));
-    stream->print(obj->current_option());
+    // c_str() is safe as option values are null-terminated strings from codegen
+    stream->print(obj->current_option().c_str());
     stream->print(ESPHOME_F("\"} "));
     stream->print(ESPHOME_F("1.0"));
     stream->print(ESPHOME_F("\n"));

esphome/components/select/select.cpp

@@ -38,7 +38,9 @@ void Select::publish_state(size_t index) {
 #endif
 }
 
-const char *Select::current_option() const { return this->has_state() ? this->option_at(this->active_index_) : ""; }
+StringRef Select::current_option() const {
+  return this->has_state() ? StringRef(this->option_at(this->active_index_)) : StringRef();
+}
 
 void Select::add_on_state_callback(std::function<void(size_t)> &&callback) {
   this->state_callback_.add(std::move(callback));

esphome/components/select/select.h

@@ -3,6 +3,7 @@
 #include "esphome/core/component.h"
 #include "esphome/core/entity_base.h"
 #include "esphome/core/helpers.h"
+#include "esphome/core/string_ref.h"
 #include "select_call.h"
 #include "select_traits.h"
 
@@ -33,8 +34,8 @@ class Select : public EntityBase {
 
 #pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
-  /// @deprecated Use current_option() instead. This member will be removed in ESPHome 2026.5.0.
+  /// @deprecated Use current_option() instead. This member will be removed in ESPHome 2026.7.0.
-  ESPDEPRECATED("Use current_option() instead of .state. Will be removed in 2026.5.0", "2025.11.0")
+  ESPDEPRECATED("Use current_option() instead of .state. Will be removed in 2026.7.0", "2026.1.0")
   std::string state{};
 
   Select() = default;
@@ -45,8 +46,10 @@ class Select : public EntityBase {
   void publish_state(const char *state);
   void publish_state(size_t index);
 
-  /// Return the currently selected option (as const char* from flash).
+  /// Return the currently selected option, or empty StringRef if no state.
-  const char *current_option() const;
+  /// The returned StringRef points to string literals from codegen (static storage).
+  /// Traits are set once at startup and valid for the lifetime of the program.
+  StringRef current_option() const;
 
   /// Instantiate a SelectCall object to modify this select component's state.
   SelectCall make_call() { return SelectCall(this); }

esphome/components/web_server/web_server.cpp

@@ -1393,7 +1393,7 @@ void WebServer::handle_select_request(AsyncWebServerRequest *request, const UrlM
 
     if (request->method() == HTTP_GET && entity_match.action_is_empty) {
       auto detail = get_request_detail(request);
-      std::string data = this->select_json_(obj, obj->has_state() ? obj->current_option() : "", detail);
+      std::string data = this->select_json_(obj, obj->has_state() ? obj->current_option() : StringRef(), detail);
       request->send(200, "application/json", data.c_str());
       return;
     }
@@ -1414,17 +1414,18 @@ void WebServer::handle_select_request(AsyncWebServerRequest *request, const UrlM
 }
 std::string WebServer::select_state_json_generator(WebServer *web_server, void *source) {
   auto *obj = (select::Select *) (source);
-  return web_server->select_json_(obj, obj->has_state() ? obj->current_option() : "", DETAIL_STATE);
+  return web_server->select_json_(obj, obj->has_state() ? obj->current_option() : StringRef(), DETAIL_STATE);
 }
 std::string WebServer::select_all_json_generator(WebServer *web_server, void *source) {
   auto *obj = (select::Select *) (source);
-  return web_server->select_json_(obj, obj->has_state() ? obj->current_option() : "", DETAIL_ALL);
+  return web_server->select_json_(obj, obj->has_state() ? obj->current_option() : StringRef(), DETAIL_ALL);
 }
-std::string WebServer::select_json_(select::Select *obj, const char *value, JsonDetail start_config) {
+std::string WebServer::select_json_(select::Select *obj, StringRef value, JsonDetail start_config) {
   json::JsonBuilder builder;
   JsonObject root = builder.root();
 
-  set_json_icon_state_value(root, obj, "select", value, value, start_config);
+  // value points to null-terminated string literals from codegen (via current_option())
+  set_json_icon_state_value(root, obj, "select", value.c_str(), value.c_str(), start_config);
   if (start_config == DETAIL_ALL) {
     JsonArray opt = root[ESPHOME_F("option")].to<JsonArray>();
     for (auto &option : obj->traits.get_options()) {

esphome/components/web_server/web_server.h

@@ -627,7 +627,7 @@ class WebServer : public Controller,
   std::string text_json_(text::Text *obj, const std::string &value, JsonDetail start_config);
 #endif
 #ifdef USE_SELECT
-  std::string select_json_(select::Select *obj, const char *value, JsonDetail start_config);
+  std::string select_json_(select::Select *obj, StringRef value, JsonDetail start_config);
 #endif
 #ifdef USE_CLIMATE
   std::string climate_json_(climate::Climate *obj, JsonDetail start_config);

tests/components/template/common-base.yaml

@@ -243,6 +243,7 @@ number:
 
 select:
   - platform: template
+    id: template_select
     name: "Template select"
     optimistic: true
     options:
@@ -250,6 +251,37 @@ select:
       - two
       - three
     initial_option: two
+    # Test current_option() returning std::string_view - migration guide examples
+    on_value:
+      - lambda: |-
+          // Migration guide: Check if select has a state
+          // OLD: if (id(template_select).current_option() != nullptr)
+          // NEW: Check with .empty()
+          if (!id(template_select).current_option().empty()) {
+            ESP_LOGI("test", "Select has state");
+          }
+
+          // Migration guide: Compare option values
+          // OLD: if (strcmp(id(template_select).current_option(), "one") == 0)
+          // NEW: Direct comparison works safely even when empty
+          if (id(template_select).current_option() == "one") {
+            ESP_LOGI("test", "Option is 'one'");
+          }
+          if (id(template_select).current_option() != "two") {
+            ESP_LOGI("test", "Option is not 'two'");
+          }
+
+          // Migration guide: Logging options
+          // Option 1: Using .c_str() - StringRef guarantees null-termination
+          ESP_LOGI("test", "Current option: %s", id(template_select).current_option().c_str());
+
+          // Option 2: Using %.*s format with size
+          auto option = id(template_select).current_option();
+          ESP_LOGI("test", "Current option (safe): %.*s", (int) option.size(), option.c_str());
+
+          // Migration guide: Store in std::string
+          std::string stored_option(id(template_select).current_option());
+          ESP_LOGI("test", "Stored: %s", stored_option.c_str());
 
 lock:
   - platform: template