From df53ff7afed11a1fc18ad03484d77c9c64bf1024 Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@koston.org>
Date: Wed, 5 Nov 2025 12:13:12 -0600
Subject: [PATCH 1/8] [scheduler] Extract helper functions to improve code
 readability (#11730)

---
 esphome/core/scheduler.cpp | 45 ++++++++++++++++++++------------------
 esphome/core/scheduler.h   | 34 ++++++++++++++++++++--------
 2 files changed, 49 insertions(+), 30 deletions(-)

diff --git a/esphome/core/scheduler.cpp b/esphome/core/scheduler.cpp
index 11d59c2499..d285af2d0e 100644
--- a/esphome/core/scheduler.cpp
+++ b/esphome/core/scheduler.cpp
@@ -117,12 +117,8 @@ void HOT Scheduler::set_timer_common_(Component *component, SchedulerItem::Type
   item->set_name(name_cstr, !is_static_string);
   item->type = type;
   item->callback = std::move(func);
-  // Initialize remove to false (though it should already be from constructor)
-#ifdef ESPHOME_THREAD_MULTI_ATOMICS
-  item->remove.store(false, std::memory_order_relaxed);
-#else
-  item->remove = false;
-#endif
+  // Reset remove flag - recycled items may have been cancelled (remove=true) in previous use
+  this->set_item_removed_(item.get(), false);
   item->is_retry = is_retry;
 
 #ifndef ESPHOME_THREAD_SINGLE
@@ -153,21 +149,7 @@ void HOT Scheduler::set_timer_common_(Component *component, SchedulerItem::Type
   }
 
 #ifdef ESPHOME_DEBUG_SCHEDULER
-  // Validate static strings in debug mode
-  if (is_static_string && name_cstr != nullptr) {
-    validate_static_string(name_cstr);
-  }
-
-  // Debug logging
-  const char *type_str = (type == SchedulerItem::TIMEOUT) ? "timeout" : "interval";
-  if (type == SchedulerItem::TIMEOUT) {
-    ESP_LOGD(TAG, "set_%s(name='%s/%s', %s=%" PRIu32 ")", type_str, LOG_STR_ARG(item->get_source()),
-             name_cstr ? name_cstr : "(null)", type_str, delay);
-  } else {
-    ESP_LOGD(TAG, "set_%s(name='%s/%s', %s=%" PRIu32 ", offset=%" PRIu32 ")", type_str, LOG_STR_ARG(item->get_source()),
-             name_cstr ? name_cstr : "(null)", type_str, delay,
-             static_cast<uint32_t>(item->get_next_execution() - now));
-  }
+  this->debug_log_timer_(item.get(), is_static_string, name_cstr, type, delay, now);
 #endif /* ESPHOME_DEBUG_SCHEDULER */
 
   // For retries, check if there's a cancelled timeout first
@@ -787,4 +769,25 @@ void Scheduler::recycle_item_(std::unique_ptr<SchedulerItem> item) {
   // else: unique_ptr will delete the item when it goes out of scope
 }
 
+#ifdef ESPHOME_DEBUG_SCHEDULER
+void Scheduler::debug_log_timer_(const SchedulerItem *item, bool is_static_string, const char *name_cstr,
+                                 SchedulerItem::Type type, uint32_t delay, uint64_t now) {
+  // Validate static strings in debug mode
+  if (is_static_string && name_cstr != nullptr) {
+    validate_static_string(name_cstr);
+  }
+
+  // Debug logging
+  const char *type_str = (type == SchedulerItem::TIMEOUT) ? "timeout" : "interval";
+  if (type == SchedulerItem::TIMEOUT) {
+    ESP_LOGD(TAG, "set_%s(name='%s/%s', %s=%" PRIu32 ")", type_str, LOG_STR_ARG(item->get_source()),
+             name_cstr ? name_cstr : "(null)", type_str, delay);
+  } else {
+    ESP_LOGD(TAG, "set_%s(name='%s/%s', %s=%" PRIu32 ", offset=%" PRIu32 ")", type_str, LOG_STR_ARG(item->get_source()),
+             name_cstr ? name_cstr : "(null)", type_str, delay,
+             static_cast<uint32_t>(item->get_next_execution() - now));
+  }
+}
+#endif /* ESPHOME_DEBUG_SCHEDULER */
+
 }  // namespace esphome
diff --git a/esphome/core/scheduler.h b/esphome/core/scheduler.h
index f6ec07294d..fd16840240 100644
--- a/esphome/core/scheduler.h
+++ b/esphome/core/scheduler.h
@@ -266,6 +266,12 @@ class Scheduler {
   // Helper to perform full cleanup when too many items are cancelled
   void full_cleanup_removed_items_();
 
+#ifdef ESPHOME_DEBUG_SCHEDULER
+  // Helper for debug logging in set_timer_common_ - extracted to reduce code size
+  void debug_log_timer_(const SchedulerItem *item, bool is_static_string, const char *name_cstr,
+                        SchedulerItem::Type type, uint32_t delay, uint64_t now);
+#endif /* ESPHOME_DEBUG_SCHEDULER */
+
 #ifndef ESPHOME_THREAD_SINGLE
   // Helper to process defer queue - inline for performance in hot path
   inline void process_defer_queue_(uint32_t &now) {
@@ -367,6 +373,24 @@ class Scheduler {
 #endif
   }
 
+  // Helper to set item removal flag (platform-specific)
+  // For ESPHOME_THREAD_MULTI_NO_ATOMICS platforms, the caller must hold the scheduler lock before calling this
+  // function. Uses memory_order_release when setting to true (for cancellation synchronization),
+  // and memory_order_relaxed when setting to false (for initialization).
+  void set_item_removed_(SchedulerItem *item, bool removed) {
+#ifdef ESPHOME_THREAD_MULTI_ATOMICS
+    // Multi-threaded with atomics: use atomic store with appropriate ordering
+    // Release ordering when setting to true ensures cancellation is visible to other threads
+    // Relaxed ordering when setting to false is sufficient for initialization
+    item->remove.store(removed, removed ? std::memory_order_release : std::memory_order_relaxed);
+#else
+    // Single-threaded (ESPHOME_THREAD_SINGLE) or
+    // multi-threaded without atomics (ESPHOME_THREAD_MULTI_NO_ATOMICS): direct write
+    // For ESPHOME_THREAD_MULTI_NO_ATOMICS, caller MUST hold lock!
+    item->remove = removed;
+#endif
+  }
+
   // Helper to mark matching items in a container as removed
   // Returns the number of items marked for removal
   // IMPORTANT: Caller must hold the scheduler lock before calling this function.
@@ -383,15 +407,7 @@ class Scheduler {
         continue;
       if (this->matches_item_(item, component, name_cstr, type, match_retry)) {
         // Mark item for removal (platform-specific)
-#ifdef ESPHOME_THREAD_MULTI_ATOMICS
-        // Multi-threaded with atomics: use atomic store
-        item->remove.store(true, std::memory_order_release);
-#else
-        // Single-threaded (ESPHOME_THREAD_SINGLE) or
-        // multi-threaded without atomics (ESPHOME_THREAD_MULTI_NO_ATOMICS): direct write
-        // For ESPHOME_THREAD_MULTI_NO_ATOMICS, caller MUST hold lock!
-        item->remove = true;
-#endif
+        this->set_item_removed_(item.get(), true);
         count++;
       }
     }

From d36ef050a90d09a87e22b2cc5866b52007e9c875 Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@koston.org>
Date: Wed, 5 Nov 2025 12:15:50 -0600
Subject: [PATCH 2/8] [template] Mark all component classes as final (#11733)

---
 .../alarm_control_panel/template_alarm_control_panel.h        | 2 +-
 .../template/binary_sensor/template_binary_sensor.h           | 2 +-
 esphome/components/template/button/template_button.h          | 2 +-
 esphome/components/template/cover/template_cover.h            | 2 +-
 esphome/components/template/datetime/template_date.h          | 2 +-
 esphome/components/template/datetime/template_datetime.h      | 2 +-
 esphome/components/template/datetime/template_time.h          | 2 +-
 esphome/components/template/event/template_event.h            | 2 +-
 esphome/components/template/fan/template_fan.h                | 2 +-
 esphome/components/template/lock/template_lock.h              | 2 +-
 esphome/components/template/number/template_number.h          | 2 +-
 esphome/components/template/output/template_output.h          | 4 ++--
 esphome/components/template/select/template_select.h          | 2 +-
 esphome/components/template/sensor/template_sensor.h          | 2 +-
 esphome/components/template/switch/template_switch.h          | 2 +-
 esphome/components/template/text/template_text.h              | 2 +-
 .../components/template/text_sensor/template_text_sensor.h    | 2 +-
 esphome/components/template/valve/template_valve.h            | 2 +-
 18 files changed, 19 insertions(+), 19 deletions(-)

diff --git a/esphome/components/template/alarm_control_panel/template_alarm_control_panel.h b/esphome/components/template/alarm_control_panel/template_alarm_control_panel.h
index 40a79004da..202dc7c13f 100644
--- a/esphome/components/template/alarm_control_panel/template_alarm_control_panel.h
+++ b/esphome/components/template/alarm_control_panel/template_alarm_control_panel.h
@@ -49,7 +49,7 @@ struct SensorInfo {
   uint8_t store_index;
 };
 
-class TemplateAlarmControlPanel : public alarm_control_panel::AlarmControlPanel, public Component {
+class TemplateAlarmControlPanel final : public alarm_control_panel::AlarmControlPanel, public Component {
  public:
   TemplateAlarmControlPanel();
   void dump_config() override;
diff --git a/esphome/components/template/binary_sensor/template_binary_sensor.h b/esphome/components/template/binary_sensor/template_binary_sensor.h
index bc591391b9..0af709b097 100644
--- a/esphome/components/template/binary_sensor/template_binary_sensor.h
+++ b/esphome/components/template/binary_sensor/template_binary_sensor.h
@@ -7,7 +7,7 @@
 namespace esphome {
 namespace template_ {
 
-class TemplateBinarySensor : public Component, public binary_sensor::BinarySensor {
+class TemplateBinarySensor final : public Component, public binary_sensor::BinarySensor {
  public:
   template<typename F> void set_template(F &&f) { this->f_.set(std::forward<F>(f)); }
 
diff --git a/esphome/components/template/button/template_button.h b/esphome/components/template/button/template_button.h
index 68e976f64b..5bda82c58f 100644
--- a/esphome/components/template/button/template_button.h
+++ b/esphome/components/template/button/template_button.h
@@ -5,7 +5,7 @@
 namespace esphome {
 namespace template_ {
 
-class TemplateButton : public button::Button {
+class TemplateButton final : public button::Button {
  public:
   // Implements the abstract `press_action` but the `on_press` trigger already handles the press.
   void press_action() override{};
diff --git a/esphome/components/template/cover/template_cover.h b/esphome/components/template/cover/template_cover.h
index faff69f867..125c67bb86 100644
--- a/esphome/components/template/cover/template_cover.h
+++ b/esphome/components/template/cover/template_cover.h
@@ -14,7 +14,7 @@ enum TemplateCoverRestoreMode {
   COVER_RESTORE_AND_CALL,
 };
 
-class TemplateCover : public cover::Cover, public Component {
+class TemplateCover final : public cover::Cover, public Component {
  public:
   TemplateCover();
 
diff --git a/esphome/components/template/datetime/template_date.h b/esphome/components/template/datetime/template_date.h
index 7fed704d0e..fe64b0ba14 100644
--- a/esphome/components/template/datetime/template_date.h
+++ b/esphome/components/template/datetime/template_date.h
@@ -14,7 +14,7 @@
 namespace esphome {
 namespace template_ {
 
-class TemplateDate : public datetime::DateEntity, public PollingComponent {
+class TemplateDate final : public datetime::DateEntity, public PollingComponent {
  public:
   template<typename F> void set_template(F &&f) { this->f_.set(std::forward<F>(f)); }
 
diff --git a/esphome/components/template/datetime/template_datetime.h b/esphome/components/template/datetime/template_datetime.h
index ec45bf0326..c44bd85265 100644
--- a/esphome/components/template/datetime/template_datetime.h
+++ b/esphome/components/template/datetime/template_datetime.h
@@ -14,7 +14,7 @@
 namespace esphome {
 namespace template_ {
 
-class TemplateDateTime : public datetime::DateTimeEntity, public PollingComponent {
+class TemplateDateTime final : public datetime::DateTimeEntity, public PollingComponent {
  public:
   template<typename F> void set_template(F &&f) { this->f_.set(std::forward<F>(f)); }
 
diff --git a/esphome/components/template/datetime/template_time.h b/esphome/components/template/datetime/template_time.h
index ea7474c0ba..0c95330d27 100644
--- a/esphome/components/template/datetime/template_time.h
+++ b/esphome/components/template/datetime/template_time.h
@@ -14,7 +14,7 @@
 namespace esphome {
 namespace template_ {
 
-class TemplateTime : public datetime::TimeEntity, public PollingComponent {
+class TemplateTime final : public datetime::TimeEntity, public PollingComponent {
  public:
   template<typename F> void set_template(F &&f) { this->f_.set(std::forward<F>(f)); }
 
diff --git a/esphome/components/template/event/template_event.h b/esphome/components/template/event/template_event.h
index 251ae9299b..5467a64141 100644
--- a/esphome/components/template/event/template_event.h
+++ b/esphome/components/template/event/template_event.h
@@ -6,7 +6,7 @@
 namespace esphome {
 namespace template_ {
 
-class TemplateEvent : public Component, public event::Event {};
+class TemplateEvent final : public Component, public event::Event {};
 
 }  // namespace template_
 }  // namespace esphome
diff --git a/esphome/components/template/fan/template_fan.h b/esphome/components/template/fan/template_fan.h
index b09352f4d4..052b385b93 100644
--- a/esphome/components/template/fan/template_fan.h
+++ b/esphome/components/template/fan/template_fan.h
@@ -6,7 +6,7 @@
 namespace esphome {
 namespace template_ {
 
-class TemplateFan : public Component, public fan::Fan {
+class TemplateFan final : public Component, public fan::Fan {
  public:
   TemplateFan() {}
   void setup() override;
diff --git a/esphome/components/template/lock/template_lock.h b/esphome/components/template/lock/template_lock.h
index 14fca4635e..ac10794e4d 100644
--- a/esphome/components/template/lock/template_lock.h
+++ b/esphome/components/template/lock/template_lock.h
@@ -8,7 +8,7 @@
 namespace esphome {
 namespace template_ {
 
-class TemplateLock : public lock::Lock, public Component {
+class TemplateLock final : public lock::Lock, public Component {
  public:
   TemplateLock();
 
diff --git a/esphome/components/template/number/template_number.h b/esphome/components/template/number/template_number.h
index a9307e9246..876ec96b3b 100644
--- a/esphome/components/template/number/template_number.h
+++ b/esphome/components/template/number/template_number.h
@@ -9,7 +9,7 @@
 namespace esphome {
 namespace template_ {
 
-class TemplateNumber : public number::Number, public PollingComponent {
+class TemplateNumber final : public number::Number, public PollingComponent {
  public:
   template<typename F> void set_template(F &&f) { this->f_.set(std::forward<F>(f)); }
 
diff --git a/esphome/components/template/output/template_output.h b/esphome/components/template/output/template_output.h
index 90de801a5c..9ecfc446b9 100644
--- a/esphome/components/template/output/template_output.h
+++ b/esphome/components/template/output/template_output.h
@@ -7,7 +7,7 @@
 namespace esphome {
 namespace template_ {
 
-class TemplateBinaryOutput : public output::BinaryOutput {
+class TemplateBinaryOutput final : public output::BinaryOutput {
  public:
   Trigger<bool> *get_trigger() const { return trigger_; }
 
@@ -17,7 +17,7 @@ class TemplateBinaryOutput : public output::BinaryOutput {
   Trigger<bool> *trigger_ = new Trigger<bool>();
 };
 
-class TemplateFloatOutput : public output::FloatOutput {
+class TemplateFloatOutput final : public output::FloatOutput {
  public:
   Trigger<float> *get_trigger() const { return trigger_; }
 
diff --git a/esphome/components/template/select/template_select.h b/esphome/components/template/select/template_select.h
index 2dad059ade..cb5b546976 100644
--- a/esphome/components/template/select/template_select.h
+++ b/esphome/components/template/select/template_select.h
@@ -9,7 +9,7 @@
 namespace esphome {
 namespace template_ {
 
-class TemplateSelect : public select::Select, public PollingComponent {
+class TemplateSelect final : public select::Select, public PollingComponent {
  public:
   template<typename F> void set_template(F &&f) { this->f_.set(std::forward<F>(f)); }
 
diff --git a/esphome/components/template/sensor/template_sensor.h b/esphome/components/template/sensor/template_sensor.h
index 793d754a0f..3ca965dde3 100644
--- a/esphome/components/template/sensor/template_sensor.h
+++ b/esphome/components/template/sensor/template_sensor.h
@@ -7,7 +7,7 @@
 namespace esphome {
 namespace template_ {
 
-class TemplateSensor : public sensor::Sensor, public PollingComponent {
+class TemplateSensor final : public sensor::Sensor, public PollingComponent {
  public:
   template<typename F> void set_template(F &&f) { this->f_.set(std::forward<F>(f)); }
 
diff --git a/esphome/components/template/switch/template_switch.h b/esphome/components/template/switch/template_switch.h
index 18a374df35..35c18af448 100644
--- a/esphome/components/template/switch/template_switch.h
+++ b/esphome/components/template/switch/template_switch.h
@@ -8,7 +8,7 @@
 namespace esphome {
 namespace template_ {
 
-class TemplateSwitch : public switch_::Switch, public Component {
+class TemplateSwitch final : public switch_::Switch, public Component {
  public:
   TemplateSwitch();
 
diff --git a/esphome/components/template/text/template_text.h b/esphome/components/template/text/template_text.h
index c12021f80e..1a0a66ed5b 100644
--- a/esphome/components/template/text/template_text.h
+++ b/esphome/components/template/text/template_text.h
@@ -60,7 +60,7 @@ template<uint8_t SZ> class TextSaver : public TemplateTextSaverBase {
   }
 };
 
-class TemplateText : public text::Text, public PollingComponent {
+class TemplateText final : public text::Text, public PollingComponent {
  public:
   template<typename F> void set_template(F &&f) { this->f_.set(std::forward<F>(f)); }
 
diff --git a/esphome/components/template/text_sensor/template_text_sensor.h b/esphome/components/template/text_sensor/template_text_sensor.h
index 0d01c72023..da5c518c7f 100644
--- a/esphome/components/template/text_sensor/template_text_sensor.h
+++ b/esphome/components/template/text_sensor/template_text_sensor.h
@@ -8,7 +8,7 @@
 namespace esphome {
 namespace template_ {
 
-class TemplateTextSensor : public text_sensor::TextSensor, public PollingComponent {
+class TemplateTextSensor final : public text_sensor::TextSensor, public PollingComponent {
  public:
   template<typename F> void set_template(F &&f) { this->f_.set(std::forward<F>(f)); }
 
diff --git a/esphome/components/template/valve/template_valve.h b/esphome/components/template/valve/template_valve.h
index d6235f8e5c..c452648193 100644
--- a/esphome/components/template/valve/template_valve.h
+++ b/esphome/components/template/valve/template_valve.h
@@ -14,7 +14,7 @@ enum TemplateValveRestoreMode {
   VALVE_RESTORE_AND_CALL,
 };
 
-class TemplateValve : public valve::Valve, public Component {
+class TemplateValve final : public valve::Valve, public Component {
  public:
   TemplateValve();
 

From b08419fa473533e28a7cd86f98b2b3f98f1b7f27 Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@koston.org>
Date: Wed, 5 Nov 2025 12:30:45 -0600
Subject: [PATCH 3/8] [mqtt] Use StringRef to avoid string copies in discovery
 (#11731)

---
 .../mqtt/mqtt_alarm_control_panel.cpp         |  2 +-
 .../components/mqtt/mqtt_binary_sensor.cpp    |  9 ++++---
 esphome/components/mqtt/mqtt_button.cpp       |  7 ++---
 esphome/components/mqtt/mqtt_component.cpp    | 26 +++++++++++--------
 esphome/components/mqtt/mqtt_component.h      |  8 +++---
 esphome/components/mqtt/mqtt_cover.cpp        |  9 ++++---
 esphome/components/mqtt/mqtt_event.cpp        |  8 ++++--
 esphome/components/mqtt/mqtt_fan.cpp          | 14 +++++-----
 esphome/components/mqtt/mqtt_lock.cpp         |  2 +-
 esphome/components/mqtt/mqtt_number.cpp       | 14 +++++++---
 esphome/components/mqtt/mqtt_sensor.cpp       | 14 ++++++----
 esphome/components/mqtt/mqtt_switch.cpp       |  2 +-
 esphome/components/mqtt/mqtt_text_sensor.cpp  |  8 +++---
 esphome/components/mqtt/mqtt_update.cpp       |  2 +-
 esphome/components/mqtt/mqtt_valve.cpp        |  8 +++---
 15 files changed, 81 insertions(+), 52 deletions(-)

diff --git a/esphome/components/mqtt/mqtt_alarm_control_panel.cpp b/esphome/components/mqtt/mqtt_alarm_control_panel.cpp
index 94460c31a7..dd3df5f8aa 100644
--- a/esphome/components/mqtt/mqtt_alarm_control_panel.cpp
+++ b/esphome/components/mqtt/mqtt_alarm_control_panel.cpp
@@ -36,7 +36,7 @@ void MQTTAlarmControlPanelComponent::setup() {
     } else if (strcasecmp(payload.c_str(), "TRIGGERED") == 0) {
       call.triggered();
     } else {
-      ESP_LOGW(TAG, "'%s': Received unknown command payload %s", this->friendly_name().c_str(), payload.c_str());
+      ESP_LOGW(TAG, "'%s': Received unknown command payload %s", this->friendly_name_().c_str(), payload.c_str());
     }
     call.perform();
   });
diff --git a/esphome/components/mqtt/mqtt_binary_sensor.cpp b/esphome/components/mqtt/mqtt_binary_sensor.cpp
index 2ce4928574..479cee205a 100644
--- a/esphome/components/mqtt/mqtt_binary_sensor.cpp
+++ b/esphome/components/mqtt/mqtt_binary_sensor.cpp
@@ -30,9 +30,12 @@ MQTTBinarySensorComponent::MQTTBinarySensorComponent(binary_sensor::BinarySensor
 }
 
 void MQTTBinarySensorComponent::send_discovery(JsonObject root, mqtt::SendDiscoveryConfig &config) {
-  // NOLINTNEXTLINE(clang-analyzer-cplusplus.NewDeleteLeaks) false positive with ArduinoJson
-  if (!this->binary_sensor_->get_device_class().empty())
-    root[MQTT_DEVICE_CLASS] = this->binary_sensor_->get_device_class();
+  // NOLINTBEGIN(clang-analyzer-cplusplus.NewDeleteLeaks) false positive with ArduinoJson
+  const auto device_class = this->binary_sensor_->get_device_class_ref();
+  if (!device_class.empty()) {
+    root[MQTT_DEVICE_CLASS] = device_class;
+  }
+  // NOLINTEND(clang-analyzer-cplusplus.NewDeleteLeaks)
   if (this->binary_sensor_->is_status_binary_sensor())
     root[MQTT_PAYLOAD_ON] = mqtt::global_mqtt_client->get_availability().payload_available;
   if (this->binary_sensor_->is_status_binary_sensor())
diff --git a/esphome/components/mqtt/mqtt_button.cpp b/esphome/components/mqtt/mqtt_button.cpp
index b3435edf38..f8eb0eab2d 100644
--- a/esphome/components/mqtt/mqtt_button.cpp
+++ b/esphome/components/mqtt/mqtt_button.cpp
@@ -20,7 +20,7 @@ void MQTTButtonComponent::setup() {
     if (payload == "PRESS") {
       this->button_->press();
     } else {
-      ESP_LOGW(TAG, "'%s': Received unknown status payload: %s", this->friendly_name().c_str(), payload.c_str());
+      ESP_LOGW(TAG, "'%s': Received unknown status payload: %s", this->friendly_name_().c_str(), payload.c_str());
       this->status_momentary_warning("state", 5000);
     }
   });
@@ -33,8 +33,9 @@ void MQTTButtonComponent::dump_config() {
 void MQTTButtonComponent::send_discovery(JsonObject root, mqtt::SendDiscoveryConfig &config) {
   // NOLINTBEGIN(clang-analyzer-cplusplus.NewDeleteLeaks) false positive with ArduinoJson
   config.state_topic = false;
-  if (!this->button_->get_device_class().empty()) {
-    root[MQTT_DEVICE_CLASS] = this->button_->get_device_class();
+  const auto device_class = this->button_->get_device_class_ref();
+  if (!device_class.empty()) {
+    root[MQTT_DEVICE_CLASS] = device_class;
   }
   // NOLINTEND(clang-analyzer-cplusplus.NewDeleteLeaks)
 }
diff --git a/esphome/components/mqtt/mqtt_component.cpp b/esphome/components/mqtt/mqtt_component.cpp
index eb6114008a..1cd818964e 100644
--- a/esphome/components/mqtt/mqtt_component.cpp
+++ b/esphome/components/mqtt/mqtt_component.cpp
@@ -64,11 +64,11 @@ bool MQTTComponent::send_discovery_() {
   const MQTTDiscoveryInfo &discovery_info = global_mqtt_client->get_discovery_info();
 
   if (discovery_info.clean) {
-    ESP_LOGV(TAG, "'%s': Cleaning discovery", this->friendly_name().c_str());
+    ESP_LOGV(TAG, "'%s': Cleaning discovery", this->friendly_name_().c_str());
     return global_mqtt_client->publish(this->get_discovery_topic_(discovery_info), "", 0, this->qos_, true);
   }
 
-  ESP_LOGV(TAG, "'%s': Sending discovery", this->friendly_name().c_str());
+  ESP_LOGV(TAG, "'%s': Sending discovery", this->friendly_name_().c_str());
 
   // NOLINTBEGIN(clang-analyzer-cplusplus.NewDeleteLeaks) false positive with ArduinoJson
   return global_mqtt_client->publish_json(
@@ -85,12 +85,16 @@ bool MQTTComponent::send_discovery_() {
         }
 
         // Fields from EntityBase
-        root[MQTT_NAME] = this->get_entity()->has_own_name() ? this->friendly_name() : "";
+        root[MQTT_NAME] = this->get_entity()->has_own_name() ? this->friendly_name_() : "";
 
-        if (this->is_disabled_by_default())
+        if (this->is_disabled_by_default_())
           root[MQTT_ENABLED_BY_DEFAULT] = false;
-        if (!this->get_icon().empty())
-          root[MQTT_ICON] = this->get_icon();
+        // NOLINTBEGIN(clang-analyzer-cplusplus.NewDeleteLeaks) false positive with ArduinoJson
+        const auto icon_ref = this->get_icon_ref_();
+        if (!icon_ref.empty()) {
+          root[MQTT_ICON] = icon_ref;
+        }
+        // NOLINTEND(clang-analyzer-cplusplus.NewDeleteLeaks)
 
         const auto entity_category = this->get_entity()->get_entity_category();
         switch (entity_category) {
@@ -122,7 +126,7 @@ bool MQTTComponent::send_discovery_() {
         const MQTTDiscoveryInfo &discovery_info = global_mqtt_client->get_discovery_info();
         if (discovery_info.unique_id_generator == MQTT_MAC_ADDRESS_UNIQUE_ID_GENERATOR) {
           char friendly_name_hash[9];
-          sprintf(friendly_name_hash, "%08" PRIx32, fnv1_hash(this->friendly_name()));
+          sprintf(friendly_name_hash, "%08" PRIx32, fnv1_hash(this->friendly_name_()));
           friendly_name_hash[8] = 0;  // ensure the hash-string ends with null
           root[MQTT_UNIQUE_ID] = get_mac_address() + "-" + this->component_type() + "-" + friendly_name_hash;
         } else {
@@ -184,7 +188,7 @@ bool MQTTComponent::is_discovery_enabled() const {
 }
 
 std::string MQTTComponent::get_default_object_id_() const {
-  return str_sanitize(str_snake_case(this->friendly_name()));
+  return str_sanitize(str_snake_case(this->friendly_name_()));
 }
 
 void MQTTComponent::subscribe(const std::string &topic, mqtt_callback_t callback, uint8_t qos) {
@@ -268,9 +272,9 @@ void MQTTComponent::schedule_resend_state() { this->resend_state_ = true; }
 bool MQTTComponent::is_connected_() const { return global_mqtt_client->is_connected(); }
 
 // Pull these properties from EntityBase if not overridden
-std::string MQTTComponent::friendly_name() const { return this->get_entity()->get_name(); }
-std::string MQTTComponent::get_icon() const { return this->get_entity()->get_icon(); }
-bool MQTTComponent::is_disabled_by_default() const { return this->get_entity()->is_disabled_by_default(); }
+std::string MQTTComponent::friendly_name_() const { return this->get_entity()->get_name(); }
+StringRef MQTTComponent::get_icon_ref_() const { return this->get_entity()->get_icon_ref(); }
+bool MQTTComponent::is_disabled_by_default_() const { return this->get_entity()->is_disabled_by_default(); }
 bool MQTTComponent::is_internal() {
   if (this->has_custom_state_topic_) {
     // If the custom state_topic is null, return true as it is internal and should not publish
diff --git a/esphome/components/mqtt/mqtt_component.h b/esphome/components/mqtt/mqtt_component.h
index 851fdd842c..2f8dfcf64e 100644
--- a/esphome/components/mqtt/mqtt_component.h
+++ b/esphome/components/mqtt/mqtt_component.h
@@ -165,13 +165,13 @@ class MQTTComponent : public Component {
   virtual const EntityBase *get_entity() const = 0;
 
   /// Get the friendly name of this MQTT component.
-  virtual std::string friendly_name() const;
+  std::string friendly_name_() const;
 
-  /// Get the icon field of this component
-  virtual std::string get_icon() const;
+  /// Get the icon field of this component as StringRef
+  StringRef get_icon_ref_() const;
 
   /// Get whether the underlying Entity is disabled by default
-  virtual bool is_disabled_by_default() const;
+  bool is_disabled_by_default_() const;
 
   /// Get the MQTT topic that new states will be shared to.
   std::string get_state_topic_() const;
diff --git a/esphome/components/mqtt/mqtt_cover.cpp b/esphome/components/mqtt/mqtt_cover.cpp
index 6fb61ee469..b63aa66d29 100644
--- a/esphome/components/mqtt/mqtt_cover.cpp
+++ b/esphome/components/mqtt/mqtt_cover.cpp
@@ -67,9 +67,12 @@ void MQTTCoverComponent::dump_config() {
   }
 }
 void MQTTCoverComponent::send_discovery(JsonObject root, mqtt::SendDiscoveryConfig &config) {
-  // NOLINTNEXTLINE(clang-analyzer-cplusplus.NewDeleteLeaks) false positive with ArduinoJson
-  if (!this->cover_->get_device_class().empty())
-    root[MQTT_DEVICE_CLASS] = this->cover_->get_device_class();
+  // NOLINTBEGIN(clang-analyzer-cplusplus.NewDeleteLeaks) false positive with ArduinoJson
+  const auto device_class = this->cover_->get_device_class_ref();
+  if (!device_class.empty()) {
+    root[MQTT_DEVICE_CLASS] = device_class;
+  }
+  // NOLINTEND(clang-analyzer-cplusplus.NewDeleteLeaks)
 
   auto traits = this->cover_->get_traits();
   if (traits.get_is_assumed_state()) {
diff --git a/esphome/components/mqtt/mqtt_event.cpp b/esphome/components/mqtt/mqtt_event.cpp
index f972d545c6..e206335446 100644
--- a/esphome/components/mqtt/mqtt_event.cpp
+++ b/esphome/components/mqtt/mqtt_event.cpp
@@ -21,8 +21,12 @@ void MQTTEventComponent::send_discovery(JsonObject root, mqtt::SendDiscoveryConf
   for (const auto &event_type : this->event_->get_event_types())
     event_types.add(event_type);
 
-  if (!this->event_->get_device_class().empty())
-    root[MQTT_DEVICE_CLASS] = this->event_->get_device_class();
+  // NOLINTBEGIN(clang-analyzer-cplusplus.NewDeleteLeaks) false positive with ArduinoJson
+  const auto device_class = this->event_->get_device_class_ref();
+  if (!device_class.empty()) {
+    root[MQTT_DEVICE_CLASS] = device_class;
+  }
+  // NOLINTEND(clang-analyzer-cplusplus.NewDeleteLeaks)
 
   config.command_topic = false;
 }
diff --git a/esphome/components/mqtt/mqtt_fan.cpp b/esphome/components/mqtt/mqtt_fan.cpp
index 70e1ae3b4a..2aefc3a4db 100644
--- a/esphome/components/mqtt/mqtt_fan.cpp
+++ b/esphome/components/mqtt/mqtt_fan.cpp
@@ -24,15 +24,15 @@ void MQTTFanComponent::setup() {
     auto val = parse_on_off(payload.c_str());
     switch (val) {
       case PARSE_ON:
-        ESP_LOGD(TAG, "'%s' Turning Fan ON.", this->friendly_name().c_str());
+        ESP_LOGD(TAG, "'%s' Turning Fan ON.", this->friendly_name_().c_str());
         this->state_->turn_on().perform();
         break;
       case PARSE_OFF:
-        ESP_LOGD(TAG, "'%s' Turning Fan OFF.", this->friendly_name().c_str());
+        ESP_LOGD(TAG, "'%s' Turning Fan OFF.", this->friendly_name_().c_str());
         this->state_->turn_off().perform();
         break;
       case PARSE_TOGGLE:
-        ESP_LOGD(TAG, "'%s' Toggling Fan.", this->friendly_name().c_str());
+        ESP_LOGD(TAG, "'%s' Toggling Fan.", this->friendly_name_().c_str());
         this->state_->toggle().perform();
         break;
       case PARSE_NONE:
@@ -48,11 +48,11 @@ void MQTTFanComponent::setup() {
       auto val = parse_on_off(payload.c_str(), "forward", "reverse");
       switch (val) {
         case PARSE_ON:
-          ESP_LOGD(TAG, "'%s': Setting direction FORWARD", this->friendly_name().c_str());
+          ESP_LOGD(TAG, "'%s': Setting direction FORWARD", this->friendly_name_().c_str());
           this->state_->make_call().set_direction(fan::FanDirection::FORWARD).perform();
           break;
         case PARSE_OFF:
-          ESP_LOGD(TAG, "'%s': Setting direction REVERSE", this->friendly_name().c_str());
+          ESP_LOGD(TAG, "'%s': Setting direction REVERSE", this->friendly_name_().c_str());
           this->state_->make_call().set_direction(fan::FanDirection::REVERSE).perform();
           break;
         case PARSE_TOGGLE:
@@ -75,11 +75,11 @@ void MQTTFanComponent::setup() {
                       auto val = parse_on_off(payload.c_str(), "oscillate_on", "oscillate_off");
                       switch (val) {
                         case PARSE_ON:
-                          ESP_LOGD(TAG, "'%s': Setting oscillating ON", this->friendly_name().c_str());
+                          ESP_LOGD(TAG, "'%s': Setting oscillating ON", this->friendly_name_().c_str());
                           this->state_->make_call().set_oscillating(true).perform();
                           break;
                         case PARSE_OFF:
-                          ESP_LOGD(TAG, "'%s': Setting oscillating OFF", this->friendly_name().c_str());
+                          ESP_LOGD(TAG, "'%s': Setting oscillating OFF", this->friendly_name_().c_str());
                           this->state_->make_call().set_oscillating(false).perform();
                           break;
                         case PARSE_TOGGLE:
diff --git a/esphome/components/mqtt/mqtt_lock.cpp b/esphome/components/mqtt/mqtt_lock.cpp
index 0412624983..0e15377ba4 100644
--- a/esphome/components/mqtt/mqtt_lock.cpp
+++ b/esphome/components/mqtt/mqtt_lock.cpp
@@ -24,7 +24,7 @@ void MQTTLockComponent::setup() {
     } else if (strcasecmp(payload.c_str(), "OPEN") == 0) {
       this->lock_->open();
     } else {
-      ESP_LOGW(TAG, "'%s': Received unknown status payload: %s", this->friendly_name().c_str(), payload.c_str());
+      ESP_LOGW(TAG, "'%s': Received unknown status payload: %s", this->friendly_name_().c_str(), payload.c_str());
       this->status_momentary_warning("state", 5000);
     }
   });
diff --git a/esphome/components/mqtt/mqtt_number.cpp b/esphome/components/mqtt/mqtt_number.cpp
index a44632ff30..f419eac130 100644
--- a/esphome/components/mqtt/mqtt_number.cpp
+++ b/esphome/components/mqtt/mqtt_number.cpp
@@ -44,8 +44,11 @@ void MQTTNumberComponent::send_discovery(JsonObject root, mqtt::SendDiscoveryCon
   root[MQTT_MIN] = traits.get_min_value();
   root[MQTT_MAX] = traits.get_max_value();
   root[MQTT_STEP] = traits.get_step();
-  if (!this->number_->traits.get_unit_of_measurement().empty())
-    root[MQTT_UNIT_OF_MEASUREMENT] = this->number_->traits.get_unit_of_measurement();
+  // NOLINTBEGIN(clang-analyzer-cplusplus.NewDeleteLeaks) false positive with ArduinoJson
+  const auto unit_of_measurement = this->number_->traits.get_unit_of_measurement_ref();
+  if (!unit_of_measurement.empty()) {
+    root[MQTT_UNIT_OF_MEASUREMENT] = unit_of_measurement;
+  }
   switch (this->number_->traits.get_mode()) {
     case NUMBER_MODE_AUTO:
       break;
@@ -56,8 +59,11 @@ void MQTTNumberComponent::send_discovery(JsonObject root, mqtt::SendDiscoveryCon
       root[MQTT_MODE] = "slider";
       break;
   }
-  if (!this->number_->traits.get_device_class().empty())
-    root[MQTT_DEVICE_CLASS] = this->number_->traits.get_device_class();
+  const auto device_class = this->number_->traits.get_device_class_ref();
+  if (!device_class.empty()) {
+    root[MQTT_DEVICE_CLASS] = device_class;
+  }
+  // NOLINTEND(clang-analyzer-cplusplus.NewDeleteLeaks)
 
   config.command_topic = true;
 }
diff --git a/esphome/components/mqtt/mqtt_sensor.cpp b/esphome/components/mqtt/mqtt_sensor.cpp
index 9e61f6ef3b..010ac3013e 100644
--- a/esphome/components/mqtt/mqtt_sensor.cpp
+++ b/esphome/components/mqtt/mqtt_sensor.cpp
@@ -44,13 +44,17 @@ void MQTTSensorComponent::set_expire_after(uint32_t expire_after) { this->expire
 void MQTTSensorComponent::disable_expire_after() { this->expire_after_ = 0; }
 
 void MQTTSensorComponent::send_discovery(JsonObject root, mqtt::SendDiscoveryConfig &config) {
-  // NOLINTNEXTLINE(clang-analyzer-cplusplus.NewDeleteLeaks) false positive with ArduinoJson
-  if (!this->sensor_->get_device_class().empty()) {
-    root[MQTT_DEVICE_CLASS] = this->sensor_->get_device_class();
+  // NOLINTBEGIN(clang-analyzer-cplusplus.NewDeleteLeaks) false positive with ArduinoJson
+  const auto device_class = this->sensor_->get_device_class_ref();
+  if (!device_class.empty()) {
+    root[MQTT_DEVICE_CLASS] = device_class;
   }
 
-  if (!this->sensor_->get_unit_of_measurement().empty())
-    root[MQTT_UNIT_OF_MEASUREMENT] = this->sensor_->get_unit_of_measurement();
+  const auto unit_of_measurement = this->sensor_->get_unit_of_measurement_ref();
+  if (!unit_of_measurement.empty()) {
+    root[MQTT_UNIT_OF_MEASUREMENT] = unit_of_measurement;
+  }
+  // NOLINTEND(clang-analyzer-cplusplus.NewDeleteLeaks)
 
   if (this->get_expire_after() > 0)
     root[MQTT_EXPIRE_AFTER] = this->get_expire_after() / 1000;
diff --git a/esphome/components/mqtt/mqtt_switch.cpp b/esphome/components/mqtt/mqtt_switch.cpp
index 8b1323bdb2..b3a35420b9 100644
--- a/esphome/components/mqtt/mqtt_switch.cpp
+++ b/esphome/components/mqtt/mqtt_switch.cpp
@@ -29,7 +29,7 @@ void MQTTSwitchComponent::setup() {
         break;
       case PARSE_NONE:
       default:
-        ESP_LOGW(TAG, "'%s': Received unknown status payload: %s", this->friendly_name().c_str(), payload.c_str());
+        ESP_LOGW(TAG, "'%s': Received unknown status payload: %s", this->friendly_name_().c_str(), payload.c_str());
         this->status_momentary_warning("state", 5000);
         break;
     }
diff --git a/esphome/components/mqtt/mqtt_text_sensor.cpp b/esphome/components/mqtt/mqtt_text_sensor.cpp
index 42260ed2a8..e6e7cf04e8 100644
--- a/esphome/components/mqtt/mqtt_text_sensor.cpp
+++ b/esphome/components/mqtt/mqtt_text_sensor.cpp
@@ -15,10 +15,12 @@ using namespace esphome::text_sensor;
 
 MQTTTextSensor::MQTTTextSensor(TextSensor *sensor) : sensor_(sensor) {}
 void MQTTTextSensor::send_discovery(JsonObject root, mqtt::SendDiscoveryConfig &config) {
-  // NOLINTNEXTLINE(clang-analyzer-cplusplus.NewDeleteLeaks) false positive with ArduinoJson
-  if (!this->sensor_->get_device_class().empty()) {
-    root[MQTT_DEVICE_CLASS] = this->sensor_->get_device_class();
+  // NOLINTBEGIN(clang-analyzer-cplusplus.NewDeleteLeaks) false positive with ArduinoJson
+  const auto device_class = this->sensor_->get_device_class_ref();
+  if (!device_class.empty()) {
+    root[MQTT_DEVICE_CLASS] = device_class;
   }
+  // NOLINTEND(clang-analyzer-cplusplus.NewDeleteLeaks)
   config.command_topic = false;
 }
 void MQTTTextSensor::setup() {
diff --git a/esphome/components/mqtt/mqtt_update.cpp b/esphome/components/mqtt/mqtt_update.cpp
index 5d4807c7f3..20f3a69a9e 100644
--- a/esphome/components/mqtt/mqtt_update.cpp
+++ b/esphome/components/mqtt/mqtt_update.cpp
@@ -20,7 +20,7 @@ void MQTTUpdateComponent::setup() {
     if (payload == "INSTALL") {
       this->update_->perform();
     } else {
-      ESP_LOGW(TAG, "'%s': Received unknown update payload: %s", this->friendly_name().c_str(), payload.c_str());
+      ESP_LOGW(TAG, "'%s': Received unknown update payload: %s", this->friendly_name_().c_str(), payload.c_str());
       this->status_momentary_warning("state", 5000);
     }
   });
diff --git a/esphome/components/mqtt/mqtt_valve.cpp b/esphome/components/mqtt/mqtt_valve.cpp
index 551398cf42..ae60670748 100644
--- a/esphome/components/mqtt/mqtt_valve.cpp
+++ b/esphome/components/mqtt/mqtt_valve.cpp
@@ -49,10 +49,12 @@ void MQTTValveComponent::dump_config() {
   }
 }
 void MQTTValveComponent::send_discovery(JsonObject root, mqtt::SendDiscoveryConfig &config) {
-  // NOLINTNEXTLINE(clang-analyzer-cplusplus.NewDeleteLeaks) false positive with ArduinoJson
-  if (!this->valve_->get_device_class().empty()) {
-    root[MQTT_DEVICE_CLASS] = this->valve_->get_device_class();
+  // NOLINTBEGIN(clang-analyzer-cplusplus.NewDeleteLeaks) false positive with ArduinoJson
+  const auto device_class = this->valve_->get_device_class_ref();
+  if (!device_class.empty()) {
+    root[MQTT_DEVICE_CLASS] = device_class;
   }
+  // NOLINTEND(clang-analyzer-cplusplus.NewDeleteLeaks)
 
   auto traits = this->valve_->get_traits();
   if (traits.get_is_assumed_state()) {

From be006ecaddad5df7c2be5cfa3ffa2499dda5c203 Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@koston.org>
Date: Wed, 5 Nov 2025 12:31:19 -0600
Subject: [PATCH 4/8] [mdns] Eliminate redundant hostname copy to save heap
 memory (#11734)

---
 esphome/components/mdns/mdns_component.cpp | 4 +---
 esphome/components/mdns/mdns_component.h   | 1 -
 esphome/components/mdns/mdns_esp32.cpp     | 6 ++++--
 esphome/components/mdns/mdns_esp8266.cpp   | 3 ++-
 esphome/components/mdns/mdns_libretiny.cpp | 3 ++-
 esphome/components/mdns/mdns_rp2040.cpp    | 3 ++-
 6 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/esphome/components/mdns/mdns_component.cpp b/esphome/components/mdns/mdns_component.cpp
index d476136554..2c3150ff5d 100644
--- a/esphome/components/mdns/mdns_component.cpp
+++ b/esphome/components/mdns/mdns_component.cpp
@@ -37,8 +37,6 @@ MDNS_STATIC_CONST_CHAR(SERVICE_TCP, "_tcp");
 MDNS_STATIC_CONST_CHAR(VALUE_VERSION, ESPHOME_VERSION);
 
 void MDNSComponent::compile_records_(StaticVector<MDNSService, MDNS_SERVICE_COUNT> &services) {
-  this->hostname_ = App.get_name();
-
   // IMPORTANT: The #ifdef blocks below must match COMPONENTS_WITH_MDNS_SERVICES
   // in mdns/__init__.py. If you add a new service here, update both locations.
 
@@ -179,7 +177,7 @@ void MDNSComponent::dump_config() {
   ESP_LOGCONFIG(TAG,
                 "mDNS:\n"
                 "  Hostname: %s",
-                this->hostname_.c_str());
+                App.get_name().c_str());
 #ifdef USE_MDNS_STORE_SERVICES
   ESP_LOGV(TAG, "  Services:");
   for (const auto &service : this->services_) {
diff --git a/esphome/components/mdns/mdns_component.h b/esphome/components/mdns/mdns_component.h
index 35371fd739..f4237d5a69 100644
--- a/esphome/components/mdns/mdns_component.h
+++ b/esphome/components/mdns/mdns_component.h
@@ -76,7 +76,6 @@ class MDNSComponent : public Component {
 #ifdef USE_MDNS_STORE_SERVICES
   StaticVector<MDNSService, MDNS_SERVICE_COUNT> services_{};
 #endif
-  std::string hostname_;
   void compile_records_(StaticVector<MDNSService, MDNS_SERVICE_COUNT> &services);
 };
 
diff --git a/esphome/components/mdns/mdns_esp32.cpp b/esphome/components/mdns/mdns_esp32.cpp
index c02bfcbadb..ecdc926cc9 100644
--- a/esphome/components/mdns/mdns_esp32.cpp
+++ b/esphome/components/mdns/mdns_esp32.cpp
@@ -2,6 +2,7 @@
 #if defined(USE_ESP32) && defined(USE_MDNS)
 
 #include <mdns.h>
+#include "esphome/core/application.h"
 #include "esphome/core/hal.h"
 #include "esphome/core/log.h"
 #include "mdns_component.h"
@@ -27,8 +28,9 @@ void MDNSComponent::setup() {
     return;
   }
 
-  mdns_hostname_set(this->hostname_.c_str());
-  mdns_instance_name_set(this->hostname_.c_str());
+  const char *hostname = App.get_name().c_str();
+  mdns_hostname_set(hostname);
+  mdns_instance_name_set(hostname);
 
   for (const auto &service : services) {
     auto txt_records = std::make_unique<mdns_txt_item_t[]>(service.txt_records.size());
diff --git a/esphome/components/mdns/mdns_esp8266.cpp b/esphome/components/mdns/mdns_esp8266.cpp
index 25a3defa7b..9bbb406070 100644
--- a/esphome/components/mdns/mdns_esp8266.cpp
+++ b/esphome/components/mdns/mdns_esp8266.cpp
@@ -4,6 +4,7 @@
 #include <ESP8266mDNS.h>
 #include "esphome/components/network/ip_address.h"
 #include "esphome/components/network/util.h"
+#include "esphome/core/application.h"
 #include "esphome/core/hal.h"
 #include "esphome/core/log.h"
 #include "mdns_component.h"
@@ -20,7 +21,7 @@ void MDNSComponent::setup() {
   this->compile_records_(services);
 #endif
 
-  MDNS.begin(this->hostname_.c_str());
+  MDNS.begin(App.get_name().c_str());
 
   for (const auto &service : services) {
     // Strip the leading underscore from the proto and service_type. While it is
diff --git a/esphome/components/mdns/mdns_libretiny.cpp b/esphome/components/mdns/mdns_libretiny.cpp
index a3e317a2bf..fb2088f719 100644
--- a/esphome/components/mdns/mdns_libretiny.cpp
+++ b/esphome/components/mdns/mdns_libretiny.cpp
@@ -3,6 +3,7 @@
 
 #include "esphome/components/network/ip_address.h"
 #include "esphome/components/network/util.h"
+#include "esphome/core/application.h"
 #include "esphome/core/log.h"
 #include "mdns_component.h"
 
@@ -20,7 +21,7 @@ void MDNSComponent::setup() {
   this->compile_records_(services);
 #endif
 
-  MDNS.begin(this->hostname_.c_str());
+  MDNS.begin(App.get_name().c_str());
 
   for (const auto &service : services) {
     // Strip the leading underscore from the proto and service_type. While it is
diff --git a/esphome/components/mdns/mdns_rp2040.cpp b/esphome/components/mdns/mdns_rp2040.cpp
index 791fa3934d..a9f5349f14 100644
--- a/esphome/components/mdns/mdns_rp2040.cpp
+++ b/esphome/components/mdns/mdns_rp2040.cpp
@@ -3,6 +3,7 @@
 
 #include "esphome/components/network/ip_address.h"
 #include "esphome/components/network/util.h"
+#include "esphome/core/application.h"
 #include "esphome/core/log.h"
 #include "mdns_component.h"
 
@@ -20,7 +21,7 @@ void MDNSComponent::setup() {
   this->compile_records_(services);
 #endif
 
-  MDNS.begin(this->hostname_.c_str());
+  MDNS.begin(App.get_name().c_str());
 
   for (const auto &service : services) {
     // Strip the leading underscore from the proto and service_type. While it is

From 00c0854323a79663a27243f05db911be9ad956e1 Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@koston.org>
Date: Wed, 5 Nov 2025 12:50:35 -0600
Subject: [PATCH 5/8] [core] Deprecate get_icon(), get_device_class(),
 get_unit_of_measurement() and fix remaining non-MQTT usages (#11732)

---
 esphome/components/graph/graph.cpp                   |  4 ++--
 esphome/components/prometheus/prometheus_handler.cpp |  2 +-
 esphome/components/sprinkler/sprinkler.cpp           |  4 ++--
 esphome/core/entity_base.h                           | 12 +++++++++---
 4 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/esphome/components/graph/graph.cpp b/esphome/components/graph/graph.cpp
index ac6ace96ee..88bb306408 100644
--- a/esphome/components/graph/graph.cpp
+++ b/esphome/components/graph/graph.cpp
@@ -235,7 +235,7 @@ void GraphLegend::init(Graph *g) {
       std::string valstr =
           value_accuracy_to_string(trace->sensor_->get_state(), trace->sensor_->get_accuracy_decimals());
       if (this->units_) {
-        valstr += trace->sensor_->get_unit_of_measurement();
+        valstr += trace->sensor_->get_unit_of_measurement_ref();
       }
       this->font_value_->measure(valstr.c_str(), &fw, &fos, &fbl, &fh);
       if (fw > valw)
@@ -371,7 +371,7 @@ void Graph::draw_legend(display::Display *buff, uint16_t x_offset, uint16_t y_of
       std::string valstr =
           value_accuracy_to_string(trace->sensor_->get_state(), trace->sensor_->get_accuracy_decimals());
       if (legend_->units_) {
-        valstr += trace->sensor_->get_unit_of_measurement();
+        valstr += trace->sensor_->get_unit_of_measurement_ref();
       }
       buff->printf(xv, yv, legend_->font_value_, trace->get_line_color(), TextAlign::TOP_CENTER, "%s", valstr.c_str());
       ESP_LOGV(TAG, "    value: %s", valstr.c_str());
diff --git a/esphome/components/prometheus/prometheus_handler.cpp b/esphome/components/prometheus/prometheus_handler.cpp
index 6e7ed6f79f..5cfcacf0cb 100644
--- a/esphome/components/prometheus/prometheus_handler.cpp
+++ b/esphome/components/prometheus/prometheus_handler.cpp
@@ -158,7 +158,7 @@ void PrometheusHandler::sensor_row_(AsyncResponseStream *stream, sensor::Sensor
     stream->print(ESPHOME_F("\",name=\""));
     stream->print(relabel_name_(obj).c_str());
     stream->print(ESPHOME_F("\",unit=\""));
-    stream->print(obj->get_unit_of_measurement().c_str());
+    stream->print(obj->get_unit_of_measurement_ref().c_str());
     stream->print(ESPHOME_F("\"} "));
     stream->print(value_accuracy_to_string(obj->state, obj->get_accuracy_decimals()).c_str());
     stream->print(ESPHOME_F("\n"));
diff --git a/esphome/components/sprinkler/sprinkler.cpp b/esphome/components/sprinkler/sprinkler.cpp
index 7676e17468..8edb240a41 100644
--- a/esphome/components/sprinkler/sprinkler.cpp
+++ b/esphome/components/sprinkler/sprinkler.cpp
@@ -650,7 +650,7 @@ void Sprinkler::set_valve_run_duration(const optional<size_t> valve_number, cons
     return;
   }
   auto call = this->valve_[valve_number.value()].run_duration_number->make_call();
-  if (this->valve_[valve_number.value()].run_duration_number->traits.get_unit_of_measurement() == MIN_STR) {
+  if (this->valve_[valve_number.value()].run_duration_number->traits.get_unit_of_measurement_ref() == MIN_STR) {
     call.set_value(run_duration.value() / 60.0);
   } else {
     call.set_value(run_duration.value());
@@ -732,7 +732,7 @@ uint32_t Sprinkler::valve_run_duration(const size_t valve_number) {
     return 0;
   }
   if (this->valve_[valve_number].run_duration_number != nullptr) {
-    if (this->valve_[valve_number].run_duration_number->traits.get_unit_of_measurement() == MIN_STR) {
+    if (this->valve_[valve_number].run_duration_number->traits.get_unit_of_measurement_ref() == MIN_STR) {
       return static_cast<uint32_t>(roundf(this->valve_[valve_number].run_duration_number->state * 60));
     } else {
       return static_cast<uint32_t>(roundf(this->valve_[valve_number].run_duration_number->state));
diff --git a/esphome/core/entity_base.h b/esphome/core/entity_base.h
index 80cd6b8e77..6e5362464f 100644
--- a/esphome/core/entity_base.h
+++ b/esphome/core/entity_base.h
@@ -61,7 +61,9 @@ class EntityBase {
   }
 
   // Get/set this entity's icon
-  std::string get_icon() const;
+  [[deprecated("Use get_icon_ref() instead for better performance (avoids string copy). Will stop working in ESPHome "
+               "2026.5.0")]] std::string
+  get_icon() const;
   void set_icon(const char *icon);
   StringRef get_icon_ref() const {
     static constexpr auto EMPTY_STRING = StringRef::from_lit("");
@@ -158,7 +160,9 @@ class EntityBase {
 class EntityBase_DeviceClass {  // NOLINT(readability-identifier-naming)
  public:
   /// Get the device class, using the manual override if set.
-  std::string get_device_class();
+  [[deprecated("Use get_device_class_ref() instead for better performance (avoids string copy). Will stop working in "
+               "ESPHome 2026.5.0")]] std::string
+  get_device_class();
   /// Manually set the device class.
   void set_device_class(const char *device_class);
   /// Get the device class as StringRef
@@ -174,7 +178,9 @@ class EntityBase_DeviceClass {  // NOLINT(readability-identifier-naming)
 class EntityBase_UnitOfMeasurement {  // NOLINT(readability-identifier-naming)
  public:
   /// Get the unit of measurement, using the manual override if set.
-  std::string get_unit_of_measurement();
+  [[deprecated("Use get_unit_of_measurement_ref() instead for better performance (avoids string copy). Will stop "
+               "working in ESPHome 2026.5.0")]] std::string
+  get_unit_of_measurement();
   /// Manually set the unit of measurement.
   void set_unit_of_measurement(const char *unit_of_measurement);
   /// Get the unit of measurement as StringRef

From aa5795c019c055e08807f9943633d3a8582582e4 Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@koston.org>
Date: Wed, 5 Nov 2025 13:17:34 -0600
Subject: [PATCH 6/8] [tests] Fix ID collision between bl0940 and nau7802
 component tests (#11739)

---
 tests/components/bl0940/common.yaml  | 6 +++---
 tests/components/nau7802/common.yaml | 8 ++++----
 2 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/tests/components/bl0940/common.yaml b/tests/components/bl0940/common.yaml
index 0b73fd6d55..e476ba10c0 100644
--- a/tests/components/bl0940/common.yaml
+++ b/tests/components/bl0940/common.yaml
@@ -1,11 +1,11 @@
 button:
   - platform: bl0940
-    bl0940_id: test_id
+    bl0940_id: bl0940_test_id
     name: Cal Reset
 
 sensor:
   - platform: bl0940
-    id: test_id
+    id: bl0940_test_id
     voltage:
       name: BL0940 Voltage
     current:
@@ -22,7 +22,7 @@ sensor:
 number:
   - platform: bl0940
     id: bl0940_number_id
-    bl0940_id: test_id
+    bl0940_id: bl0940_test_id
     current_calibration:
       name: Cal Current
       min_value: -5
diff --git a/tests/components/nau7802/common.yaml b/tests/components/nau7802/common.yaml
index 5c52c33dad..5251910df9 100644
--- a/tests/components/nau7802/common.yaml
+++ b/tests/components/nau7802/common.yaml
@@ -1,13 +1,13 @@
 sensor:
   - platform: nau7802
     i2c_id: i2c_bus
-    id: test_id
+    id: nau7802_test_id
     name: weight
     gain: 32
     ldo_voltage: "3.0v"
     samples_per_second: 10
     on_value:
       then:
-        - nau7802.calibrate_external_offset: test_id
-        - nau7802.calibrate_internal_offset: test_id
-        - nau7802.calibrate_gain: test_id
+        - nau7802.calibrate_external_offset: nau7802_test_id
+        - nau7802.calibrate_internal_offset: nau7802_test_id
+        - nau7802.calibrate_gain: nau7802_test_id

From ce5e6088638d6b5cdc2becc34196205d3e03b2dc Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@koston.org>
Date: Wed, 5 Nov 2025 14:32:45 -0600
Subject: [PATCH 7/8] [ci] Skip memory impact analysis for release and beta
 branches (#11740)

---
 script/determine-jobs.py            | 15 +++++++
 script/helpers.py                   | 45 ++++++++++++++++---
 tests/script/test_determine_jobs.py | 70 +++++++++++++++++++++++++++++
 tests/script/test_helpers.py        |  7 +++
 4 files changed, 130 insertions(+), 7 deletions(-)

diff --git a/script/determine-jobs.py b/script/determine-jobs.py
index 6f908b7150..e9d17d8fe5 100755
--- a/script/determine-jobs.py
+++ b/script/determine-jobs.py
@@ -63,6 +63,7 @@ from helpers import (
     get_components_from_integration_fixtures,
     get_components_with_dependencies,
     get_cpp_changed_components,
+    get_target_branch,
     git_ls_files,
     parse_test_filename,
     root_path,
@@ -471,6 +472,20 @@ def detect_memory_impact_config(
         - platform: platform name for the merged build
         - use_merged_config: "true" (always use merged config)
     """
+    # Skip memory impact analysis for release* or beta* branches
+    # These branches typically contain many merged changes from dev, and building
+    # all components at once would produce nonsensical memory impact results.
+    # Memory impact analysis is most useful for focused PRs targeting dev.
+    target_branch = get_target_branch()
+    if target_branch and (
+        target_branch.startswith("release") or target_branch.startswith("beta")
+    ):
+        print(
+            f"Memory impact: Skipping analysis for target branch {target_branch} "
+            f"(would try to build all components at once, giving nonsensical results)",
+            file=sys.stderr,
+        )
+        return {"should_run": "false"}
 
     # Get actually changed files (not dependencies)
     files = changed_files(branch)
diff --git a/script/helpers.py b/script/helpers.py
index 5b2fe6cd06..1039ef39ac 100644
--- a/script/helpers.py
+++ b/script/helpers.py
@@ -196,6 +196,20 @@ def splitlines_no_ends(string: str) -> list[str]:
     return [s.strip() for s in string.splitlines()]
 
 
+@cache
+def _get_github_event_data() -> dict | None:
+    """Read and parse GitHub event file (cached).
+
+    Returns:
+        Parsed event data dictionary, or None if not available
+    """
+    github_event_path = os.environ.get("GITHUB_EVENT_PATH")
+    if github_event_path and os.path.exists(github_event_path):
+        with open(github_event_path) as f:
+            return json.load(f)
+    return None
+
+
 def _get_pr_number_from_github_env() -> str | None:
     """Extract PR number from GitHub environment variables.
 
@@ -208,13 +222,30 @@ def _get_pr_number_from_github_env() -> str | None:
         return github_ref.split("/pull/")[1].split("/")[0]
 
     # Fallback to GitHub event file
-    github_event_path = os.environ.get("GITHUB_EVENT_PATH")
-    if github_event_path and os.path.exists(github_event_path):
-        with open(github_event_path) as f:
-            event_data = json.load(f)
-            pr_data = event_data.get("pull_request", {})
-            if pr_number := pr_data.get("number"):
-                return str(pr_number)
+    if event_data := _get_github_event_data():
+        pr_data = event_data.get("pull_request", {})
+        if pr_number := pr_data.get("number"):
+            return str(pr_number)
+
+    return None
+
+
+def get_target_branch() -> str | None:
+    """Get the target branch from GitHub environment variables.
+
+    Returns:
+        Target branch name (e.g., "dev", "release", "beta"), or None if not in PR context
+    """
+    # First try GITHUB_BASE_REF (set for pull_request events)
+    if base_ref := os.environ.get("GITHUB_BASE_REF"):
+        return base_ref
+
+    # Fallback to GitHub event file
+    if event_data := _get_github_event_data():
+        pr_data = event_data.get("pull_request", {})
+        base_data = pr_data.get("base", {})
+        if ref := base_data.get("ref"):
+            return ref
 
     return None
 
diff --git a/tests/script/test_determine_jobs.py b/tests/script/test_determine_jobs.py
index e084e2e398..9f12d7ffcf 100644
--- a/tests/script/test_determine_jobs.py
+++ b/tests/script/test_determine_jobs.py
@@ -1240,3 +1240,73 @@ def test_detect_memory_impact_config_filters_incompatible_esp8266_on_esp32(
     )
 
     assert result["use_merged_config"] == "true"
+
+
+def test_detect_memory_impact_config_skips_release_branch(tmp_path: Path) -> None:
+    """Test that memory impact analysis is skipped for release* branches."""
+    # Create test directory structure with components that have tests
+    tests_dir = tmp_path / "tests" / "components"
+    wifi_dir = tests_dir / "wifi"
+    wifi_dir.mkdir(parents=True)
+    (wifi_dir / "test.esp32-idf.yaml").write_text("test: wifi")
+
+    with (
+        patch.object(determine_jobs, "root_path", str(tmp_path)),
+        patch.object(helpers, "root_path", str(tmp_path)),
+        patch.object(determine_jobs, "changed_files") as mock_changed_files,
+        patch.object(determine_jobs, "get_target_branch", return_value="release"),
+    ):
+        mock_changed_files.return_value = ["esphome/components/wifi/wifi.cpp"]
+        determine_jobs._component_has_tests.cache_clear()
+
+        result = determine_jobs.detect_memory_impact_config()
+
+    # Memory impact should be skipped for release branch
+    assert result["should_run"] == "false"
+
+
+def test_detect_memory_impact_config_skips_beta_branch(tmp_path: Path) -> None:
+    """Test that memory impact analysis is skipped for beta* branches."""
+    # Create test directory structure with components that have tests
+    tests_dir = tmp_path / "tests" / "components"
+    wifi_dir = tests_dir / "wifi"
+    wifi_dir.mkdir(parents=True)
+    (wifi_dir / "test.esp32-idf.yaml").write_text("test: wifi")
+
+    with (
+        patch.object(determine_jobs, "root_path", str(tmp_path)),
+        patch.object(helpers, "root_path", str(tmp_path)),
+        patch.object(determine_jobs, "changed_files") as mock_changed_files,
+        patch.object(determine_jobs, "get_target_branch", return_value="beta"),
+    ):
+        mock_changed_files.return_value = ["esphome/components/wifi/wifi.cpp"]
+        determine_jobs._component_has_tests.cache_clear()
+
+        result = determine_jobs.detect_memory_impact_config()
+
+    # Memory impact should be skipped for beta branch
+    assert result["should_run"] == "false"
+
+
+def test_detect_memory_impact_config_runs_for_dev_branch(tmp_path: Path) -> None:
+    """Test that memory impact analysis runs for dev branch."""
+    # Create test directory structure with components that have tests
+    tests_dir = tmp_path / "tests" / "components"
+    wifi_dir = tests_dir / "wifi"
+    wifi_dir.mkdir(parents=True)
+    (wifi_dir / "test.esp32-idf.yaml").write_text("test: wifi")
+
+    with (
+        patch.object(determine_jobs, "root_path", str(tmp_path)),
+        patch.object(helpers, "root_path", str(tmp_path)),
+        patch.object(determine_jobs, "changed_files") as mock_changed_files,
+        patch.object(determine_jobs, "get_target_branch", return_value="dev"),
+    ):
+        mock_changed_files.return_value = ["esphome/components/wifi/wifi.cpp"]
+        determine_jobs._component_has_tests.cache_clear()
+
+        result = determine_jobs.detect_memory_impact_config()
+
+    # Memory impact should run for dev branch
+    assert result["should_run"] == "true"
+    assert result["components"] == ["wifi"]
diff --git a/tests/script/test_helpers.py b/tests/script/test_helpers.py
index 1bfffef51c..c51273f298 100644
--- a/tests/script/test_helpers.py
+++ b/tests/script/test_helpers.py
@@ -31,6 +31,13 @@ print_file_list = helpers.print_file_list
 get_all_dependencies = helpers.get_all_dependencies
 
 
+@pytest.fixture(autouse=True)
+def clear_helpers_cache() -> None:
+    """Clear cached functions before each test."""
+    helpers._get_github_event_data.cache_clear()
+    helpers._get_changed_files_github_actions.cache_clear()
+
+
 @pytest.mark.parametrize(
     ("github_ref", "expected_pr_number"),
     [

From 20b6e0d5c239d949a89f61a528733772f5c3166b Mon Sep 17 00:00:00 2001
From: Clyde Stubbs <2366188+clydebarrow@users.noreply.github.com>
Date: Thu, 6 Nov 2025 09:37:38 +1000
Subject: [PATCH 8/8] [lvgl] Allow text substitution for NaN (#11712)

---
 esphome/components/lvgl/helpers.py       | 39 ++++++++++++++++++++----
 esphome/components/lvgl/lv_validation.py | 16 ++++++++--
 esphome/components/lvgl/schemas.py       |  3 +-
 tests/components/lvgl/lvgl-package.yaml  |  6 ++++
 4 files changed, 55 insertions(+), 9 deletions(-)

diff --git a/esphome/components/lvgl/helpers.py b/esphome/components/lvgl/helpers.py
index 8d5b6354bb..c2bd58f71c 100644
--- a/esphome/components/lvgl/helpers.py
+++ b/esphome/components/lvgl/helpers.py
@@ -3,6 +3,8 @@ import re
 from esphome import config_validation as cv
 from esphome.const import CONF_ARGS, CONF_FORMAT
 
+CONF_IF_NAN = "if_nan"
+
 lv_uses = {
     "USER_DATA",
     "LOG",
@@ -21,23 +23,48 @@ lv_fonts_used = set()
 esphome_fonts_used = set()
 lvgl_components_required = set()
 
-
-def validate_printf(value):
-    cfmt = r"""
+# noqa
+f_regex = re.compile(
+    r"""
     (                                  # start of capture group 1
     %                                  # literal "%"
-    (?:[-+0 #]{0,5})                   # optional flags
+    [-+0 #]{0,5}                   # optional flags
+    (?:\d+|\*)?                        # width
+    (?:\.(?:\d+|\*))?                  # precision
+    (?:h|l|ll|w|I|I32|I64)?            # size
+    f                                  # type
+    )
+    """,
+    flags=re.VERBOSE,
+)
+# noqa
+c_regex = re.compile(
+    r"""
+    (                                  # start of capture group 1
+    %                                  # literal "%"
+    [-+0 #]{0,5}                   # optional flags
     (?:\d+|\*)?                        # width
     (?:\.(?:\d+|\*))?                  # precision
     (?:h|l|ll|w|I|I32|I64)?            # size
     [cCdiouxXeEfgGaAnpsSZ]             # type
     )
-    """  # noqa
-    matches = re.findall(cfmt, value[CONF_FORMAT], flags=re.VERBOSE)
+    """,
+    flags=re.VERBOSE,
+)
+
+
+def validate_printf(value):
+    format_string = value[CONF_FORMAT]
+    matches = c_regex.findall(format_string)
     if len(matches) != len(value[CONF_ARGS]):
         raise cv.Invalid(
             f"Found {len(matches)} printf-patterns ({', '.join(matches)}), but {len(value[CONF_ARGS])} args were given!"
         )
+
+    if value.get(CONF_IF_NAN) and len(f_regex.findall(format_string)) != 1:
+        raise cv.Invalid(
+            "Use of 'if_nan' requires a single valid printf-pattern of type %f"
+        )
     return value
 
 
diff --git a/esphome/components/lvgl/lv_validation.py b/esphome/components/lvgl/lv_validation.py
index 9fe72128ce..045258555c 100644
--- a/esphome/components/lvgl/lv_validation.py
+++ b/esphome/components/lvgl/lv_validation.py
@@ -33,7 +33,13 @@ from .defines import (
     call_lambda,
     literal,
 )
-from .helpers import add_lv_use, esphome_fonts_used, lv_fonts_used, requires_component
+from .helpers import (
+    CONF_IF_NAN,
+    add_lv_use,
+    esphome_fonts_used,
+    lv_fonts_used,
+    requires_component,
+)
 from .types import lv_font_t, lv_gradient_t
 
 opacity_consts = LvConstant("LV_OPA_", "TRANSP", "COVER")
@@ -412,7 +418,13 @@ class TextValidator(LValidator):
                 str_args = [str(x) for x in value[CONF_ARGS]]
                 arg_expr = cg.RawExpression(",".join(str_args))
                 format_str = cpp_string_escape(format_str)
-                return literal(f"str_sprintf({format_str}, {arg_expr}).c_str()")
+                sprintf_str = f"str_sprintf({format_str}, {arg_expr}).c_str()"
+                if nanval := value.get(CONF_IF_NAN):
+                    nanval = cpp_string_escape(nanval)
+                    return literal(
+                        f"(std::isfinite({arg_expr}) ? {sprintf_str} : {nanval})"
+                    )
+                return literal(sprintf_str)
             if time_format := value.get(CONF_TIME_FORMAT):
                 source = value[CONF_TIME]
                 if isinstance(source, Lambda):
diff --git a/esphome/components/lvgl/schemas.py b/esphome/components/lvgl/schemas.py
index dd248d0b94..0dcf420f24 100644
--- a/esphome/components/lvgl/schemas.py
+++ b/esphome/components/lvgl/schemas.py
@@ -20,7 +20,7 @@ from esphome.core.config import StartupTrigger
 
 from . import defines as df, lv_validation as lvalid
 from .defines import CONF_TIME_FORMAT, LV_GRAD_DIR
-from .helpers import requires_component, validate_printf
+from .helpers import CONF_IF_NAN, requires_component, validate_printf
 from .layout import (
     FLEX_OBJ_SCHEMA,
     GRID_CELL_SCHEMA,
@@ -54,6 +54,7 @@ PRINTF_TEXT_SCHEMA = cv.All(
         {
             cv.Required(CONF_FORMAT): cv.string,
             cv.Optional(CONF_ARGS, default=list): cv.ensure_list(cv.lambda_),
+            cv.Optional(CONF_IF_NAN): cv.string,
         },
     ),
     validate_printf,
diff --git a/tests/components/lvgl/lvgl-package.yaml b/tests/components/lvgl/lvgl-package.yaml
index 8ac9a60e2d..b122d10f04 100644
--- a/tests/components/lvgl/lvgl-package.yaml
+++ b/tests/components/lvgl/lvgl-package.yaml
@@ -726,6 +726,12 @@ lvgl:
                 - logger.log:
                     format: "Spinbox value is %f"
                     args: [x]
+                - lvgl.label.update:
+                    id: hello_label
+                    text:
+                      format: "value is %.1f now"
+                      args: [x]
+                      if_nan: "Value unknown"
         - button:
             styles: spin_button
             id: spin_down