Merge branch 'text_sensor_avoid_copies_const_ref' into integration

esphome/components/sensor/sensor.cpp

@@ -76,9 +76,7 @@ StateClass Sensor::get_state_class() {
 
 void Sensor::publish_state(float state) {
   this->raw_state = state;
-
-  // Call raw callbacks (before filters)
-  this->callbacks_.call_first(this->raw_count_, state);
+  this->raw_callback_.call(state);
 
   ESP_LOGV(TAG, "'%s': Received new state %f", this->name_.c_str(), state);
 
@@ -89,12 +87,9 @@ void Sensor::publish_state(float state) {
   }
 }
 
-void Sensor::add_on_state_callback(std::function<void(float)> &&callback) {
-  this->callbacks_.add_second(std::move(callback));
-}
-
+void Sensor::add_on_state_callback(std::function<void(float)> &&callback) { this->callback_.add(std::move(callback)); }
 void Sensor::add_on_raw_state_callback(std::function<void(float)> &&callback) {
-  this->callbacks_.add_first(std::move(callback), &this->raw_count_);
+  this->raw_callback_.add(std::move(callback));
 }
 
 void Sensor::add_filter(Filter *filter) {
@@ -134,10 +129,7 @@ void Sensor::internal_send_state_to_frontend(float state) {
   this->state = state;
   ESP_LOGD(TAG, "'%s': Sending state %.5f %s with %d decimals of accuracy", this->get_name().c_str(), state,
            this->get_unit_of_measurement_ref().c_str(), this->get_accuracy_decimals());
-
-  // Call filtered callbacks (after filters)
-  this->callbacks_.call_second(this->raw_count_, state);
-
+  this->callback_.call(state);
 #if defined(USE_SENSOR) && defined(USE_CONTROLLER_REGISTRY)
   ControllerRegistry::notify_sensor_update(this);
 #endif

esphome/components/sensor/sensor.h

@@ -125,7 +125,8 @@ class Sensor : public EntityBase, public EntityBase_DeviceClass, public EntityBa
   void internal_send_state_to_frontend(float state);
 
  protected:
-  PartitionedCallbackManager<void(float)> callbacks_;
+  LazyCallbackManager<void(float)> raw_callback_;  ///< Storage for raw state callbacks.
+  LazyCallbackManager<void(float)> callback_;      ///< Storage for filtered state callbacks.
 
   Filter *filter_list_{nullptr};  ///< Store all active filters.
 
@@ -140,8 +141,6 @@ class Sensor : public EntityBase, public EntityBase_DeviceClass, public EntityBa
     uint8_t force_update : 1;
     uint8_t reserved : 5;  // Reserved for future use
   } sensor_flags_{};
-
-  uint8_t raw_count_{0};  ///< Number of raw callbacks (partition point in callbacks_ vector)
 };
 
 }  // namespace sensor

esphome/components/text_sensor/text_sensor.cpp

@@ -30,9 +30,7 @@ void TextSensor::publish_state(const std::string &state) {
 #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
   this->raw_state = state;
 #pragma GCC diagnostic pop
-
-  // Call raw callbacks (before filters)
-  this->callbacks_.call_first(this->raw_count_, state);
+  this->raw_callback_.call(state);
 
   ESP_LOGV(TAG, "'%s': Received new state %s", this->name_.c_str(), state.c_str());
 
@@ -74,11 +72,10 @@ void TextSensor::clear_filters() {
 }
 
 void TextSensor::add_on_state_callback(std::function<void(const std::string &)> callback) {
-  this->callbacks_.add_second(std::move(callback));
+  this->callback_.add(std::move(callback));
 }
-
 void TextSensor::add_on_raw_state_callback(std::function<void(const std::string &)> callback) {
-  this->callbacks_.add_first(std::move(callback), &this->raw_count_);
+  this->raw_callback_.add(std::move(callback));
 }
 
 std::string TextSensor::get_state() const { return this->state; }
@@ -93,10 +90,7 @@ void TextSensor::internal_send_state_to_frontend(const std::string &state) {
   this->state = state;
   this->set_has_state(true);
   ESP_LOGD(TAG, "'%s': Sending state '%s'", this->name_.c_str(), state.c_str());
-
-  // Call filtered callbacks (after filters)
-  this->callbacks_.call_second(this->raw_count_, state);
-
+  this->callback_.call(state);
 #if defined(USE_TEXT_SENSOR) && defined(USE_CONTROLLER_REGISTRY)
   ControllerRegistry::notify_text_sensor_update(this);
 #endif

esphome/components/text_sensor/text_sensor.h

@@ -65,11 +65,10 @@ class TextSensor : public EntityBase, public EntityBase_DeviceClass {
   void internal_send_state_to_frontend(const std::string &state);
 
  protected:
-  PartitionedCallbackManager<void(const std::string &)> callbacks_;
+  LazyCallbackManager<void(const std::string &)> raw_callback_;  ///< Storage for raw state callbacks.
+  LazyCallbackManager<void(const std::string &)> callback_;      ///< Storage for filtered state callbacks.
 
   Filter *filter_list_{nullptr};  ///< Store all active filters.
-
-  uint8_t raw_count_{0};  ///< Number of raw callbacks (partition point in callbacks_ vector)
 };
 
 }  // namespace text_sensor

esphome/core/helpers.h

@@ -964,71 +964,48 @@ template<typename... Ts> class CallbackManager<void(Ts...)> {
   std::vector<std::function<void(Ts...)>> callbacks_;
 };
 
-template<typename... X> class PartitionedCallbackManager;
+template<typename... X> class LazyCallbackManager;
 
-/** Helper class for callbacks partitioned into two sections.
+/** Lazy-allocating callback manager that only allocates memory when callbacks are registered.
  *
- * Uses a single vector partitioned into two sections: [first_0, ..., first_m-1, second_0, ..., second_n-1]
- * The partition point is tracked externally by the caller (typically stored in the entity class for optimal alignment).
+ * This is a drop-in replacement for CallbackManager that saves memory when no callbacks
+ * are registered (common case after the Controller Registry eliminated per-entity callbacks
+ * from API and web_server components).
  *
- * Memory efficient: Only stores a single pointer (4 bytes on 32-bit platforms, 8 bytes on 64-bit platforms).
- * The partition count lives in the entity class where it can be packed with other small fields to avoid padding waste.
- *
- * Design rationale: The asymmetric API (add_first takes first_count*, while call_first/call_second take it by value)
- * is intentional - add_first must increment the count, while call methods only read it. This avoids storing first_count
- * internally, saving memory per instance.
+ * Memory overhead comparison (32-bit systems):
+ * - CallbackManager: 12 bytes (empty std::vector)
+ * - LazyCallbackManager: 4 bytes (nullptr unique_ptr)
  *
  * @tparam Ts The arguments for the callbacks, wrapped in void().
  */
-template<typename... Ts> class PartitionedCallbackManager<void(Ts...)> {
+template<typename... Ts> class LazyCallbackManager<void(Ts...)> {
  public:
-  /// Add a callback to the first partition.
-  void add_first(std::function<void(Ts...)> &&callback, uint8_t *first_count) {
+  /// Add a callback to the list. Allocates the underlying CallbackManager on first use.
+  void add(std::function<void(Ts...)> &&callback) {
     if (!this->callbacks_) {
-      this->callbacks_ = make_unique<std::vector<std::function<void(Ts...)>>>();
+      this->callbacks_ = make_unique<CallbackManager<void(Ts...)>>();
     }
-
-    // Add to first partition: append then rotate into position
-    this->callbacks_->push_back(std::move(callback));
-    // Avoid potential underflow: rewrite comparison to not subtract from size()
-    if (*first_count + 1 < this->callbacks_->size()) {
-      // Use std::rotate to maintain registration order in second partition
-      std::rotate(this->callbacks_->begin() + *first_count, this->callbacks_->end() - 1, this->callbacks_->end());
-    }
-    (*first_count)++;
+    this->callbacks_->add(std::move(callback));
   }
 
-  /// Add a callback to the second partition.
-  void add_second(std::function<void(Ts...)> &&callback) {
-    if (!this->callbacks_) {
-      this->callbacks_ = make_unique<std::vector<std::function<void(Ts...)>>>();
-    }
-
-    // Add to second partition: just append (already at end after first partition)
-    this->callbacks_->push_back(std::move(callback));
-  }
-
-  /// Call all callbacks in the first partition.
-  void call_first(uint8_t first_count, Ts... args) {
+  /// Call all callbacks in this manager. No-op if no callbacks registered.
+  void call(Ts... args) {
     if (this->callbacks_) {
-      for (size_t i = 0; i < first_count; i++) {
-        (*this->callbacks_)[i](args...);
-      }
+      this->callbacks_->call(args...);
     }
   }
 
-  /// Call all callbacks in the second partition.
-  void call_second(uint8_t first_count, Ts... args) {
-    if (this->callbacks_) {
-      for (size_t i = first_count; i < this->callbacks_->size(); i++) {
-        (*this->callbacks_)[i](args...);
-      }
-    }
-  }
+  /// Return the number of registered callbacks.
+  size_t size() const { return this->callbacks_ ? this->callbacks_->size() : 0; }
+
+  /// Check if any callbacks are registered.
+  bool empty() const { return !this->callbacks_ || this->callbacks_->size() == 0; }
+
+  /// Call all callbacks in this manager.
+  void operator()(Ts... args) { this->call(args...); }
 
  protected:
-  /// Partitioned callback storage: [first_0, ..., first_m-1, second_0, ..., second_n-1]
-  std::unique_ptr<std::vector<std::function<void(Ts...)>>> callbacks_;
+  std::unique_ptr<CallbackManager<void(Ts...)>> callbacks_;
 };
 
 template<typename... X> class LazyCallbackManager;