Merge branch 'compile-time-has-overridden-loop' into integration

# Conflicts:
#	esphome/core/application.cpp

esphome/components/improv_serial/__init__.py

@@ -43,3 +43,4 @@ async def to_code(config):
     var = cg.new_Pvariable(config[CONF_ID])
     await cg.register_component(var, config)
     await improv_base.setup_improv_core(var, config, "improv_serial")
+    cg.add_define("USE_IMPROV_SERIAL")

esphome/components/wifi/wifi_component.cpp

@@ -2122,7 +2122,7 @@ bool WiFiComponent::can_proceed() {
 #endif
 
 void WiFiComponent::set_reboot_timeout(uint32_t reboot_timeout) { this->reboot_timeout_ = reboot_timeout; }
-bool WiFiComponent::is_connected() {
+bool WiFiComponent::is_connected() const {
   return this->state_ == WIFI_COMPONENT_STATE_STA_CONNECTED &&
          this->wifi_sta_connect_status_() == WiFiSTAConnectStatus::CONNECTED && !this->error_from_callback_;
 }

esphome/components/wifi/wifi_component.h

@@ -443,7 +443,7 @@ class WiFiComponent : public Component {
 
   void set_reboot_timeout(uint32_t reboot_timeout);
 
-  bool is_connected();
+  bool is_connected() const;
 
   void set_power_save_mode(WiFiPowerSaveMode power_save);
   void set_min_auth_mode(WifiMinAuthMode min_auth_mode) { min_auth_mode_ = min_auth_mode; }
@@ -677,7 +677,7 @@ class WiFiComponent : public Component {
   bool wifi_apply_hostname_();
   bool wifi_sta_connect_(const WiFiAP &ap);
   void wifi_pre_setup_();
-  WiFiSTAConnectStatus wifi_sta_connect_status_();
+  WiFiSTAConnectStatus wifi_sta_connect_status_() const;
   bool wifi_scan_start_(bool passive);
 
 #ifdef USE_WIFI_AP

esphome/components/wifi/wifi_component_esp8266.cpp

@@ -623,7 +623,7 @@ void WiFiComponent::wifi_pre_setup_() {
   this->wifi_mode_(false, false);
 }
 
-WiFiSTAConnectStatus WiFiComponent::wifi_sta_connect_status_() {
+WiFiSTAConnectStatus WiFiComponent::wifi_sta_connect_status_() const {
   station_status_t status = wifi_station_get_connect_status();
   if (status == STATION_GOT_IP)
     return WiFiSTAConnectStatus::CONNECTED;

esphome/components/wifi/wifi_component_esp_idf.cpp

@@ -921,7 +921,7 @@ void WiFiComponent::wifi_process_event_(IDFWiFiEvent *data) {
   }
 }
 
-WiFiSTAConnectStatus WiFiComponent::wifi_sta_connect_status_() {
+WiFiSTAConnectStatus WiFiComponent::wifi_sta_connect_status_() const {
   if (s_sta_connected && this->got_ipv4_address_) {
 #if USE_NETWORK_IPV6 && (USE_NETWORK_MIN_IPV6_ADDR_COUNT > 0)
     if (this->num_ipv6_addresses_ >= USE_NETWORK_MIN_IPV6_ADDR_COUNT) {

esphome/components/wifi/wifi_component_libretiny.cpp

@@ -634,7 +634,7 @@ void WiFiComponent::wifi_pre_setup_() {
   // Make sure WiFi is in clean state before anything starts
   this->wifi_mode_(false, false);
 }
-WiFiSTAConnectStatus WiFiComponent::wifi_sta_connect_status_() {
+WiFiSTAConnectStatus WiFiComponent::wifi_sta_connect_status_() const {
   // Use state machine instead of querying WiFi.status() directly
   // State is updated in main loop from queued events, ensuring thread safety
   switch (s_sta_state) {

esphome/components/wifi/wifi_component_pico_w.cpp

@@ -120,7 +120,7 @@ const char *get_disconnect_reason_str(uint8_t reason) {
   return "UNKNOWN";
 }
 
-WiFiSTAConnectStatus WiFiComponent::wifi_sta_connect_status_() {
+WiFiSTAConnectStatus WiFiComponent::wifi_sta_connect_status_() const {
   // Use cyw43_wifi_link_status instead of cyw43_tcpip_link_status because the Arduino
   // framework's __wrap_cyw43_cb_tcpip_init is a no-op — the SDK's internal netif
   // (cyw43_state.netif[]) is never initialized. cyw43_tcpip_link_status checks that netif's

esphome/core/application.cpp

@@ -82,7 +82,10 @@ static void insertion_sort_by_priority(Iterator first, Iterator last) {
   }
 }
 
-void Application::register_component_(Component *comp) {
+void Application::register_component_impl_(Component *comp, bool has_loop) {
+  if (has_loop) {
+    comp->component_state_ |= COMPONENT_HAS_LOOP;
+  }
   this->components_.push_back(comp);
 #ifdef USE_SETUP_HEAP_STATS
   if (global_setup_heap_stats == nullptr) {
@@ -93,7 +96,6 @@ void Application::register_component_(Component *comp) {
   global_setup_heap_stats->record_component_registered(comp);
 #endif
 }
-
 void Application::setup() {
   ESP_LOGI(TAG, "Running through setup()");
   ESP_LOGV(TAG, "Sorting components by setup priority");
@@ -402,16 +404,8 @@ void Application::teardown_components(uint32_t timeout_ms) {
 }
 
 void Application::calculate_looping_components_() {
-  // Count total components that need looping
-  size_t total_looping = 0;
-  for (auto *obj : this->components_) {
-    if (obj->has_overridden_loop()) {
-      total_looping++;
-    }
-  }
-
-  // Initialize FixedVector with exact size - no reallocation possible
-  this->looping_components_.init(total_looping);
+  // FixedVector capacity was pre-initialized by codegen with the exact count
+  // of components that override loop(), computed at C++ compile time.
 
   // Add all components with loop override that aren't already LOOP_DONE
   // Some components (like logger) may call disable_loop() during initialization

esphome/core/application.h

@@ -5,6 +5,7 @@
 #include <limits>
 #include <span>
 #include <string>
+#include <type_traits>
 #include <vector>
 #include "esphome/core/component.h"
 #include "esphome/core/defines.h"
@@ -671,7 +672,14 @@ class Application {
 #endif
 #endif
 
-  void register_component_(Component *comp);
+  /// Register a component, detecting loop() override at compile time.
+  /// The template resolves &T::loop vs &Component::loop as a constexpr bool
+  /// and forwards it to register_component_impl_ which stores it in component_state_.
+  template<typename T> void register_component_(T *comp) {
+    this->register_component_impl_(comp, !std::is_same_v<decltype(&T::loop), decltype(&Component::loop)>);
+  }
+
+  void register_component_impl_(Component *comp, bool has_loop);
 
   void calculate_looping_components_();
   void add_looping_components_by_state_(bool match_loop_done);

esphome/core/component.cpp

@@ -510,18 +510,6 @@ void Component::set_setup_priority(float priority) {
 }
 #endif
 
-bool Component::has_overridden_loop() const {
-#if defined(USE_HOST) || defined(CLANG_TIDY)
-  return true;
-#else
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wpmf-conversions"
-  bool loop_overridden = (void *) (this->*(&Component::loop)) != (void *) (&Component::loop);
-#pragma GCC diagnostic pop
-  return loop_overridden;
-#endif
-}
-
 PollingComponent::PollingComponent(uint32_t update_interval) : update_interval_(update_interval) {}
 
 void PollingComponent::call_setup() {

esphome/core/component.h

@@ -76,6 +76,8 @@ inline constexpr uint8_t STATUS_LED_MASK = 0x18;
 inline constexpr uint8_t STATUS_LED_OK = 0x00;
 inline constexpr uint8_t STATUS_LED_WARNING = 0x08;
 inline constexpr uint8_t STATUS_LED_ERROR = 0x10;
+// Component loop override flag uses bit 5 (set at registration time)
+inline constexpr uint8_t COMPONENT_HAS_LOOP = 0x20;
 
 // Remove before 2026.8.0
 enum class RetryResult { DONE, RETRY };
@@ -271,7 +273,7 @@ class Component {
    */
   void status_momentary_error(const char *name, uint32_t length = 5000);
 
-  bool has_overridden_loop() const;
+  bool has_overridden_loop() const { return (this->component_state_ & COMPONENT_HAS_LOOP) != 0; }
 
   /** Set where this component was loaded from for some debug messages.
    *
@@ -510,7 +512,8 @@ class Component {
   /// Bits 0-2: Component state (0x00=CONSTRUCTION, 0x01=SETUP, 0x02=LOOP, 0x03=FAILED, 0x04=LOOP_DONE)
   /// Bit 3: STATUS_LED_WARNING
   /// Bit 4: STATUS_LED_ERROR
-  /// Bits 5-7: Unused - reserved for future expansion
+  /// Bit 5: Has overridden loop() (set at registration time)
+  /// Bits 6-7: Unused - reserved for future expansion
   uint8_t component_state_{0x00};
   volatile bool pending_enable_loop_{false};  ///< ISR-safe flag for enable_loop_soon_any_context
 };

esphome/core/config.py

@@ -504,6 +504,39 @@ async def _add_controller_registry_define() -> None:
         cg.add_define("CONTROLLER_REGISTRY_MAX", controller_count)
 
 
+@coroutine_with_priority(CoroPriority.FINAL)
+async def _add_looping_components() -> None:
+    # Emit a constexpr that computes the looping component count at C++ compile time
+    # and pre-init the FixedVector with the exact capacity. Uses std::is_same_v to
+    # detect loop() overrides. The constexpr goes in main.cpp's global section where
+    # all component types are in scope. calculate_looping_components_() then skips
+    # the counting pass and only does the two population passes.
+    entries = CORE.data.get("looping_component_entries", [])
+    if not entries:
+        return
+
+    # Build constexpr sum for the exact count
+    terms = [
+        f"(!std::is_same_v<decltype(&{cpp_type}::loop), decltype(&Component::loop)>)"
+        for cpp_type in entries
+    ]
+    constexpr_expr = " + \\\n  ".join(terms)
+    cg.add_global(
+        cg.RawStatement(
+            f"static constexpr size_t ESPHOME_LOOPING_COMPONENT_COUNT = \\\n"
+            f"  {constexpr_expr};"
+        )
+    )
+
+    # Pre-init FixedVector with exact capacity so calculate_looping_components_()
+    # can skip the counting pass
+    cg.add(
+        cg.RawExpression(
+            "App.looping_components_.init(ESPHOME_LOOPING_COMPONENT_COUNT)"
+        )
+    )
+
+
 @coroutine_with_priority(CoroPriority.CORE)
 async def to_code(config: ConfigType) -> None:
     cg.add_global(cg.global_ns.namespace("esphome").using)
@@ -527,6 +560,7 @@ async def to_code(config: ConfigType) -> None:
 
     CORE.add_job(_add_platform_defines)
     CORE.add_job(_add_controller_registry_define)
+    CORE.add_job(_add_looping_components)
 
     CORE.add_job(_add_automations, config)
 

esphome/core/defines.h

@@ -57,6 +57,7 @@
 #define USE_HOMEASSISTANT_TIME
 #define USE_HTTP_REQUEST_OTA_WATCHDOG_TIMEOUT 8000  // NOLINT
 #define USE_IMAGE
+#define USE_IMPROV_SERIAL
 #define USE_IMPROV_SERIAL_NEXT_URL
 #define USE_INFRARED
 #define USE_IR_RF

esphome/cpp_helpers.py

@@ -80,6 +80,11 @@ async def register_component(var, config):
         add(var.set_component_source(LogStringLiteral(name)))
 
     add(App.register_component_(var))
+
+    # Collect C++ type for compile-time looping component count
+    comp_entries = CORE.data.setdefault("looping_component_entries", [])
+    comp_entries.append(str(var.base.type))
+
     return var
 
 

tests/unit_tests/test_cpp_helpers.py

@@ -14,7 +14,11 @@ async def test_gpio_pin_expression__conf_is_none(monkeypatch):
 
 @pytest.mark.asyncio
 async def test_register_component(monkeypatch):
-    var = Mock(base="foo.bar")
+    base_mock = Mock()
+    base_mock.__str__ = lambda self: "foo.bar"
+    base_mock.type = Mock()
+    base_mock.type.__str__ = lambda self: "foo::Bar"
+    var = Mock(base=base_mock)
 
     app_mock = Mock(register_component_=Mock(return_value=var))
     monkeypatch.setattr(ch, "App", app_mock)
@@ -46,7 +50,11 @@ async def test_register_component__no_component_id(monkeypatch):
 
 @pytest.mark.asyncio
 async def test_register_component__with_setup_priority(monkeypatch):
-    var = Mock(base="foo.bar")
+    base_mock = Mock()
+    base_mock.__str__ = lambda self: "foo.bar"
+    base_mock.type = Mock()
+    base_mock.type.__str__ = lambda self: "foo::Bar"
+    var = Mock(base=base_mock)
 
     app_mock = Mock(register_component_=Mock(return_value=var))
     monkeypatch.setattr(ch, "App", app_mock)