Regenerate api_pb2 for SerialProxySetModeRequest after merging dev

A generated decodable message that lost its decode() would now fail to compile instead of
silently keeping its defaults. The asserts cover exactly the classes that derive from
ProtoDecodableMessage, under one ifdef per run instead of one per line, and the generator
tests pin the inline decode() wrapper, its absence on fixed vector messages, and the
this-> free static body.

esphome/components/api/api_connection.cpp

@@ -2269,7 +2269,12 @@ bool APIConnection::send_message_(uint32_t payload_size, uint16_t message_type,
   // Capacity reserved above, cannot fail
   (void) shared_buf.resize(write_start + payload_size);
   ProtoWriteBuffer buffer{&shared_buf, write_start};
-  encode_fn(msg, buffer PROTO_ENCODE_DEBUG_INIT(&shared_buf));
+  uint8_t *end = encode_fn(msg, buffer PROTO_ENCODE_DEBUG_INIT(&shared_buf));
+#ifdef ESPHOME_DEBUG_API
+  assert(end == shared_buf.data() + shared_buf.size());
+#else
+  (void) end;
+#endif
   return this->send_buffer(ProtoWriteBuffer{&shared_buf}, message_type);
 }
 // encode_to_buffer is defined inline in api_connection.h (ESPHOME_ALWAYS_INLINE)

esphome/components/api/api_connection.h

@@ -346,11 +346,7 @@ class APIConnection final : public APIServerConnectionBase {
   /// Returns false as soon as the TCP buffer is full. Marked nodiscard so we
   /// have no silent failures: every caller must handle (or log) a refusal.
   template<typename T> [[nodiscard]] bool send_message(const T &msg) {
-    if constexpr (T::ESTIMATED_SIZE == 0) {
-      return this->send_message_(0, T::MESSAGE_TYPE, &encode_msg_noop, &msg);
-    } else {
-      return this->send_message_(msg.calculate_size(), T::MESSAGE_TYPE, &proto_encode_msg<T>, &msg);
-    }
+    return this->send_message_(T::calc_size_msg(&msg), T::MESSAGE_TYPE, &T::encode_msg, &msg);
   }
 
   /// Clear the shared write buffer and reserve space for the first message.
@@ -406,16 +402,6 @@ class APIConnection final : public APIServerConnectionBase {
   void process_state_subscriptions_();
 #endif
 
-  // Size thunk — converts void* back to concrete type for direct calculate_size() call
-  template<typename T> static uint32_t calc_size(const void *msg) {
-    return static_cast<const T *>(msg)->calculate_size();
-  }
-
-  // Shared no-op encode thunk for empty messages (ESTIMATED_SIZE == 0)
-  static uint8_t *encode_msg_noop(const void *, ProtoWriteBuffer &buf PROTO_ENCODE_DEBUG_PARAM) {
-    return buf.get_pos();
-  }
-
   // Non-template buffer management for send_message
   bool send_message_(uint32_t payload_size, uint16_t message_type, MessageEncodeFn encode_fn, const void *msg);
 
@@ -434,11 +420,7 @@ class APIConnection final : public APIServerConnectionBase {
   // Hot paths (state/info) go through fill_and_encode_entity_state/info instead.
   // batch_message_type_ is already set by dispatch_message_ before reaching here.
   template<typename T> static uint16_t encode_message_to_buffer(T &msg, APIConnection *conn, uint32_t remaining_size) {
-    if constexpr (T::ESTIMATED_SIZE == 0) {
-      return encode_to_buffer_slow(0, &encode_msg_noop, &msg, conn, remaining_size);
-    } else {
-      return encode_to_buffer_slow(msg.calculate_size(), &proto_encode_msg<T>, &msg, conn, remaining_size);
-    }
+    return encode_to_buffer_slow(T::calc_size_msg(&msg), &T::encode_msg, &msg, conn, remaining_size);
   }
 
   // Non-template core — fills state fields and encodes
@@ -450,7 +432,7 @@ class APIConnection final : public APIServerConnectionBase {
   template<typename T>
   static uint16_t fill_and_encode_entity_state(EntityBase *entity, T &msg, APIConnection *conn,
                                                uint32_t remaining_size) {
-    return fill_and_encode_entity_state(entity, msg, &calc_size<T>, &proto_encode_msg<T>, conn, remaining_size);
+    return fill_and_encode_entity_state(entity, msg, &T::calc_size_msg, &T::encode_msg, conn, remaining_size);
   }
 
   // Non-template core — fills info fields, allocates buffers, and encodes
@@ -462,7 +444,7 @@ class APIConnection final : public APIServerConnectionBase {
   template<typename T>
   static uint16_t fill_and_encode_entity_info(EntityBase *entity, T &msg, APIConnection *conn,
                                               uint32_t remaining_size) {
-    return fill_and_encode_entity_info(entity, msg, &calc_size<T>, &proto_encode_msg<T>, conn, remaining_size);
+    return fill_and_encode_entity_info(entity, msg, &T::calc_size_msg, &T::encode_msg, conn, remaining_size);
   }
 
   // Non-template core — fills device_class, then delegates to fill_and_encode_entity_info
@@ -476,8 +458,8 @@ class APIConnection final : public APIServerConnectionBase {
   static uint16_t fill_and_encode_entity_info_with_device_class(EntityBase *entity, T &msg,
                                                                 StringRef &device_class_field, APIConnection *conn,
                                                                 uint32_t remaining_size) {
-    return fill_and_encode_entity_info_with_device_class(entity, msg, device_class_field, &calc_size<T>,
-                                                         &proto_encode_msg<T>, conn, remaining_size);
+    return fill_and_encode_entity_info_with_device_class(entity, msg, device_class_field, &T::calc_size_msg,
+                                                         &T::encode_msg, conn, remaining_size);
   }
 
 #ifdef USE_VOICE_ASSISTANT

esphome/components/api/api_connection_buffer.h

@@ -46,7 +46,13 @@ inline uint16_t ESPHOME_ALWAYS_INLINE APIConnection::encode_to_buffer(uint32_t c
     return 0;
   }
   ProtoWriteBuffer buffer{&shared_buf, shared_buf.size() - calculated_size};
-  encode_fn(msg, buffer PROTO_ENCODE_DEBUG_INIT(&shared_buf));
+  uint8_t *end = encode_fn(msg, buffer PROTO_ENCODE_DEBUG_INIT(&shared_buf));
+#ifdef ESPHOME_DEBUG_API
+  // A body that writes fewer bytes than calculate_size() promised would ship stale buffer bytes
+  assert(end == shared_buf.data() + shared_buf.size());
+#else
+  (void) end;
+#endif
 
   return total_calculated_size;
 }

esphome/components/api/api_server.cpp

@@ -433,8 +433,9 @@ void APIServer::send_homeassistant_action(const HomeassistantActionRequest &call
     // Home Assistant subscribes to actions shortly *after* authenticating, so actions
     // fired right at connection time (on_client_connected, on_time_sync, ...) can
     // arrive before the subscription and are lost - warn instead of failing silently.
-    ESP_LOGW(TAG, "Home Assistant %s '%s' dropped; %s",
-             call.is_event ? LOG_STR_LITERAL("event") : LOG_STR_LITERAL("action"), call.service.c_str(),
+    ESP_LOGW(TAG, "Home Assistant %s '%.*s' dropped; %s",
+             call.is_event ? LOG_STR_LITERAL("event") : LOG_STR_LITERAL("action"),
+             static_cast<int>(call.service.size()), call.service.empty() ? "" : call.service.c_str(),
              this->is_connected() ? LOG_STR_LITERAL("client has not subscribed to actions (yet)")
                                   : LOG_STR_LITERAL("no client connected"));
   }

esphome/components/api/proto.cpp

@@ -210,77 +210,78 @@ void ProtoWriteBuffer::debug_check_encode_size_(uint32_t field_id, uint32_t expe
 
 #endif
 
-void ProtoDecodableMessage::decode(const uint8_t *buffer, size_t length) {
+void ProtoDecodableMessage::decode_fields(void *msg, const uint8_t *buffer, size_t length, DecodeFieldFn field) {
   const uint8_t *ptr = buffer;
   const uint8_t *end = buffer + length;
 
-  while (ptr < end) {
-    // Parse field header - ptr < end guarantees len >= 1
+  // Single-byte varints dominate, so that case advances the cursor inline.
+  auto read_varint = [&](proto_varint_value_t &value) ESPHOME_ALWAYS_INLINE {
+    if (ptr == end)
+      return false;
+    if (*ptr < 0x80) [[likely]] {
+      value = *ptr++;
+      return true;
+    }
     auto res = ProtoVarInt::parse_non_empty(ptr, end - ptr);
-    if (!res.has_value()) {
+    if (!res.has_value())
+      return false;
+    value = res.value;
+    ptr += res.consumed;
+    return true;
+  };
+
+  while (ptr < end) {
+    proto_varint_value_t tag_value;
+    if (!read_varint(tag_value)) {
       ESP_LOGV(TAG, "Invalid field start at offset %ld", (long) (ptr - buffer));
       return;
     }
 
-    uint32_t tag = static_cast<uint32_t>(res.value);
+    uint32_t tag = static_cast<uint32_t>(tag_value);
     uint32_t field_type = tag & WIRE_TYPE_MASK;
-    uint32_t field_id = tag >> 3;
-    ptr += res.consumed;
+    // Length-delimited fields move this past the length prefix
+    const uint8_t *data = ptr;
+    proto_varint_value_t scalar;
 
-    switch (field_type) {
-      case WIRE_TYPE_VARINT: {  // VarInt
-        res = ProtoVarInt::parse(ptr, end - ptr);
-        if (!res.has_value()) {
-          ESP_LOGV(TAG, "Invalid VarInt at offset %ld", (long) (ptr - buffer));
-          return;
-        }
-        if (!this->decode_varint(field_id, res.value)) {
-          ESP_LOGV(TAG, "Cannot decode VarInt field %" PRIu32 " with value %" PRIu64 "!", field_id,
-                   static_cast<uint64_t>(res.value));
-        }
-        ptr += res.consumed;
-        break;
-      }
-      case WIRE_TYPE_LENGTH_DELIMITED: {  // Length-delimited
-        res = ProtoVarInt::parse(ptr, end - ptr);
-        if (!res.has_value()) {
-          ESP_LOGV(TAG, "Invalid Length Delimited at offset %ld", (long) (ptr - buffer));
-          return;
-        }
-        uint32_t field_length = static_cast<uint32_t>(res.value);
-        ptr += res.consumed;
-        if (field_length > static_cast<size_t>(end - ptr)) {
-          ESP_LOGV(TAG, "Out-of-bounds Length Delimited at offset %ld", (long) (ptr - buffer));
-          return;
-        }
-        if (!this->decode_length(field_id, ProtoLengthDelimited(ptr, field_length))) {
-          ESP_LOGV(TAG, "Cannot decode Length Delimited field %" PRIu32 "!", field_id);
-        }
-        ptr += field_length;
-        break;
-      }
-      case WIRE_TYPE_FIXED32: {  // 32-bit
-        if (end - ptr < 4) {
-          ESP_LOGV(TAG, "Out-of-bounds Fixed32-bit at offset %ld", (long) (ptr - buffer));
-          return;
-        }
-        uint32_t val;
-#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
-        // Protobuf fixed32 is little-endian — direct load on LE platforms
-        memcpy(&val, ptr, 4);
-#else
-        val = encode_uint32(ptr[3], ptr[2], ptr[1], ptr[0]);
-#endif
-        if (!this->decode_32bit(field_id, Proto32Bit(val))) {
-          ESP_LOGV(TAG, "Cannot decode 32-bit field %" PRIu32 " with value %" PRIu32 "!", field_id, val);
-        }
-        ptr += 4;
-        break;
-      }
-      default:
-        ESP_LOGV(TAG, "Invalid field type %" PRIu32 " at offset %ld", field_type, (long) (ptr - buffer));
+    if (field_type == WIRE_TYPE_VARINT) [[likely]] {
+      if (!read_varint(scalar)) {
+        ESP_LOGV(TAG, "Invalid VarInt at offset %ld", (long) (ptr - buffer));
         return;
+      }
+    } else {
+      switch (field_type) {
+        case WIRE_TYPE_LENGTH_DELIMITED: {
+          proto_varint_value_t length_value;
+          if (!read_varint(length_value)) {
+            ESP_LOGV(TAG, "Invalid Length Delimited at offset %ld", (long) (ptr - buffer));
+            return;
+          }
+          uint32_t field_length = static_cast<uint32_t>(length_value);
+          if (field_length > static_cast<size_t>(end - ptr)) {
+            ESP_LOGV(TAG, "Out-of-bounds Length Delimited at offset %ld", (long) (ptr - buffer));
+            return;
+          }
+          data = ptr;
+          scalar = field_length;
+          ptr += field_length;
+          break;
+        }
+        case WIRE_TYPE_FIXED32: {
+          if (end - ptr < 4) {
+            ESP_LOGV(TAG, "Out-of-bounds Fixed32-bit at offset %ld", (long) (ptr - buffer));
+            return;
+          }
+          // Byte loads instead of memcpy: ESP-IDF passes -fno-builtin-memcpy, which made this a call
+          scalar = encode_uint32(ptr[3], ptr[2], ptr[1], ptr[0]);
+          ptr += 4;
+          break;
+        }
+        default:
+          ESP_LOGV(TAG, "Invalid field type %" PRIu32 " at offset %ld", field_type, (long) (ptr - buffer));
+          return;
+      }
     }
+    field(msg, tag, data, scalar);
   }
 }
 

esphome/components/api/proto.h

@@ -10,6 +10,7 @@
 
 #include <cassert>
 #include <cstring>
+#include <type_traits>
 #include <vector>
 
 #ifdef ESPHOME_LOG_HAS_VERY_VERBOSE
@@ -170,40 +171,43 @@ class ProtoVarInt {
 class ProtoMessage;
 class ProtoSize;
 
-class ProtoLengthDelimited {
+/// Case label for decode_field(): the wire tag of a field, so a field that arrives with another wire
+/// type matches no case.
+constexpr uint32_t proto_tag(uint32_t field_id, uint32_t wire_type) { return (field_id << 3) | wire_type; }
+
+/// One decoded field: the payload pointer and a scalar holding the varint or fixed32 value, or the
+/// length of a length-delimited field. The wire type in the tag says which applies; accessors do not check.
+class ProtoFieldValue {
  public:
-  explicit ProtoLengthDelimited(const uint8_t *value, size_t length) : value_(value), length_(length) {}
-  std::string as_string() const { return std::string(reinterpret_cast<const char *>(this->value_), this->length_); }
+  ProtoFieldValue(const uint8_t *data, proto_varint_value_t scalar) : data_(data), scalar_(scalar) {}
 
-  // Direct access to raw data without string allocation
-  const uint8_t *data() const { return this->value_; }
-  size_t size() const { return this->length_; }
+  proto_varint_value_t as_varint() const { return this->scalar_; }
+  // A bool is sent as 0 or 1, so the low word is enough and saves a second compare with 64 bit varints
+  bool as_bool() const { return static_cast<uint32_t>(this->scalar_) != 0; }
 
-  /// Decode the length-delimited data into a message instance.
+  // Length-delimited accessors
+  const uint8_t *data() const { return this->data_; }
+  size_t size() const { return static_cast<size_t>(this->scalar_); }
+  std::string as_string() const { return std::string(reinterpret_cast<const char *>(this->data_), this->size()); }
+  /// Decode the length-delimited payload into a message instance.
   /// Template preserves concrete type so decode() resolves statically.
-  template<typename T> void decode_to_message(T &msg) const;
+  template<typename T> void decode_to_message(T &msg) const { msg.decode(this->data_, this->size()); }
 
- protected:
-  const uint8_t *const value_;
-  const size_t length_;
-};
-
-class Proto32Bit {
- public:
-  explicit Proto32Bit(uint32_t value) : value_(value) {}
-  uint32_t as_fixed32() const { return this->value_; }
-  int32_t as_sfixed32() const { return static_cast<int32_t>(this->value_); }
+  // Fixed32 accessors
+  uint32_t as_fixed32() const { return static_cast<uint32_t>(this->scalar_); }
+  int32_t as_sfixed32() const { return static_cast<int32_t>(this->as_fixed32()); }
   float as_float() const {
     union {
       uint32_t raw;
       float value;
     } s{};
-    s.raw = this->value_;
+    s.raw = this->as_fixed32();
     return s.value;
   }
 
- protected:
-  const uint32_t value_;
+ private:
+  const uint8_t *data_;
+  proto_varint_value_t scalar_;
 };
 
 // NOTE: Proto64Bit class removed - wire type 1 (64-bit fixed) not supported
@@ -252,7 +256,7 @@ class ProtoWriteBuffer {
    *
    * Following https://protobuf.dev/programming-guides/encoding/#structure
    */
-  void encode_field_raw(uint32_t field_id, uint32_t type) { this->encode_varint_raw((field_id << 3) | type); }
+  void encode_field_raw(uint32_t field_id, uint32_t type) { this->encode_varint_raw(proto_tag(field_id, type)); }
   /// Single-pass encode for repeated submessage elements.
   /// Thin template wrapper; all buffer work is in the non-template core.
   template<typename T> void encode_sub_message(uint32_t field_id, const T &value);
@@ -287,19 +291,31 @@ class ProtoWriteBuffer {
   uint8_t *pos_;
 };
 
+// A four byte unaligned store is a memcpy call on ESP-IDF (-fno-builtin-memcpy) and on ARM cores without
+// unaligned access (Cortex-M0+, ARM9), so those targets share one outlined byte store helper per fixed32
+// field. Elsewhere the write inlines to a single store, or on ESP8266 to a few stores that measured
+// faster than a call, so it stays inline.
+#if defined(USE_ESP32) || (defined(__arm__) && !defined(__ARM_FEATURE_UNALIGNED))
+#define PROTO_OUTLINE_FOR_SIZE __attribute__((noinline))
+#define PROTO_FIXED32_BYTE_STORES true
+#else
+#define PROTO_OUTLINE_FOR_SIZE inline
+#define PROTO_FIXED32_BYTE_STORES false
+#endif
+
 // Varint encoding thresholds — used by both proto_encode_* free functions and ProtoSize.
 constexpr uint32_t VARINT_MAX_1_BYTE = 1 << 7;   // 128
 constexpr uint32_t VARINT_MAX_2_BYTE = 1 << 14;  // 16384
 
-/// Static encode helpers for generated encode() functions.
-/// Generated code hoists buffer.pos_ into a local uint8_t *__restrict__ pos,
-/// then calls these methods which take pos by reference. No struct, no overhead.
-/// For sub-messages, pos is synced back to buffer before the call and reloaded after.
+/// Static encode helpers for the generated encode bodies. Each takes the write cursor by value and
+/// returns it advanced, so outlined calls at -Os chain through the return register instead of a
+/// stack slot. Helpers without a _force suffix skip fields holding the proto3 default.
 class ProtoEncode {
  public:
   /// Write a multi-byte varint directly through a pos pointer.
   template<typename T>
-  static inline void encode_varint_raw_loop(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM, T value) {
+  [[nodiscard]] static inline uint8_t *encode_varint_raw_loop(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                              T value) {
     do {
       PROTO_ENCODE_CHECK_BOUNDS(pos, 1);
       *pos++ = static_cast<uint8_t>(value | 0x80);
@@ -307,48 +323,49 @@ class ProtoEncode {
     } while (value > 0x7F);
     PROTO_ENCODE_CHECK_BOUNDS(pos, 1);
     *pos++ = static_cast<uint8_t>(value);
+    return pos;
   }
-  static inline void ESPHOME_ALWAYS_INLINE encode_varint_raw(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM,
-                                                             uint32_t value) {
+  [[nodiscard]] static inline uint8_t *ESPHOME_ALWAYS_INLINE
+  encode_varint_raw(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM, uint32_t value) {
     if (value < VARINT_MAX_1_BYTE) [[likely]] {
       PROTO_ENCODE_CHECK_BOUNDS(pos, 1);
       *pos++ = static_cast<uint8_t>(value);
-      return;
+      return pos;
     }
-    encode_varint_raw_loop(pos PROTO_ENCODE_DEBUG_ARG, value);
+    return encode_varint_raw_loop(pos PROTO_ENCODE_DEBUG_ARG, value);
   }
   /// Encode a varint that is expected to be 1-2 bytes (e.g. zigzag RSSI, small lengths).
-  static inline void ESPHOME_ALWAYS_INLINE encode_varint_raw_short(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM,
-                                                                   uint32_t value) {
+  [[nodiscard]] static inline uint8_t *ESPHOME_ALWAYS_INLINE
+  encode_varint_raw_short(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM, uint32_t value) {
     if (value < VARINT_MAX_1_BYTE) [[likely]] {
       PROTO_ENCODE_CHECK_BOUNDS(pos, 1);
       *pos++ = static_cast<uint8_t>(value);
-      return;
+      return pos;
     }
     if (value < VARINT_MAX_2_BYTE) [[likely]] {
       PROTO_ENCODE_CHECK_BOUNDS(pos, 2);
       *pos++ = static_cast<uint8_t>(value | 0x80);
       *pos++ = static_cast<uint8_t>(value >> 7);
-      return;
+      return pos;
     }
-    encode_varint_raw_loop(pos PROTO_ENCODE_DEBUG_ARG, value);
+    return encode_varint_raw_loop(pos PROTO_ENCODE_DEBUG_ARG, value);
   }
-  static inline void ESPHOME_ALWAYS_INLINE encode_varint_raw_64(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM,
-                                                                uint64_t value) {
+  [[nodiscard]] static inline uint8_t *ESPHOME_ALWAYS_INLINE
+  encode_varint_raw_64(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM, uint64_t value) {
     if (value < VARINT_MAX_1_BYTE) [[likely]] {
       PROTO_ENCODE_CHECK_BOUNDS(pos, 1);
       *pos++ = static_cast<uint8_t>(value);
-      return;
+      return pos;
     }
-    encode_varint_raw_loop(pos PROTO_ENCODE_DEBUG_ARG, value);
+    return encode_varint_raw_loop(pos PROTO_ENCODE_DEBUG_ARG, value);
   }
   /// Encode a 48-bit MAC address (stored in a uint64) as varint.
   /// Real MAC addresses occupy the full 48 bits (OUI in upper 24), so the
   /// fast path -- any non-zero bit in the top 6 of 48 -- emits exactly 7 bytes
   /// with no per-byte branch. Falls back to the general loop otherwise.
   /// Caller must guarantee value fits in 48 bits (checked in debug builds).
-  static inline void ESPHOME_ALWAYS_INLINE encode_varint_raw_48bit(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM,
-                                                                   uint64_t value) {
+  [[nodiscard]] static inline uint8_t *ESPHOME_ALWAYS_INLINE
+  encode_varint_raw_48bit(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM, uint64_t value) {
 #ifdef ESPHOME_DEBUG_API
     assert(value < (1ULL << (MAC_ADDRESS_SIZE * 8)) && "encode_varint_raw_48bit: value exceeds 48 bits");
 #endif
@@ -363,38 +380,39 @@ class ProtoEncode {
       pos[4] = static_cast<uint8_t>((value >> 28) | 0x80);
       pos[5] = static_cast<uint8_t>((value >> 35) | 0x80);
       pos[6] = static_cast<uint8_t>(value >> 42);
-      pos += 7;
-      return;
+      return pos + 7;
     }
-    encode_varint_raw_64(pos PROTO_ENCODE_DEBUG_ARG, value);
+    return encode_varint_raw_64(pos PROTO_ENCODE_DEBUG_ARG, value);
   }
-  static inline void ESPHOME_ALWAYS_INLINE encode_field_raw(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM,
-                                                            uint32_t field_id, uint32_t type) {
-    encode_varint_raw(pos PROTO_ENCODE_DEBUG_ARG, (field_id << 3) | type);
+  [[nodiscard]] static inline uint8_t *ESPHOME_ALWAYS_INLINE
+  encode_field_raw(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM, uint32_t field_id, uint32_t type) {
+    return encode_varint_raw(pos PROTO_ENCODE_DEBUG_ARG, proto_tag(field_id, type));
   }
   /// Write a single precomputed tag byte. Tag must be < 128.
-  static inline void ESPHOME_ALWAYS_INLINE write_raw_byte(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM,
-                                                          uint8_t b) {
+  [[nodiscard]] static inline uint8_t *ESPHOME_ALWAYS_INLINE
+  write_raw_byte(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM, uint8_t b) {
     PROTO_ENCODE_CHECK_BOUNDS(pos, 1);
     *pos++ = b;
+    return pos;
   }
   /// Reserve one byte for later backpatch (e.g., sub-message length).
   /// Advances pos past the reserved byte without writing a value.
-  static inline void ESPHOME_ALWAYS_INLINE reserve_byte(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM) {
+  [[nodiscard]] static inline uint8_t *ESPHOME_ALWAYS_INLINE
+  reserve_byte(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM) {
     PROTO_ENCODE_CHECK_BOUNDS(pos, 1);
-    pos++;
+    return pos + 1;
   }
   /// Write raw bytes to the buffer (no tag, no length prefix).
-  static inline void ESPHOME_ALWAYS_INLINE encode_raw(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM,
-                                                      const void *data, size_t len) {
+  [[nodiscard]] static inline uint8_t *ESPHOME_ALWAYS_INLINE
+  encode_raw(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM, const void *data, size_t len) {
     PROTO_ENCODE_CHECK_BOUNDS(pos, len);
     std::memcpy(pos, data, len);
-    pos += len;
+    return pos + len;
   }
   /// Encode tag + 1-byte length + raw string data. For strings with max_data_length < 128.
   /// Tag must be a single-byte varint (< 128). Always encodes (no zero check).
-  static inline void encode_short_string_force(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM, uint8_t tag,
-                                               const StringRef &ref) {
+  [[nodiscard]] static inline uint8_t *encode_short_string_force(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                                 uint8_t tag, const StringRef &ref) {
 #ifdef ESPHOME_DEBUG_API
     assert(ref.size() < 128 && "encode_short_string_force: string exceeds max_data_length < 128");
 #endif
@@ -402,137 +420,191 @@ class ProtoEncode {
     pos[0] = tag;
     pos[1] = static_cast<uint8_t>(ref.size());
     std::memcpy(pos + 2, ref.c_str(), ref.size());
-    pos += 2 + ref.size();
+    return pos + 2 + ref.size();
   }
-  /// Write a precomputed tag byte + 32-bit value in one operation.
-  static inline void ESPHOME_ALWAYS_INLINE write_tag_and_fixed32(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM,
-                                                                 uint8_t tag, uint32_t value) {
+  /// Write a precomputed tag byte + 32-bit value. Outlined on embedded: one copy beats inline stores per field.
+  [[nodiscard]] static PROTO_OUTLINE_FOR_SIZE uint8_t *write_tag_and_fixed32(
+      uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM, uint8_t tag, uint32_t value) {
     PROTO_ENCODE_CHECK_BOUNDS(pos, 5);
     pos[0] = tag;
-#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
-    std::memcpy(pos + 1, &value, 4);
-#else
-    pos[1] = static_cast<uint8_t>(value & 0xFF);
-    pos[2] = static_cast<uint8_t>((value >> 8) & 0xFF);
-    pos[3] = static_cast<uint8_t>((value >> 16) & 0xFF);
-    pos[4] = static_cast<uint8_t>((value >> 24) & 0xFF);
-#endif
-    pos += 5;
+    write_fixed32_le(pos + 1, value);
+    return pos + 5;
   }
-  static inline void encode_string(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM, uint32_t field_id,
-                                   const char *string, size_t len, bool force = false) {
-    if (len == 0 && !force)
-      return;
-    encode_field_raw(pos PROTO_ENCODE_DEBUG_ARG, field_id, 2);  // type 2: Length-delimited string
+  [[nodiscard]] static inline uint8_t *encode_string_force(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                           uint32_t field_id, const char *string, size_t len) {
+    pos = encode_field_raw(pos PROTO_ENCODE_DEBUG_ARG, field_id, 2);  // type 2: Length-delimited string
     // NOLINTNEXTLINE(readability-inconsistent-ifelse-braces) -- false positive on [[likely]] attribute
     if (len < VARINT_MAX_1_BYTE) [[likely]] {
       PROTO_ENCODE_CHECK_BOUNDS(pos, 1 + len);
       *pos++ = static_cast<uint8_t>(len);
     } else {
-      encode_varint_raw_loop(pos PROTO_ENCODE_DEBUG_ARG, len);
+      pos = encode_varint_raw_loop(pos PROTO_ENCODE_DEBUG_ARG, len);
       PROTO_ENCODE_CHECK_BOUNDS(pos, len);
     }
     std::memcpy(pos, string, len);
-    pos += len;
+    return pos + len;
   }
-  static inline void encode_string(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM, uint32_t field_id,
-                                   const std::string &value, bool force = false) {
-    encode_string(pos PROTO_ENCODE_DEBUG_ARG, field_id, value.data(), value.size(), force);
+  [[nodiscard]] static inline uint8_t *encode_string(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                     uint32_t field_id, const char *string, size_t len) {
+    if (len == 0)
+      return pos;
+    return encode_string_force(pos PROTO_ENCODE_DEBUG_ARG, field_id, string, len);
   }
-  static inline void encode_string(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM, uint32_t field_id,
-                                   const StringRef &ref, bool force = false) {
-    encode_string(pos PROTO_ENCODE_DEBUG_ARG, field_id, ref.c_str(), ref.size(), force);
+  [[nodiscard]] static inline uint8_t *encode_string_force(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                           uint32_t field_id, const std::string &value) {
+    return encode_string_force(pos PROTO_ENCODE_DEBUG_ARG, field_id, value.data(), value.size());
   }
-  static inline void encode_bytes(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM, uint32_t field_id,
-                                  const uint8_t *data, size_t len, bool force = false) {
-    encode_string(pos PROTO_ENCODE_DEBUG_ARG, field_id, reinterpret_cast<const char *>(data), len, force);
+  [[nodiscard]] static inline uint8_t *encode_string(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                     uint32_t field_id, const StringRef &ref) {
+    return encode_string(pos PROTO_ENCODE_DEBUG_ARG, field_id, ref.c_str(), ref.size());
   }
-  static inline void encode_uint32(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM, uint32_t field_id,
-                                   uint32_t value, bool force = false) {
-    if (value == 0 && !force)
-      return;
-    encode_field_raw(pos PROTO_ENCODE_DEBUG_ARG, field_id, 0);
-    encode_varint_raw(pos PROTO_ENCODE_DEBUG_ARG, value);
+  [[nodiscard]] static inline uint8_t *encode_string_force(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                           uint32_t field_id, const StringRef &ref) {
+    return encode_string_force(pos PROTO_ENCODE_DEBUG_ARG, field_id, ref.c_str(), ref.size());
   }
-  static inline void encode_uint64(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM, uint32_t field_id,
-                                   uint64_t value, bool force = false) {
-    if (value == 0 && !force)
-      return;
-    encode_field_raw(pos PROTO_ENCODE_DEBUG_ARG, field_id, 0);
-    encode_varint_raw_64(pos PROTO_ENCODE_DEBUG_ARG, value);
+  [[nodiscard]] static inline uint8_t *encode_bytes(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                    uint32_t field_id, const uint8_t *data, size_t len) {
+    return encode_string(pos PROTO_ENCODE_DEBUG_ARG, field_id, reinterpret_cast<const char *>(data), len);
   }
-  static inline void encode_bool(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM, uint32_t field_id, bool value,
-                                 bool force = false) {
-    if (!value && !force)
-      return;
-    encode_field_raw(pos PROTO_ENCODE_DEBUG_ARG, field_id, 0);
+  [[nodiscard]] static inline uint8_t *encode_bytes_force(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                          uint32_t field_id, const uint8_t *data, size_t len) {
+    return encode_string_force(pos PROTO_ENCODE_DEBUG_ARG, field_id, reinterpret_cast<const char *>(data), len);
+  }
+  [[nodiscard]] static inline uint8_t *encode_uint32_force(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                           uint32_t field_id, uint32_t value) {
+    pos = encode_field_raw(pos PROTO_ENCODE_DEBUG_ARG, field_id, 0);
+    return encode_varint_raw(pos PROTO_ENCODE_DEBUG_ARG, value);
+  }
+  [[nodiscard]] static inline uint8_t *encode_uint32(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                     uint32_t field_id, uint32_t value) {
+    if (value == 0)
+      return pos;
+    return encode_uint32_force(pos PROTO_ENCODE_DEBUG_ARG, field_id, value);
+  }
+  [[nodiscard]] static inline uint8_t *encode_uint64_force(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                           uint32_t field_id, uint64_t value) {
+    pos = encode_field_raw(pos PROTO_ENCODE_DEBUG_ARG, field_id, 0);
+    return encode_varint_raw_64(pos PROTO_ENCODE_DEBUG_ARG, value);
+  }
+  [[nodiscard]] static inline uint8_t *encode_uint64(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                     uint32_t field_id, uint64_t value) {
+    if (value == 0)
+      return pos;
+    return encode_uint64_force(pos PROTO_ENCODE_DEBUG_ARG, field_id, value);
+  }
+  [[nodiscard]] static inline uint8_t *encode_bool_force(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                         uint32_t field_id, bool value) {
+    pos = encode_field_raw(pos PROTO_ENCODE_DEBUG_ARG, field_id, 0);
     PROTO_ENCODE_CHECK_BOUNDS(pos, 1);
     *pos++ = value ? 0x01 : 0x00;
+    return pos;
   }
-  static inline void encode_fixed32(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM, uint32_t field_id,
-                                    uint32_t value, bool force = false) {
-    if (value == 0 && !force)
-      return;
-    encode_field_raw(pos PROTO_ENCODE_DEBUG_ARG, field_id, 5);
+  [[nodiscard]] static inline uint8_t *encode_bool(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                   uint32_t field_id, bool value) {
+    if (!value)
+      return pos;
+    return encode_bool_force(pos PROTO_ENCODE_DEBUG_ARG, field_id, value);
+  }
+  /// Tag + fixed32 for multi-byte tags; single-byte tags use write_tag_and_fixed32.
+  [[nodiscard]] static PROTO_OUTLINE_FOR_SIZE uint8_t *encode_fixed32_force(
+      uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM, uint32_t field_id, uint32_t value) {
+    pos = encode_field_raw(pos PROTO_ENCODE_DEBUG_ARG, field_id, 5);
     PROTO_ENCODE_CHECK_BOUNDS(pos, 4);
-#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
-    std::memcpy(pos, &value, 4);
-    pos += 4;
-#else
-    *pos++ = (value >> 0) & 0xFF;
-    *pos++ = (value >> 8) & 0xFF;
-    *pos++ = (value >> 16) & 0xFF;
-    *pos++ = (value >> 24) & 0xFF;
-#endif
+    write_fixed32_le(pos, value);
+    return pos + 4;
+  }
+  [[nodiscard]] static inline uint8_t *encode_fixed32(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                      uint32_t field_id, uint32_t value) {
+    if (value == 0)
+      return pos;
+    return encode_fixed32_force(pos PROTO_ENCODE_DEBUG_ARG, field_id, value);
   }
   // NOTE: Wire type 1 (64-bit fixed: double, fixed64, sfixed64) is intentionally
   // not supported to reduce overhead on embedded systems. All ESPHome devices are
   // 32-bit microcontrollers where 64-bit operations are expensive. If 64-bit support
   // is needed in the future, the necessary encoding/decoding functions must be added.
-  static inline void encode_float(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM, uint32_t field_id, float value,
-                                  bool force = false) {
-    uint32_t raw = float_to_raw(value);
-    if (raw == 0 && !force)
-      return;
-    encode_fixed32(pos PROTO_ENCODE_DEBUG_ARG, field_id, raw);
+  [[nodiscard]] static inline uint8_t *encode_float(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                    uint32_t field_id, float value) {
+    return encode_fixed32(pos PROTO_ENCODE_DEBUG_ARG, field_id, float_to_raw(value));
   }
-  static inline void encode_int32(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM, uint32_t field_id, int32_t value,
-                                  bool force = false) {
+  [[nodiscard]] static inline uint8_t *encode_float_force(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                          uint32_t field_id, float value) {
+    return encode_fixed32_force(pos PROTO_ENCODE_DEBUG_ARG, field_id, float_to_raw(value));
+  }
+  [[nodiscard]] static inline uint8_t *encode_int32_force(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                          uint32_t field_id, int32_t value) {
     if (value < 0) {
       // negative int32 is always 10 byte long
-      encode_uint64(pos PROTO_ENCODE_DEBUG_ARG, field_id, static_cast<uint64_t>(value), force);
-      return;
+      return encode_uint64_force(pos PROTO_ENCODE_DEBUG_ARG, field_id, static_cast<uint64_t>(value));
     }
-    encode_uint32(pos PROTO_ENCODE_DEBUG_ARG, field_id, static_cast<uint32_t>(value), force);
+    return encode_uint32_force(pos PROTO_ENCODE_DEBUG_ARG, field_id, static_cast<uint32_t>(value));
   }
-  static inline void encode_int64(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM, uint32_t field_id, int64_t value,
-                                  bool force = false) {
-    encode_uint64(pos PROTO_ENCODE_DEBUG_ARG, field_id, static_cast<uint64_t>(value), force);
+  [[nodiscard]] static inline uint8_t *encode_int32(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                    uint32_t field_id, int32_t value) {
+    if (value == 0)
+      return pos;
+    return encode_int32_force(pos PROTO_ENCODE_DEBUG_ARG, field_id, value);
   }
-  static inline void encode_sint32(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM, uint32_t field_id,
-                                   int32_t value, bool force = false) {
-    encode_uint32(pos PROTO_ENCODE_DEBUG_ARG, field_id, encode_zigzag32(value), force);
+  [[nodiscard]] static inline uint8_t *encode_int64(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                    uint32_t field_id, int64_t value) {
+    return encode_uint64(pos PROTO_ENCODE_DEBUG_ARG, field_id, static_cast<uint64_t>(value));
   }
-  static inline void encode_sint64(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM, uint32_t field_id,
-                                   int64_t value, bool force = false) {
-    encode_uint64(pos PROTO_ENCODE_DEBUG_ARG, field_id, encode_zigzag64(value), force);
+  [[nodiscard]] static inline uint8_t *encode_int64_force(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                          uint32_t field_id, int64_t value) {
+    return encode_uint64_force(pos PROTO_ENCODE_DEBUG_ARG, field_id, static_cast<uint64_t>(value));
   }
-  /// Sub-message encoding: sync pos to buffer, delegate, get pos from return value.
+  [[nodiscard]] static inline uint8_t *encode_sint32(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                     uint32_t field_id, int32_t value) {
+    return encode_uint32(pos PROTO_ENCODE_DEBUG_ARG, field_id, encode_zigzag32(value));
+  }
+  [[nodiscard]] static inline uint8_t *encode_sint32_force(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                           uint32_t field_id, int32_t value) {
+    return encode_uint32_force(pos PROTO_ENCODE_DEBUG_ARG, field_id, encode_zigzag32(value));
+  }
+  [[nodiscard]] static inline uint8_t *encode_sint64(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                     uint32_t field_id, int64_t value) {
+    return encode_uint64(pos PROTO_ENCODE_DEBUG_ARG, field_id, encode_zigzag64(value));
+  }
+  [[nodiscard]] static inline uint8_t *encode_sint64_force(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                           uint32_t field_id, int64_t value) {
+    return encode_uint64_force(pos PROTO_ENCODE_DEBUG_ARG, field_id, encode_zigzag64(value));
+  }
+  /// Sub-message encoding: sync pos to buffer, delegate, read the cursor back.
   template<typename T>
-  static inline void encode_sub_message(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM, ProtoWriteBuffer &buffer,
-                                        uint32_t field_id, const T &value) {
+  [[nodiscard]] static inline uint8_t *encode_sub_message(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                          ProtoWriteBuffer &buffer, uint32_t field_id, const T &value) {
     buffer.set_pos(pos);
     buffer.encode_sub_message(field_id, value);
-    pos = buffer.get_pos();
+    return buffer.get_pos();
   }
   template<typename T>
-  static inline void encode_optional_sub_message(uint8_t *__restrict__ &pos PROTO_ENCODE_DEBUG_PARAM,
-                                                 ProtoWriteBuffer &buffer, uint32_t field_id, const T &value) {
+  [[nodiscard]] static inline uint8_t *encode_optional_sub_message(uint8_t *__restrict__ pos PROTO_ENCODE_DEBUG_PARAM,
+                                                                   ProtoWriteBuffer &buffer, uint32_t field_id,
+                                                                   const T &value) {
     buffer.set_pos(pos);
     buffer.encode_optional_sub_message(field_id, value);
-    pos = buffer.get_pos();
+    return buffer.get_pos();
+  }
+
+ private:
+  /// Unaligned little endian store of four bytes: byte stores where the outlined helper lives (ESP-IDF, ARM
+  /// without unaligned access), otherwise a memcpy the compiler folds into one store. Callers bounds check
+  /// and advance the cursor themselves.
+  static inline void ESPHOME_ALWAYS_INLINE write_fixed32_le(uint8_t *__restrict__ pos, uint32_t value) {
+    if constexpr (PROTO_FIXED32_BYTE_STORES) {
+      // Spelled out so the outlined helper does not itself become a memcpy call
+      pos[0] = static_cast<uint8_t>(value);
+      pos[1] = static_cast<uint8_t>(value >> 8);
+      pos[2] = static_cast<uint8_t>(value >> 16);
+      pos[3] = static_cast<uint8_t>(value >> 24);
+    } else {
+      const uint32_t le = convert_little_endian(value);
+      __builtin_memcpy(pos, &le, 4);
+    }
   }
 };
+#undef PROTO_OUTLINE_FOR_SIZE
+#undef PROTO_FIXED32_BYTE_STORES
 
 #ifdef HAS_PROTO_MESSAGE_DUMP
 /**
@@ -624,11 +696,12 @@ class DumpBuffer {
 
 class ProtoMessage {
  public:
-  // Non-virtual defaults for messages with no fields.
-  // Concrete message classes hide these with their own implementations.
-  // All call sites use templates to preserve the concrete type, so virtual
-  // dispatch is not needed. This eliminates per-message vtable entries for
-  // encode/calculate_size, saving ~1.3 KB of flash across all message types.
+  // Non-virtual defaults for messages with no fields; generated classes hide all four. The
+  // static encode_msg/calc_size_msg take const void * so &T::encode_msg needs no thunk.
+  static uint8_t *encode_msg(const void *self, ProtoWriteBuffer &buffer PROTO_ENCODE_DEBUG_PARAM) {
+    return buffer.get_pos();
+  }
+  static uint32_t calc_size_msg(const void *self) { return 0; }
   uint8_t *encode(ProtoWriteBuffer &buffer PROTO_ENCODE_DEBUG_PARAM) const { return buffer.get_pos(); }
   uint32_t calculate_size() const { return 0; }
 #ifdef HAS_PROTO_MESSAGE_DUMP
@@ -648,7 +721,13 @@ class ProtoMessage {
 // Base class for messages that support decoding
 class ProtoDecodableMessage : public ProtoMessage {
  public:
-  void decode(const uint8_t *buffer, size_t length);
+  /// Stores one decoded field into \p msg; generated per message type. \p scalar is the varint or
+  /// fixed32 value, or the length of the length-delimited payload at \p data. An unknown field or
+  /// wrong wire type matches no case and is skipped.
+  using DecodeFieldFn = void (*)(void *msg, uint32_t tag, const uint8_t *data, proto_varint_value_t scalar);
+  /// Walk \p buffer and hand every field to \p field. The generated decode() passes the message's
+  /// own decode_field, so decodable messages carry no vtable.
+  static void decode_fields(void *msg, const uint8_t *buffer, size_t length, DecodeFieldFn field);
 
   /**
    * Count occurrences of a repeated field in a protobuf buffer.
@@ -660,14 +739,15 @@ class ProtoDecodableMessage : public ProtoMessage {
    * @return Number of times the field appears in the buffer
    */
   static uint32_t count_repeated_field(const uint8_t *buffer, size_t length, uint32_t target_field_id);
-
- protected:
-  ~ProtoDecodableMessage() = default;
-  virtual bool decode_varint(uint32_t field_id, proto_varint_value_t value) { return false; }
-  virtual bool decode_length(uint32_t field_id, ProtoLengthDelimited value) { return false; }
-  virtual bool decode_32bit(uint32_t field_id, Proto32Bit value) { return false; }
-  // NOTE: decode_64bit removed - wire type 1 not supported
+  // The destructor stays accessible on purpose: the generated messages are aggregates that brace
+  // initialise sub message members, which copies a base temporary. That trades away the compile time
+  // guard against deleting through this type; messages are stack locals and never owned through a base
+  // pointer. ProtoMessage keeps its guard for the dump builds.
 };
+#ifndef HAS_PROTO_MESSAGE_DUMP
+// decode() passes decode_field explicitly, so nothing here may add a vtable
+static_assert(!std::is_polymorphic_v<ProtoDecodableMessage>, "decodable messages carry no vtable");
+#endif
 
 class ProtoSize {
  public:
@@ -792,7 +872,7 @@ class ProtoSize {
    * @return The number of bytes needed to encode the field ID and wire type
    */
   static constexpr uint32_t field(uint32_t field_id, uint32_t type) {
-    uint32_t tag = (field_id << 3) | (type & WIRE_TYPE_MASK);
+    uint32_t tag = proto_tag(field_id, type & WIRE_TYPE_MASK);
     return varint(tag);
   }
 
@@ -876,24 +956,14 @@ class ProtoSize {
 
 // Implementation of methods that depend on ProtoSize being fully defined
 
-// Encode thunk — converts void* back to concrete type for direct encode() call
-template<typename T> uint8_t *proto_encode_msg(const void *msg, ProtoWriteBuffer &buf PROTO_ENCODE_DEBUG_PARAM) {
-  return static_cast<const T *>(msg)->encode(buf PROTO_ENCODE_DEBUG_ARG);
-}
-
 // Thin template wrapper; delegates to non-template core in proto.cpp.
 template<typename T> inline void ProtoWriteBuffer::encode_sub_message(uint32_t field_id, const T &value) {
-  this->encode_sub_message(field_id, &value, &proto_encode_msg<T>);
+  this->encode_sub_message(field_id, &value, &T::encode_msg);
 }
 
 // Thin template wrapper; delegates to non-template core.
 template<typename T> inline void ProtoWriteBuffer::encode_optional_sub_message(uint32_t field_id, const T &value) {
-  this->encode_optional_sub_message(field_id, value.calculate_size(), &value, &proto_encode_msg<T>);
-}
-
-// Template decode_to_message - preserves concrete type so decode() resolves statically
-template<typename T> void ProtoLengthDelimited::decode_to_message(T &msg) const {
-  msg.decode(this->value_, this->length_);
+  this->encode_optional_sub_message(field_id, T::calc_size_msg(&value), &value, &T::encode_msg);
 }
 
 template<typename T> const char *proto_enum_to_string(T value);

esphome/components/coolix/climate.py

@@ -1,5 +1,5 @@
 import esphome.codegen as cg
-from esphome.components import climate_ir, remote_base
+from esphome.components import climate_ir
 from esphome.types import ConfigType
 
 AUTO_LOAD = ["climate_ir"]
@@ -12,5 +12,4 @@ CONFIG_SCHEMA = climate_ir.climate_ir_with_receiver_schema(CoolixClimate)
 
 
 async def to_code(config: ConfigType) -> None:
-    remote_base.request_protocol("coolix")  # used from C++
     await climate_ir.new_climate_ir(config)

esphome/components/infrared/infrared.cpp

@@ -59,6 +59,11 @@ void Infrared::setup() {
   // Set up traits based on configuration
   this->traits_.set_supports_transmitter(this->has_transmitter());
   this->traits_.set_supports_receiver(this->has_receiver());
+
+  // Register as listener for received IR data
+  if (this->receiver_ != nullptr) {
+    this->receiver_->register_listener(this);
+  }
 }
 
 void Infrared::dump_config() {

esphome/components/ir_rf_proxy/__init__.py

@@ -1,9 +1,6 @@
 """IR/RF Proxy component - provides remote_base backend for infrared platform."""
 
 import esphome.codegen as cg
-from esphome.components import remote_base
-from esphome.cpp_generator import MockObj
-from esphome.types import ConfigType
 
 CODEOWNERS = ["@kbx81"]
 
@@ -12,10 +9,3 @@ ir_rf_proxy_ns = cg.esphome_ns.namespace("ir_rf_proxy")
 
 CONF_REMOTE_RECEIVER_ID = "remote_receiver_id"
 CONF_REMOTE_TRANSMITTER_ID = "remote_transmitter_id"
-
-
-async def attach_receiver(var: MockObj, config: ConfigType) -> None:
-    """Wire the configured remote_receiver to a proxy entity and register it as a listener."""
-    receiver = await cg.get_variable(config[CONF_REMOTE_RECEIVER_ID])
-    cg.add(var.set_receiver(receiver))
-    remote_base.add_listener(receiver, var)

esphome/components/ir_rf_proxy/infrared.py

@@ -9,12 +9,7 @@ import esphome.config_validation as cv
 from esphome.const import CONF_CARRIER_DUTY_PERCENT, CONF_FREQUENCY
 import esphome.final_validate as fv
 
-from . import (
-    CONF_REMOTE_RECEIVER_ID,
-    CONF_REMOTE_TRANSMITTER_ID,
-    attach_receiver,
-    ir_rf_proxy_ns,
-)
+from . import CONF_REMOTE_RECEIVER_ID, CONF_REMOTE_TRANSMITTER_ID, ir_rf_proxy_ns
 
 CODEOWNERS = ["@kbx81"]
 DEPENDENCIES = ["infrared"]
@@ -87,7 +82,8 @@ async def to_code(config: dict[str, Any]) -> None:
 
     # Link receiver if specified
     if CONF_REMOTE_RECEIVER_ID in config:
-        await attach_receiver(var, config)
+        receiver = await cg.get_variable(config[CONF_REMOTE_RECEIVER_ID])
+        cg.add(var.set_receiver(receiver))
 
     # Set receiver demodulation frequency if specified (metadata only, no hardware effect)
     if CONF_RECEIVER_FREQUENCY in config:

esphome/components/ir_rf_proxy/ir_rf_proxy.cpp

@@ -97,6 +97,10 @@ void RfProxy::setup() {
 
   // remote_transmitter/receiver always uses OOK (on-off keying)
   this->traits_.add_supported_modulation(radio_frequency::RadioFrequencyModulation::RADIO_FREQUENCY_MODULATION_OOK);
+
+  if (this->receiver_ != nullptr) {
+    this->receiver_->register_listener(this);
+  }
 }
 
 void RfProxy::dump_config() {

esphome/components/ir_rf_proxy/radio_frequency.py

@@ -7,12 +7,7 @@ from esphome.const import CONF_CARRIER_DUTY_PERCENT, CONF_FREQUENCY
 import esphome.final_validate as fv
 from esphome.types import ConfigType
 
-from . import (
-    CONF_REMOTE_RECEIVER_ID,
-    CONF_REMOTE_TRANSMITTER_ID,
-    attach_receiver,
-    ir_rf_proxy_ns,
-)
+from . import CONF_REMOTE_RECEIVER_ID, CONF_REMOTE_TRANSMITTER_ID, ir_rf_proxy_ns
 
 CODEOWNERS = ["@kbx81"]
 DEPENDENCIES = ["radio_frequency"]
@@ -71,4 +66,5 @@ async def to_code(config: ConfigType) -> None:
         cg.add(var.set_transmitter(transmitter))
 
     if CONF_REMOTE_RECEIVER_ID in config:
-        await attach_receiver(var, config)
+        receiver = await cg.get_variable(config[CONF_REMOTE_RECEIVER_ID])
+        cg.add(var.set_receiver(receiver))

esphome/components/midea/climate.py

@@ -1,6 +1,6 @@
 from esphome import automation
 import esphome.codegen as cg
-from esphome.components import climate, remote_base, remote_transmitter, sensor, uart
+from esphome.components import climate, remote_transmitter, sensor, uart
 from esphome.components.climate import ClimateMode, ClimatePreset, ClimateSwingMode
 from esphome.components.remote_base import CONF_TRANSMITTER_ID
 import esphome.config_validation as cv
@@ -280,7 +280,6 @@ async def to_code(config):
     cg.add(var.set_response_timeout(config[CONF_TIMEOUT].total_milliseconds))
     cg.add(var.set_request_attempts(config[CONF_NUM_ATTEMPTS]))
     if CONF_TRANSMITTER_ID in config:
-        remote_base.request_protocol("midea")  # ir_transmitter.h uses it from C++
         cg.add_define("USE_REMOTE_TRANSMITTER")
         transmitter_ = await cg.get_variable(config[CONF_TRANSMITTER_ID])
         cg.add(var.set_transmitter(transmitter_))

esphome/components/midea_ir/climate.py

@@ -1,5 +1,5 @@
 import esphome.codegen as cg
-from esphome.components import climate_ir, remote_base
+from esphome.components import climate_ir
 import esphome.config_validation as cv
 from esphome.const import CONF_USE_FAHRENHEIT
 from esphome.types import ConfigType
@@ -19,9 +19,5 @@ CONFIG_SCHEMA = climate_ir.climate_ir_with_receiver_schema(MideaIR).extend(
 
 
 async def to_code(config: ConfigType) -> None:
-    # midea_ir uses MideaProtocol from C++ and auto-loads coolix, whose coolix.cpp uses
-    # CoolixProtocol even when no coolix climate is configured
-    remote_base.request_protocol("midea")
-    remote_base.request_protocol("coolix")
     var = await climate_ir.new_climate_ir(config)
     cg.add(var.set_fahrenheit(config[CONF_USE_FAHRENHEIT]))

esphome/components/remote_base/__init__.py

@@ -1,11 +1,6 @@
-from collections.abc import Callable
-from pathlib import Path
-from typing import Any
-
 from esphome import automation
 import esphome.codegen as cg
 from esphome.components import binary_sensor
-from esphome.config_helpers import filter_source_files_from_defines
 import esphome.config_validation as cv
 from esphome.const import (
     CONF_ADDRESS,
@@ -45,9 +40,7 @@ from esphome.const import (
     CONF_ZERO,
 )
 from esphome.core import ID, coroutine
-from esphome.cpp_generator import MockObj
 from esphome.schema_extractors import SCHEMA_EXTRACT, schema_extractor
-from esphome.types import ConfigType
 from esphome.util import Registry, SimpleRegistry
 
 AUTO_LOAD = ["binary_sensor"]
@@ -97,25 +90,9 @@ REMOTE_TRANSMITTABLE_SCHEMA = cv.Schema(
 )
 
 
-# Listener and dumper lists are StaticVectors sized from these counts, so every
-# registration must go through add_listener / add_dumper
-_request_listener_slot = cg.slot_counter("REMOTE_BASE_LISTENER_COUNT")
-_request_dumper_slot = cg.slot_counter("REMOTE_BASE_DUMPER_COUNT")
-
-
-def add_listener(receiver: MockObj, listener: MockObj) -> None:
-    _request_listener_slot()
-    cg.add(receiver.register_listener(listener))
-
-
-def add_dumper(receiver: MockObj, dumper: MockObj) -> None:
-    _request_dumper_slot()
-    cg.add(receiver.register_dumper(dumper))
-
-
-async def register_listener(var: MockObj, config: ConfigType) -> None:
+async def register_listener(var, config):
     receiver = await cg.get_variable(config[CONF_RECEIVER_ID])
-    add_listener(receiver, var)
+    cg.add(receiver.register_listener(var))
 
 
 async def register_transmittable(var, config):
@@ -123,47 +100,8 @@ async def register_transmittable(var, config):
     cg.add(var.set_transmitter(transmitter_))
 
 
-# Registry names that share a protocol source file
-def _protocol_stem(name: str) -> str:
-    if name.startswith("rc_switch"):
-        return "rc_switch"
-    if name == "canalsatld":
-        return "canalsat"
-    return name
-
-
-def protocol_define(name: str) -> str:
-    return f"USE_REMOTE_PROTOCOL_{_protocol_stem(name).upper()}"
-
-
-def request_protocol(name: str) -> None:
-    """Keep a protocol's source file in the build; components using it from C++ must call this."""
-    cg.add_define(protocol_define(name))
-
-
-_PROTOCOL_STEMS = sorted(
-    path.name.removesuffix("_protocol.cpp")
-    for path in Path(__file__).parent.glob("*_protocol.cpp")
-)
-# Only the protocol sources a configuration uses are compiled
-FILTER_SOURCE_FILES = filter_source_files_from_defines(
-    {f"{stem}_protocol.cpp": protocol_define(stem) for stem in _PROTOCOL_STEMS}
-)
-
-
-def register_binary_sensor(
-    name: str, type: MockObj, schema: cv.Schema | dict
-) -> Callable[[Callable[[MockObj, ConfigType], Any]], Callable]:
-    registerer = BINARY_SENSOR_REGISTRY.register(name, type, schema)
-
-    def decorator(func: Callable[[MockObj, ConfigType], Any]) -> Callable:
-        async def new_func(var: MockObj, config: ConfigType) -> None:
-            request_protocol(name)
-            await coroutine(func)(var, config)
-
-        return registerer(new_func)
-
-    return decorator
+def register_binary_sensor(name, type, schema):
+    return BINARY_SENSOR_REGISTRY.register(name, type, schema)
 
 
 def register_trigger(name, type, data_type):
@@ -176,7 +114,6 @@ def register_trigger(name, type, data_type):
 
     def decorator(func):
         async def new_func(config):
-            request_protocol(name)
             var = cg.new_Pvariable(config[CONF_TRIGGER_ID])
             await coroutine(func)(var, config)
             await automation.build_automation(var, [(data_type, "x")], config)
@@ -194,7 +131,6 @@ def register_dumper(name, type, schema=None):
 
     def decorator(func):
         async def new_func(config, dumper_id):
-            request_protocol(name)
             var = cg.new_Pvariable(dumper_id)
             await coroutine(func)(var, config)
             return var
@@ -235,7 +171,6 @@ def register_action(name, type_, schema):
 
     def decorator(func):
         async def new_func(config, action_id, template_arg, args):
-            request_protocol(name)
             var = cg.new_Pvariable(action_id, template_arg)
             await register_transmittable(var, config)
             if CONF_REPEAT in config:
@@ -275,21 +210,9 @@ TRIGGER_REGISTRY = SimpleRegistry()
 DUMPER_REGISTRY = Registry()
 
 
-def _dumper_key(item: Any) -> Any:
-    """Registry key of a dump entry in either its string or its mapping form."""
-    if isinstance(item, dict) and len(item) == 1:
-        return next(iter(item))
-    return item
-
-
 def validate_dumpers(value):
     if isinstance(value, str) and value.lower() == "all":
         return validate_dumpers(list(DUMPER_REGISTRY.keys()))
-    if isinstance(value, list):
-        # a dumper listed twice would register twice; the receiver holds one secondary dumper
-        keys = [_dumper_key(item) for item in value]
-        if all(isinstance(key, str) for key in keys):
-            value = list(dict(zip(keys, value, strict=True)).values())
     return cv.validate_registry("dumper", DUMPER_REGISTRY)(value)
 
 

esphome/components/remote_base/abbwelcome_protocol.h

@@ -191,9 +191,9 @@ class ABBWelcomeData {
 
 class ABBWelcomeProtocol : public RemoteProtocol<ABBWelcomeData> {
  public:
-  void encode(RemoteTransmitData *dst, const ABBWelcomeData &src);
-  optional<ABBWelcomeData> decode(RemoteReceiveData src);
-  void dump(const ABBWelcomeData &data);
+  void encode(RemoteTransmitData *dst, const ABBWelcomeData &src) override;
+  optional<ABBWelcomeData> decode(RemoteReceiveData src) override;
+  void dump(const ABBWelcomeData &data) override;
 
  protected:
   void encode_byte_(RemoteTransmitData *dst, uint8_t data) const;

esphome/components/remote_base/aeha_protocol.h

@@ -15,9 +15,9 @@ struct AEHAData {
 
 class AEHAProtocol : public RemoteProtocol<AEHAData> {
  public:
-  void encode(RemoteTransmitData *dst, const AEHAData &data);
-  optional<AEHAData> decode(RemoteReceiveData src);
-  void dump(const AEHAData &data);
+  void encode(RemoteTransmitData *dst, const AEHAData &data) override;
+  optional<AEHAData> decode(RemoteReceiveData src) override;
+  void dump(const AEHAData &data) override;
 
  private:
   std::string format_data_(const std::vector<uint8_t> &data);

esphome/components/remote_base/beo4_protocol.h

@@ -16,9 +16,9 @@ struct Beo4Data {
 
 class Beo4Protocol : public RemoteProtocol<Beo4Data> {
  public:
-  void encode(RemoteTransmitData *dst, const Beo4Data &data);
-  optional<Beo4Data> decode(RemoteReceiveData src);
-  void dump(const Beo4Data &data);
+  void encode(RemoteTransmitData *dst, const Beo4Data &data) override;
+  optional<Beo4Data> decode(RemoteReceiveData src) override;
+  void dump(const Beo4Data &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(Beo4)

esphome/components/remote_base/brennenstuhl_protocol.h

@@ -13,9 +13,9 @@ struct BrennenstuhlData {
 
 class BrennenstuhlProtocol : public RemoteProtocol<BrennenstuhlData> {
  public:
-  void encode(RemoteTransmitData *dst, const BrennenstuhlData &data);
-  optional<BrennenstuhlData> decode(RemoteReceiveData src);
-  void dump(const BrennenstuhlData &data);
+  void encode(RemoteTransmitData *dst, const BrennenstuhlData &data) override;
+  optional<BrennenstuhlData> decode(RemoteReceiveData src) override;
+  void dump(const BrennenstuhlData &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(Brennenstuhl)

esphome/components/remote_base/byronsx_protocol.h

@@ -21,9 +21,9 @@ struct ByronSXData {
 
 class ByronSXProtocol : public RemoteProtocol<ByronSXData> {
  public:
-  void encode(RemoteTransmitData *dst, const ByronSXData &data);
-  optional<ByronSXData> decode(RemoteReceiveData src);
-  void dump(const ByronSXData &data);
+  void encode(RemoteTransmitData *dst, const ByronSXData &data) override;
+  optional<ByronSXData> decode(RemoteReceiveData src) override;
+  void dump(const ByronSXData &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(ByronSX)

esphome/components/remote_base/canalsat_protocol.h

@@ -19,9 +19,9 @@ struct CanalSatLDData : public CanalSatData {};
 
 class CanalSatBaseProtocol : public RemoteProtocol<CanalSatData> {
  public:
-  void encode(RemoteTransmitData *dst, const CanalSatData &data);
-  optional<CanalSatData> decode(RemoteReceiveData src);
-  void dump(const CanalSatData &data);
+  void encode(RemoteTransmitData *dst, const CanalSatData &data) override;
+  optional<CanalSatData> decode(RemoteReceiveData src) override;
+  void dump(const CanalSatData &data) override;
 
  protected:
   uint16_t frequency_;

esphome/components/remote_base/coolix_protocol.h

@@ -21,9 +21,9 @@ struct CoolixData {
 
 class CoolixProtocol : public RemoteProtocol<CoolixData> {
  public:
-  void encode(RemoteTransmitData *dst, const CoolixData &data);
-  optional<CoolixData> decode(RemoteReceiveData data);
-  void dump(const CoolixData &data);
+  void encode(RemoteTransmitData *dst, const CoolixData &data) override;
+  optional<CoolixData> decode(RemoteReceiveData data) override;
+  void dump(const CoolixData &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(Coolix)

esphome/components/remote_base/dish_protocol.h

@@ -13,9 +13,9 @@ struct DishData {
 
 class DishProtocol : public RemoteProtocol<DishData> {
  public:
-  void encode(RemoteTransmitData *dst, const DishData &data);
-  optional<DishData> decode(RemoteReceiveData src);
-  void dump(const DishData &data);
+  void encode(RemoteTransmitData *dst, const DishData &data) override;
+  optional<DishData> decode(RemoteReceiveData src) override;
+  void dump(const DishData &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(Dish)

esphome/components/remote_base/dooya_protocol.h

@@ -20,9 +20,9 @@ struct DooyaData {
 
 class DooyaProtocol : public RemoteProtocol<DooyaData> {
  public:
-  void encode(RemoteTransmitData *dst, const DooyaData &data);
-  optional<DooyaData> decode(RemoteReceiveData src);
-  void dump(const DooyaData &data);
+  void encode(RemoteTransmitData *dst, const DooyaData &data) override;
+  optional<DooyaData> decode(RemoteReceiveData src) override;
+  void dump(const DooyaData &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(Dooya)

esphome/components/remote_base/drayton_protocol.h

@@ -19,9 +19,9 @@ struct DraytonData {
 
 class DraytonProtocol : public RemoteProtocol<DraytonData> {
  public:
-  void encode(RemoteTransmitData *dst, const DraytonData &data);
-  optional<DraytonData> decode(RemoteReceiveData src);
-  void dump(const DraytonData &data);
+  void encode(RemoteTransmitData *dst, const DraytonData &data) override;
+  optional<DraytonData> decode(RemoteReceiveData src) override;
+  void dump(const DraytonData &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(Drayton)

esphome/components/remote_base/dyson_protocol.h

@@ -21,9 +21,9 @@ struct DysonData {
 
 class DysonProtocol : public RemoteProtocol<DysonData> {
  public:
-  void encode(RemoteTransmitData *dst, const DysonData &data);
-  optional<DysonData> decode(RemoteReceiveData src);
-  void dump(const DysonData &data);
+  void encode(RemoteTransmitData *dst, const DysonData &data) override;
+  optional<DysonData> decode(RemoteReceiveData src) override;
+  void dump(const DysonData &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(Dyson)

esphome/components/remote_base/gobox_protocol.h

@@ -31,9 +31,9 @@ class GoboxProtocol : public RemoteProtocol<GoboxData> {
   void dump_timings_(const RawTimings &timings) const;
 
  public:
-  void encode(RemoteTransmitData *dst, const GoboxData &data);
-  optional<GoboxData> decode(RemoteReceiveData src);
-  void dump(const GoboxData &data);
+  void encode(RemoteTransmitData *dst, const GoboxData &data) override;
+  optional<GoboxData> decode(RemoteReceiveData src) override;
+  void dump(const GoboxData &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(Gobox)

esphome/components/remote_base/haier_protocol.h

@@ -13,9 +13,9 @@ struct HaierData {
 
 class HaierProtocol : public RemoteProtocol<HaierData> {
  public:
-  void encode(RemoteTransmitData *dst, const HaierData &data);
-  optional<HaierData> decode(RemoteReceiveData src);
-  void dump(const HaierData &data);
+  void encode(RemoteTransmitData *dst, const HaierData &data) override;
+  optional<HaierData> decode(RemoteReceiveData src) override;
+  void dump(const HaierData &data) override;
 
  protected:
   void encode_byte_(RemoteTransmitData *dst, uint8_t item);

esphome/components/remote_base/jvc_protocol.h

@@ -14,9 +14,9 @@ struct JVCData {
 
 class JVCProtocol : public RemoteProtocol<JVCData> {
  public:
-  void encode(RemoteTransmitData *dst, const JVCData &data);
-  optional<JVCData> decode(RemoteReceiveData src);
-  void dump(const JVCData &data);
+  void encode(RemoteTransmitData *dst, const JVCData &data) override;
+  optional<JVCData> decode(RemoteReceiveData src) override;
+  void dump(const JVCData &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(JVC)

esphome/components/remote_base/keeloq_protocol.h

@@ -24,9 +24,9 @@ struct KeeloqData {
 
 class KeeloqProtocol : public RemoteProtocol<KeeloqData> {
  public:
-  void encode(RemoteTransmitData *dst, const KeeloqData &data);
-  optional<KeeloqData> decode(RemoteReceiveData src);
-  void dump(const KeeloqData &data);
+  void encode(RemoteTransmitData *dst, const KeeloqData &data) override;
+  optional<KeeloqData> decode(RemoteReceiveData src) override;
+  void dump(const KeeloqData &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(Keeloq)

esphome/components/remote_base/lg_protocol.h

@@ -16,9 +16,9 @@ struct LGData {
 
 class LGProtocol : public RemoteProtocol<LGData> {
  public:
-  void encode(RemoteTransmitData *dst, const LGData &data);
-  optional<LGData> decode(RemoteReceiveData src);
-  void dump(const LGData &data);
+  void encode(RemoteTransmitData *dst, const LGData &data) override;
+  optional<LGData> decode(RemoteReceiveData src) override;
+  void dump(const LGData &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(LG)

esphome/components/remote_base/magiquest_protocol.h

@@ -27,9 +27,9 @@ struct MagiQuestData {
 
 class MagiQuestProtocol : public RemoteProtocol<MagiQuestData> {
  public:
-  void encode(RemoteTransmitData *dst, const MagiQuestData &data);
-  optional<MagiQuestData> decode(RemoteReceiveData src);
-  void dump(const MagiQuestData &data);
+  void encode(RemoteTransmitData *dst, const MagiQuestData &data) override;
+  optional<MagiQuestData> decode(RemoteReceiveData src) override;
+  void dump(const MagiQuestData &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(MagiQuest)

esphome/components/remote_base/midea_protocol.h

@@ -67,9 +67,9 @@ class MideaData {
 
 class MideaProtocol : public RemoteProtocol<MideaData> {
  public:
-  void encode(RemoteTransmitData *dst, const MideaData &src);
-  optional<MideaData> decode(RemoteReceiveData src);
-  void dump(const MideaData &data);
+  void encode(RemoteTransmitData *dst, const MideaData &src) override;
+  optional<MideaData> decode(RemoteReceiveData src) override;
+  void dump(const MideaData &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(Midea)

esphome/components/remote_base/mirage_protocol.h

@@ -13,9 +13,9 @@ struct MirageData {
 
 class MirageProtocol : public RemoteProtocol<MirageData> {
  public:
-  void encode(RemoteTransmitData *dst, const MirageData &data);
-  optional<MirageData> decode(RemoteReceiveData src);
-  void dump(const MirageData &data);
+  void encode(RemoteTransmitData *dst, const MirageData &data) override;
+  optional<MirageData> decode(RemoteReceiveData src) override;
+  void dump(const MirageData &data) override;
 
  protected:
   void encode_byte_(RemoteTransmitData *dst, uint8_t item);

esphome/components/remote_base/nec_protocol.h

@@ -14,9 +14,9 @@ struct NECData {
 
 class NECProtocol : public RemoteProtocol<NECData> {
  public:
-  void encode(RemoteTransmitData *dst, const NECData &data);
-  optional<NECData> decode(RemoteReceiveData src);
-  void dump(const NECData &data);
+  void encode(RemoteTransmitData *dst, const NECData &data) override;
+  optional<NECData> decode(RemoteReceiveData src) override;
+  void dump(const NECData &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(NEC)

esphome/components/remote_base/nexa_protocol.h

@@ -24,9 +24,9 @@ class NexaProtocol : public RemoteProtocol<NexaData> {
   void zero(RemoteTransmitData *dst) const;
   void sync(RemoteTransmitData *dst) const;
 
-  void encode(RemoteTransmitData *dst, const NexaData &data);
-  optional<NexaData> decode(RemoteReceiveData src);
-  void dump(const NexaData &data);
+  void encode(RemoteTransmitData *dst, const NexaData &data) override;
+  optional<NexaData> decode(RemoteReceiveData src) override;
+  void dump(const NexaData &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(Nexa)

esphome/components/remote_base/panasonic_protocol.h

@@ -16,9 +16,9 @@ struct PanasonicData {
 
 class PanasonicProtocol : public RemoteProtocol<PanasonicData> {
  public:
-  void encode(RemoteTransmitData *dst, const PanasonicData &data);
-  optional<PanasonicData> decode(RemoteReceiveData src);
-  void dump(const PanasonicData &data);
+  void encode(RemoteTransmitData *dst, const PanasonicData &data) override;
+  optional<PanasonicData> decode(RemoteReceiveData src) override;
+  void dump(const PanasonicData &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(Panasonic)

esphome/components/remote_base/pioneer_protocol.h

@@ -13,9 +13,9 @@ struct PioneerData {
 
 class PioneerProtocol : public RemoteProtocol<PioneerData> {
  public:
-  void encode(RemoteTransmitData *dst, const PioneerData &data);
-  optional<PioneerData> decode(RemoteReceiveData src);
-  void dump(const PioneerData &data);
+  void encode(RemoteTransmitData *dst, const PioneerData &data) override;
+  optional<PioneerData> decode(RemoteReceiveData src) override;
+  void dump(const PioneerData &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(Pioneer)

esphome/components/remote_base/pronto_protocol.h

@@ -30,9 +30,9 @@ class ProntoProtocol : public RemoteProtocol<ProntoData> {
   std::string compensate_and_dump_sequence_(const RawTimings &data, uint16_t timebase);
 
  public:
-  void encode(RemoteTransmitData *dst, const ProntoData &data);
-  optional<ProntoData> decode(RemoteReceiveData src);
-  void dump(const ProntoData &data);
+  void encode(RemoteTransmitData *dst, const ProntoData &data) override;
+  optional<ProntoData> decode(RemoteReceiveData src) override;
+  void dump(const ProntoData &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(Pronto)

esphome/components/remote_base/rc5_protocol.h

@@ -14,9 +14,9 @@ struct RC5Data {
 
 class RC5Protocol : public RemoteProtocol<RC5Data> {
  public:
-  void encode(RemoteTransmitData *dst, const RC5Data &data);
-  optional<RC5Data> decode(RemoteReceiveData src);
-  void dump(const RC5Data &data);
+  void encode(RemoteTransmitData *dst, const RC5Data &data) override;
+  optional<RC5Data> decode(RemoteReceiveData src) override;
+  void dump(const RC5Data &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(RC5)

esphome/components/remote_base/rc6_protocol.h

@@ -15,9 +15,9 @@ struct RC6Data {
 
 class RC6Protocol : public RemoteProtocol<RC6Data> {
  public:
-  void encode(RemoteTransmitData *dst, const RC6Data &data);
-  optional<RC6Data> decode(RemoteReceiveData src);
-  void dump(const RC6Data &data);
+  void encode(RemoteTransmitData *dst, const RC6Data &data) override;
+  optional<RC6Data> decode(RemoteReceiveData src) override;
+  void dump(const RC6Data &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(RC6)

esphome/components/remote_base/rc_switch_protocol.cpp

@@ -1,12 +1,30 @@
 #include "rc_switch_protocol.h"
-
-#include <iterator>
 #include "esphome/core/log.h"
 
 namespace esphome::remote_base {
 
 static const char *const TAG = "remote.rc_switch";
 
+const RCSwitchBase RC_SWITCH_PROTOCOLS[9] = {RCSwitchBase(0, 0, 0, 0, 0, 0, false),
+                                             RCSwitchBase(350, 10850, 350, 1050, 1050, 350, false),
+                                             RCSwitchBase(650, 6500, 650, 1300, 1300, 650, false),
+                                             RCSwitchBase(3000, 7100, 400, 1100, 900, 600, false),
+                                             RCSwitchBase(380, 2280, 380, 1140, 1140, 380, false),
+                                             RCSwitchBase(3000, 7000, 500, 1000, 1000, 500, false),
+                                             RCSwitchBase(10350, 450, 450, 900, 900, 450, true),
+                                             RCSwitchBase(300, 9300, 150, 900, 900, 150, false),
+                                             RCSwitchBase(250, 2500, 250, 1250, 250, 250, false)};
+
+RCSwitchBase::RCSwitchBase(uint32_t sync_high, uint32_t sync_low, uint32_t zero_high, uint32_t zero_low,
+                           uint32_t one_high, uint32_t one_low, bool inverted)
+    : sync_high_(sync_high),
+      sync_low_(sync_low),
+      zero_high_(zero_high),
+      zero_low_(zero_low),
+      one_high_(one_high),
+      one_low_(one_low),
+      inverted_(inverted) {}
+
 void RCSwitchBase::one(RemoteTransmitData *dst) const {
   if (!this->inverted_) {
     dst->mark(this->one_high_);
@@ -115,11 +133,11 @@ bool RCSwitchBase::decode(RemoteReceiveData &src, uint64_t *out_data, uint8_t *o
 optional<RCSwitchData> RCSwitchBase::decode(RemoteReceiveData &src) const {
   RCSwitchData out;
   uint8_t out_nbits;
-  for (size_t i = 1; i < std::size(RC_SWITCH_PROTOCOLS); i++) {
+  for (uint8_t i = 1; i <= 8; i++) {
     src.reset();
     const RCSwitchBase *protocol = &RC_SWITCH_PROTOCOLS[i];
     if (protocol->decode(src, &out.code, &out_nbits) && out_nbits >= 3) {
-      out.protocol = static_cast<uint8_t>(i);
+      out.protocol = i;
       return out;
     }
   }
@@ -228,7 +246,7 @@ bool RCSwitchRawReceiver::matches(RemoteReceiveData src) {
   return decoded_nbits == this->nbits_ && (decoded_code & this->mask_) == (this->code_ & this->mask_);
 }
 bool RCSwitchDumper::dump(RemoteReceiveData src) {
-  for (size_t i = 1; i < std::size(RC_SWITCH_PROTOCOLS); i++) {
+  for (uint8_t i = 1; i <= 8; i++) {
     src.reset();
     uint64_t out_data;
     uint8_t out_nbits;
@@ -239,7 +257,7 @@ bool RCSwitchDumper::dump(RemoteReceiveData src) {
         buffer[j] = (out_data & ((uint64_t) 1 << (out_nbits - j - 1))) ? '1' : '0';
 
       buffer[out_nbits] = '\0';
-      ESP_LOGI(TAG, "Received RCSwitch Raw: protocol=%u data='%s'", static_cast<unsigned>(i), buffer);
+      ESP_LOGI(TAG, "Received RCSwitch Raw: protocol=%u data='%s'", i, buffer);
 
       // only send first decoded protocol
       return true;

esphome/components/remote_base/rc_switch_protocol.h

@@ -16,16 +16,9 @@ class RCSwitchBase {
  public:
   using ProtocolData = RCSwitchData;
 
-  constexpr RCSwitchBase() = default;
-  constexpr RCSwitchBase(uint32_t sync_high, uint32_t sync_low, uint32_t zero_high, uint32_t zero_low,
-                         uint32_t one_high, uint32_t one_low, bool inverted)
-      : sync_high_(sync_high),
-        sync_low_(sync_low),
-        zero_high_(zero_high),
-        zero_low_(zero_low),
-        one_high_(one_high),
-        one_low_(one_low),
-        inverted_(inverted) {}
+  RCSwitchBase() = default;
+  RCSwitchBase(uint32_t sync_high, uint32_t sync_low, uint32_t zero_high, uint32_t zero_low, uint32_t one_high,
+               uint32_t one_low, bool inverted);
 
   void one(RemoteTransmitData *dst) const;
 
@@ -65,21 +58,10 @@ class RCSwitchBase {
   uint32_t zero_low_{};
   uint32_t one_high_{};
   uint32_t one_low_{};
-  uint32_t inverted_{};  // bool widened so every field is a word: the table is read from flash
+  bool inverted_{};
 };
 
-// Constant-initialized and kept in flash on every platform; all fields are 32-bit so ESP8266 can read it in place
-inline constexpr RCSwitchBase RC_SWITCH_PROTOCOLS[] PROGMEM = {
-    {0, 0, 0, 0, 0, 0, false},
-    {350, 10850, 350, 1050, 1050, 350, false},
-    {650, 6500, 650, 1300, 1300, 650, false},
-    {3000, 7100, 400, 1100, 900, 600, false},
-    {380, 2280, 380, 1140, 1140, 380, false},
-    {3000, 7000, 500, 1000, 1000, 500, false},
-    {10350, 450, 450, 900, 900, 450, true},
-    {300, 9300, 150, 900, 900, 150, false},
-    {250, 2500, 250, 1250, 250, 250, false},
-};
+extern const RCSwitchBase RC_SWITCH_PROTOCOLS[9];
 
 uint64_t decode_binary_string(const std::string &data);
 

esphome/components/remote_base/remote_base.cpp

@@ -99,47 +99,29 @@ bool RemoteReceiverBinarySensorBase::on_receive(RemoteReceiveData src) {
 
 /* RemoteReceiverBase */
 
-// Slots are counted at code generation; a registration from C++ setup() has none
-#ifdef REMOTE_BASE_LISTENER_COUNT
-void RemoteReceiverBase::register_listener(RemoteReceiverListener *listener) {
-  if (this->listeners_.size() == REMOTE_BASE_LISTENER_COUNT) {
-    ESP_LOGE(TAG, "No %s slot: register it from to_code() with remote_base.add_%s", LOG_STR_LITERAL("listener"),
-             LOG_STR_LITERAL("listener"));
-    return;
-  }
-  this->listeners_.push_back(listener);
-}
-#endif
-
-#ifdef REMOTE_BASE_DUMPER_COUNT
 void RemoteReceiverBase::register_dumper(RemoteReceiverDumperBase *dumper) {
   if (dumper->is_secondary()) {
-    this->secondary_dumper_ = dumper;
-    return;
+    this->secondary_dumpers_.push_back(dumper);
+  } else {
+    this->dumpers_.push_back(dumper);
   }
-  if (this->dumpers_.size() == REMOTE_BASE_DUMPER_COUNT) {
-    ESP_LOGE(TAG, "No %s slot: register it from to_code() with remote_base.add_%s", LOG_STR_LITERAL("dumper"),
-             LOG_STR_LITERAL("dumper"));
-    return;
-  }
-  this->dumpers_.push_back(dumper);
 }
-#endif
 
-void RemoteReceiverBase::call_listeners_dumpers_() {
-#ifdef REMOTE_BASE_LISTENER_COUNT
+void RemoteReceiverBase::call_listeners_() {
   for (auto *listener : this->listeners_)
     listener->on_receive(RemoteReceiveData(this->temp_, this->tolerance_, this->tolerance_mode_));
-#endif
-#ifdef REMOTE_BASE_DUMPER_COUNT
+}
+
+void RemoteReceiverBase::call_dumpers_() {
   bool success = false;
   for (auto *dumper : this->dumpers_) {
     if (dumper->dump(RemoteReceiveData(this->temp_, this->tolerance_, this->tolerance_mode_)))
       success = true;
   }
-  if (!success && this->secondary_dumper_ != nullptr)
-    this->secondary_dumper_->dump(RemoteReceiveData(this->temp_, this->tolerance_, this->tolerance_mode_));
-#endif
+  if (!success) {
+    for (auto *dumper : this->secondary_dumpers_)
+      dumper->dump(RemoteReceiveData(this->temp_, this->tolerance_, this->tolerance_mode_));
+  }
 }
 
 void RemoteReceiverBinarySensorBase::dump_config() { LOG_BINARY_SENSOR("", "Remote Receiver Binary Sensor", this); }

esphome/components/remote_base/remote_base.h

@@ -1,14 +1,12 @@
-#pragma once
-
-#include <concepts>
 #include <utility>
 #include <vector>
 
+#pragma once
+
 #include "esphome/components/binary_sensor/binary_sensor.h"
 #include "esphome/core/automation.h"
 #include "esphome/core/component.h"
 #include "esphome/core/hal.h"
-#include "esphome/core/helpers.h"
 
 namespace esphome::remote_base {
 
@@ -143,22 +141,6 @@ class RemoteRMTChannel {
 #endif  // SOC_RMT_SUPPORTED
 #endif  // USE_ESP32
 
-// Protocol shapes, checked where a protocol is used so a missing method fails at the use site
-// instead of deep inside a template body. Receive-only protocols such as RCSwitchBase decode
-// without encoding.
-template<typename T>
-concept RemoteProtocolDecoder = requires(T proto, RemoteReceiveData src) {
-  { proto.decode(src) } -> std::same_as<optional<typename T::ProtocolData>>;
-};
-template<typename T>
-concept RemoteProtocolDumper = RemoteProtocolDecoder<T> && requires(T proto, const typename T::ProtocolData &data) {
-  proto.dump(data);
-};
-template<typename T>
-concept RemoteProtocolEncoder = requires(T proto, RemoteTransmitData *dst, const typename T::ProtocolData &data) {
-  proto.encode(dst, data);
-};
-
 class RemoteTransmitterBase : public RemoteComponentBase {
  public:
   RemoteTransmitterBase(InternalGPIOPin *pin) : RemoteComponentBase(pin) {}
@@ -180,7 +162,7 @@ class RemoteTransmitterBase : public RemoteComponentBase {
     this->temp_.reset();
     return TransmitCall(this);
   }
-  template<RemoteProtocolEncoder Protocol>
+  template<typename Protocol>
   void transmit(const Protocol::ProtocolData &data, uint32_t send_times = 1, uint32_t send_wait = 0) {
     auto call = this->transmit();
     Protocol().encode(call.get_data(), data);
@@ -212,37 +194,24 @@ class RemoteReceiverDumperBase {
 class RemoteReceiverBase : public RemoteComponentBase {
  public:
   RemoteReceiverBase(InternalGPIOPin *pin) : RemoteComponentBase(pin) {}
-  // Slots are counted at code generation; without one the call fails at compile time with the same message
-  // the runtime check logs
-#ifdef REMOTE_BASE_LISTENER_COUNT
-  void register_listener(RemoteReceiverListener *listener);
-#else
-  template<typename T> void register_listener(T *) {
-    static_assert(sizeof(T) == 0, "No listener slot: register it from to_code() with remote_base.add_listener");
-  }
-#endif
-#ifdef REMOTE_BASE_DUMPER_COUNT
+  void register_listener(RemoteReceiverListener *listener) { this->listeners_.push_back(listener); }
   void register_dumper(RemoteReceiverDumperBase *dumper);
-#else
-  template<typename T> void register_dumper(T *) {
-    static_assert(sizeof(T) == 0, "No dumper slot: register it from to_code() with remote_base.add_dumper");
-  }
-#endif
   void set_tolerance(uint32_t tolerance, ToleranceMode tolerance_mode) {
     this->tolerance_ = tolerance;
     this->tolerance_mode_ = tolerance_mode;
   }
 
  protected:
-  void call_listeners_dumpers_();
+  void call_listeners_();
+  void call_dumpers_();
+  void call_listeners_dumpers_() {
+    this->call_listeners_();
+    this->call_dumpers_();
+  }
 
-#ifdef REMOTE_BASE_LISTENER_COUNT
-  StaticVector<RemoteReceiverListener *, REMOTE_BASE_LISTENER_COUNT> listeners_;
-#endif
-#ifdef REMOTE_BASE_DUMPER_COUNT
-  StaticVector<RemoteReceiverDumperBase *, REMOTE_BASE_DUMPER_COUNT> dumpers_;
-  RemoteReceiverDumperBase *secondary_dumper_{nullptr};  // runs only when no primary dumper matched
-#endif
+  std::vector<RemoteReceiverListener *> listeners_;
+  std::vector<RemoteReceiverDumperBase *> dumpers_;
+  std::vector<RemoteReceiverDumperBase *> secondary_dumpers_;
   RawTimings temp_;
   uint32_t tolerance_{25};
   ToleranceMode tolerance_mode_{TOLERANCE_MODE_PERCENTAGE};
@@ -260,14 +229,15 @@ class RemoteReceiverBinarySensorBase : public binary_sensor::BinarySensorInitial
 
 /* TEMPLATES */
 
-// Protocols are used only through their concrete type (see the RemoteProtocol* concepts); encode/decode/dump
-// stay non-virtual so unused ones link out
 template<typename T> class RemoteProtocol {
  public:
   using ProtocolData = T;
+  virtual void encode(RemoteTransmitData *dst, const ProtocolData &data) = 0;
+  virtual optional<ProtocolData> decode(RemoteReceiveData src) = 0;
+  virtual void dump(const ProtocolData &data) = 0;
 };
 
-template<RemoteProtocolDecoder T> class RemoteReceiverBinarySensor : public RemoteReceiverBinarySensorBase {
+template<typename T> class RemoteReceiverBinarySensor : public RemoteReceiverBinarySensorBase {
  public:
   RemoteReceiverBinarySensor() : RemoteReceiverBinarySensorBase() {}
 
@@ -285,7 +255,7 @@ template<RemoteProtocolDecoder T> class RemoteReceiverBinarySensor : public Remo
   T::ProtocolData data_;
 };
 
-template<RemoteProtocolDecoder T>
+template<typename T>
 class RemoteReceiverTrigger final : public Trigger<typename T::ProtocolData>, public RemoteReceiverListener {
  protected:
   bool on_receive(RemoteReceiveData src) override {
@@ -306,7 +276,7 @@ class RemoteTransmittable {
   void set_transmitter(RemoteTransmitterBase *transmitter) { this->transmitter_ = transmitter; }
 
  protected:
-  template<RemoteProtocolEncoder Protocol>
+  template<typename Protocol>
   void transmit_(const Protocol::ProtocolData &data, uint32_t send_times = 1, uint32_t send_wait = 0) {
     this->transmitter_->transmit<Protocol>(data, send_times, send_wait);
   }
@@ -328,7 +298,7 @@ template<typename... Ts> class RemoteTransmitterActionBase : public RemoteTransm
   virtual void encode(RemoteTransmitData *dst, Ts... x) = 0;
 };
 
-template<RemoteProtocolDumper T> class RemoteReceiverDumper : public RemoteReceiverDumperBase {
+template<typename T> class RemoteReceiverDumper : public RemoteReceiverDumperBase {
  public:
   bool dump(RemoteReceiveData src) override {
     auto proto = T();

esphome/components/remote_base/roomba_protocol.h

@@ -12,9 +12,9 @@ struct RoombaData {
 
 class RoombaProtocol : public RemoteProtocol<RoombaData> {
  public:
-  void encode(RemoteTransmitData *dst, const RoombaData &data);
-  optional<RoombaData> decode(RemoteReceiveData src);
-  void dump(const RoombaData &data);
+  void encode(RemoteTransmitData *dst, const RoombaData &data) override;
+  optional<RoombaData> decode(RemoteReceiveData src) override;
+  void dump(const RoombaData &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(Roomba)

esphome/components/remote_base/samsung36_protocol.h

@@ -16,9 +16,9 @@ struct Samsung36Data {
 
 class Samsung36Protocol : public RemoteProtocol<Samsung36Data> {
  public:
-  void encode(RemoteTransmitData *dst, const Samsung36Data &data);
-  optional<Samsung36Data> decode(RemoteReceiveData src);
-  void dump(const Samsung36Data &data);
+  void encode(RemoteTransmitData *dst, const Samsung36Data &data) override;
+  optional<Samsung36Data> decode(RemoteReceiveData src) override;
+  void dump(const Samsung36Data &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(Samsung36)

esphome/components/remote_base/samsung_protocol.h

@@ -14,9 +14,9 @@ struct SamsungData {
 
 class SamsungProtocol : public RemoteProtocol<SamsungData> {
  public:
-  void encode(RemoteTransmitData *dst, const SamsungData &data);
-  optional<SamsungData> decode(RemoteReceiveData src);
-  void dump(const SamsungData &data);
+  void encode(RemoteTransmitData *dst, const SamsungData &data) override;
+  optional<SamsungData> decode(RemoteReceiveData src) override;
+  void dump(const SamsungData &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(Samsung)

esphome/components/remote_base/sony_protocol.h

@@ -16,9 +16,9 @@ struct SonyData {
 
 class SonyProtocol : public RemoteProtocol<SonyData> {
  public:
-  void encode(RemoteTransmitData *dst, const SonyData &data);
-  optional<SonyData> decode(RemoteReceiveData src);
-  void dump(const SonyData &data);
+  void encode(RemoteTransmitData *dst, const SonyData &data) override;
+  optional<SonyData> decode(RemoteReceiveData src) override;
+  void dump(const SonyData &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(Sony)

esphome/components/remote_base/symphony_protocol.h

@@ -17,9 +17,9 @@ struct SymphonyData {
 
 class SymphonyProtocol : public RemoteProtocol<SymphonyData> {
  public:
-  void encode(RemoteTransmitData *dst, const SymphonyData &data);
-  optional<SymphonyData> decode(RemoteReceiveData src);
-  void dump(const SymphonyData &data);
+  void encode(RemoteTransmitData *dst, const SymphonyData &data) override;
+  optional<SymphonyData> decode(RemoteReceiveData src) override;
+  void dump(const SymphonyData &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(Symphony)

esphome/components/remote_base/toshiba_ac_protocol.h

@@ -14,9 +14,9 @@ struct ToshibaAcData {
 
 class ToshibaAcProtocol : public RemoteProtocol<ToshibaAcData> {
  public:
-  void encode(RemoteTransmitData *dst, const ToshibaAcData &data);
-  optional<ToshibaAcData> decode(RemoteReceiveData src);
-  void dump(const ToshibaAcData &data);
+  void encode(RemoteTransmitData *dst, const ToshibaAcData &data) override;
+  optional<ToshibaAcData> decode(RemoteReceiveData src) override;
+  void dump(const ToshibaAcData &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(ToshibaAc)

esphome/components/remote_base/toto_protocol.h

@@ -16,9 +16,9 @@ struct TotoData {
 
 class TotoProtocol : public RemoteProtocol<TotoData> {
  public:
-  void encode(RemoteTransmitData *dst, const TotoData &data);
-  optional<TotoData> decode(RemoteReceiveData src);
-  void dump(const TotoData &data);
+  void encode(RemoteTransmitData *dst, const TotoData &data) override;
+  optional<TotoData> decode(RemoteReceiveData src) override;
+  void dump(const TotoData &data) override;
 };
 
 DECLARE_REMOTE_PROTOCOL(Toto)

esphome/components/remote_receiver/__init__.py

@@ -221,11 +221,11 @@ async def to_code(config: ConfigType) -> None:
 
     dumpers = await remote_base.build_dumpers(config[CONF_DUMP])
     for dumper in dumpers:
-        remote_base.add_dumper(var, dumper)
+        cg.add(var.register_dumper(dumper))
 
     triggers = await remote_base.build_triggers(config)
     for trigger in triggers:
-        remote_base.add_listener(var, trigger)
+        cg.add(var.register_listener(trigger))
     await cg.register_component(var, config)
 
     cg.add(

esphome/components/toshiba/climate.py

@@ -1,5 +1,5 @@
 import esphome.codegen as cg
-from esphome.components import climate_ir, remote_base
+from esphome.components import climate_ir
 import esphome.config_validation as cv
 from esphome.const import CONF_MODEL
 from esphome.types import ConfigType
@@ -26,6 +26,5 @@ CONFIG_SCHEMA = climate_ir.climate_ir_with_receiver_schema(ToshibaClimate).exten
 
 
 async def to_code(config: ConfigType) -> None:
-    remote_base.request_protocol("toshiba_ac")  # used from C++
     var = await climate_ir.new_climate_ir(config)
     cg.add(var.set_model(config[CONF_MODEL]))

esphome/core/defines.h

@@ -137,43 +137,6 @@
 #define MICRONOVA_LISTENER_COUNT 1
 #define USE_MICRONOVA_WRITER
 #define MK2PVROUTER_LISTENER_COUNT 1
-#define REMOTE_BASE_DUMPER_COUNT 1
-#define REMOTE_BASE_LISTENER_COUNT 1
-#define USE_REMOTE_PROTOCOL_ABBWELCOME
-#define USE_REMOTE_PROTOCOL_AEHA
-#define USE_REMOTE_PROTOCOL_BEO4
-#define USE_REMOTE_PROTOCOL_BRENNENSTUHL
-#define USE_REMOTE_PROTOCOL_BYRONSX
-#define USE_REMOTE_PROTOCOL_CANALSAT
-#define USE_REMOTE_PROTOCOL_COOLIX
-#define USE_REMOTE_PROTOCOL_DISH
-#define USE_REMOTE_PROTOCOL_DOOYA
-#define USE_REMOTE_PROTOCOL_DRAYTON
-#define USE_REMOTE_PROTOCOL_DYSON
-#define USE_REMOTE_PROTOCOL_GOBOX
-#define USE_REMOTE_PROTOCOL_HAIER
-#define USE_REMOTE_PROTOCOL_JVC
-#define USE_REMOTE_PROTOCOL_KEELOQ
-#define USE_REMOTE_PROTOCOL_LG
-#define USE_REMOTE_PROTOCOL_MAGIQUEST
-#define USE_REMOTE_PROTOCOL_MIDEA
-#define USE_REMOTE_PROTOCOL_MIRAGE
-#define USE_REMOTE_PROTOCOL_NEC
-#define USE_REMOTE_PROTOCOL_NEXA
-#define USE_REMOTE_PROTOCOL_PANASONIC
-#define USE_REMOTE_PROTOCOL_PIONEER
-#define USE_REMOTE_PROTOCOL_PRONTO
-#define USE_REMOTE_PROTOCOL_RAW
-#define USE_REMOTE_PROTOCOL_RC5
-#define USE_REMOTE_PROTOCOL_RC6
-#define USE_REMOTE_PROTOCOL_RC_SWITCH
-#define USE_REMOTE_PROTOCOL_ROOMBA
-#define USE_REMOTE_PROTOCOL_SAMSUNG
-#define USE_REMOTE_PROTOCOL_SAMSUNG36
-#define USE_REMOTE_PROTOCOL_SONY
-#define USE_REMOTE_PROTOCOL_SYMPHONY
-#define USE_REMOTE_PROTOCOL_TOSHIBA_AC
-#define USE_REMOTE_PROTOCOL_TOTO
 #define SERIAL_PROXY_COUNT 2
 #define SNTP_SERVER_COUNT 3
 #define USE_MEDIA_PLAYER

esphome/core/string_ref.h

@@ -22,6 +22,10 @@ namespace esphome {
  * pointer.  When it is default constructed, it has empty string.  You can freely copy or move around this struct, but
  * never free its pointer.  str() function can be used to export the content as std::string. StringRef is adopted from
  * <https://github.com/nghttp2/nghttp2/blob/29cbf8b83ff78faf405d1086b16adc09a8772eca/src/template.h#L376>
+ *
+ * A StringRef may carry a null pointer while its length is zero (the generated api messages start their encode only
+ * string fields that way). Every member treats that as the empty string; only c_str() hands the null pointer on, so
+ * callers that print or copy through c_str() must check empty() first.
  */
 class StringRef {
  public:
@@ -78,7 +82,7 @@ class StringRef {
 
   /// True if the view begins with the given prefix (std::string::starts_with-like)
   bool starts_with(const StringRef &prefix) const {
-    return len_ >= prefix.len_ && std::memcmp(base_, prefix.base_, prefix.len_) == 0;
+    return len_ >= prefix.len_ && (prefix.len_ == 0 || std::memcmp(base_, prefix.base_, prefix.len_) == 0);
   }
   bool starts_with(const char *prefix) const { return this->starts_with(StringRef(prefix)); }
   bool starts_with(const std::string &prefix) const { return this->starts_with(StringRef(prefix)); }
@@ -92,14 +96,15 @@ class StringRef {
     return actual;
   }
 
-  std::string str() const { return std::string(base_, len_); }
+  std::string str() const { return std::string(base_, len_); }  // fine for {nullptr, 0}: nothing is read
   const uint8_t *byte() const { return reinterpret_cast<const uint8_t *>(base_); }
 
   operator std::string() const { return str(); }
 
   /// Compare (compatible with std::string::compare)
   int compare(const StringRef &other) const {
-    int result = std::memcmp(base_, other.base_, std::min(len_, other.len_));
+    size_type common = std::min(len_, other.len_);
+    int result = common == 0 ? 0 : std::memcmp(base_, other.base_, common);
     if (result != 0)
       return result;
     if (len_ < other.len_)
@@ -258,7 +263,14 @@ inline double stod(const StringRef &str, size_t *pos = nullptr) {
 
 #ifdef USE_JSON
 // NOLINTNEXTLINE(readability-identifier-naming)
-inline void convertToJson(const StringRef &src, JsonVariant dst) { dst.set(src.c_str()); }
+inline void convertToJson(const StringRef &src, JsonVariant dst) {
+  // Bounded by the view length; a null, empty view becomes "" rather than JSON null
+  if (src.empty()) {
+    dst.set("");
+    return;
+  }
+  dst.set(JsonString(src.c_str(), src.size()));
+}
 #endif  // USE_JSON
 
 }  // namespace esphome

script/api_protobuf/api_protobuf.py

@@ -28,6 +28,11 @@ class WireType(IntEnum):
     END_GROUP = 4  # groups (deprecated)
     FIXED32 = 5  # fixed32, sfixed32, float
 
+    @property
+    def cpp_name(self) -> str:
+        """The matching constant in proto.h."""
+        return f"WIRE_TYPE_{self.name}"
+
 
 # Generate with
 # protoc --python_out=script/api_protobuf -I esphome/components/api/ api_options.proto
@@ -126,9 +131,10 @@ def camel_to_snake(name: str) -> str:
     return re.sub("([a-z0-9])([A-Z])", r"\1_\2", s1).lower()
 
 
-def force_str(force: bool) -> str:
-    """Convert a boolean force value to string format for C++ code."""
-    return str(force).lower()
+def _encode_call(func: str, *args: str, force: bool = False) -> str:
+    """Emit one ProtoEncode call; every helper takes the cursor and returns it advanced."""
+    suffix = "_force" if force else ""
+    return f"pos = ProtoEncode::{func}{suffix}({', '.join(('pos', *args))});"
 
 
 class TypeInfo(ABC):
@@ -223,55 +229,39 @@ class TypeInfo(ABC):
     def class_member(self) -> str:
         return f"{self.cpp_type} {self.field_name}{{{self.default_value}}};"
 
-    @property
-    def decode_varint_content(self) -> str:
-        content = self.decode_varint
-        if content is None:
-            return None
-        return f"case {self.number}: this->{self.field_name} = {content}; break;"
+    def decode_case(self, body: str) -> str:
+        """Emit one decode_field() case, keyed on the field's wire tag."""
+        return f"case proto_tag({self.number}, {self.wire_type.cpp_name}):\n" + indent(
+            f"{body}\nbreak;"
+        )
 
-    decode_varint = None
+    # Expression that reads this field from `value`; None when the type is never decoded.
+    decode_expr: str | None = None
+
+    def _decode_store(self, expr: str) -> str:
+        return f"this->{self.field_name} = {expr};"
 
     @property
-    def decode_length_content(self) -> str:
-        content = self.decode_length
-        if content is None:
-            return None
-        return f"case {self.number}: this->{self.field_name} = {content}; break;"
-
-    decode_length = None
-
-    @property
-    def decode_32bit_content(self) -> str:
-        content = self.decode_32bit
-        if content is None:
-            return None
-        return f"case {self.number}: this->{self.field_name} = {content}; break;"
-
-    decode_32bit = None
-
-    @property
-    def decode_64bit_content(self) -> str:
-        content = self.decode_64bit
-        if content is None:
-            return None
-        return f"case {self.number}: this->{self.field_name} = {content}; break;"
-
-    decode_64bit = None
+    def decode_content(self) -> str | None:
+        """The decode_field() case for this field, or None when it is never decoded."""
+        expr = self.decode_expr
+        return None if expr is None else self.decode_case(self._decode_store(expr))
 
     # Mapping from encode_func to raw encode expression template.
     # When a forced field has a single-byte tag, the code generator emits
     # write_raw_byte(tag) + raw encode instead of the full encode_* method,
     # eliminating the zero-check branch and encode_field_raw indirection.
     # {value} is replaced with the actual field expression.
-    RAW_ENCODE_MAP: dict[str, str] = {
-        "encode_uint32": "ProtoEncode::encode_varint_raw(pos, {value});",
-        "encode_uint64": "ProtoEncode::encode_varint_raw_64(pos, {value});",
-        "encode_sint32": "ProtoEncode::encode_varint_raw_short(pos, encode_zigzag32({value}));",
-        "encode_sint64": "ProtoEncode::encode_varint_raw_64(pos, encode_zigzag64({value}));",
-        "encode_int64": "ProtoEncode::encode_varint_raw_64(pos, static_cast<uint64_t>({value}));",
-        "encode_bool": "ProtoEncode::write_raw_byte(pos, {value} ? 0x01 : 0x00);",
+    RAW_ENCODE_MAP: dict[str, tuple[str, str]] = {
+        "encode_uint32": ("encode_varint_raw", "{value}"),
+        "encode_uint64": ("encode_varint_raw_64", "{value}"),
+        "encode_sint32": ("encode_varint_raw_short", "encode_zigzag32({value})"),
+        "encode_sint64": ("encode_varint_raw_64", "encode_zigzag64({value})"),
+        "encode_int64": ("encode_varint_raw_64", "static_cast<uint64_t>({value})"),
+        "encode_bool": ("write_raw_byte", "{value} ? 0x01 : 0x00"),
     }
+    # Fixed32 value expression for the shared tag+fixed32 writer; None for other wire types
+    fixed32_value_template: str | None = None
 
     def _encode_with_precomputed_tag(self, value_expr: str) -> str | None:
         """Try to emit a precomputed-tag encode for a field.
@@ -288,12 +278,17 @@ class TypeInfo(ABC):
             return None
         max_val = self.max_value
         # Only use RAW_ENCODE_MAP for forced fields or fields with max_value
-        raw_expr = None
+        raw = None
         if self.force or max_val is not None:
-            raw_expr = self.RAW_ENCODE_MAP.get(self.encode_func)
-        if raw_expr is None:
+            raw = self.RAW_ENCODE_MAP.get(self.encode_func)
+        if raw is None:
             return None
-        body = f"ProtoEncode::write_raw_byte(pos, {tag});\n{raw_expr.format(value=value_expr)}"
+        func, arg = raw
+        body = (
+            _encode_call("write_raw_byte", str(tag))
+            + "\n"
+            + _encode_call(func, arg.format(value=value_expr))
+        )
         if self.force:
             return body
         # Non-forced with max_value: inline zero-check + raw encode
@@ -314,23 +309,44 @@ class TypeInfo(ABC):
             return None
         # When max_len < 128, length varint is always 1 byte
         len_encode = (
-            f"ProtoEncode::write_raw_byte(pos, static_cast<uint8_t>({len_expr}));"
+            _encode_call("write_raw_byte", f"static_cast<uint8_t>({len_expr})")
             if max_len is not None and max_len < 128
-            else f"ProtoEncode::encode_varint_raw(pos, {len_expr});"
+            else _encode_call("encode_varint_raw", len_expr)
         )
+        return "\n".join(
+            (
+                _encode_call("write_raw_byte", str(tag)),
+                len_encode,
+                _encode_call("encode_raw", data_expr, len_expr),
+            )
+        )
+
+    def _encode_fixed32_with_precomputed_tag(self, value: str) -> str | None:
+        """Single-byte tag fixed32 write, or None for other types and multi-byte tags."""
+        tag = self.calculate_tag()
+        if self.fixed32_value_template is None or tag >= 128:
+            return None
+        value_expr = self.fixed32_value_template.format(value=value)
+        if self.force:
+            return _encode_call("write_tag_and_fixed32", str(tag), value_expr)
         return (
-            f"ProtoEncode::write_raw_byte(pos, {tag});\n"
-            f"{len_encode}\n"
-            f"ProtoEncode::encode_raw(pos, {data_expr}, {len_expr});"
+            f"if (uint32_t raw = {value_expr}; raw != 0) [[likely]] {{\n"
+            f"  {_encode_call('write_tag_and_fixed32', str(tag), 'raw')}\n"
+            "}"
         )
 
     @property
     def encode_content(self) -> str:
-        if result := self._encode_with_precomputed_tag(f"this->{self.field_name}"):
+        value = f"this->{self.field_name}"
+        if result := self._encode_with_precomputed_tag(value):
             return result
-        if self.force:
-            return f"ProtoEncode::{self.encode_func}(pos, {self.number}, this->{self.field_name}, true);"
-        return f"ProtoEncode::{self.encode_func}(pos, {self.number}, this->{self.field_name});"
+        if result := self._encode_fixed32_with_precomputed_tag(value):
+            return result
+        return _encode_call(self.encode_func, str(self.number), value, force=self.force)
+
+    def encode_element(self, number: int, element: str) -> str:
+        """Encode one element of a repeated field; elements are always written."""
+        return _encode_call(self.encode_func, str(number), element, force=True)
 
     encode_func = None
 
@@ -550,17 +566,17 @@ def create_field_type_info(
         # For messages that decode (SOURCE_CLIENT or SOURCE_BOTH), use pointer
         # for zero-copy access to the receive buffer
         if needs_decode:
-            return PointerToBytesBufferType(field, None)
+            return PointerToBytesBufferType(field, needs_decode)
 
         # For SOURCE_SERVER (encode only), explicit annotation is still needed
         if get_field_opt(field, pb.pointer_to_buffer, False):
-            return PointerToBytesBufferType(field, None)
+            return PointerToBytesBufferType(field, needs_decode)
 
         return BytesType(field, needs_decode, needs_encode)
 
     # Special handling for string fields - use StringRef for zero-copy
     if field.type == 9:
-        return PointerToStringBufferType(field, None)
+        return PointerToStringBufferType(field, needs_decode)
 
     validate_field_type(field.type, field.name)
     if field.type == 11:
@@ -605,7 +621,6 @@ class DoubleType(FixedSizeTypeMixin, TypeInfo):
     # Unsupported but defined for completeness
     cpp_type = "double"
     default_value = "0.0"
-    decode_64bit = "value.as_double()"
     encode_func = "encode_double"
     wire_type = WireType.FIXED64  # Uses wire type 1 according to protobuf spec
 
@@ -631,10 +646,12 @@ class DoubleType(FixedSizeTypeMixin, TypeInfo):
 class FloatType(FixedSizeTypeMixin, TypeInfo):
     cpp_type = "float"
     default_value = "0.0f"
-    decode_32bit = "value.as_float()"
+    decode_expr = "value.as_float()"
     encode_func = "encode_float"
     wire_type = WireType.FIXED32  # Uses wire type 5
 
+    fixed32_value_template = "float_to_raw({value})"
+
     def dump(self, name: str) -> str:
         o = f'snprintf(buffer, sizeof(buffer), "%g", {name});\n'
         o += "out.append(buffer);"
@@ -658,7 +675,7 @@ class Int64Type(VarintTypeMixin, TypeInfo):
     cpp_type = "int64_t"
     _varint_max_bits = 64
     default_value = "0"
-    decode_varint = "static_cast<int64_t>(value)"
+    decode_expr = "static_cast<int64_t>(value.as_varint())"
     encode_func = "encode_int64"
     wire_type = WireType.VARINT  # Uses wire type 0
 
@@ -679,7 +696,7 @@ class UInt64Type(VarintTypeMixin, TypeInfo):
     cpp_type = "uint64_t"
     _varint_max_bits = 64
     default_value = "0"
-    decode_varint = "value"
+    decode_expr = "value.as_varint()"
     encode_func = "encode_uint64"
     wire_type = WireType.VARINT  # Uses wire type 0
 
@@ -697,11 +714,11 @@ class UInt64Type(VarintTypeMixin, TypeInfo):
         return self._get_simple_size_calculation(name, force, "uint64")
 
     @property
-    def RAW_ENCODE_MAP(self) -> dict[str, str]:  # noqa: N802
+    def RAW_ENCODE_MAP(self) -> dict[str, tuple[str, str]]:  # noqa: N802
         if self.mac_address:
             return {
                 **TypeInfo.RAW_ENCODE_MAP,
-                "encode_uint64": "ProtoEncode::encode_varint_raw_48bit(pos, {value});",
+                "encode_uint64": ("encode_varint_raw_48bit", "{value}"),
             }
         return TypeInfo.RAW_ENCODE_MAP
 
@@ -714,7 +731,7 @@ class Int32Type(VarintTypeMixin, TypeInfo):
     cpp_type = "int32_t"
     _varint_max_bits = 64  # int32 is sign-extended to 64 bits in protobuf
     default_value = "0"
-    decode_varint = "static_cast<int32_t>(value)"
+    decode_expr = "static_cast<int32_t>(value.as_varint())"
     encode_func = "encode_int32"
     wire_type = WireType.VARINT  # Uses wire type 0
 
@@ -734,7 +751,6 @@ class Int32Type(VarintTypeMixin, TypeInfo):
 class Fixed64Type(FixedSizeTypeMixin, TypeInfo):
     cpp_type = "uint64_t"
     default_value = "0"
-    decode_64bit = "value.as_fixed64()"
     encode_func = "encode_fixed64"
     wire_type = WireType.FIXED64  # Uses wire type 1
 
@@ -760,7 +776,7 @@ class Fixed64Type(FixedSizeTypeMixin, TypeInfo):
 class Fixed32Type(FixedSizeTypeMixin, TypeInfo):
     cpp_type = "uint32_t"
     default_value = "0"
-    decode_32bit = "value.as_fixed32()"
+    decode_expr = "value.as_fixed32()"
     encode_func = "encode_fixed32"
     wire_type = WireType.FIXED32  # Uses wire type 5
 
@@ -769,15 +785,7 @@ class Fixed32Type(FixedSizeTypeMixin, TypeInfo):
         o += "out.append(buffer);"
         return o
 
-    @property
-    def encode_content(self) -> str:
-        tag = self.calculate_tag()
-        if self.force and tag < 128:
-            # Emit combined tag+value write: precomputed tag + direct memcpy
-            return f"ProtoEncode::write_tag_and_fixed32(pos, {tag}, this->{self.field_name});"
-        if self.force:
-            return f"ProtoEncode::{self.encode_func}(pos, {self.number}, this->{self.field_name}, true);"
-        return f"ProtoEncode::{self.encode_func}(pos, {self.number}, this->{self.field_name});"
+    fixed32_value_template = "{value}"
 
     def get_size_calculation(self, name: str, force: bool = False) -> str:
         field_id_size = self.calculate_field_id_size()
@@ -797,7 +805,7 @@ class BoolType(VarintTypeMixin, TypeInfo):
     _varint_max_bits = 1
     cpp_type = "bool"
     default_value = "false"
-    decode_varint = "value != 0"
+    decode_expr = "value.as_bool()"
     encode_func = "encode_bool"
     wire_type = WireType.VARINT  # Uses wire type 0
 
@@ -817,7 +825,7 @@ class StringType(TypeInfo):
     default_value = ""
     reference_type = "std::string &"
     const_reference_type = "const std::string &"
-    decode_length = "value.as_string()"
+    decode_expr = "value.as_string()"
     encode_func = "encode_string"
     wire_type = WireType.LENGTH_DELIMITED  # Uses wire type 2
 
@@ -851,9 +859,12 @@ class StringType(TypeInfo):
             f"this->{self.field_name}_ref_.size()",
         ):
             return result
-        if self.force:
-            return f"ProtoEncode::encode_string(pos, {self.number}, this->{self.field_name}_ref_, true);"
-        return f"ProtoEncode::encode_string(pos, {self.number}, this->{self.field_name}_ref_);"
+        return _encode_call(
+            "encode_string",
+            str(self.number),
+            f"this->{self.field_name}_ref_",
+            force=self.force,
+        )
 
     def dump(self, name):
         # If name is 'it', this is a repeated field element - always use string
@@ -929,6 +940,9 @@ class MessageType(TypeInfo):
     def can_use_dump_field(cls) -> bool:
         return False
 
+    def encode_element(self, number: int, element: str) -> str:
+        return _encode_call("encode_sub_message", "buffer", str(number), element)
+
     @property
     def cpp_type(self) -> str:
         return self._field.type_name[1:]
@@ -951,15 +965,9 @@ class MessageType(TypeInfo):
     @property
     def encode_content(self) -> str:
         # Sub-message encoding needs buffer for backpatch/sync
-        return f"ProtoEncode::{self.encode_func}(pos, buffer, {self.number}, this->{self.field_name});"
-
-    @property
-    def decode_length(self) -> str:
-        # Override to return None for message types because we can't use template-based
-        # decoding when the specific message type isn't known at compile time.
-        # Instead, we use the non-template decode_to_message() method which allows
-        # runtime polymorphism through virtual function calls.
-        return None
+        return _encode_call(
+            self.encode_func, "buffer", str(self.number), f"this->{self.field_name}"
+        )
 
     @property
     def public_content(self) -> list[str]:
@@ -976,19 +984,14 @@ class MessageType(TypeInfo):
         )
 
     @property
-    def decode_length_content(self) -> str:
-        # Custom decode that doesn't use templates
+    def decode_content(self) -> str:
+        body = f"value.decode_to_message(this->{self.field_name});"
         if self._track_presence:
             # decode_to_message() cannot report failure, so setting the flag
             # afterwards only documents intent; a status-returning decode could
             # gate it for real without touching callers.
-            return (
-                f"case {self.number}:\n"
-                f"      value.decode_to_message(this->{self.field_name});\n"
-                f"      this->has_{self.name} = true;\n"
-                f"      break;"
-            )
-        return f"case {self.number}: value.decode_to_message(this->{self.field_name}); break;"
+            body += f"\nthis->has_{self.name} = true;"
+        return self.decode_case(body)
 
     def dump(self, name: str) -> str:
         return f"{name}.dump_to(out);"
@@ -1027,7 +1030,7 @@ class BytesType(TypeInfo):
     reference_type = "std::string &"
     const_reference_type = "const std::string &"
     encode_func = "encode_bytes"
-    decode_length = "value.as_string()"
+    decode_expr = "value.as_string()"
     wire_type = WireType.LENGTH_DELIMITED  # Uses wire type 2
 
     @property
@@ -1058,9 +1061,13 @@ class BytesType(TypeInfo):
             f"this->{self.field_name}_ptr_", f"this->{self.field_name}_len_"
         ):
             return result
-        if self.force:
-            return f"ProtoEncode::encode_bytes(pos, {self.number}, this->{self.field_name}_ptr_, this->{self.field_name}_len_, true);"
-        return f"ProtoEncode::encode_bytes(pos, {self.number}, this->{self.field_name}_ptr_, this->{self.field_name}_len_);"
+        return _encode_call(
+            "encode_bytes",
+            str(self.number),
+            f"this->{self.field_name}_ptr_",
+            f"this->{self.field_name}_len_",
+            force=self.force,
+        )
 
     def dump(self, name: str) -> str:
         ptr_dump = f"format_hex_pretty(this->{self.field_name}_ptr_, this->{self.field_name}_len_)"
@@ -1127,16 +1134,12 @@ class PointerToBufferTypeBase(TypeInfo):
     def can_use_dump_field(cls) -> bool:
         return False
 
+    # Only here to make needs_decode required: the null string default keys off it, so a call
+    # site must not fall back on the base class default
     def __init__(
-        self, field: descriptor.FieldDescriptorProto, size: int | None = None
+        self, field: descriptor.FieldDescriptorProto, needs_decode: bool
     ) -> None:
-        super().__init__(field)
-        self.array_size = 0
-
-    @property
-    def decode_length(self) -> str | None:
-        # This is handled in decode_length_content
-        return None
+        super().__init__(field, needs_decode)
 
     @property
     def wire_type(self) -> WireType:
@@ -1170,17 +1173,20 @@ class PointerToBytesBufferType(PointerToBufferTypeBase):
             f"this->{self.field_name}", f"this->{self.field_name}_len"
         ):
             return result
-        if self.force:
-            return f"ProtoEncode::encode_bytes(pos, {self.number}, this->{self.field_name}, this->{self.field_name}_len, true);"
-        return f"ProtoEncode::encode_bytes(pos, {self.number}, this->{self.field_name}, this->{self.field_name}_len);"
+        return _encode_call(
+            "encode_bytes",
+            str(self.number),
+            f"this->{self.field_name}",
+            f"this->{self.field_name}_len",
+            force=self.force,
+        )
 
     @property
-    def decode_length_content(self) -> str | None:
-        return f"""case {self.number}: {{
-      this->{self.field_name} = value.data();
-      this->{self.field_name}_len = value.size();
-      break;
-    }}"""
+    def decode_content(self) -> str:
+        return self.decode_case(
+            f"this->{self.field_name} = value.data();\n"
+            f"this->{self.field_name}_len = value.size();",
+        )
 
     def dump(self, name: str) -> str:
         return (
@@ -1214,34 +1220,53 @@ class PointerToStringBufferType(PointerToBufferTypeBase):
     def can_use_dump_field(cls) -> bool:
         return True
 
+    @property
+    def _starts_null(self) -> bool:
+        """A field that is only encoded, and skipped when empty, never has its pointer read
+        before it is set, so it can default to a null StringRef and the message constructs as
+        one zero fill. Any encode path that copies unconditionally must check this."""
+        return not self._needs_decode and not self.force
+
     @property
     def public_content(self) -> list[str]:
+        if self._starts_null:
+            return [
+                f"StringRef {self.field_name}{{nullptr, 0}};  // null until set, encode only"
+            ]
         return [f"StringRef {self.field_name}{{}};"]
 
     @property
     def encode_content(self) -> str:
         max_len = self.max_data_length
         if max_len is not None and max_len < 128 and self.force:
+            assert not self._starts_null, (
+                "unconditional copy of a field that may start null"
+            )
             tag = self.calculate_tag()
             if tag < 128:
-                return f"ProtoEncode::encode_short_string_force(pos, {tag}, this->{self.field_name});"
+                return _encode_call(
+                    "encode_short_string_force", str(tag), f"this->{self.field_name}"
+                )
         if result := self._encode_bytes_with_precomputed_tag(
             f"this->{self.field_name}.c_str()",
             f"this->{self.field_name}.size()",
         ):
+            assert not self._starts_null, (
+                "unconditional copy of a field that may start null"
+            )
             return result
-        if self.force:
-            return f"ProtoEncode::encode_string(pos, {self.number}, this->{self.field_name}, true);"
-        return (
-            f"ProtoEncode::encode_string(pos, {self.number}, this->{self.field_name});"
+        return _encode_call(
+            "encode_string",
+            str(self.number),
+            f"this->{self.field_name}",
+            force=self.force,
         )
 
     @property
-    def decode_length_content(self) -> str | None:
-        return f"""case {self.number}: {{
-      this->{self.field_name} = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
-      break;
-    }}"""
+    def decode_content(self) -> str:
+        return self.decode_case(
+            f"this->{self.field_name} = StringRef(value.data(), value.size());",
+        )
 
     def dump(self, name: str) -> str:
         # Not used since we use dump_field, but required by abstract base class
@@ -1310,14 +1335,13 @@ class PackedBufferTypeInfo(TypeInfo):
         ]
 
     @property
-    def decode_length_content(self) -> str:
+    def decode_content(self) -> str:
         """Store pointer to buffer and calculate count of packed varints."""
-        return f"""case {self.number}: {{
-      this->{self.field_name}_data_ = value.data();
-      this->{self.field_name}_length_ = value.size();
-      this->{self.field_name}_count_ = count_packed_varints(value.data(), value.size());
-      break;
-    }}"""
+        return self.decode_case(
+            f"this->{self.field_name}_data_ = value.data();\n"
+            f"this->{self.field_name}_length_ = value.size();\n"
+            f"this->{self.field_name}_count_ = count_packed_varints(value.data(), value.size());",
+        )
 
     @property
     def encode_content(self) -> str:
@@ -1402,17 +1426,11 @@ class FixedArrayBytesType(TypeInfo):
         ]
 
     @property
-    def decode_length_content(self) -> str:
-        o = f"case {self.number}: {{\n"
-        o += "  const std::string &data_str = value.as_string();\n"
-        o += f"  this->{self.field_name}_len = data_str.size();\n"
-        o += f"  if (this->{self.field_name}_len > {self.array_size}) {{\n"
-        o += f"    this->{self.field_name}_len = {self.array_size};\n"
-        o += "  }\n"
-        o += f"  memcpy(this->{self.field_name}, data_str.data(), this->{self.field_name}_len);\n"
-        o += "  break;\n"
-        o += "}"
-        return o
+    def decode_content(self) -> str:
+        return self.decode_case(
+            f"this->{self.field_name}_len = std::min<size_t>(value.size(), {self.array_size});\n"
+            f"memcpy(this->{self.field_name}, value.data(), this->{self.field_name}_len);",
+        )
 
     @property
     def encode_content(self) -> str:
@@ -1421,9 +1439,13 @@ class FixedArrayBytesType(TypeInfo):
             f"this->{self.field_name}", f"this->{self.field_name}_len", max_len=max_len
         ):
             return result
-        if self.force:
-            return f"ProtoEncode::encode_bytes(pos, {self.number}, this->{self.field_name}, this->{self.field_name}_len, true);"
-        return f"ProtoEncode::encode_bytes(pos, {self.number}, this->{self.field_name}, this->{self.field_name}_len);"
+        return _encode_call(
+            "encode_bytes",
+            str(self.number),
+            f"this->{self.field_name}",
+            f"this->{self.field_name}_len",
+            force=self.force,
+        )
 
     def dump(self, name: str) -> str:
         return f"out.append(format_hex_pretty({name}, {name}_len));"
@@ -1471,7 +1493,7 @@ class UInt32Type(VarintTypeMixin, TypeInfo):
     cpp_type = "uint32_t"
     _varint_max_bits = 32
     default_value = "0"
-    decode_varint = "value"
+    decode_expr = "value.as_varint()"
     encode_func = "encode_uint32"
     wire_type = WireType.VARINT  # Uses wire type 0
 
@@ -1494,13 +1516,21 @@ class UInt32Type(VarintTypeMixin, TypeInfo):
 class EnumType(VarintTypeMixin, TypeInfo):
     _varint_max_bits = 32
 
+    def encode_element(self, number: int, element: str) -> str:
+        return _encode_call(
+            self.encode_func,
+            str(number),
+            f"static_cast<uint32_t>({element})",
+            force=True,
+        )
+
     @property
     def cpp_type(self) -> str:
         return f"enums::{self._field.type_name[1:]}"
 
     @property
-    def decode_varint(self) -> str:
-        return f"static_cast<{self.cpp_type}>(value)"
+    def decode_expr(self) -> str:
+        return f"static_cast<{self.cpp_type}>(value.as_varint())"
 
     default_value = ""
     wire_type = WireType.VARINT  # Uses wire type 0
@@ -1520,9 +1550,9 @@ class EnumType(VarintTypeMixin, TypeInfo):
     @property
     def encode_content(self) -> str:
         value_expr = f"static_cast<uint32_t>(this->{self.field_name})"
-        if self.force:
-            return f"ProtoEncode::{self.encode_func}(pos, {self.number}, {value_expr}, true);"
-        return f"ProtoEncode::{self.encode_func}(pos, {self.number}, {value_expr});"
+        return _encode_call(
+            self.encode_func, str(self.number), value_expr, force=self.force
+        )
 
     def dump(self, name: str) -> str:
         return f"out.append_p(proto_enum_to_string<{self.cpp_type}>({name}));"
@@ -1547,7 +1577,7 @@ class EnumType(VarintTypeMixin, TypeInfo):
 class SFixed32Type(FixedSizeTypeMixin, TypeInfo):
     cpp_type = "int32_t"
     default_value = "0"
-    decode_32bit = "value.as_sfixed32()"
+    decode_expr = "value.as_sfixed32()"
     encode_func = "encode_sfixed32"
     wire_type = WireType.FIXED32  # Uses wire type 5
 
@@ -1573,7 +1603,6 @@ class SFixed32Type(FixedSizeTypeMixin, TypeInfo):
 class SFixed64Type(FixedSizeTypeMixin, TypeInfo):
     cpp_type = "int64_t"
     default_value = "0"
-    decode_64bit = "value.as_sfixed64()"
     encode_func = "encode_sfixed64"
     wire_type = WireType.FIXED64  # Uses wire type 1
 
@@ -1600,7 +1629,7 @@ class SInt32Type(VarintTypeMixin, TypeInfo):
     cpp_type = "int32_t"
     _varint_max_bits = 32  # zigzag encoding keeps it 32-bit
     default_value = "0"
-    decode_varint = "decode_zigzag32(static_cast<uint32_t>(value))"
+    decode_expr = "decode_zigzag32(static_cast<uint32_t>(value.as_varint()))"
     encode_func = "encode_sint32"
     wire_type = WireType.VARINT  # Uses wire type 0
 
@@ -1621,7 +1650,7 @@ class SInt64Type(VarintTypeMixin, TypeInfo):
     cpp_type = "int64_t"
     _varint_max_bits = 64
     default_value = "0"
-    decode_varint = "decode_zigzag64(value)"
+    decode_expr = "decode_zigzag64(value.as_varint())"
     encode_func = "encode_sint64"
     wire_type = WireType.VARINT  # Uses wire type 0
 
@@ -1701,9 +1730,9 @@ def _generate_inline_encode_block(
 
     lines = []
     lines.append(f"auto &sub_msg = {element};")
-    lines.append(f"ProtoEncode::write_raw_byte(pos, {tag});")
+    lines.append(_encode_call("write_raw_byte", str(tag)))
     lines.append("uint8_t *len_pos = pos;")
-    lines.append("ProtoEncode::reserve_byte(pos);")
+    lines.append(_encode_call("reserve_byte"))
 
     # Generate inline field encoding for each sub-message field
     for field in sub_desc.field:
@@ -1774,18 +1803,11 @@ class FixedArrayRepeatedType(TypeInfo):
 
     def _encode_element(self, element: str) -> str:
         """Helper to generate encode statement for a single element."""
-        if isinstance(self._ti, EnumType):
-            return f"ProtoEncode::{self._ti.encode_func}(pos, {self.number}, static_cast<uint32_t>({element}), true);"
-        # Repeated message elements use encode_sub_message (force=true is default)
-        if isinstance(self._ti, MessageType):
-            if _is_inline_encode(self._ti.cpp_type):
-                return _generate_inline_encode_block(
-                    self.number, self._ti.cpp_type, element
-                )
-            return f"ProtoEncode::encode_sub_message(pos, buffer, {self.number}, {element});"
-        return (
-            f"ProtoEncode::{self._ti.encode_func}(pos, {self.number}, {element}, true);"
-        )
+        if isinstance(self._ti, MessageType) and _is_inline_encode(self._ti.cpp_type):
+            return _generate_inline_encode_block(
+                self.number, self._ti.cpp_type, element
+            )
+        return self._ti.encode_element(self.number, element)
 
     @property
     def cpp_type(self) -> str:
@@ -2079,55 +2101,23 @@ class RepeatedTypeInfo(TypeInfo):
         return self._ti.wire_type
 
     @property
-    def decode_varint_content(self) -> str:
-        # Pointer fields don't support decoding
-        if self._use_pointer:
-            return None
-        content = self._ti.decode_varint
-        if content is None:
-            return None
-        return (
-            f"case {self.number}: this->{self.field_name}.push_back({content}); break;"
-        )
+    def decode_expr(self) -> str | None:
+        return self._ti.decode_expr
+
+    def _decode_store(self, expr: str) -> str:
+        return f"this->{self.field_name}.push_back({expr});"
 
     @property
-    def decode_length_content(self) -> str:
+    def decode_content(self) -> str | None:
         # Pointer fields don't support decoding
         if self._use_pointer:
             return None
-        content = self._ti.decode_length
-        if content is None and isinstance(self._ti, MessageType):
-            # Special handling for non-template message decoding
-            return f"case {self.number}: this->{self.field_name}.emplace_back(); value.decode_to_message(this->{self.field_name}.back()); break;"
-        if content is None:
-            return None
-        return (
-            f"case {self.number}: this->{self.field_name}.push_back({content}); break;"
-        )
-
-    @property
-    def decode_32bit_content(self) -> str:
-        # Pointer fields don't support decoding
-        if self._use_pointer:
-            return None
-        content = self._ti.decode_32bit
-        if content is None:
-            return None
-        return (
-            f"case {self.number}: this->{self.field_name}.push_back({content}); break;"
-        )
-
-    @property
-    def decode_64bit_content(self) -> str:
-        # Pointer fields don't support decoding
-        if self._use_pointer:
-            return None
-        content = self._ti.decode_64bit
-        if content is None:
-            return None
-        return (
-            f"case {self.number}: this->{self.field_name}.push_back({content}); break;"
-        )
+        if isinstance(self._ti, MessageType):
+            return self.decode_case(
+                f"this->{self.field_name}.emplace_back();\n"
+                f"value.decode_to_message(this->{self.field_name}.back());"
+            )
+        return super().decode_content
 
     @property
     def _ti_is_bool(self) -> bool:
@@ -2135,15 +2125,7 @@ class RepeatedTypeInfo(TypeInfo):
         return isinstance(self._ti, BoolType)
 
     def _encode_element_call(self, element: str) -> str:
-        """Helper to generate encode call for a single element."""
-        if isinstance(self._ti, EnumType):
-            return f"ProtoEncode::{self._ti.encode_func}(pos, {self.number}, static_cast<uint32_t>({element}), true);"
-        # Repeated message elements use encode_sub_message (force=true is default)
-        if isinstance(self._ti, MessageType):
-            return f"ProtoEncode::encode_sub_message(pos, buffer, {self.number}, {element});"
-        return (
-            f"ProtoEncode::{self._ti.encode_func}(pos, {self.number}, {element}, true);"
-        )
+        return self._ti.encode_element(self.number, element)
 
     @property
     def encode_content(self) -> str:
@@ -2152,7 +2134,7 @@ class RepeatedTypeInfo(TypeInfo):
             # Special handling for const char* elements (when container_no_template contains "const char")
             if "const char" in self._container_no_template:
                 o = f"for (const char *it : *this->{self.field_name}) {{\n"
-                o += f"  ProtoEncode::{self._ti.encode_func}(pos, {self.number}, it, strlen(it), true);\n"
+                o += f"  {_encode_call(self._ti.encode_func, str(self.number), 'it', 'strlen(it)', force=True)}\n"
             else:
                 o = f"for (const auto &it : *this->{self.field_name}) {{\n"
                 o += f"  {self._encode_element_call('it')}\n"
@@ -2538,10 +2520,7 @@ def build_message_type(
 ) -> tuple[str, str, str]:
     public_content: list[str] = []
     protected_content: list[str] = []
-    decode_varint: list[str] = []
-    decode_length: list[str] = []
-    decode_32bit: list[str] = []
-    decode_64bit: list[str] = []
+    decode: list[str] = []
     encode: list[str] = []
     dump: list[str] = []
     size_calc: list[str] = []
@@ -2557,8 +2536,8 @@ def build_message_type(
 
     # Get source direction to determine if we need decode/encode methods
     source = message_source_map[desc.name]
-    needs_decode = source in (SOURCE_BOTH, SOURCE_CLIENT)
-    needs_encode = source in (SOURCE_BOTH, SOURCE_SERVER)
+    needs_decode = message_needs_decode(source)
+    needs_encode = message_needs_encode(source)
 
     # Add MESSAGE_TYPE method if this is a service message
     if message_id is not None:
@@ -2670,22 +2649,8 @@ def build_message_type(
             if field.options.HasExtension(pb.field_ifdef):
                 field_ifdef = field.options.Extensions[pb.field_ifdef]
 
-            if ti.decode_varint_content:
-                decode_varint.extend(
-                    wrap_with_ifdef(ti.decode_varint_content, field_ifdef)
-                )
-            if ti.decode_length_content:
-                decode_length.extend(
-                    wrap_with_ifdef(ti.decode_length_content, field_ifdef)
-                )
-            if ti.decode_32bit_content:
-                decode_32bit.extend(
-                    wrap_with_ifdef(ti.decode_32bit_content, field_ifdef)
-                )
-            if ti.decode_64bit_content:
-                decode_64bit.extend(
-                    wrap_with_ifdef(ti.decode_64bit_content, field_ifdef)
-                )
+            if case := ti.decode_content:
+                decode.extend(wrap_with_ifdef(case, field_ifdef))
         if ti.dump_content:
             # Check for field_ifdef option for dump as well
             field_ifdef = None
@@ -2695,50 +2660,23 @@ def build_message_type(
             dump.extend(wrap_with_ifdef(ti.dump_content, field_ifdef))
 
     cpp = ""
-    if decode_varint:
-        o = f"bool {desc.name}::decode_varint(uint32_t field_id, proto_varint_value_t value) {{\n"
-        o += "  switch (field_id) {\n"
-        o += indent("\n".join(decode_varint), "    ") + "\n"
-        o += "    default: return false;\n"
+    if decode:
+        o = f"void {desc.name}::decode_field(void *self, uint32_t tag, const uint8_t *data, proto_varint_value_t scalar) {{\n"
+        o += f"  auto &msg = *static_cast<{desc.name} *>(self);\n"
+        o += "  const ProtoFieldValue value(data, scalar);\n"
+        o += "  switch (tag) {\n"
+        o += indent("\n".join(decode), "    ").replace("this->", "msg.") + "\n"
         o += "  }\n"
-        o += "  return true;\n"
         o += "}\n"
         cpp += o
-        prot = "bool decode_varint(uint32_t field_id, proto_varint_value_t value) override;"
-        protected_content.insert(0, prot)
-    if decode_length:
-        o = f"bool {desc.name}::decode_length(uint32_t field_id, ProtoLengthDelimited value) {{\n"
-        o += "  switch (field_id) {\n"
-        o += indent("\n".join(decode_length), "    ") + "\n"
-        o += "    default: return false;\n"
-        o += "  }\n"
-        o += "  return true;\n"
-        o += "}\n"
-        cpp += o
-        prot = "bool decode_length(uint32_t field_id, ProtoLengthDelimited value) override;"
-        protected_content.insert(0, prot)
-    if decode_32bit:
-        o = f"bool {desc.name}::decode_32bit(uint32_t field_id, Proto32Bit value) {{\n"
-        o += "  switch (field_id) {\n"
-        o += indent("\n".join(decode_32bit), "    ") + "\n"
-        o += "    default: return false;\n"
-        o += "  }\n"
-        o += "  return true;\n"
-        o += "}\n"
-        cpp += o
-        prot = "bool decode_32bit(uint32_t field_id, Proto32Bit value) override;"
-        protected_content.insert(0, prot)
-    if decode_64bit:
-        o = f"bool {desc.name}::decode_64bit(uint32_t field_id, Proto64Bit value) {{\n"
-        o += "  switch (field_id) {\n"
-        o += indent("\n".join(decode_64bit), "    ") + "\n"
-        o += "    default: return false;\n"
-        o += "  }\n"
-        o += "  return true;\n"
-        o += "}\n"
-        cpp += o
-        prot = "bool decode_64bit(uint32_t field_id, Proto64Bit value) override;"
+        prot = "static void decode_field(void *self, uint32_t tag, const uint8_t *data, proto_varint_value_t scalar);"
         protected_content.insert(0, prot)
+        if not fixed_vector_fields:
+            public_content.append(
+                "void decode(const uint8_t *buffer, size_t length) {\n"
+                "  ProtoDecodableMessage::decode_fields(this, buffer, length, &decode_field);\n"
+                "}"
+            )
 
     # Generate custom decode() override for messages with FixedVector fields
     if fixed_vector_fields:
@@ -2748,8 +2686,8 @@ def build_message_type(
         for field_name, field_number in fixed_vector_fields:
             o += f"  uint32_t count_{field_name} = ProtoDecodableMessage::count_repeated_field(buffer, length, {field_number});\n"
             o += f"  this->{field_name}.init(count_{field_name});\n"
-        # Call parent decode to populate the fields
-        o += "  ProtoDecodableMessage::decode(buffer, length);\n"
+        # Then the shared loop fills them
+        o += "  ProtoDecodableMessage::decode_fields(this, buffer, length, &decode_field);\n"
         o += "}\n"
         cpp += o
         # Generate the decode() declaration in header (public method)
@@ -2784,28 +2722,36 @@ def build_message_type(
             )
             for line in encode
         ]
-        o = f"{speed_attr}uint8_t *{desc.name}::encode(ProtoWriteBuffer &buffer PROTO_ENCODE_DEBUG_PARAM) const {{\n"
+        o = f"{speed_attr}uint8_t *{desc.name}::encode_msg(const void *self, ProtoWriteBuffer &buffer PROTO_ENCODE_DEBUG_PARAM) {{\n"
+        o += f"  const auto &msg = *static_cast<const {desc.name} *>(self);\n"
         o += "  uint8_t *__restrict__ pos = buffer.get_pos();\n"
-        o += indent("\n".join(encode_debug)) + "\n"
+        o += indent("\n".join(encode_debug)).replace("this->", "msg.") + "\n"
         o += "  return pos;\n"
         o += "}\n"
         cpp += o
-        prot = (
-            "uint8_t *encode(ProtoWriteBuffer &buffer PROTO_ENCODE_DEBUG_PARAM) const;"
+        public_content.append(
+            "static uint8_t *encode_msg(const void *self, ProtoWriteBuffer &buffer PROTO_ENCODE_DEBUG_PARAM);"
+        )
+        public_content.append(
+            "uint8_t *encode(ProtoWriteBuffer &buffer PROTO_ENCODE_DEBUG_PARAM) const {\n"
+            "  return encode_msg(this, buffer PROTO_ENCODE_DEBUG_ARG);\n"
+            "}"
         )
-        public_content.append(prot)
     # If no fields to encode or message doesn't need encoding, the default implementation in ProtoMessage will be used
 
     # Add calculate_size method only if this message needs encoding and has fields
     if needs_encode and size_calc and not is_inline_only:
-        o = f"{speed_attr}uint32_t {desc.name}::calculate_size() const {{\n"
+        o = f"{speed_attr}uint32_t {desc.name}::calc_size_msg(const void *self) {{\n"
+        o += f"  const auto &msg = *static_cast<const {desc.name} *>(self);\n"
         o += "  uint32_t size = 0;\n"
-        o += indent("\n".join(size_calc)) + "\n"
+        o += indent("\n".join(size_calc)).replace("this->", "msg.") + "\n"
         o += "  return size;\n"
         o += "}\n"
         cpp += o
-        prot = "uint32_t calculate_size() const;"
-        public_content.append(prot)
+        public_content.append("static uint32_t calc_size_msg(const void *self);")
+        public_content.append(
+            "uint32_t calculate_size() const { return calc_size_msg(this); }"
+        )
     # If no fields to calculate size for or message doesn't need encoding, the default implementation in ProtoMessage will be used
 
     # dump_to method declaration in header
@@ -2900,6 +2846,23 @@ def get_field_opt(
     return field.options.Extensions[opt]
 
 
+def message_needs_decode(source: int) -> bool:
+    return source in (SOURCE_BOTH, SOURCE_CLIENT)
+
+
+def message_needs_encode(source: int) -> bool:
+    return source in (SOURCE_BOTH, SOURCE_SERVER)
+
+
+def is_decodable_class(desc: descriptor.DescriptorProto, source: int) -> bool:
+    """Whether the generated class derives from ProtoDecodableMessage: decoded, and either on a
+    decodable base class or with at least one live field."""
+    return message_needs_decode(source) and (
+        get_base_class(desc) is not None
+        or any(not field.options.deprecated for field in desc.field)
+    )
+
+
 def get_base_class(desc: descriptor.DescriptorProto) -> str | None:
     """Get the base_class option from a message descriptor."""
     if not desc.options.HasExtension(pb.base_class):
@@ -3001,11 +2964,11 @@ def build_base_class(
 
     # Determine if any message using this base class needs decoding/encoding
     needs_decode = any(
-        message_source_map.get(msg.name, SOURCE_BOTH) in (SOURCE_BOTH, SOURCE_CLIENT)
+        message_needs_decode(message_source_map.get(msg.name, SOURCE_BOTH))
         for msg in messages
     )
     needs_encode = any(
-        message_source_map.get(msg.name, SOURCE_BOTH) in (SOURCE_BOTH, SOURCE_SERVER)
+        message_needs_encode(message_source_map.get(msg.name, SOURCE_BOTH))
         for msg in messages
     )
 
@@ -3439,6 +3402,7 @@ static void dump_bytes_field(DumpBuffer &out, const char *field_name, const uint
 
     # Generate message types with base class information
     # Simple grouping by ifdef
+    decodable_messages: list[tuple[str, str | None]] = []
     current_ifdef = None
 
     for m in mt:
@@ -3455,6 +3419,8 @@ static void dump_bytes_field(DumpBuffer &out, const char *field_name, const uint
             continue
 
         s, c, dc = build_message_type(m, base_class_fields, message_source_map)
+        if is_decodable_class(m, message_source_map[m.name]):
+            decodable_messages.append((m.name, message_ifdef_map.get(m.name)))
         msg_ifdef = message_ifdef_map.get(m.name)
 
         # Handle ifdef changes
@@ -3481,6 +3447,22 @@ static void dump_bytes_field(DumpBuffer &out, const char *field_name, const uint
         cpp += "#endif\n"
         dump_cpp += "#endif\n"
 
+    # decode() passes decode_field explicitly, so without the dump virtuals no decodable message
+    # may carry a vtable; a build at any level below VERY_VERBOSE proves it
+    cpp += "#ifndef HAS_PROTO_MESSAGE_DUMP\n"
+    assert_ifdef = None
+    for name, msg_ifdef in decodable_messages:
+        if msg_ifdef != assert_ifdef:
+            if assert_ifdef is not None:
+                cpp += "#endif\n"
+            if msg_ifdef is not None:
+                cpp += _make_ifdef_line(msg_ifdef) + "\n"
+            assert_ifdef = msg_ifdef
+        cpp += f'static_assert(!std::is_polymorphic_v<{name}>, "decodable messages carry no vtable");\n'
+    if assert_ifdef is not None:
+        cpp += "#endif\n"
+    cpp += "#endif\n"
+
     content += """\
 
 }  // namespace esphome::api

tests/benchmarks/components/api/bench_proto_proxy.cpp

@@ -249,7 +249,7 @@ static APIBuffer build_infrared_rf_transmit_wire() {
   std::memcpy(bytes + len, packed, packed_len);
   len += packed_len;
   // field 6: modulation = 1 (non-zero so it's actually emitted and exercises
-  // decode_varint for this field, matching the documented layout above).
+  // decode_field for this field, matching the documented layout above).
   put_byte(0x30);
   put_varint(1);
 

tests/component_tests/remote_receiver/config/receiver_bare.yaml

@@ -1,9 +0,0 @@
-esphome:
-  name: test
-
-esp32:
-  board: esp32dev
-
-remote_receiver:
-  - id: rcvr
-    pin: GPIO4

tests/component_tests/remote_receiver/config/receiver_with_dumpers.yaml

@@ -1,24 +0,0 @@
-esphome:
-  name: test
-
-esp32:
-  board: esp32dev
-
-logger:
-
-remote_receiver:
-  - id: rcvr
-    pin: GPIO4
-    dump:
-      - nec
-      - rc_switch
-    on_nec:
-      then:
-        - logger.log: nec
-
-binary_sensor:
-  - platform: remote_receiver
-    name: Remote Input
-    nec:
-      address: 0x1234
-      command: 0x5678

tests/component_tests/remote_receiver/config/receiver_with_proxies.yaml

@@ -1,20 +0,0 @@
-esphome:
-  name: test
-
-esp32:
-  board: esp32dev
-
-remote_receiver:
-  - id: rcvr
-    pin: GPIO4
-
-infrared:
-  - platform: ir_rf_proxy
-    name: IR Receiver
-    remote_receiver_id: rcvr
-
-radio_frequency:
-  - platform: ir_rf_proxy
-    name: RF Receiver
-    frequency: 433.92MHz
-    remote_receiver_id: rcvr

tests/component_tests/remote_receiver/test_slot_counts.py

@@ -1,82 +0,0 @@
-"""Listener and dumper StaticVector sizes come from codegen slot counts."""
-
-from collections.abc import Callable
-from pathlib import Path
-
-import pytest
-
-from esphome.components import remote_base
-import esphome.config_validation as cv
-
-from ..helpers import get_define_value
-
-
-def test_dumper_and_listener_counts(
-    generate_main: Callable[[str | Path], str],
-    component_config_path: Callable[[str], Path],
-) -> None:
-    generate_main(component_config_path("receiver_with_dumpers.yaml"))
-    # nec and rc_switch dumpers
-    assert get_define_value("REMOTE_BASE_DUMPER_COUNT") == "2"
-    # on_nec trigger plus the remote_receiver binary sensor
-    assert get_define_value("REMOTE_BASE_LISTENER_COUNT") == "2"
-
-
-def test_bare_receiver_emits_no_counts(
-    generate_main: Callable[[str | Path], str],
-    component_config_path: Callable[[str], Path],
-) -> None:
-    generate_main(component_config_path("receiver_bare.yaml"))
-    assert get_define_value("REMOTE_BASE_DUMPER_COUNT") is None
-    assert get_define_value("REMOTE_BASE_LISTENER_COUNT") is None
-
-
-def test_proxy_receivers_count_as_listeners(
-    generate_main: Callable[[str | Path], str],
-    component_config_path: Callable[[str], Path],
-) -> None:
-    generate_main(component_config_path("receiver_with_proxies.yaml"))
-    # infrared and radio_frequency ir_rf_proxy platforms each listen
-    assert get_define_value("REMOTE_BASE_LISTENER_COUNT") == "2"
-    assert get_define_value("REMOTE_BASE_DUMPER_COUNT") is None
-
-
-def test_only_used_protocol_sources_are_compiled(
-    generate_main: Callable[[str | Path], str],
-    component_config_path: Callable[[str], Path],
-) -> None:
-    generate_main(component_config_path("receiver_with_dumpers.yaml"))
-    excluded = set(remote_base.FILTER_SOURCE_FILES())
-    assert "nec_protocol.cpp" not in excluded
-    assert "rc_switch_protocol.cpp" not in excluded
-    assert "sony_protocol.cpp" in excluded
-    assert "remote_base.cpp" not in excluded
-
-
-def test_every_registry_name_maps_to_a_protocol_source() -> None:
-    sources = {
-        path.name for path in Path(remote_base.__file__).parent.glob("*_protocol.cpp")
-    }
-    names = (
-        set(remote_base.BINARY_SENSOR_REGISTRY)
-        | set(remote_base.DUMPER_REGISTRY)
-        | {key.removeprefix("on_") for key in remote_base.TRIGGER_REGISTRY}
-    )
-    for name in names:
-        stem = (
-            remote_base.protocol_define(name)
-            .removeprefix("USE_REMOTE_PROTOCOL_")
-            .lower()
-        )
-        assert f"{stem}_protocol.cpp" in sources, name
-
-
-def test_dump_list_is_deduplicated_across_forms() -> None:
-    dumpers = remote_base.validate_dumpers(["raw", {"raw": None}, "nec", "nec"])
-    assert [name for name, _ in dumpers] == ["raw", "nec"]
-
-
-@pytest.mark.parametrize("bad", [["nec", None], [5]])
-def test_dump_list_rejects_invalid_entries_with_a_validation_error(bad: list) -> None:
-    with pytest.raises(cv.Invalid):
-        remote_base.validate_dumpers(bad)

tests/components/api/test_proto_mac_varint.cpp

@@ -59,7 +59,7 @@ static void verify_mac(uint64_t mac, size_t expected_bytes) {
 #ifdef ESPHOME_DEBUG_API
   uint8_t *proto_debug_end_ = api_buf.data() + api_buf.size();
 #endif
-  ProtoEncode::encode_varint_raw_48bit(pos PROTO_ENCODE_DEBUG_ARG, mac);
+  pos = ProtoEncode::encode_varint_raw_48bit(pos PROTO_ENCODE_DEBUG_ARG, mac);
   size_t new_len = pos - api_buf.data();
 
   EXPECT_EQ(new_len, expected_bytes) << "mac=0x" << std::hex << mac << std::dec;

tests/components/core/test_string_ref.cpp

@@ -59,4 +59,47 @@ TEST(StringRefStartsWith, RefOverloadComparesOnlyTheViewedLength) {
   EXPECT_TRUE(ref.starts_with(prefix));
 }
 
+// The generated api messages start their encode only string fields as a null pointer with zero
+// length; every member must treat that exactly like the default constructed empty string.
+TEST(StringRefNullEmpty, BehavesAsEmptyString) {
+  const StringRef null_empty{nullptr, 0};
+  const StringRef empty;
+  EXPECT_TRUE(null_empty.empty());
+  EXPECT_EQ(null_empty.size(), 0u);
+  EXPECT_EQ(null_empty.c_str(), nullptr);
+  EXPECT_TRUE(null_empty == empty);
+  EXPECT_TRUE(null_empty == "");
+  EXPECT_TRUE(null_empty == std::string());
+  EXPECT_EQ(null_empty.compare(empty), 0);
+  EXPECT_EQ(null_empty.compare(""), 0);
+  EXPECT_LT(null_empty.compare("a"), 0);
+  EXPECT_TRUE(null_empty.starts_with(""));
+  EXPECT_FALSE(null_empty.starts_with("a"));
+  EXPECT_EQ(null_empty.str(), std::string());
+  EXPECT_EQ(null_empty.substr(0), std::string());
+  EXPECT_EQ(null_empty.find('a'), std::string::npos);
+  EXPECT_EQ(null_empty.find("a"), std::string::npos);
+  char buf[4] = "xyz";
+  EXPECT_EQ(null_empty.copy(buf, sizeof(buf)), 0u);
+  EXPECT_EQ(null_empty.begin(), null_empty.end());
+}
+
+TEST(StringRefNullEmpty, ComparesAgainstText) {
+  const StringRef null_empty{nullptr, 0};
+  const StringRef text("abc", 3);
+  EXPECT_FALSE(null_empty == text);
+  EXPECT_FALSE(text == null_empty);
+  EXPECT_LT(null_empty.compare(text), 0);
+  EXPECT_GT(text.compare(null_empty), 0);
+  EXPECT_TRUE(text.starts_with(null_empty));
+}
+
+TEST(StringRefNullEmpty, TwoNullViewsAreEqual) {
+  const StringRef a{nullptr, 0};
+  const StringRef b{nullptr, 0};
+  EXPECT_TRUE(a == b);
+  EXPECT_EQ(a.compare(b), 0);
+  EXPECT_TRUE(a.starts_with(b));
+}
+
 }  // namespace esphome::core::testing

tests/components/remote_receiver/bare-common.yaml

@@ -1,6 +0,0 @@
-# A receiver with no dumpers and no listeners compiles both lists out.
-# Only built while remote_receiver is tested in isolation: the counts are global defines,
-# so this variant cannot be merged with configs that register any.
-remote_receiver:
-  - id: rcvr_bare
-    pin: ${pin}

tests/components/remote_receiver/test-bare.esp32-idf.yaml

@@ -1,5 +0,0 @@
-substitutions:
-  pin: GPIO2
-
-packages:
-  bare: !include bare-common.yaml

tests/integration/fixtures/api_decode_wire_types.yaml

@@ -0,0 +1,43 @@
+esphome:
+  name: api-decode-wire-types-test
+host:
+api:
+logger:
+  level: DEBUG
+
+switch:
+  - platform: template
+    name: "Wire Switch"
+    optimistic: true
+
+output:
+  - platform: template
+    id: wire_dim
+    type: float
+    write_action:
+      - lambda: ""
+
+light:
+  - platform: monochromatic
+    name: "Wire Light"
+    output: wire_dim
+    default_transition_length: 0s
+    effects:
+      - pulse:
+          name: Pulse
+
+text:
+  - platform: template
+    name: "Wire Text"
+    optimistic: true
+    mode: text
+    min_length: 0
+    max_length: 255
+
+number:
+  - platform: template
+    name: "Wire Number"
+    optimistic: true
+    min_value: -1000
+    max_value: 1000
+    step: 0.5

tests/integration/fixtures/api_empty_message_roundtrip.yaml

@@ -0,0 +1,11 @@
+esphome:
+  name: api-empty-message-test
+host:
+api:
+logger:
+  level: DEBUG
+
+switch:
+  - platform: template
+    name: "Empty Message Switch"
+    optimistic: true

tests/integration/fixtures/api_encode_boundaries.yaml

@@ -0,0 +1,58 @@
+esphome:
+  name: api-encode-boundaries-test
+  # Top-level area fills DeviceInfoResponse.suggested_area (field 16, a two-byte tag)
+  area:
+    id: kitchen_area
+    name: Kitchen
+  on_boot:
+    - sensor.template.publish:
+        id: zero_then_value
+        state: 0.0
+
+host:
+api:
+logger:
+  level: DEBUG
+
+sensor:
+  - platform: template
+    name: "Zero Then Value"
+    id: zero_then_value
+    # Negative int32 takes the ten byte varint path
+    accuracy_decimals: -2
+    update_interval: never
+
+text_sensor:
+  - platform: template
+    name: "Long Text"
+    id: long_text
+    update_interval: never
+
+number:
+  - platform: template
+    name: "Negative Number"
+    optimistic: true
+    min_value: -1000
+    max_value: 1000
+    step: 0.5
+    initial_value: -123.5
+
+select:
+  - platform: template
+    name: "Long Option Select"
+    optimistic: true
+    options:
+      - short
+      - "option-with-a-name-long-enough-that-its-length-prefix-needs-two-varint-bytes-when-the-list-entities-response-is-encoded-xxxxxxxxxx"
+    initial_option: short
+
+button:
+  - platform: template
+    name: "Publish Values"
+    on_press:
+      - sensor.template.publish:
+          id: zero_then_value
+          state: 12.5
+      - text_sensor.template.publish:
+          id: long_text
+          state: !lambda return std::string(200, 'y');

tests/integration/raw_api_client.py

@@ -125,11 +125,12 @@ class RawApiClient:
         await self.read_until_frame(MESSAGE_TYPE_OF[api_pb2.HelloResponse])
 
     async def send_message(self, msg: message.Message) -> None:
+        await self.send_raw(MESSAGE_TYPE_OF[type(msg)], msg.SerializeToString())
+
+    async def send_raw(self, msg_type: int, payload: bytes) -> None:
+        """Send a frame with a hand built payload, for shapes protobuf will not serialize."""
         loop = asyncio.get_running_loop()
-        await loop.sock_sendall(
-            self._sock,
-            encode_frame(MESSAGE_TYPE_OF[type(msg)], msg.SerializeToString()),
-        )
+        await loop.sock_sendall(self._sock, encode_frame(msg_type, payload))
 
     async def read_until_frame(self, msg_type: int, timeout: float = 10.0) -> None:
         """Read until at least one frame of msg_type has been received."""

tests/integration/state_utils.py

@@ -57,6 +57,46 @@ async def wait_for_state(
     return await asyncio.wait_for(future, timeout=timeout)
 
 
+class StateWaiter:
+    """Route one state subscription to any number of predicate waits."""
+
+    def __init__(self) -> None:
+        self._waiters: list[
+            tuple[Callable[[EntityState], bool], asyncio.Future[EntityState]]
+        ] = []
+
+    def on_state(self, state: EntityState) -> None:
+        for predicate, future in self._waiters:
+            if future.done():
+                continue
+            try:
+                matched = predicate(state)
+            except Exception as exc:  # noqa: BLE001  the wait re-raises it, the callback must not die
+                future.set_exception(exc)
+                continue
+            if matched:
+                future.set_result(state)
+
+    async def expect(
+        self,
+        predicate: Callable[[EntityState], bool],
+        timeout: float = 5.0,
+        label: str | None = None,
+    ) -> EntityState:
+        """Wait for the next state matching ``predicate``; states seen before this call do not count."""
+        entry = (predicate, asyncio.get_running_loop().create_future())
+        self._waiters.append(entry)
+        try:
+            async with asyncio.timeout(timeout):
+                return await entry[1]
+        except TimeoutError:
+            raise TimeoutError(
+                f"no state matched {label or predicate} within {timeout}s"
+            ) from None
+        finally:
+            self._waiters.remove(entry)
+
+
 def find_entity[T: EntityInfo](
     entities: list[EntityInfo],
     object_id_substring: str,

tests/integration/test_api_decode_wire_types.py

@@ -0,0 +1,142 @@
+"""decode_field() must take fields that match their declared wire type, drop the ones that do
+not, skip unknown fields, and handle two byte tags, varints and length prefixes."""
+
+from __future__ import annotations
+
+from collections.abc import Callable
+import struct
+
+from aioesphomeapi import (
+    EntityState,
+    LightState,
+    NumberState,
+    SwitchState,
+    TextState,
+    api_pb2,
+)
+import pytest
+
+from .raw_api_client import MESSAGE_TYPE_OF, RawApiClient, encode_varint
+from .state_utils import InitialStateHelper, StateWaiter, require_entity
+from .types import APIClientConnectedFactory, RunCompiledFunction
+
+SWITCH_COMMAND = MESSAGE_TYPE_OF[api_pb2.SwitchCommandRequest]
+WIRE_VARINT, WIRE_LENGTH, WIRE_FIXED32 = 0, 2, 5
+
+
+def tag(field: int, wire_type: int) -> bytes:
+    return encode_varint((field << 3) | wire_type)
+
+
+@pytest.mark.asyncio
+async def test_api_decode_wire_types(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+    unused_tcp_port: int,
+) -> None:
+    async with (
+        run_compiled(yaml_config),
+        api_client_connected() as client,
+        RawApiClient(unused_tcp_port) as raw,
+    ):
+        entities, _ = await client.list_entities_services()
+        switch = require_entity(entities, "wire_switch")
+        light = require_entity(entities, "wire_light")
+        text = require_entity(entities, "wire_text")
+        number = require_entity(entities, "wire_number")
+        key = tag(1, WIRE_FIXED32) + struct.pack("<I", switch.key)
+        on, off = tag(2, WIRE_VARINT) + b"\x01", tag(2, WIRE_VARINT) + b"\x00"
+
+        switch_states: list[bool] = []
+        waiter = StateWaiter()
+
+        def on_state(state: EntityState) -> None:
+            if isinstance(state, SwitchState) and state.key == switch.key:
+                switch_states.append(state.state)
+            waiter.on_state(state)
+
+        def switch_is(value: bool) -> Callable[[EntityState], bool]:
+            return lambda s: (
+                isinstance(s, SwitchState) and s.key == switch.key and s.state is value
+            )
+
+        def number_is(value: float) -> Callable[[EntityState], bool]:
+            return lambda s: (
+                isinstance(s, NumberState) and s.key == number.key and s.state == value
+            )
+
+        initial = InitialStateHelper(entities)
+        client.subscribe_states(initial.on_state_wrapper(on_state))
+        await initial.wait_for_initial_states()
+        await raw.connect()
+
+        # A well formed command: fixed32 key, varint state
+        await raw.send_raw(SWITCH_COMMAND, key + on)
+        await waiter.expect(switch_is(True))
+        await raw.send_raw(SWITCH_COMMAND, key + off)
+        await waiter.expect(switch_is(False))
+
+        # The same field with the wrong wire type is dropped, and a varint key never matches an
+        # entity; each of these would turn the switch on if the payload were read as a varint
+        seen = len(switch_states)
+        await raw.send_raw(SWITCH_COMMAND, key + tag(2, WIRE_LENGTH) + b"\x01\x01")
+        await raw.send_raw(
+            SWITCH_COMMAND, key + tag(2, WIRE_FIXED32) + b"\x01\x00\x00\x00"
+        )
+        await raw.send_raw(
+            SWITCH_COMMAND, tag(1, WIRE_VARINT) + encode_varint(switch.key) + on
+        )
+        # Ordered on the raw socket itself: this frame cannot be parsed before the bad ones, so
+        # the only switch state since the marker must be the one it produces
+        await raw.send_raw(SWITCH_COMMAND, key + on)
+        await waiter.expect(switch_is(True), label="switch on after wrong wire types")
+        assert switch_states[seen:] == [True]
+        await raw.send_raw(SWITCH_COMMAND, key + off)
+        await waiter.expect(switch_is(False))
+
+        # Truncated bodies stop the decode loop without taking the connection down: a tag with its
+        # continuation bit set and nothing after it, a length prefix past the end of the payload,
+        # and a fixed32 with two of its four bytes
+        seen = len(switch_states)
+        await raw.send_raw(SWITCH_COMMAND, key + b"\x80")
+        await raw.send_raw(SWITCH_COMMAND, key + tag(2, WIRE_LENGTH) + b"\x7f" + b"ab")
+        await raw.send_raw(SWITCH_COMMAND, tag(1, WIRE_FIXED32) + b"\x01\x02")
+        await raw.send_raw(SWITCH_COMMAND, key + on)
+        await waiter.expect(switch_is(True), label="switch on after truncated frames")
+        assert switch_states[seen:] == [True]
+        await raw.send_raw(SWITCH_COMMAND, key + off)
+        await waiter.expect(switch_is(False))
+
+        # A negative number goes through the fixed32 float path of a normal client
+        client.number_command(number.key, -77.5)
+        await waiter.expect(number_is(-77.5))
+
+        # An unknown field ahead of the known ones is skipped; field 200 needs a two byte tag
+        await raw.send_raw(
+            SWITCH_COMMAND, tag(200, WIRE_VARINT) + encode_varint(300) + key + on
+        )
+        await waiter.expect(switch_is(True))
+
+        # Two byte tags (effect fields 18 and 19) and a two byte varint (300 ms transition)
+        client.light_command(
+            light.key, state=True, brightness=0.5, transition_length=0.3, effect="Pulse"
+        )
+        await waiter.expect(
+            lambda s: (
+                isinstance(s, LightState) and s.key == light.key and s.effect == "Pulse"
+            )
+        )
+        client.light_command(light.key, effect="None", state=False)
+        await waiter.expect(
+            lambda s: isinstance(s, LightState) and s.key == light.key and not s.state
+        )
+
+        # A string whose length prefix needs two varint bytes
+        long_text = "w" * 200
+        client.text_command(text.key, long_text)
+        await waiter.expect(
+            lambda s: (
+                isinstance(s, TextState) and s.key == text.key and s.state == long_text
+            )
+        )

tests/integration/test_api_empty_message_roundtrip.py

@@ -0,0 +1,37 @@
+"""Messages without fields go through the shared ProtoMessage entry points on both directions."""
+
+from __future__ import annotations
+
+from aioesphomeapi import api_pb2
+import pytest
+
+from .raw_api_client import MESSAGE_TYPE_OF, RawApiClient
+from .types import RunCompiledFunction
+
+
+@pytest.mark.asyncio
+async def test_api_empty_message_roundtrip(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    unused_tcp_port: int,
+) -> None:
+    async with run_compiled(yaml_config), RawApiClient(unused_tcp_port) as client:
+        await client.connect()
+
+        # Field free request and reply on the plain send path
+        await client.send_message(api_pb2.PingRequest())
+        await client.read_until_frame(MESSAGE_TYPE_OF[api_pb2.PingResponse])
+
+        # Field free request answered by a message with fields, and a list that ends with
+        # the field free ListEntitiesDoneResponse through the batching path
+        await client.send_message(api_pb2.DeviceInfoRequest())
+        await client.read_until_frame(MESSAGE_TYPE_OF[api_pb2.DeviceInfoResponse])
+        await client.send_message(api_pb2.ListEntitiesRequest())
+        await client.read_until_frame(MESSAGE_TYPE_OF[api_pb2.ListEntitiesDoneResponse])
+        assert (
+            client.frame_counts[MESSAGE_TYPE_OF[api_pb2.ListEntitiesSwitchResponse]]
+            == 1
+        )
+
+        await client.send_message(api_pb2.DisconnectRequest())
+        await client.read_until_frame(MESSAGE_TYPE_OF[api_pb2.DisconnectResponse])

tests/integration/test_api_encode_boundaries.py

@@ -0,0 +1,78 @@
+"""Encode paths at their branch boundaries: zero skipped float, fixed32 state, negative int32,
+length prefixes of two varint bytes and two byte field tags."""
+
+from __future__ import annotations
+
+import asyncio
+
+from aioesphomeapi import (
+    NumberState,
+    SelectInfo,
+    SensorInfo,
+    SensorState,
+    TextSensorState,
+)
+import pytest
+
+from .state_utils import InitialStateHelper, StateWaiter, require_entity
+from .types import APIClientConnectedFactory, RunCompiledFunction
+
+LONG_OPTION = (
+    "option-with-a-name-long-enough-that-its-length-prefix-needs-two-varint-bytes-"
+    "when-the-list-entities-response-is-encoded-xxxxxxxxxx"
+)
+
+
+@pytest.mark.asyncio
+async def test_api_encode_boundaries(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+) -> None:
+    async with run_compiled(yaml_config), api_client_connected() as client:
+        device_info, (entities, _) = await asyncio.gather(
+            client.device_info(), client.list_entities_services()
+        )
+        assert device_info.suggested_area == "Kitchen"
+
+        sensor = require_entity(entities, "zero_then_value", SensorInfo)
+        assert sensor.accuracy_decimals == -2
+        select = require_entity(entities, "long_option_select", SelectInfo)
+        assert len(LONG_OPTION) >= 128
+        assert select.options == ["short", LONG_OPTION]
+        text = require_entity(entities, "long_text")
+        number = require_entity(entities, "negative_number")
+        button = require_entity(entities, "publish_values")
+
+        initial = InitialStateHelper(entities)
+        waiter = StateWaiter()
+        client.subscribe_states(initial.on_state_wrapper(waiter.on_state))
+        await initial.wait_for_initial_states()
+
+        # A float of exactly zero is skipped on the wire and must still read as 0.0, not missing
+        first = initial.initial_states[sensor.key]
+        assert isinstance(first, SensorState)
+        assert first.state == 0.0 and not first.missing_state
+        first_number = initial.initial_states[number.key]
+        assert isinstance(first_number, NumberState)
+        assert first_number.state == -123.5
+
+        client.button_command(button.key)
+        await asyncio.gather(
+            waiter.expect(
+                lambda s: (
+                    isinstance(s, SensorState)
+                    and s.key == sensor.key
+                    and s.state == 12.5
+                ),
+                label="sensor 12.5",
+            ),
+            waiter.expect(
+                lambda s: (
+                    isinstance(s, TextSensorState)
+                    and s.key == text.key
+                    and s.state == "y" * 200
+                ),
+                label="text 200 x y",
+            ),
+        )

tests/unit_tests/components/api/test_api_proto.py

@@ -194,17 +194,17 @@ def test_superseded_device_info_fields_still_declared_in_header() -> None:
 
 def test_superseded_device_info_fields_still_encoded_and_sized() -> None:
     """Each superseded field must still be touched by DeviceInfoResponse's
-    generated encode() and calculate_size(), i.e. it is still put on the wire.
+    generated encode_msg() and calc_size_msg(), i.e. it is still put on the wire.
     """
-    encode_body = _extract_function_body(CPP_TEXT, "DeviceInfoResponse::encode")
-    size_body = _extract_function_body(CPP_TEXT, "DeviceInfoResponse::calculate_size")
+    encode_body = _extract_function_body(CPP_TEXT, "DeviceInfoResponse::encode_msg")
+    size_body = _extract_function_body(CPP_TEXT, "DeviceInfoResponse::calc_size_msg")
     for field_name in SUPERSEDED_FIELDS:
-        assert f"this->{field_name}" in encode_body, (
-            f"DeviceInfoResponse::encode() no longer references {field_name}. "
+        assert f"msg.{field_name}" in encode_body, (
+            f"DeviceInfoResponse::encode_msg() no longer references {field_name}. "
             f"{DEPRECATED_FIELD_TRAP}"
         )
-        assert f"this->{field_name}" in size_body, (
-            f"DeviceInfoResponse::calculate_size() no longer references "
+        assert f"msg.{field_name}" in size_body, (
+            f"DeviceInfoResponse::calc_size_msg() no longer references "
             f"{field_name}. {DEPRECATED_FIELD_TRAP}"
         )
 
@@ -380,3 +380,13 @@ def test_api_version_minor_is_at_least_15() -> None:
         "clients to see api_version >= 1.15 in HelloResponse before they will "
         "ever request it."
     )
+
+
+def test_generated_encode_calls_keep_the_cursor() -> None:
+    """No generated ProtoEncode call may drop the returned cursor."""
+    dropped = [
+        line
+        for line in CPP_TEXT.splitlines()
+        if "ProtoEncode::" in line and "pos = ProtoEncode::" not in line
+    ]
+    assert not dropped, dropped[:5]

tests/unit_tests/components/api/test_api_protobuf_generator.py

@@ -15,9 +15,13 @@ import pytest
 
 sys.path.insert(0, str(Path(__file__).parents[4] / "script" / "api_protobuf"))
 
+import aioesphomeapi.api_options_pb2 as pb  # noqa: E402
 from api_protobuf import (  # noqa: E402
     MAX_MESSAGE_ID,
+    SOURCE_CLIENT,
     _make_ifdef_line,
+    build_message_type,
+    create_field_type_info,
     get_varint64_ifdef,
     validate_message_id,
 )
@@ -34,16 +38,26 @@ def _file_with_messages(
     file_desc = descriptor_pb2.FileDescriptorProto(name="test.proto")
     for name, field_type, deprecated in messages:
         msg = file_desc.message_type.add(name=name)
-        field = msg.field.add(name="value", number=1, type=field_type)
+        field = msg.field.add()
+        field.CopyFrom(_field(field_type))
         field.options.deprecated = deprecated
     return file_desc
 
 
 UINT64 = descriptor_pb2.FieldDescriptorProto.TYPE_UINT64
+MESSAGE = descriptor_pb2.FieldDescriptorProto.TYPE_MESSAGE
+DOUBLE = descriptor_pb2.FieldDescriptorProto.TYPE_DOUBLE
 INT64 = descriptor_pb2.FieldDescriptorProto.TYPE_INT64
 SINT64 = descriptor_pb2.FieldDescriptorProto.TYPE_SINT64
 UINT32 = descriptor_pb2.FieldDescriptorProto.TYPE_UINT32
+INT32 = descriptor_pb2.FieldDescriptorProto.TYPE_INT32
+SINT32 = descriptor_pb2.FieldDescriptorProto.TYPE_SINT32
 FIXED64 = descriptor_pb2.FieldDescriptorProto.TYPE_FIXED64
+FIXED32 = descriptor_pb2.FieldDescriptorProto.TYPE_FIXED32
+FLOAT = descriptor_pb2.FieldDescriptorProto.TYPE_FLOAT
+BOOL = descriptor_pb2.FieldDescriptorProto.TYPE_BOOL
+STRING = descriptor_pb2.FieldDescriptorProto.TYPE_STRING
+BYTES = descriptor_pb2.FieldDescriptorProto.TYPE_BYTES
 
 
 def test_no_varint64_fields() -> None:
@@ -107,3 +121,222 @@ def test_message_id_at_maximum_is_accepted() -> None:
 def test_message_id_above_maximum_is_rejected() -> None:
     with pytest.raises(ValueError, match="exceeds the plaintext"):
         validate_message_id(MAX_MESSAGE_ID + 1, "TooBigMessage")
+
+
+def _field(
+    field_type: int, number: int = 1, *, force: bool = False, repeated: bool = False
+) -> descriptor_pb2.FieldDescriptorProto:
+    field = descriptor_pb2.FieldDescriptorProto(
+        name="value", number=number, type=field_type
+    )
+    if repeated:
+        field.label = descriptor_pb2.FieldDescriptorProto.LABEL_REPEATED
+    if force:
+        field.options.Extensions[pb.force] = True
+    return field
+
+
+def _encode_field(
+    field_type: int, number: int = 1, force: bool = False, repeated: bool = False
+) -> str:
+    """Return the encode statement the generator emits for one encode-only field."""
+    field = _field(field_type, number, force=force, repeated=repeated)
+    return create_field_type_info(
+        field, needs_decode=False, needs_encode=True
+    ).encode_content
+
+
+SCALAR_TYPES = [
+    BOOL,
+    UINT32,
+    INT32,
+    UINT64,
+    INT64,
+    SINT32,
+    FLOAT,
+    FIXED32,
+    STRING,
+    BYTES,
+]
+
+
+@pytest.mark.parametrize("field_type", SCALAR_TYPES)
+def test_forced_fields_use_the_force_overload_or_raw_writes(field_type: int) -> None:
+    content = _encode_field(field_type, force=True)
+    assert (
+        "_force(" in content
+        or "write_raw_byte(" in content
+        or "write_tag_and_fixed32(" in content
+    ), content
+
+
+@pytest.mark.parametrize("field_type", [FLOAT, FIXED32])
+def test_single_byte_tag_fixed32_shares_the_outlined_writer(field_type: int) -> None:
+    unconditional = _encode_field(field_type, force=True)
+    assert unconditional.count("write_tag_and_fixed32(pos, 13,") == 1, unconditional
+    guarded = _encode_field(field_type, force=False)
+    assert guarded.startswith("if ("), guarded
+    assert "[[likely]]" in guarded
+    assert "write_tag_and_fixed32(pos, 13," in guarded
+
+
+@pytest.mark.parametrize("field_type", [FLOAT, FIXED32])
+def test_multi_byte_tag_fixed32_falls_back_to_the_generic_helper(
+    field_type: int,
+) -> None:
+    content = _encode_field(field_type, number=16)
+    assert "write_tag_and_fixed32" not in content, content
+    assert content.startswith("pos = ProtoEncode::encode_"), content
+
+
+def _decode_case(field_type: int, number: int, *, repeated: bool = False) -> str:
+    """Return the decode_field() case the generator emits for one decoded field."""
+    field = _field(field_type, number, repeated=repeated)
+    if field_type == MESSAGE:
+        field.type_name = ".Sub"
+    return create_field_type_info(
+        field, needs_decode=True, needs_encode=False
+    ).decode_content
+
+
+@pytest.mark.parametrize(
+    ("needs_decode", "force", "member"),
+    [
+        (False, False, "StringRef value{nullptr, 0};  // null until set, encode only"),
+        (True, False, "StringRef value{};"),
+        (False, True, "StringRef value{};"),
+    ],
+)
+def test_string_fields_default_to_null_only_when_never_read(
+    needs_decode: bool, force: bool, member: str
+) -> None:
+    """Only a string that is neither decoded nor force encoded may start as a null StringRef."""
+    ti = create_field_type_info(
+        _field(STRING, force=force), needs_decode=needs_decode, needs_encode=True
+    )
+    assert ti.public_content == [member]
+
+
+@pytest.mark.parametrize(
+    ("field_type", "number", "wire_type", "accessor"),
+    [
+        (UINT32, 2, "WIRE_TYPE_VARINT", "value.as_varint()"),
+        (BOOL, 3, "WIRE_TYPE_VARINT", "value.as_bool()"),
+        (STRING, 1, "WIRE_TYPE_LENGTH_DELIMITED", "value.data()"),
+        (FLOAT, 4, "WIRE_TYPE_FIXED32", "value.as_float()"),
+        (FIXED32, 5, "WIRE_TYPE_FIXED32", "value.as_fixed32()"),
+    ],
+)
+def test_decode_cases_carry_field_number_and_wire_type(
+    field_type: int, number: int, wire_type: str, accessor: str
+) -> None:
+    """Each decoded field yields one case keyed on its number and declared wire type."""
+    case = _decode_case(field_type, number)
+    lines = case.splitlines()
+    assert lines[0] == f"case proto_tag({number}, {wire_type}):", case
+    assert accessor in lines[1], case
+    assert lines[-1].strip() == "break;", case
+
+
+@pytest.mark.parametrize(
+    ("field_type", "repeated", "wire_type", "store"),
+    [
+        (UINT32, True, "WIRE_TYPE_VARINT", "this->value.push_back(value.as_varint());"),
+        (
+            STRING,
+            True,
+            "WIRE_TYPE_LENGTH_DELIMITED",
+            "this->value.push_back(value.as_string());",
+        ),
+        (
+            MESSAGE,
+            False,
+            "WIRE_TYPE_LENGTH_DELIMITED",
+            "value.decode_to_message(this->value);",
+        ),
+        (
+            MESSAGE,
+            True,
+            "WIRE_TYPE_LENGTH_DELIMITED",
+            "value.decode_to_message(this->value.back());",
+        ),
+    ],
+)
+def test_repeated_and_message_fields_decode_through_the_same_case_shape(
+    field_type: int, repeated: bool, wire_type: str, store: str
+) -> None:
+    """Repeated and sub message fields land in the one switch with their own store."""
+    case = _decode_case(field_type, 7, repeated=repeated)
+    lines = case.splitlines()
+    assert lines[0] == f"case proto_tag(7, {wire_type}):", case
+    assert store in case, case
+    if field_type == MESSAGE and repeated:
+        assert "this->value.emplace_back();" in case, case
+    assert lines[-1].strip() == "break;", case
+
+
+def test_a_fixed64_field_fails_at_generation_time() -> None:
+    """The decode loop has no 64 bit wire type path, so such a field must never reach it silently."""
+    desc = descriptor_pb2.DescriptorProto(name="Wide")
+    desc.field.add(name="ratio", number=1, type=DOUBLE)
+    with pytest.raises(
+        ValueError, match="64-bit type 'double' .*ratio.* not supported"
+    ):
+        build_message_type(desc, {}, {"Wide": SOURCE_CLIENT})
+
+
+def test_message_decodes_through_one_static_decode_field() -> None:
+    """All wire types of a decoded message land in one static decode_field() switch that the
+    inline decode() hands to the shared loop."""
+    desc = descriptor_pb2.DescriptorProto(name="Mixed")
+    desc.field.add(name="name", number=1, type=STRING)
+    desc.field.add(name="count", number=2, type=UINT32)
+    desc.field.add(name="level", number=3, type=FLOAT)
+    header, cpp, _ = build_message_type(desc, {}, {"Mixed": SOURCE_CLIENT})
+    decl = "static void decode_field(void *self, uint32_t tag, const uint8_t *data, proto_varint_value_t scalar);"
+    assert header.count(decl) == 1
+    assert (
+        cpp.count(
+            "void Mixed::decode_field(void *self, uint32_t tag, const uint8_t *data, proto_varint_value_t scalar) {"
+        )
+        == 1
+    )
+    assert "switch (tag) {" in cpp
+    assert "const ProtoFieldValue value(data, scalar);" in cpp
+    for number, wire_type in (
+        (1, "WIRE_TYPE_LENGTH_DELIMITED"),
+        (2, "WIRE_TYPE_VARINT"),
+        (3, "WIRE_TYPE_FIXED32"),
+    ):
+        assert f"case proto_tag({number}, {wire_type}):" in cpp, cpp
+    # The static body works on the cast message, never on this
+    assert "auto &msg = *static_cast<Mixed *>(self);" in cpp
+    assert "this->" not in cpp
+    assert (
+        header.count(
+            "ProtoDecodableMessage::decode_fields(this, buffer, length, &decode_field);"
+        )
+        == 1
+    )
+
+
+def test_fixed_vector_message_keeps_its_own_decode() -> None:
+    """A message that sizes a FixedVector first decodes through its own decode(), not the inline one."""
+    desc = descriptor_pb2.DescriptorProto(name="Sized")
+    field = desc.field.add(name="values", number=1, type=UINT32)
+    field.label = descriptor_pb2.FieldDescriptorProto.LABEL_REPEATED
+    field.options.Extensions[pb.fixed_vector] = True
+    header, cpp, _ = build_message_type(desc, {}, {"Sized": SOURCE_CLIENT})
+    assert (
+        "ProtoDecodableMessage::decode_fields(this, buffer, length, &decode_field);"
+        not in header
+    )
+    assert header.count("void decode(const uint8_t *buffer, size_t length);") == 1
+    assert "void Sized::decode(const uint8_t *buffer, size_t length) {" in cpp
+    assert "ProtoDecodableMessage::count_repeated_field(buffer, length, 1)" in cpp
+    assert (
+        cpp.count(
+            "ProtoDecodableMessage::decode_fields(this, buffer, length, &decode_field);"
+        )
+        == 1
+    )