Merge branch 'dev' into dashboard_import_url_store_rodata

2025.11.0b3

esphome/components/cover/automation.h

@@ -4,8 +4,7 @@
 #include "esphome/core/automation.h"
 #include "cover.h"
 
-namespace esphome {
-namespace cover {
+namespace esphome::cover {
 
 template<typename... Ts> class OpenAction : public Action<Ts...> {
  public:
@@ -131,5 +130,4 @@ class CoverClosedTrigger : public Trigger<> {
   }
 };
 
-}  // namespace cover
-}  // namespace esphome
+}  // namespace esphome::cover

esphome/components/cover/cover.cpp

@@ -6,8 +6,7 @@
 
 #include "esphome/core/log.h"
 
-namespace esphome {
-namespace cover {
+namespace esphome::cover {
 
 static const char *const TAG = "cover";
 
@@ -212,5 +211,4 @@ void CoverRestoreState::apply(Cover *cover) {
   cover->publish_state();
 }
 
-}  // namespace cover
-}  // namespace esphome
+}  // namespace esphome::cover

esphome/components/cover/cover.h

@@ -7,8 +7,7 @@
 
 #include "cover_traits.h"
 
-namespace esphome {
-namespace cover {
+namespace esphome::cover {
 
 const extern float COVER_OPEN;
 const extern float COVER_CLOSED;
@@ -157,5 +156,4 @@ class Cover : public EntityBase, public EntityBase_DeviceClass {
   ESPPreferenceObject rtc_;
 };
 
-}  // namespace cover
-}  // namespace esphome
+}  // namespace esphome::cover

esphome/components/cover/cover_traits.h

@@ -1,7 +1,6 @@
 #pragma once
 
-namespace esphome {
-namespace cover {
+namespace esphome::cover {
 
 class CoverTraits {
  public:
@@ -26,5 +25,4 @@ class CoverTraits {
   bool supports_stop_{false};
 };
 
-}  // namespace cover
-}  // namespace esphome
+}  // namespace esphome::cover

esphome/components/dashboard_import/dashboard_import.cpp

@@ -3,10 +3,10 @@
 namespace esphome {
 namespace dashboard_import {
 
-static std::string g_package_import_url;  // NOLINT
+static const char *g_package_import_url = "";  // NOLINT
 
-const std::string &get_package_import_url() { return g_package_import_url; }
-void set_package_import_url(std::string url) { g_package_import_url = std::move(url); }
+const char *get_package_import_url() { return g_package_import_url; }
+void set_package_import_url(const char *url) { g_package_import_url = url; }
 
 }  // namespace dashboard_import
 }  // namespace esphome

esphome/components/dashboard_import/dashboard_import.h

@@ -1,12 +1,10 @@
 #pragma once
 
-#include <string>
-
 namespace esphome {
 namespace dashboard_import {
 
-const std::string &get_package_import_url();
-void set_package_import_url(std::string url);
+const char *get_package_import_url();
+void set_package_import_url(const char *url);
 
 }  // namespace dashboard_import
 }  // namespace esphome

esphome/components/mdns/mdns_component.cpp

@@ -135,8 +135,7 @@ void MDNSComponent::compile_records_(StaticVector<MDNSService, MDNS_SERVICE_COUN
 
 #ifdef USE_DASHBOARD_IMPORT
     MDNS_STATIC_CONST_CHAR(TXT_PACKAGE_IMPORT_URL, "package_import_url");
-    txt_records.push_back(
-        {MDNS_STR(TXT_PACKAGE_IMPORT_URL), MDNS_STR(dashboard_import::get_package_import_url().c_str())});
+    txt_records.push_back({MDNS_STR(TXT_PACKAGE_IMPORT_URL), MDNS_STR(dashboard_import::get_package_import_url())});
 #endif
   }
 #endif  // USE_API

esphome/components/sntp/time.py

@@ -1,9 +1,14 @@
+import logging
+
 import esphome.codegen as cg
 from esphome.components import time as time_
+from esphome.config_helpers import merge_config
 import esphome.config_validation as cv
 from esphome.const import (
     CONF_ID,
+    CONF_PLATFORM,
     CONF_SERVERS,
+    CONF_TIME,
     PLATFORM_BK72XX,
     PLATFORM_ESP32,
     PLATFORM_ESP8266,
@@ -12,13 +17,74 @@ from esphome.const import (
     PLATFORM_RTL87XX,
 )
 from esphome.core import CORE
+import esphome.final_validate as fv
+from esphome.types import ConfigType
+
+_LOGGER = logging.getLogger(__name__)
 
 DEPENDENCIES = ["network"]
+
+CONF_SNTP = "sntp"
+
 sntp_ns = cg.esphome_ns.namespace("sntp")
 SNTPComponent = sntp_ns.class_("SNTPComponent", time_.RealTimeClock)
 
 DEFAULT_SERVERS = ["0.pool.ntp.org", "1.pool.ntp.org", "2.pool.ntp.org"]
 
+
+def _sntp_final_validate(config: ConfigType) -> None:
+    """Merge multiple SNTP instances into one, similar to OTA merging behavior."""
+    full_conf = fv.full_config.get()
+    time_confs = full_conf.get(CONF_TIME, [])
+
+    sntp_configs: list[ConfigType] = []
+    other_time_configs: list[ConfigType] = []
+
+    for time_conf in time_confs:
+        if time_conf.get(CONF_PLATFORM) == CONF_SNTP:
+            sntp_configs.append(time_conf)
+        else:
+            other_time_configs.append(time_conf)
+
+    if len(sntp_configs) <= 1:
+        return
+
+    # Merge all SNTP configs into the first one
+    merged = sntp_configs[0]
+    for sntp_conf in sntp_configs[1:]:
+        # Validate that IDs are consistent if manually specified
+        if merged[CONF_ID].is_manual and sntp_conf[CONF_ID].is_manual:
+            raise cv.Invalid(
+                f"Found multiple SNTP configurations but {CONF_ID} is inconsistent"
+            )
+        merged = merge_config(merged, sntp_conf)
+
+    # Deduplicate servers while preserving order
+    servers = merged[CONF_SERVERS]
+    unique_servers = list(dict.fromkeys(servers))
+
+    # Warn if we're dropping servers due to 3-server limit
+    if len(unique_servers) > 3:
+        dropped = unique_servers[3:]
+        unique_servers = unique_servers[:3]
+        _LOGGER.warning(
+            "SNTP supports maximum 3 servers. Dropped excess server(s): %s",
+            dropped,
+        )
+
+    merged[CONF_SERVERS] = unique_servers
+
+    _LOGGER.warning(
+        "Found and merged %d SNTP time configurations into one instance",
+        len(sntp_configs),
+    )
+
+    # Replace time configs with merged SNTP + other time platforms
+    other_time_configs.append(merged)
+    full_conf[CONF_TIME] = other_time_configs
+    fv.full_config.set(full_conf)
+
+
 CONFIG_SCHEMA = cv.All(
     time_.TIME_SCHEMA.extend(
         {
@@ -40,6 +106,8 @@ CONFIG_SCHEMA = cv.All(
     ),
 )
 
+FINAL_VALIDATE_SCHEMA = _sntp_final_validate
+
 
 async def to_code(config):
     servers = config[CONF_SERVERS]

esphome/components/uart/uart_component_esp8266.cpp

@@ -56,11 +56,19 @@ uint32_t ESP8266UartComponent::get_config() {
 }
 
 void ESP8266UartComponent::setup() {
-  if (this->rx_pin_) {
-    this->rx_pin_->setup();
-  }
-  if (this->tx_pin_ && this->rx_pin_ != this->tx_pin_) {
-    this->tx_pin_->setup();
+  auto setup_pin_if_needed = [](InternalGPIOPin *pin) {
+    if (!pin) {
+      return;
+    }
+    const auto mask = gpio::Flags::FLAG_OPEN_DRAIN | gpio::Flags::FLAG_PULLUP | gpio::Flags::FLAG_PULLDOWN;
+    if ((pin->get_flags() & mask) != gpio::Flags::FLAG_NONE) {
+      pin->setup();
+    }
+  };
+
+  setup_pin_if_needed(this->rx_pin_);
+  if (this->rx_pin_ != this->tx_pin_) {
+    setup_pin_if_needed(this->tx_pin_);
   }
 
   // Use Arduino HardwareSerial UARTs if all used pins match the ones

esphome/components/uart/uart_component_esp_idf.cpp

@@ -133,11 +133,19 @@ void IDFUARTComponent::load_settings(bool dump_config) {
     return;
   }
 
-  if (this->rx_pin_) {
-    this->rx_pin_->setup();
-  }
-  if (this->tx_pin_ && this->rx_pin_ != this->tx_pin_) {
-    this->tx_pin_->setup();
+  auto setup_pin_if_needed = [](InternalGPIOPin *pin) {
+    if (!pin) {
+      return;
+    }
+    const auto mask = gpio::Flags::FLAG_OPEN_DRAIN | gpio::Flags::FLAG_PULLUP | gpio::Flags::FLAG_PULLDOWN;
+    if ((pin->get_flags() & mask) != gpio::Flags::FLAG_NONE) {
+      pin->setup();
+    }
+  };
+
+  setup_pin_if_needed(this->rx_pin_);
+  if (this->rx_pin_ != this->tx_pin_) {
+    setup_pin_if_needed(this->tx_pin_);
   }
 
   int8_t tx = this->tx_pin_ != nullptr ? this->tx_pin_->get_pin() : -1;

esphome/components/uart/uart_component_libretiny.cpp

@@ -53,7 +53,7 @@ void LibreTinyUARTComponent::setup() {
 
   auto shouldFallbackToSoftwareSerial = [&]() -> bool {
     auto hasFlags = [](InternalGPIOPin *pin, const gpio::Flags mask) -> bool {
-      return pin && pin->get_flags() & mask != gpio::Flags::FLAG_NONE;
+      return pin && (pin->get_flags() & mask) != gpio::Flags::FLAG_NONE;
     };
     if (hasFlags(this->tx_pin_, gpio::Flags::FLAG_OPEN_DRAIN | gpio::Flags::FLAG_PULLUP | gpio::Flags::FLAG_PULLDOWN) ||
         hasFlags(this->rx_pin_, gpio::Flags::FLAG_OPEN_DRAIN | gpio::Flags::FLAG_PULLUP | gpio::Flags::FLAG_PULLDOWN)) {

esphome/components/uart/uart_component_rp2040.cpp

@@ -52,11 +52,19 @@ uint16_t RP2040UartComponent::get_config() {
 }
 
 void RP2040UartComponent::setup() {
-  if (this->rx_pin_) {
-    this->rx_pin_->setup();
-  }
-  if (this->tx_pin_ && this->rx_pin_ != this->tx_pin_) {
-    this->tx_pin_->setup();
+  auto setup_pin_if_needed = [](InternalGPIOPin *pin) {
+    if (!pin) {
+      return;
+    }
+    const auto mask = gpio::Flags::FLAG_OPEN_DRAIN | gpio::Flags::FLAG_PULLUP | gpio::Flags::FLAG_PULLDOWN;
+    if ((pin->get_flags() & mask) != gpio::Flags::FLAG_NONE) {
+      pin->setup();
+    }
+  };
+
+  setup_pin_if_needed(this->rx_pin_);
+  if (this->rx_pin_ != this->tx_pin_) {
+    setup_pin_if_needed(this->tx_pin_);
   }
 
   uint16_t config = get_config();

esphome/components/web_server/ota/__init__.py

@@ -1,10 +1,17 @@
+import logging
+
 import esphome.codegen as cg
 from esphome.components.esp32 import add_idf_component
 from esphome.components.ota import BASE_OTA_SCHEMA, OTAComponent, ota_to_code
+from esphome.config_helpers import merge_config
 import esphome.config_validation as cv
-from esphome.const import CONF_ID
+from esphome.const import CONF_ID, CONF_OTA, CONF_PLATFORM, CONF_WEB_SERVER
 from esphome.core import CORE, coroutine_with_priority
 from esphome.coroutine import CoroPriority
+import esphome.final_validate as fv
+from esphome.types import ConfigType
+
+_LOGGER = logging.getLogger(__name__)
 
 CODEOWNERS = ["@esphome/core"]
 DEPENDENCIES = ["network", "web_server_base"]
@@ -12,6 +19,53 @@ DEPENDENCIES = ["network", "web_server_base"]
 web_server_ns = cg.esphome_ns.namespace("web_server")
 WebServerOTAComponent = web_server_ns.class_("WebServerOTAComponent", OTAComponent)
 
+
+def _web_server_ota_final_validate(config: ConfigType) -> None:
+    """Merge multiple web_server OTA instances into one.
+
+    Multiple web_server OTA instances register duplicate HTTP handlers for /update,
+    causing undefined behavior. Merge them into a single instance.
+    """
+    full_conf = fv.full_config.get()
+    ota_confs = full_conf.get(CONF_OTA, [])
+
+    web_server_ota_configs: list[ConfigType] = []
+    other_ota_configs: list[ConfigType] = []
+
+    for ota_conf in ota_confs:
+        if ota_conf.get(CONF_PLATFORM) == CONF_WEB_SERVER:
+            web_server_ota_configs.append(ota_conf)
+        else:
+            other_ota_configs.append(ota_conf)
+
+    if len(web_server_ota_configs) <= 1:
+        return
+
+    # Merge all web_server OTA configs into the first one
+    merged = web_server_ota_configs[0]
+    for ota_conf in web_server_ota_configs[1:]:
+        # Validate that IDs are consistent if manually specified
+        if (
+            merged[CONF_ID].is_manual
+            and ota_conf[CONF_ID].is_manual
+            and merged[CONF_ID] != ota_conf[CONF_ID]
+        ):
+            raise cv.Invalid(
+                f"Found multiple web_server OTA configurations but {CONF_ID} is inconsistent"
+            )
+        merged = merge_config(merged, ota_conf)
+
+    _LOGGER.warning(
+        "Found and merged %d web_server OTA configurations into one instance",
+        len(web_server_ota_configs),
+    )
+
+    # Replace OTA configs with merged web_server + other OTA platforms
+    other_ota_configs.append(merged)
+    full_conf[CONF_OTA] = other_ota_configs
+    fv.full_config.set(full_conf)
+
+
 CONFIG_SCHEMA = (
     cv.Schema(
         {
@@ -22,6 +76,8 @@ CONFIG_SCHEMA = (
     .extend(cv.COMPONENT_SCHEMA)
 )
 
+FINAL_VALIDATE_SCHEMA = _web_server_ota_final_validate
+
 
 @coroutine_with_priority(CoroPriority.WEB_SERVER_OTA)
 async def to_code(config):

esphome/components/web_server_idf/web_server_idf.cpp

@@ -489,10 +489,18 @@ AsyncEventSourceResponse::AsyncEventSourceResponse(const AsyncWebServerRequest *
 
 void AsyncEventSourceResponse::destroy(void *ptr) {
   auto *rsp = static_cast<AsyncEventSourceResponse *>(ptr);
-  ESP_LOGD(TAG, "Event source connection closed (fd: %d)", rsp->fd_.load());
-  // Mark as dead by setting fd to 0 - will be cleaned up in the main loop
-  rsp->fd_.store(0);
-  // Note: We don't delete or remove from set here to avoid race conditions
+  int fd = rsp->fd_.exchange(0);  // Atomically get and clear fd
+
+  if (fd > 0) {
+    ESP_LOGD(TAG, "Event source connection closed (fd: %d)", fd);
+    // Immediately shut down the socket to prevent lwIP from delivering more data
+    // This prevents "recv_tcp: recv for wrong pcb!" assertions when the TCP stack
+    // tries to deliver queued data after the session is marked as dead
+    // See: https://github.com/esphome/esphome/issues/11936
+    shutdown(fd, SHUT_RDWR);
+    // Note: We don't close() the socket - httpd owns it and will close it
+  }
+  // Session will be cleaned up in the main loop to avoid race conditions
 }
 
 // helper for allowing only unique entries in the queue

esphome/config.py

@@ -338,21 +338,44 @@ def check_replaceme(value):
         )
 
 
-def _build_list_index(lst):
+def _get_item_id(item: Any) -> str | Extend | Remove | None:
+    """Attempts to get a list item's ID"""
+    if not isinstance(item, dict):
+        return None  # not a dict, can't have ID
+    # 1.- Check regular case:
+    # - id: my_id
+    item_id = item.get(CONF_ID)
+    if item_id is None and len(item) == 1:
+        # 2.- Check single-key dict case:
+        # - obj:
+        #     id: my_id
+        item = next(iter(item.values()))
+        if isinstance(item, dict):
+            item_id = item.get(CONF_ID)
+    if isinstance(item_id, Extend):
+        # Remove instances of Extend so they don't overwrite the original item when merging:
+        del item[CONF_ID]
+    return item_id
+
+
+def _build_list_index(
+    lst: list[Any],
+) -> tuple[
+    OrderedDict[str | Extend | Remove, Any], list[tuple[int, str, Any]], set[str]
+]:
     index = OrderedDict()
     extensions, removals = [], set()
-    for item in lst:
+    for pos, item in enumerate(lst):
         if item is None:
             removals.add(None)
             continue
-        item_id = None
-        if isinstance(item, dict) and (item_id := item.get(CONF_ID)):
-            if isinstance(item_id, Extend):
-                extensions.append(item)
-                continue
-            if isinstance(item_id, Remove):
-                removals.add(item_id.value)
-                continue
+        item_id = _get_item_id(item)
+        if isinstance(item_id, Extend):
+            extensions.append((pos, item_id.value, item))
+            continue
+        if isinstance(item_id, Remove):
+            removals.add(item_id.value)
+            continue
         if not item_id or item_id in index:
             # no id or duplicate -> pass through with identity-based key
             item_id = id(item)
@@ -360,7 +383,7 @@ def _build_list_index(lst):
     return index, extensions, removals
 
 
-def resolve_extend_remove(value, is_key=None):
+def resolve_extend_remove(value: Any, is_key: bool = False) -> None:
     if isinstance(value, ESPLiteralValue):
         return  # do not check inside literal blocks
     if isinstance(value, list):
@@ -368,26 +391,16 @@ def resolve_extend_remove(value, is_key=None):
         if extensions or removals:
             # Rebuild the original list after
             # processing all extensions and removals
-            for item in extensions:
-                item_id = item[CONF_ID].value
+            for pos, item_id, item in extensions:
                 if item_id in removals:
                     continue
                 old = index.get(item_id)
                 if old is None:
                     # Failed to find source for extension
-                    # Find index of item to show error at correct position
-                    i = next(
-                        (
-                            i
-                            for i, d in enumerate(value)
-                            if d.get(CONF_ID) == item[CONF_ID]
-                        )
-                    )
-                    with cv.prepend_path(i):
+                    with cv.prepend_path(pos):
                         raise cv.Invalid(
                             f"Source for extension of ID '{item_id}' was not found."
                         )
-                item[CONF_ID] = item_id
                 index[item_id] = merge_config(old, item)
             for item_id in removals:
                 index.pop(item_id, None)

tests/component_tests/ota/test_web_server_ota.py

@@ -1,6 +1,18 @@
 """Tests for the web_server OTA platform."""
 
+from __future__ import annotations
+
 from collections.abc import Callable
+import logging
+from typing import Any
+
+import pytest
+
+from esphome import config_validation as cv
+from esphome.components.web_server.ota import _web_server_ota_final_validate
+from esphome.const import CONF_ID, CONF_OTA, CONF_PLATFORM, CONF_WEB_SERVER
+from esphome.core import ID
+import esphome.final_validate as fv
 
 
 def test_web_server_ota_generated(generate_main: Callable[[str], str]) -> None:
@@ -100,3 +112,144 @@ def test_web_server_ota_esp8266(generate_main: Callable[[str], str]) -> None:
     # Check web server OTA component is present
     assert "WebServerOTAComponent" in main_cpp
     assert "web_server::WebServerOTAComponent" in main_cpp
+
+
+@pytest.mark.parametrize(
+    ("ota_configs", "expected_count", "warning_expected"),
+    [
+        pytest.param(
+            [
+                {
+                    CONF_PLATFORM: CONF_WEB_SERVER,
+                    CONF_ID: ID("ota_web", is_manual=False),
+                }
+            ],
+            1,
+            False,
+            id="single_instance_no_merge",
+        ),
+        pytest.param(
+            [
+                {
+                    CONF_PLATFORM: CONF_WEB_SERVER,
+                    CONF_ID: ID("ota_web_1", is_manual=False),
+                },
+                {
+                    CONF_PLATFORM: CONF_WEB_SERVER,
+                    CONF_ID: ID("ota_web_2", is_manual=False),
+                },
+            ],
+            1,
+            True,
+            id="two_instances_merged",
+        ),
+        pytest.param(
+            [
+                {
+                    CONF_PLATFORM: CONF_WEB_SERVER,
+                    CONF_ID: ID("ota_web_1", is_manual=False),
+                },
+                {
+                    CONF_PLATFORM: "esphome",
+                    CONF_ID: ID("ota_esphome", is_manual=False),
+                },
+                {
+                    CONF_PLATFORM: CONF_WEB_SERVER,
+                    CONF_ID: ID("ota_web_2", is_manual=False),
+                },
+            ],
+            2,
+            True,
+            id="mixed_platforms_web_server_merged",
+        ),
+    ],
+)
+def test_web_server_ota_instance_merging(
+    ota_configs: list[dict[str, Any]],
+    expected_count: int,
+    warning_expected: bool,
+    caplog: pytest.LogCaptureFixture,
+) -> None:
+    """Test web_server OTA instance merging behavior."""
+    full_conf = {CONF_OTA: ota_configs.copy()}
+
+    token = fv.full_config.set(full_conf)
+    try:
+        with caplog.at_level(logging.WARNING):
+            _web_server_ota_final_validate({})
+
+        updated_conf = fv.full_config.get()
+
+        # Verify total number of OTA platforms
+        assert len(updated_conf[CONF_OTA]) == expected_count
+
+        # Verify warning
+        if warning_expected:
+            assert any(
+                "Found and merged" in record.message
+                and "web_server OTA" in record.message
+                for record in caplog.records
+            ), "Expected merge warning not found in log"
+        else:
+            assert len(caplog.records) == 0, "Unexpected warnings logged"
+    finally:
+        fv.full_config.reset(token)
+
+
+def test_web_server_ota_consistent_manual_ids(
+    caplog: pytest.LogCaptureFixture,
+) -> None:
+    """Test that consistent manual IDs can be merged successfully."""
+    ota_configs = [
+        {
+            CONF_PLATFORM: CONF_WEB_SERVER,
+            CONF_ID: ID("ota_web", is_manual=True),
+        },
+        {
+            CONF_PLATFORM: CONF_WEB_SERVER,
+            CONF_ID: ID("ota_web", is_manual=True),
+        },
+    ]
+
+    full_conf = {CONF_OTA: ota_configs}
+
+    token = fv.full_config.set(full_conf)
+    try:
+        with caplog.at_level(logging.WARNING):
+            _web_server_ota_final_validate({})
+
+        updated_conf = fv.full_config.get()
+        assert len(updated_conf[CONF_OTA]) == 1
+        assert updated_conf[CONF_OTA][0][CONF_ID].id == "ota_web"
+        assert any(
+            "Found and merged" in record.message and "web_server OTA" in record.message
+            for record in caplog.records
+        )
+    finally:
+        fv.full_config.reset(token)
+
+
+def test_web_server_ota_inconsistent_manual_ids() -> None:
+    """Test that inconsistent manual IDs raise an error."""
+    ota_configs = [
+        {
+            CONF_PLATFORM: CONF_WEB_SERVER,
+            CONF_ID: ID("ota_web_1", is_manual=True),
+        },
+        {
+            CONF_PLATFORM: CONF_WEB_SERVER,
+            CONF_ID: ID("ota_web_2", is_manual=True),
+        },
+    ]
+
+    full_conf = {CONF_OTA: ota_configs}
+
+    token = fv.full_config.set(full_conf)
+    try:
+        with pytest.raises(
+            cv.Invalid,
+            match="Found multiple web_server OTA configurations but id is inconsistent",
+        ):
+            _web_server_ota_final_validate({})
+    finally:
+        fv.full_config.reset(token)

tests/component_tests/sntp/__init__.py

@@ -0,0 +1 @@
+"""Tests for SNTP component."""

tests/component_tests/sntp/config/sntp_test.yaml

@@ -0,0 +1,22 @@
+esphome:
+  name: sntp-test
+
+esp32:
+  board: esp32dev
+  framework:
+    type: esp-idf
+
+wifi:
+  ssid: "testssid"
+  password: "testpassword"
+
+# Test multiple SNTP instances that should be merged
+time:
+  - platform: sntp
+    servers:
+      - 192.168.1.1
+      - pool.ntp.org
+  - platform: sntp
+    servers:
+      - pool.ntp.org
+      - 192.168.1.2

tests/component_tests/sntp/test_init.py

@@ -0,0 +1,238 @@
+"""Tests for SNTP time configuration validation."""
+
+from __future__ import annotations
+
+import logging
+from typing import Any
+
+import pytest
+
+from esphome import config_validation as cv
+from esphome.components.sntp.time import CONF_SNTP, _sntp_final_validate
+from esphome.const import CONF_ID, CONF_PLATFORM, CONF_SERVERS, CONF_TIME
+from esphome.core import ID
+import esphome.final_validate as fv
+
+
+@pytest.mark.parametrize(
+    ("time_configs", "expected_count", "expected_servers", "warning_messages"),
+    [
+        pytest.param(
+            [
+                {
+                    CONF_PLATFORM: CONF_SNTP,
+                    CONF_ID: ID("sntp_time", is_manual=False),
+                    CONF_SERVERS: ["192.168.1.1", "pool.ntp.org"],
+                }
+            ],
+            1,
+            ["192.168.1.1", "pool.ntp.org"],
+            [],
+            id="single_instance_no_merge",
+        ),
+        pytest.param(
+            [
+                {
+                    CONF_PLATFORM: CONF_SNTP,
+                    CONF_ID: ID("sntp_time_1", is_manual=False),
+                    CONF_SERVERS: ["192.168.1.1", "pool.ntp.org"],
+                },
+                {
+                    CONF_PLATFORM: CONF_SNTP,
+                    CONF_ID: ID("sntp_time_2", is_manual=False),
+                    CONF_SERVERS: ["192.168.1.2"],
+                },
+            ],
+            1,
+            ["192.168.1.1", "pool.ntp.org", "192.168.1.2"],
+            ["Found and merged 2 SNTP time configurations into one instance"],
+            id="two_instances_merged",
+        ),
+        pytest.param(
+            [
+                {
+                    CONF_PLATFORM: CONF_SNTP,
+                    CONF_ID: ID("sntp_time_1", is_manual=False),
+                    CONF_SERVERS: ["192.168.1.1", "pool.ntp.org"],
+                },
+                {
+                    CONF_PLATFORM: CONF_SNTP,
+                    CONF_ID: ID("sntp_time_2", is_manual=False),
+                    CONF_SERVERS: ["pool.ntp.org", "192.168.1.2"],
+                },
+            ],
+            1,
+            ["192.168.1.1", "pool.ntp.org", "192.168.1.2"],
+            ["Found and merged 2 SNTP time configurations into one instance"],
+            id="deduplication_preserves_order",
+        ),
+        pytest.param(
+            [
+                {
+                    CONF_PLATFORM: CONF_SNTP,
+                    CONF_ID: ID("sntp_time_1", is_manual=False),
+                    CONF_SERVERS: ["192.168.1.1", "pool.ntp.org"],
+                },
+                {
+                    CONF_PLATFORM: CONF_SNTP,
+                    CONF_ID: ID("sntp_time_2", is_manual=False),
+                    CONF_SERVERS: ["192.168.1.2", "pool2.ntp.org"],
+                },
+                {
+                    CONF_PLATFORM: CONF_SNTP,
+                    CONF_ID: ID("sntp_time_3", is_manual=False),
+                    CONF_SERVERS: ["pool3.ntp.org"],
+                },
+            ],
+            1,
+            ["192.168.1.1", "pool.ntp.org", "192.168.1.2"],
+            [
+                "SNTP supports maximum 3 servers. Dropped excess server(s): ['pool2.ntp.org', 'pool3.ntp.org']",
+                "Found and merged 3 SNTP time configurations into one instance",
+            ],
+            id="three_instances_drops_excess_servers",
+        ),
+        pytest.param(
+            [
+                {
+                    CONF_PLATFORM: CONF_SNTP,
+                    CONF_ID: ID("sntp_time_1", is_manual=False),
+                    CONF_SERVERS: [
+                        "192.168.1.1",
+                        "pool.ntp.org",
+                        "pool.ntp.org",
+                        "192.168.1.1",
+                    ],
+                },
+                {
+                    CONF_PLATFORM: CONF_SNTP,
+                    CONF_ID: ID("sntp_time_2", is_manual=False),
+                    CONF_SERVERS: ["pool.ntp.org", "192.168.1.2"],
+                },
+            ],
+            1,
+            ["192.168.1.1", "pool.ntp.org", "192.168.1.2"],
+            ["Found and merged 2 SNTP time configurations into one instance"],
+            id="deduplication_multiple_duplicates",
+        ),
+    ],
+)
+def test_sntp_instance_merging(
+    time_configs: list[dict[str, Any]],
+    expected_count: int,
+    expected_servers: list[str],
+    warning_messages: list[str],
+    caplog: pytest.LogCaptureFixture,
+) -> None:
+    """Test SNTP instance merging behavior."""
+    # Create a mock full config with time configs
+    full_conf = {CONF_TIME: time_configs.copy()}
+
+    # Set the context var
+    token = fv.full_config.set(full_conf)
+    try:
+        with caplog.at_level(logging.WARNING):
+            _sntp_final_validate({})
+
+        # Get the updated config
+        updated_conf = fv.full_config.get()
+
+        # Check if merging occurred
+        if len(time_configs) > 1:
+            # Verify only one SNTP instance remains
+            sntp_instances = [
+                tc
+                for tc in updated_conf[CONF_TIME]
+                if tc.get(CONF_PLATFORM) == CONF_SNTP
+            ]
+            assert len(sntp_instances) == expected_count
+
+            # Verify server list
+            assert sntp_instances[0][CONF_SERVERS] == expected_servers
+
+            # Verify warnings
+            for expected_msg in warning_messages:
+                assert any(
+                    expected_msg in record.message for record in caplog.records
+                ), f"Expected warning message '{expected_msg}' not found in log"
+        else:
+            # Single instance should not trigger merging or warnings
+            assert len(caplog.records) == 0
+            # Config should be unchanged
+            assert updated_conf[CONF_TIME] == time_configs
+    finally:
+        fv.full_config.reset(token)
+
+
+def test_sntp_inconsistent_manual_ids() -> None:
+    """Test that inconsistent manual IDs raise an error."""
+    # Create configs with manual IDs that are inconsistent
+    time_configs = [
+        {
+            CONF_PLATFORM: CONF_SNTP,
+            CONF_ID: ID("sntp_time_1", is_manual=True),
+            CONF_SERVERS: ["192.168.1.1"],
+        },
+        {
+            CONF_PLATFORM: CONF_SNTP,
+            CONF_ID: ID("sntp_time_2", is_manual=True),
+            CONF_SERVERS: ["192.168.1.2"],
+        },
+    ]
+
+    full_conf = {CONF_TIME: time_configs}
+
+    token = fv.full_config.set(full_conf)
+    try:
+        with pytest.raises(
+            cv.Invalid,
+            match="Found multiple SNTP configurations but id is inconsistent",
+        ):
+            _sntp_final_validate({})
+    finally:
+        fv.full_config.reset(token)
+
+
+def test_sntp_with_other_time_platforms(caplog: pytest.LogCaptureFixture) -> None:
+    """Test that SNTP merging doesn't affect other time platforms."""
+    time_configs = [
+        {
+            CONF_PLATFORM: CONF_SNTP,
+            CONF_ID: ID("sntp_time_1", is_manual=False),
+            CONF_SERVERS: ["192.168.1.1"],
+        },
+        {
+            CONF_PLATFORM: "homeassistant",
+            CONF_ID: ID("homeassistant_time", is_manual=False),
+        },
+        {
+            CONF_PLATFORM: CONF_SNTP,
+            CONF_ID: ID("sntp_time_2", is_manual=False),
+            CONF_SERVERS: ["192.168.1.2"],
+        },
+    ]
+
+    full_conf = {CONF_TIME: time_configs.copy()}
+
+    token = fv.full_config.set(full_conf)
+    try:
+        with caplog.at_level(logging.WARNING):
+            _sntp_final_validate({})
+
+        updated_conf = fv.full_config.get()
+
+        # Should have 2 time platforms: 1 merged SNTP + 1 homeassistant
+        assert len(updated_conf[CONF_TIME]) == 2
+
+        # Find the platforms
+        platforms = {tc[CONF_PLATFORM] for tc in updated_conf[CONF_TIME]}
+        assert platforms == {CONF_SNTP, "homeassistant"}
+
+        # Verify SNTP was merged
+        sntp_instances = [
+            tc for tc in updated_conf[CONF_TIME] if tc[CONF_PLATFORM] == CONF_SNTP
+        ]
+        assert len(sntp_instances) == 1
+        assert sntp_instances[0][CONF_SERVERS] == ["192.168.1.1", "192.168.1.2"]
+    finally:
+        fv.full_config.reset(token)

tests/unit_tests/fixtures/substitutions/05-extend-remove.approved.yaml

@@ -7,3 +7,27 @@ some_component:
     value: 2
   - id: component2
     value: 5
+lvgl:
+  pages:
+    - id: page1
+      widgets:
+        - obj:
+            id: object1
+            x: 3
+            y: 2
+            width: 4
+        - obj:
+            id: object3
+            x: 6
+            y: 12
+            widgets:
+              - obj:
+                  id: object4
+                  x: 14
+                  y: 9
+                  width: 15
+            height: 13
+        - obj:
+            id: object5
+            x: 10
+            y: 11

tests/unit_tests/fixtures/substitutions/05-extend-remove.input.yaml

@@ -13,6 +13,30 @@ packages:
         value: 5
       - id: component3
         value: 6
+  - lvgl:
+      pages:
+        - id: page1
+          widgets:
+            - obj:
+                id: object1
+                x: 1
+                y: 2
+            - obj:
+                id: object2
+                x: 5
+            - obj:
+                id: object3
+                x: 6
+                y: 7
+                widgets:
+                  - obj:
+                      id: object4
+                      x: 8
+                      y: 9
+            - obj:
+                id: object5
+                x: 10
+                y: 11
 
 some_component:
   - id: !extend ${A}
@@ -20,3 +44,23 @@ some_component:
   - id: component2
     value: 3
   - id: !remove ${C}
+
+lvgl:
+  pages:
+    - id: !extend page1
+      widgets:
+        - obj:
+            id: !extend object1
+            x: 3
+            width: 4
+        - obj:
+            id: !remove object2
+        - obj:
+            id: !extend object3
+            y: 12
+            height: 13
+            widgets:
+              - obj:
+                  id: !extend object4
+                  x: 14
+                  width: 15