[binary_sensor] Fix reporting of 'unknown' (#12296)

Co-authored-by: Jonathan Swoboda <154711427+swoboda1337@users.noreply.github.com>
Co-authored-by: J. Nick Koston <nick@home-assistant.io>

esphome/components/binary_sensor/binary_sensor.cpp

@@ -34,13 +34,20 @@ void BinarySensor::publish_initial_state(bool new_state) {
 void BinarySensor::send_state_internal(bool new_state) {
   // copy the new state to the visible property for backwards compatibility, before any callbacks
   this->state = new_state;
-  // Note that set_state_ de-dups and will only trigger callbacks if the state has actually changed
+  // Note that set_new_state_ de-dups and will only trigger callbacks if the state has actually changed
-  if (this->set_state_(new_state)) {
+  this->set_new_state(new_state);
-    ESP_LOGD(TAG, "'%s': New state is %s", this->get_name().c_str(), ONOFF(new_state));
+}
+
+bool BinarySensor::set_new_state(const optional<bool> &new_state) {
+  if (StatefulEntityBase::set_new_state(new_state)) {
+    // weirdly, this file could be compiled even without USE_BINARY_SENSOR defined
 #if defined(USE_BINARY_SENSOR) && defined(USE_CONTROLLER_REGISTRY)
     ControllerRegistry::notify_binary_sensor_update(this);
 #endif
+    ESP_LOGD(TAG, "'%s': %s", this->get_name().c_str(), ONOFFMAYBE(new_state));
+    return true;
   }
+  return false;
 }
 
 void BinarySensor::add_filter(Filter *filter) {

esphome/components/binary_sensor/binary_sensor.h

@@ -61,6 +61,8 @@ class BinarySensor : public StatefulEntityBase<bool>, public EntityBase_DeviceCl
 
  protected:
   Filter *filter_list_{nullptr};
+
+  bool set_new_state(const optional<bool> &new_state) override;
 };
 
 class BinarySensorInitiallyOff : public BinarySensor {

esphome/core/entity_base.h

@@ -205,7 +205,7 @@ template<typename T> class StatefulEntityBase : public EntityBase {
   virtual bool has_state() const { return this->state_.has_value(); }
   virtual const T &get_state() const { return this->state_.value(); }
   virtual T get_state_default(T default_value) const { return this->state_.value_or(default_value); }
-  void invalidate_state() { this->set_state_({}); }
+  void invalidate_state() { this->set_new_state({}); }
 
   void add_full_state_callback(std::function<void(optional<T> previous, optional<T> current)> &&callback) {
     if (this->full_state_callbacks_ == nullptr)
@@ -227,20 +227,20 @@ template<typename T> class StatefulEntityBase : public EntityBase {
   /**
    * Set a new state for this entity. This will trigger callbacks only if the new state is different from the previous.
    *
-   * @param state The new state.
+   * @param new_state The new state.
    * @return True if the state was changed, false if it was the same as before.
    */
-  bool set_state_(const optional<T> &state) {
+  virtual bool set_new_state(const optional<T> &new_state) {
-    if (this->state_ != state) {
+    if (this->state_ != new_state) {
       // call the full state callbacks with the previous and new state
       if (this->full_state_callbacks_ != nullptr)
-        this->full_state_callbacks_->call(this->state_, state);
+        this->full_state_callbacks_->call(this->state_, new_state);
       // trigger legacy callbacks only if the new state is valid and either the trigger on initial state is enabled or
       // the previous state was valid
       auto had_state = this->has_state();
-      this->state_ = state;
+      this->state_ = new_state;
-      if (this->state_callbacks_ != nullptr && state.has_value() && (this->trigger_on_initial_state_ || had_state))
+      if (this->state_callbacks_ != nullptr && new_state.has_value() && (this->trigger_on_initial_state_ || had_state))
-        this->state_callbacks_->call(state.value());
+        this->state_callbacks_->call(new_state.value());
       return true;
     }
     return false;

tests/integration/README.md

@@ -7,7 +7,7 @@ This directory contains end-to-end integration tests for ESPHome, focusing on te
 - `conftest.py` - Common fixtures and utilities
 - `const.py` - Constants used throughout the integration tests
 - `types.py` - Type definitions for fixtures and functions
-- `state_utils.py` - State handling utilities (e.g., `InitialStateHelper`, `build_key_to_entity_mapping`)
+- `state_utils.py` - State handling utilities (e.g., `InitialStateHelper`, `find_entity`, `require_entity`)
 - `fixtures/` - YAML configuration files for tests
 - `test_*.py` - Individual test files
 
@@ -53,6 +53,28 @@ The `InitialStateHelper` class solves a common problem in integration tests: whe
 **Future work:**
 Consider converting existing integration tests to use `InitialStateHelper` for more reliable state tracking and to eliminate race conditions related to initial state broadcasts.
 
+#### Entity Lookup Helpers (`state_utils.py`)
+
+Two helper functions simplify finding entities in test code:
+
+**`find_entity(entities, object_id_substring, entity_type=None)`**
+- Finds an entity by searching for a substring in its `object_id` (case-insensitive)
+- Optionally filters by entity type (e.g., `BinarySensorInfo`)
+- Returns `None` if not found
+
+**`require_entity(entities, object_id_substring, entity_type=None, description=None)`**
+- Same as `find_entity` but raises `AssertionError` if not found
+- Use `description` parameter for clearer error messages
+
+```python
+from aioesphomeapi import BinarySensorInfo
+from .state_utils import require_entity
+
+# Find entities with clear error messages
+binary_sensor = require_entity(entities, "test_sensor", BinarySensorInfo)
+button = require_entity(entities, "set_true", description="Set True button")
+```
+
 ### Writing Tests
 
 The simplest way to write a test is to use the `run_compiled` and `api_client_connected` fixtures:

tests/integration/fixtures/binary_sensor_invalidate_state.yaml

@@ -0,0 +1,39 @@
+esphome:
+  name: test-binary-sensor-invalidate
+
+host:
+api:
+  batch_delay: 0ms  # Disable batching to receive all state updates
+logger:
+  level: DEBUG
+
+# Template binary sensor that we can control
+binary_sensor:
+  - platform: template
+    name: "Test Binary Sensor"
+    id: test_binary_sensor
+
+# Buttons to control the binary sensor state
+button:
+  - platform: template
+    name: "Set True"
+    id: set_true_button
+    on_press:
+      - binary_sensor.template.publish:
+          id: test_binary_sensor
+          state: true
+
+  - platform: template
+    name: "Set False"
+    id: set_false_button
+    on_press:
+      - binary_sensor.template.publish:
+          id: test_binary_sensor
+          state: false
+
+  - platform: template
+    name: "Invalidate State"
+    id: invalidate_button
+    on_press:
+      - binary_sensor.invalidate_state:
+          id: test_binary_sensor

tests/integration/state_utils.py

@@ -4,11 +4,74 @@ from __future__ import annotations
 
 import asyncio
 import logging
+from typing import TypeVar
 
 from aioesphomeapi import ButtonInfo, EntityInfo, EntityState
 
 _LOGGER = logging.getLogger(__name__)
 
+T = TypeVar("T", bound=EntityInfo)
+
+
+def find_entity(
+    entities: list[EntityInfo],
+    object_id_substring: str,
+    entity_type: type[T] | None = None,
+) -> T | EntityInfo | None:
+    """Find an entity by object_id substring and optionally by type.
+
+    Args:
+        entities: List of entity info objects from the API
+        object_id_substring: Substring to search for in object_id (case-insensitive)
+        entity_type: Optional entity type to filter by (e.g., BinarySensorInfo)
+
+    Returns:
+        The first matching entity, or None if not found
+
+    Example:
+        binary_sensor = find_entity(entities, "test_binary_sensor", BinarySensorInfo)
+        button = find_entity(entities, "set_true")  # Any entity type
+    """
+    substring_lower = object_id_substring.lower()
+    for entity in entities:
+        if substring_lower in entity.object_id.lower() and (
+            entity_type is None or isinstance(entity, entity_type)
+        ):
+            return entity
+    return None
+
+
+def require_entity(
+    entities: list[EntityInfo],
+    object_id_substring: str,
+    entity_type: type[T] | None = None,
+    description: str | None = None,
+) -> T | EntityInfo:
+    """Find an entity or raise AssertionError if not found.
+
+    Args:
+        entities: List of entity info objects from the API
+        object_id_substring: Substring to search for in object_id (case-insensitive)
+        entity_type: Optional entity type to filter by (e.g., BinarySensorInfo)
+        description: Human-readable description for error message
+
+    Returns:
+        The first matching entity
+
+    Raises:
+        AssertionError: If no matching entity is found
+
+    Example:
+        binary_sensor = require_entity(entities, "test_sensor", BinarySensorInfo)
+        button = require_entity(entities, "set_true", description="Set True button")
+    """
+    entity = find_entity(entities, object_id_substring, entity_type)
+    if entity is None:
+        desc = description or f"entity with '{object_id_substring}' in object_id"
+        type_info = f" of type {entity_type.__name__}" if entity_type else ""
+        raise AssertionError(f"{desc}{type_info} not found in entities")
+    return entity
+
 
 def build_key_to_entity_mapping(
     entities: list[EntityInfo], entity_names: list[str]

tests/integration/test_binary_sensor_invalidate_state.py

@@ -0,0 +1,138 @@
+"""Integration test for binary_sensor.invalidate_state() functionality.
+
+This tests the fix in PR #12296 where invalidate_state() was not properly
+reporting the 'unknown' state to the API. The binary sensor should report
+missing_state=True when invalidated.
+
+Regression test for: https://github.com/esphome/esphome/issues/12252
+"""
+
+from __future__ import annotations
+
+import asyncio
+
+from aioesphomeapi import BinarySensorInfo, BinarySensorState, EntityState
+import pytest
+
+from .state_utils import InitialStateHelper, require_entity
+from .types import APIClientConnectedFactory, RunCompiledFunction
+
+
+@pytest.mark.asyncio
+async def test_binary_sensor_invalidate_state(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+) -> None:
+    """Test that binary_sensor.invalidate_state() reports unknown to the API.
+
+    This verifies that:
+    1. Binary sensor starts with missing_state=True (no initial state)
+    2. Publishing true sets missing_state=False and state=True
+    3. Publishing false sets missing_state=False and state=False
+    4. Invalidating state sets missing_state=True (unknown state)
+    """
+    loop = asyncio.get_running_loop()
+
+    # Track state changes
+    states_received: list[BinarySensorState] = []
+    state_future: asyncio.Future[BinarySensorState] = loop.create_future()
+
+    def on_state(state: EntityState) -> None:
+        """Track binary sensor state changes."""
+        if isinstance(state, BinarySensorState):
+            states_received.append(state)
+            if not state_future.done():
+                state_future.set_result(state)
+
+    async with (
+        run_compiled(yaml_config),
+        api_client_connected() as client,
+    ):
+        # Verify device info
+        device_info = await client.device_info()
+        assert device_info is not None
+        assert device_info.name == "test-binary-sensor-invalidate"
+
+        # Get entities
+        entities, _ = await client.list_entities_services()
+
+        # Find our binary sensor and buttons using helper
+        binary_sensor = require_entity(entities, "test_binary_sensor", BinarySensorInfo)
+        set_true_button = require_entity(
+            entities, "set_true", description="Set True button"
+        )
+        set_false_button = require_entity(
+            entities, "set_false", description="Set False button"
+        )
+        invalidate_button = require_entity(
+            entities, "invalidate", description="Invalidate button"
+        )
+
+        # Set up initial state helper to handle the initial state broadcast
+        initial_state_helper = InitialStateHelper(entities)
+        client.subscribe_states(initial_state_helper.on_state_wrapper(on_state))
+
+        # Wait for initial states
+        try:
+            await initial_state_helper.wait_for_initial_states()
+        except TimeoutError:
+            pytest.fail("Timeout waiting for initial states")
+
+        # Check initial state - should be missing (unknown)
+        initial_state = initial_state_helper.initial_states.get(binary_sensor.key)
+        assert initial_state is not None, "No initial state received for binary sensor"
+        assert isinstance(initial_state, BinarySensorState)
+        assert initial_state.missing_state is True, (
+            f"Initial state should have missing_state=True, got {initial_state}"
+        )
+
+        # Test 1: Set state to true
+        states_received.clear()
+        state_future = loop.create_future()
+        client.button_command(set_true_button.key)
+
+        try:
+            state = await asyncio.wait_for(state_future, timeout=5.0)
+        except TimeoutError:
+            pytest.fail("Timeout waiting for state=true")
+
+        assert state.missing_state is False, (
+            f"After setting true, missing_state should be False, got {state}"
+        )
+        assert state.state is True, f"Expected state=True, got {state}"
+
+        # Test 2: Set state to false
+        states_received.clear()
+        state_future = loop.create_future()
+        client.button_command(set_false_button.key)
+
+        try:
+            state = await asyncio.wait_for(state_future, timeout=5.0)
+        except TimeoutError:
+            pytest.fail("Timeout waiting for state=false")
+
+        assert state.missing_state is False, (
+            f"After setting false, missing_state should be False, got {state}"
+        )
+        assert state.state is False, f"Expected state=False, got {state}"
+
+        # Test 3: Invalidate state (set to unknown)
+        # This is the critical test for the bug fix
+        states_received.clear()
+        state_future = loop.create_future()
+        client.button_command(invalidate_button.key)
+
+        try:
+            state = await asyncio.wait_for(state_future, timeout=5.0)
+        except TimeoutError:
+            pytest.fail(
+                "Timeout waiting for invalidated state - "
+                "binary_sensor.invalidate_state() may not be reporting to the API. "
+                "See issue #12252."
+            )
+
+        assert state.missing_state is True, (
+            f"After invalidate_state(), missing_state should be True (unknown), "
+            f"got {state}. This is the regression from issue #12252."
+        )