[esp32_ble_tracker] Fix missed BLE advertisements with WiFi on ESP-IDF 5.5.5 (#18356)

tests/component_tests/ble_device_base/test_scan_parameter_validation.py

@@ -57,7 +57,12 @@ def test_bk72xx_defaults_are_valid() -> None:
 
 
 def test_esp32_defaults_are_valid() -> None:
-    """esp32 pins the ESP-IDF reference rate and exposes active (default on)."""
+    """esp32 pins the ESP-IDF reference rate and exposes active (default on).
+
+    Without wifi loaded, the conditional window default falls back to the
+    historical 30 ms; the wifi-aware resolution is covered by the
+    esp32_ble_tracker component tests.
+    """
     config = ESP32_SCHEMA({})
     assert to_ble_units(config["interval"]) == 512
     assert to_ble_units(config["window"]) == 48

tests/component_tests/esp32_ble_tracker/test_scan_window_default.py

@@ -0,0 +1,122 @@
+"""Tests for the esp32_ble_tracker conditional scan window default.
+
+The scan window default depends on wifi coexistence and the IDF version:
+IDF 5.5.5 fixed a coexistence bug where BLE scans ran far longer than the
+configured window (espressif/esp-idf#18931), so on fixed versions the
+historical 30 ms default would only listen 9.4 % of the time and miss most
+advertisements. With the coexistence arbiter compiled in on a fixed IDF, the
+window instead defaults to the interval, as Espressif recommends; without the
+arbiter a full-duty scan would starve wifi, so the 30 ms default is kept.
+"""
+
+from __future__ import annotations
+
+from collections.abc import Callable
+
+import pytest
+
+from esphome import config_validation as cv
+from esphome.components.ble_device_base import to_ble_units
+from esphome.components.const import CONF_SCAN_PARAMETERS, CONF_WINDOW
+from esphome.components.esp32 import KEY_IDF_VERSION
+from esphome.components.esp32_ble_tracker import (
+    CONF_SOFTWARE_COEXISTENCE,
+    CONFIG_SCHEMA,
+)
+from esphome.const import CONF_INTERVAL, PlatformFramework
+from esphome.core import CORE
+from esphome.types import ConfigType
+
+from ..types import SetCoreConfigCallable
+
+
+@pytest.fixture
+def stage_esp32(
+    set_core_config: SetCoreConfigCallable,
+) -> Callable[..., None]:
+    """Stage an esp32 build with a given IDF version and wifi presence."""
+
+    def stage(idf: str, *, wifi: bool) -> None:
+        set_core_config(
+            PlatformFramework.ESP32_IDF,
+            platform_data={KEY_IDF_VERSION: cv.Version.parse(idf)},
+        )
+        if wifi:
+            # Makes cv.OnlyWith default software_coexistence to True, exactly
+            # as a real config with wifi: does.
+            CORE.loaded_integrations.add("wifi")
+
+    return stage
+
+
+def _scan_params(config: ConfigType) -> ConfigType:
+    return CONFIG_SCHEMA(config)[CONF_SCAN_PARAMETERS]
+
+
+@pytest.mark.parametrize(
+    ("idf", "config", "expected_units"),
+    [
+        ("5.5.5", {}, 512),  # first fixed version, default 320 ms interval
+        ("6.0.1", {}, 512),  # any newer version behaves the same
+        # Follows a user-set interval.
+        ("5.5.5", {"scan_parameters": {"interval": "1s"}}, 1600),
+    ],
+)
+def test_wifi_on_fixed_idf_defaults_window_to_interval(
+    stage_esp32: Callable[..., None],
+    idf: str,
+    config: ConfigType,
+    expected_units: int,
+) -> None:
+    """With wifi coexistence on a fixed IDF, the window defaults to the interval."""
+    stage_esp32(idf, wifi=True)
+    params = _scan_params(config)
+    assert params[CONF_WINDOW] == params[CONF_INTERVAL]
+    assert to_ble_units(params[CONF_WINDOW]) == expected_units
+
+
+@pytest.mark.parametrize(
+    ("idf", "wifi", "config"),
+    [
+        # Buggy IDF over-scans anyway; keep the 30 ms default.
+        ("5.5.4", True, {}),
+        # No wifi (e.g. ethernet) means no radio contention.
+        ("5.5.5", False, {}),
+        # Coexistence disabled: no arbiter, so a full-duty scan would starve
+        # wifi outright.
+        ("5.5.5", True, {CONF_SOFTWARE_COEXISTENCE: False}),
+    ],
+)
+def test_30ms_default_kept(
+    stage_esp32: Callable[..., None],
+    idf: str,
+    wifi: bool,
+    config: ConfigType,
+) -> None:
+    stage_esp32(idf, wifi=wifi)
+    assert to_ble_units(_scan_params(config)[CONF_WINDOW]) == 48
+
+
+@pytest.mark.parametrize("window", ["60ms", "30ms"])
+def test_explicit_window_is_never_touched(
+    stage_esp32: Callable[..., None], window: str
+) -> None:
+    """A user-set window wins over the conditional default.
+
+    The explicit 30 ms case matters: it is indistinguishable from the
+    defaulted value by inspection, so the defaulted flag must separate them.
+    """
+    stage_esp32("5.5.5", wifi=True)
+    params = _scan_params({"scan_parameters": {"window": window}})
+    assert to_ble_units(params[CONF_WINDOW]) == to_ble_units(
+        cv.positive_time_period(window)
+    )
+
+
+def test_short_interval_without_window_still_rejected(
+    stage_esp32: Callable[..., None],
+) -> None:
+    """The provisional 30 ms default validates against the interval as before."""
+    stage_esp32("5.5.5", wifi=True)
+    with pytest.raises(cv.Invalid, match="needs to be smaller than scan interval"):
+        _scan_params({"scan_parameters": {"interval": "20ms"}})