Prevent ping id allocation conflict with device_tracker (#48969)

* Prevent ping id allocation conflict with device_tracker

- Solves id conflict resulting unexpected home state

* Update homeassistant/components/ping/device_tracker.py

Co-authored-by: Paulus Schoutsen <paulus@home-assistant.io>

homeassistant/components/ping/__init__.py

@@ -24,20 +24,22 @@ async def async_setup(hass, config):
 
 
 @callback
-def async_get_next_ping_id(hass):
+def async_get_next_ping_id(hass, count=1):
     """Find the next id to use in the outbound ping.
 
+    When using multiping, we increment the id
+    by the number of ids that multiping
+    will use.
+
     Must be called in async
     """
-    current_id = hass.data[DOMAIN][PING_ID]
+    allocated_id = hass.data[DOMAIN][PING_ID] + 1
-    if current_id == MAX_PING_ID:
+    if allocated_id > MAX_PING_ID:
-        next_id = DEFAULT_START_ID
+        allocated_id -= MAX_PING_ID - DEFAULT_START_ID
-    else:
+    hass.data[DOMAIN][PING_ID] += count
-        next_id = current_id + 1
+    if hass.data[DOMAIN][PING_ID] > MAX_PING_ID:
-
+        hass.data[DOMAIN][PING_ID] -= MAX_PING_ID - DEFAULT_START_ID
-    hass.data[DOMAIN][PING_ID] = next_id
+    return allocated_id
-
-    return next_id
 
 
 def _can_use_icmp_lib_with_privilege() -> None | bool:

homeassistant/components/ping/device_tracker.py

@@ -125,7 +125,7 @@ async def async_setup_scanner(hass, config, async_see, discovery_info=None):
                     count=PING_ATTEMPTS_COUNT,
                     timeout=ICMP_TIMEOUT,
                     privileged=privileged,
-                    id=async_get_next_ping_id(hass),
+                    id=async_get_next_ping_id(hass, len(ip_to_dev_id)),
                 )
             )
             _LOGGER.debug("Multiping responses: %s", responses)

tests/components/ping/test_init.py

@@ -0,0 +1,27 @@
+"""Test ping id allocation."""
+
+from homeassistant.components.ping import async_get_next_ping_id
+from homeassistant.components.ping.const import (
+    DEFAULT_START_ID,
+    DOMAIN,
+    MAX_PING_ID,
+    PING_ID,
+)
+
+
+async def test_async_get_next_ping_id(hass):
+    """Verify we allocate ping ids as expected."""
+    hass.data[DOMAIN] = {PING_ID: DEFAULT_START_ID}
+
+    assert async_get_next_ping_id(hass) == DEFAULT_START_ID + 1
+    assert async_get_next_ping_id(hass) == DEFAULT_START_ID + 2
+    assert async_get_next_ping_id(hass, 2) == DEFAULT_START_ID + 3
+    assert async_get_next_ping_id(hass) == DEFAULT_START_ID + 5
+
+    hass.data[DOMAIN][PING_ID] = MAX_PING_ID
+    assert async_get_next_ping_id(hass) == DEFAULT_START_ID + 1
+    assert async_get_next_ping_id(hass) == DEFAULT_START_ID + 2
+
+    hass.data[DOMAIN][PING_ID] = MAX_PING_ID
+    assert async_get_next_ping_id(hass, 2) == DEFAULT_START_ID + 1
+    assert async_get_next_ping_id(hass) == DEFAULT_START_ID + 3