Add config_entries.async_wait_component (#76980)

Co-authored-by: thecode <levyshay1@gmail.com>

homeassistant/setup.py

@@ -29,11 +29,27 @@ ATTR_COMPONENT = "component"
 
 BASE_PLATFORMS = {platform.value for platform in Platform}
 
+# DATA_SETUP is a dict[str, asyncio.Task[bool]], indicating domains which are currently
+# being setup or which failed to setup
+# - Tasks are added to DATA_SETUP by `async_setup_component`, the key is the domain being setup
+#   and the Task is the `_async_setup_component` helper.
+# - Tasks are removed from DATA_SETUP if setup was successful, that is, the task returned True
+DATA_SETUP = "setup_tasks"
+
+# DATA_SETUP_DONE is a dict [str, asyncio.Event], indicating components which will be setup
+# - Events are added to DATA_SETUP_DONE during bootstrap by async_set_domains_to_be_loaded,
+#   the key is the domain which will be loaded
+# - Events are set and removed from DATA_SETUP_DONE when async_setup_component is finished,
+#   regardless of if the setup was successful or not.
 DATA_SETUP_DONE = "setup_done"
+
+# DATA_SETUP_DONE is a dict [str, datetime], indicating when an attempt to setup a component
+# started
 DATA_SETUP_STARTED = "setup_started"
+
+# DATA_SETUP_TIME is a dict [str, timedelta], indicating how time was spent setting up a component
 DATA_SETUP_TIME = "setup_time"
 
-DATA_SETUP = "setup_tasks"
 DATA_DEPS_REQS = "deps_reqs_processed"
 
 SLOW_SETUP_WARNING = 10
@@ -44,7 +60,9 @@ SLOW_SETUP_MAX_WAIT = 300
 def async_set_domains_to_be_loaded(hass: core.HomeAssistant, domains: set[str]) -> None:
     """Set domains that are going to be loaded from the config.
 
-    This will allow us to properly handle after_dependencies.
+    This allow us to:
+     - Properly handle after_dependencies.
+     - Keep track of domains which will load but have not yet finished loading
     """
     hass.data[DATA_SETUP_DONE] = {domain: asyncio.Event() for domain in domains}
 
@@ -265,7 +283,7 @@ async def _async_setup_component(
         await asyncio.sleep(0)
         await hass.config_entries.flow.async_wait_init_flow_finish(domain)
 
-        # Add to components before the async_setup
+        # Add to components before the entry.async_setup
         # call to avoid a deadlock when forwarding platforms
         hass.config.components.add(domain)