From 76ae6958ede8f157d1a6d79fbe69926854945ac4 Mon Sep 17 00:00:00 2001
From: Will Moss <wbmoss@gmail.com>
Date: Sat, 28 Mar 2026 08:55:55 -0700
Subject: [PATCH] Handle Oauth2 ImplementationUnavailableError in
 google_assistant_sdk (#166649)

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
---
 .../google_assistant_sdk/__init__.py          |  9 ++++++++-
 .../google_assistant_sdk/strings.json         |  3 +++
 .../google_assistant_sdk/test_init.py         | 20 +++++++++++++++++++
 3 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/homeassistant/components/google_assistant_sdk/__init__.py b/homeassistant/components/google_assistant_sdk/__init__.py
index 8d98da2fe4e..d972a4d8d3f 100644
--- a/homeassistant/components/google_assistant_sdk/__init__.py
+++ b/homeassistant/components/google_assistant_sdk/__init__.py
@@ -12,6 +12,7 @@ from homeassistant.core import HomeAssistant
 from homeassistant.exceptions import ConfigEntryAuthFailed, ConfigEntryNotReady
 from homeassistant.helpers import config_validation as cv, discovery, intent
 from homeassistant.helpers.config_entry_oauth2_flow import (
+    ImplementationUnavailableError,
     OAuth2Session,
     async_get_config_entry_implementation,
 )
@@ -47,7 +48,13 @@ async def async_setup_entry(
     hass: HomeAssistant, entry: GoogleAssistantSDKConfigEntry
 ) -> bool:
     """Set up Google Assistant SDK from a config entry."""
-    implementation = await async_get_config_entry_implementation(hass, entry)
+    try:
+        implementation = await async_get_config_entry_implementation(hass, entry)
+    except ImplementationUnavailableError as err:
+        raise ConfigEntryNotReady(
+            translation_domain=DOMAIN,
+            translation_key="oauth2_implementation_unavailable",
+        ) from err
     session = OAuth2Session(hass, entry, implementation)
     try:
         await session.async_ensure_token_valid()
diff --git a/homeassistant/components/google_assistant_sdk/strings.json b/homeassistant/components/google_assistant_sdk/strings.json
index 8a509430c53..b1997ff06b3 100644
--- a/homeassistant/components/google_assistant_sdk/strings.json
+++ b/homeassistant/components/google_assistant_sdk/strings.json
@@ -48,6 +48,9 @@
     "grpc_error": {
       "message": "Failed to communicate with Google Assistant"
     },
+    "oauth2_implementation_unavailable": {
+      "message": "[%key:common::exceptions::oauth2_implementation_unavailable::message%]"
+    },
     "reauth_required": {
       "message": "Credentials are invalid, re-authentication required"
     }
diff --git a/tests/components/google_assistant_sdk/test_init.py b/tests/components/google_assistant_sdk/test_init.py
index e45037a19bd..d214723fcfc 100644
--- a/tests/components/google_assistant_sdk/test_init.py
+++ b/tests/components/google_assistant_sdk/test_init.py
@@ -16,6 +16,9 @@ from homeassistant.components.google_assistant_sdk.const import SUPPORTED_LANGUA
 from homeassistant.config_entries import ConfigEntryState
 from homeassistant.core import Context, HomeAssistant
 from homeassistant.exceptions import HomeAssistantError, ServiceValidationError
+from homeassistant.helpers.config_entry_oauth2_flow import (
+    ImplementationUnavailableError,
+)
 from homeassistant.setup import async_setup_component
 
 from .conftest import ComponentSetup, ExpectedCredentials
@@ -492,3 +495,20 @@ async def test_conversation_agent_language_changed(
     mock_text_assistant.assert_has_calls([call(ExpectedCredentials(), "es-ES")])
     mock_text_assistant.assert_has_calls([call().assist(text1)])
     mock_text_assistant.assert_has_calls([call().assist(text2)])
+
+
+async def test_oauth_implementation_not_available(
+    hass: HomeAssistant,
+    config_entry: MockConfigEntry,
+) -> None:
+    """Test that unavailable OAuth implementation raises ConfigEntryNotReady."""
+    config_entry.add_to_hass(hass)
+
+    with patch(
+        "homeassistant.components.google_assistant_sdk.async_get_config_entry_implementation",
+        side_effect=ImplementationUnavailableError,
+    ):
+        await hass.config_entries.async_setup(config_entry.entry_id)
+        await hass.async_block_till_done()
+
+    assert config_entry.state is ConfigEntryState.SETUP_RETRY