fix: add SAML challenge to reauth (#819)

* fix: add SAML challenge to reauth

* add enable_reauth_refresh flag

* address comments

* fix unit test

* address comments

* update

* update

* update

* update

* 🦉 Updates from OwlBot

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Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>
Co-authored-by: Tres Seaver <tseaver@palladion.com>
diff --git a/tests/oauth2/test_credentials.py b/tests/oauth2/test_credentials.py
index 4a7f66e..b6a80e3 100644
--- a/tests/oauth2/test_credentials.py
+++ b/tests/oauth2/test_credentials.py
@@ -51,6 +51,7 @@
             client_id=cls.CLIENT_ID,
             client_secret=cls.CLIENT_SECRET,
             rapt_token=cls.RAPT_TOKEN,
+            enable_reauth_refresh=True,
         )
 
     def test_default_state(self):
@@ -149,6 +150,7 @@
             self.CLIENT_SECRET,
             None,
             self.RAPT_TOKEN,
+            True,
         )
 
         # Check that the credentials have the token and expiry
@@ -219,6 +221,7 @@
             self.CLIENT_SECRET,
             None,
             self.RAPT_TOKEN,
+            False,
         )
 
         # Check that the credentials have the token and expiry
@@ -422,6 +425,7 @@
             scopes=scopes,
             default_scopes=default_scopes,
             rapt_token=self.RAPT_TOKEN,
+            enable_reauth_refresh=True,
         )
 
         # Refresh credentials
@@ -436,6 +440,7 @@
             self.CLIENT_SECRET,
             scopes,
             self.RAPT_TOKEN,
+            True,
         )
 
         # Check that the credentials have the token and expiry
@@ -484,6 +489,7 @@
             client_secret=self.CLIENT_SECRET,
             default_scopes=default_scopes,
             rapt_token=self.RAPT_TOKEN,
+            enable_reauth_refresh=True,
         )
 
         # Refresh credentials
@@ -498,6 +504,7 @@
             self.CLIENT_SECRET,
             default_scopes,
             self.RAPT_TOKEN,
+            True,
         )
 
         # Check that the credentials have the token and expiry
@@ -549,6 +556,7 @@
             client_secret=self.CLIENT_SECRET,
             scopes=scopes,
             rapt_token=self.RAPT_TOKEN,
+            enable_reauth_refresh=True,
         )
 
         # Refresh credentials
@@ -563,6 +571,7 @@
             self.CLIENT_SECRET,
             scopes,
             self.RAPT_TOKEN,
+            True,
         )
 
         # Check that the credentials have the token and expiry
@@ -615,6 +624,7 @@
             client_secret=self.CLIENT_SECRET,
             scopes=scopes,
             rapt_token=self.RAPT_TOKEN,
+            enable_reauth_refresh=True,
         )
 
         # Refresh credentials
@@ -632,6 +642,7 @@
             self.CLIENT_SECRET,
             scopes,
             self.RAPT_TOKEN,
+            True,
         )
 
         # Check that the credentials have the token and expiry
@@ -731,6 +742,7 @@
         assert creds.refresh_token == info["refresh_token"]
         assert creds.token_uri == credentials._GOOGLE_OAUTH2_TOKEN_ENDPOINT
         assert creds.scopes is None
+        assert creds.rapt_token is None
 
         scopes = ["email", "profile"]
         creds = credentials.Credentials.from_authorized_user_file(
@@ -742,6 +754,18 @@
         assert creds.token_uri == credentials._GOOGLE_OAUTH2_TOKEN_ENDPOINT
         assert creds.scopes == scopes
 
+    def test_from_authorized_user_file_with_rapt_token(self):
+        info = AUTH_USER_INFO.copy()
+        file_path = os.path.join(DATA_DIR, "authorized_user_with_rapt_token.json")
+
+        creds = credentials.Credentials.from_authorized_user_file(file_path)
+        assert creds.client_secret == info["client_secret"]
+        assert creds.client_id == info["client_id"]
+        assert creds.refresh_token == info["refresh_token"]
+        assert creds.token_uri == credentials._GOOGLE_OAUTH2_TOKEN_ENDPOINT
+        assert creds.scopes is None
+        assert creds.rapt_token == "rapt"
+
     def test_to_json(self):
         info = AUTH_USER_INFO.copy()
         expiry = datetime.datetime(2020, 8, 14, 15, 54, 1)