async def test_iterates_only_once():
"""When a credential succeeds, DefaultAzureCredential should use that credential thereafter, ignoring the others"""
unavailable_credential = Mock(get_token=Mock(side_effect=CredentialUnavailableError(message="...")))
successful_credential = Mock(get_token=Mock(return_value=get_completed_future(AccessToken("***", 42))))
credential = DefaultAzureCredential()
credential.credentials = [
unavailable_credential,
successful_credential,
Mock(get_token=Mock(side_effect=Exception("iteration didn't stop after a credential provided a token"))),
]
for n in range(3):
await credential.get_token("scope")
assert unavailable_credential.get_token.call_count == 1
assert successful_credential.get_token.call_count == n + 1
