When there is 1 member in the group and you want to generate a proof without passing the tree depth, there will be an error because tree depth 0 is not supported to generate a proof and one member is tree depth 0. It's true that in a group with 1 member there is no anonymity but for testing purposes it's better to also support tree depth 0 when generating a proof for groups with 1 member without passing the tree depth parameter.
Description
When there is 1 member in the group and you want to generate a proof without passing the tree depth, there will be an error because tree depth 0 is not supported to generate a proof and one member is tree depth 0. It's true that in a group with 1 member there is no anonymity but for testing purposes it's better to also support tree depth 0 when generating a proof for groups with 1 member without passing the tree depth parameter.
Tasks:
More context: https://github.com/semaphore-protocol/semaphore/issues/804