def resolve_stack_name(source_stack_name, destination_stack_path):
    """
    Returns a stack's full name.

    A dependancy stack's name can be provided as either a full stack name, or
    as the file base name of a stack from the same environment.
    resolve_stack_name calculates the dependency's stack's full name from this.

    :param source_stack_name: The name of the stack with the parameter to be \
    resolved.
    :type source_stack_name: str
    :param destination_stack_path: The full or short name of the depenency \
    stack.
    :type destination_stack_path: str
    :returns: The stack's full name.
    :rtype: str
    """
    if "/" in destination_stack_path:
        return destination_stack_path
    else:
        source_stack_base_name = source_stack_name.rsplit("/", 1)[0]
        return "/".join([source_stack_base_name, destination_stack_path])