Function _do_skips

lib/sqlalchemy/testing/plugin/plugin_base.py:747–787

(cls)

def _do_skips(cls):
    reasons = []
    all_configs = _possible_configs_for_cls(cls, reasons)

    if getattr(cls, "__skip_if__", False):
        for c in getattr(cls, "__skip_if__"):
            if c():
                config.skip_test(
                    "'%s' skipped by %s" % (cls.__name__, c.__name__)
                )

    if not all_configs:
        msg = "'%s.%s' unsupported on any DB implementation %s%s" % (
            cls.__module__,
            cls.__name__,
            ", ".join(
                "'%s(%s)+%s'"
                % (
                    config_obj.db.name,
                    ".".join(
                        str(dig)
                        for dig in exclusions._server_version(config_obj.db)
                    ),
                    config_obj.db.driver,
                )
                for config_obj in config.Config.all_configs()
            ),
            ", ".join(reasons),
        )
        config.skip_test(msg)
    elif hasattr(cls, "__prefer_backends__"):
        non_preferred = set()
        spec = exclusions.db_spec(*util.to_list(cls.__prefer_backends__))
        for config_obj in all_configs:
            if not spec(config_obj):
                non_preferred.add(config_obj)
        if all_configs.difference(non_preferred):
            all_configs.difference_update(non_preferred)

    if config._current not in all_configs:
        _setup_config(all_configs.pop(), cls)


def _setup_config(config_obj, ctx):