You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: dyngroup.rs
    path of file: ./repos/kanidm/server/lib/src/plugins
    
    the code of the file until where you have to start completion: use std::collections::BTreeMap;
use std::sync::Arc;

use kanidm_proto::internal::Filter as ProtoFilter;

use crate::filter::FilterInvalid;
use crate::prelude::*;
use crate::server::ServerPhase;

#[derive(Clone, Default)]
pub struct DynGroupCache {
    insts: BTreeMap<Uuid, Filter<FilterInvalid>>,
}

pub struct DynGroup;

impl DynGroup {
    #[allow(clippy::too_many_arguments)]
    fn apply_dyngroup_change(
        qs: &mut QueryServerWriteTransaction,
        candidate_tuples: &mut Vec<(Arc<EntrySealedCommitted>, EntryInvalidCommitted)>,
        affected_uuids: &mut Vec<Uuid>,
        expect: bool,
        ident_internal: &Identity,
        dyn_groups: &mut DynGroupCache,
        n_dyn_groups: &[&Entry<EntrySealed, EntryCommitted>],
    ) -> Result<(), OperationError> {
        /*
         * This triggers even if we are modifying the dyngroups account policy attributes, which
         * is allowed now. So we relax this, because systemprotection still blocks the creation
         * of dyngroups.
        if !ident.is_internal() {
            // It should be impossible to trigger this right now due to protected plugin.
            error!("It is currently an error to create a dynamic group");
            return Err(OperationError
    
    fn test_modify_dyngroup_into_non_matching_entry() {
        let e_dyn = entry_init!(
            (Attribute::Class, EntryClass::Object.to_value()),
            (Attribute::Class, EntryClass::Group.to_value()),
            (Attribute::Class, EntryClass::DynGroup.to_value()),
            (Attribute::Name, Value::new_iname("test_dyngroup")),
            (
                Attribute::DynGroupFilter,
                Value::JsonFilt(ProtoFilter::Eq(
                    Attribute::Name.to_string(),
                    "testgroup".to_string()
                ))
            )
        );

        let e_group: Entry<EntryInit, EntryNew> = entry_init!(
            (Attribute::Class, EntryClass::Group.to_value()),
            (Attribute::Name, Value::new_iname("testgroup")),
            (Attribute::Uuid, Value::Uuid(UUID_TEST_GROUP))
        );

        let preload = vec![e_dyn, e_group];

        run_modify_test!(
            Ok(()),
            preload,
            filter!(f_eq(Attribute::Name, PartialValue::new_iname("testgroup"))),
            ModifyList::new_list(vec![
                Modify::Purged(Attribute::Name.into(),),
                Modify::Present(Attribute::Name.into(), Value::new_iname("not_testgroup"))
            ]),
            None,
            |_| {},
            |qs: &mut QueryServerWriteTransaction| {
                let cands = qs
                    .internal_search(filter!(f_eq(
                        Attribute::Name,
                        PartialValue::new_iname("test_dyngroup")
                    )))
                    .expect("Internal search failure");

                let d_group = cands.get(0).expect("Unable to access group.");
                assert!(d_group.get_ava_set(Attribute::DynMember).is_none());
            }
        );
    }