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use crate::block::{BlockCell, Item, ItemContent, ItemPosition, ItemPtr, Prelim};
use crate::types::array::ArrayEvent;
use crate::types::map::MapEvent;
use crate::types::text::TextEvent;
use crate::types::xml::{XmlEvent, XmlTextEvent};
use crate::types::{
Entries, Event, Events, Path, PathSegment, RootRef, SharedRef, TypePtr, TypeRef,
};
use crate::{
ArrayRef, Doc, MapRef, Observer, Origin, ReadTxn, Subscription, TextRef, TransactionMut, Value,
WriteTxn, XmlElementRef, XmlFragmentRef, XmlTextRef, ID,
};
use serde::{Deserialize, Serialize};
use std::borrow::Borrow;
use std::collections::{HashMap, HashSet, VecDeque};
use std::fmt::Formatter;
use std::hash::{Hash, Hasher};
use std::marker::PhantomData;
use std::ops::{Deref, DerefMut};
use std::ptr::NonNull;
use std::sync::Arc;
/// A wrapper around [Branch] cell, supplied with a bunch of convenience methods to operate on both
/// map-like and array-like contents of a [Branch].
#[repr(transparent)]
#[derive(Clone, Copy, Hash)]
pub struct BranchPtr(NonNull<Branch>);
impl BranchPtr {
pub(crate) fn trigger(
&self,
txn: &TransactionMut,
subs: HashSet<Option<Arc<str>>>,
) -> Option<Event> {
let e = self.make_event(subs)?;
if let Some(callbacks) = self.observers.callbacks() {
for fun in callbacks {
fun(txn, &e);
}
}
Some(e)
}
pub(crate) fn trigger_deep(&self, txn: &TransactionMut, e: &Events) {
if let Some(callbacks) = self.deep_observers.callbacks() {
for fun in callbacks {
fun(txn, e);
}
}
}
}
impl Into<TypePtr> for BranchPtr {
fn into(self) -> TypePtr {
TypePtr::Branch(self)
}
}
impl Into<Origin> for BranchPtr {
fn into(self) -> Origin {
let addr = self.0.as_ptr() as usize;
let bytes = addr.to_be_bytes();
Origin::from(bytes.as_ref())
}
}
impl AsRef<Branch> for BranchPtr {
fn as_ref(&self) -> &Branch {
self.deref()
}
}
impl AsMut<Branch> for BranchPtr {
fn as_mut(&mut self) -> &mut Branch {
self.deref_mut()
}
}
impl Deref for BranchPtr {
type Target = Branch;
fn deref(&self) -> &Self::Target {
unsafe { self.0.as_ref() }
}
}
impl DerefMut for BranchPtr {
fn deref_mut(&mut self) -> &mut Self::Target {
unsafe { self.0.as_mut() }
}
}
impl<'a> From<&'a mut Arc<Branch>> for BranchPtr {
fn from(branch: &'a mut Arc<Branch>) -> Self {
let ptr = NonNull::from(branch.as_ref());
BranchPtr(ptr)
}
}
impl<'a> From<&'a Arc<Branch>> for BranchPtr {
fn from(branch: &'a Arc<Branch>) -> Self {
let b: &Branch = &*branch;
let ptr = unsafe { NonNull::new_unchecked(b as *const Branch as *mut Branch) };
BranchPtr(ptr)
}
}
impl<'a> From<&'a Branch> for BranchPtr {
fn from(branch: &'a Branch) -> Self {
let ptr = unsafe { NonNull::new_unchecked(branch as *const Branch as *mut Branch) };
BranchPtr(ptr)
}
}
impl Into<Value> for BranchPtr {
/// Converts current branch data into a [Value]. It uses a type ref information to resolve,
/// which value variant is a correct one for this branch. Since branch represent only complex
/// types [Value::Any] will never be returned from this method.
fn into(self) -> Value {
match self.type_ref() {
TypeRef::Array => Value::YArray(ArrayRef::from(self)),
TypeRef::Map => Value::YMap(MapRef::from(self)),
TypeRef::Text => Value::YText(TextRef::from(self)),
TypeRef::XmlElement(_) => Value::YXmlElement(XmlElementRef::from(self)),
TypeRef::XmlFragment => Value::YXmlFragment(XmlFragmentRef::from(self)),
TypeRef::XmlText => Value::YXmlText(XmlTextRef::from(self)),
//TYPE_REFS_XML_HOOK => Value::YXmlHook(XmlHookRef::from(self)),
#[cfg(feature = "weak")]
TypeRef::WeakLink(_) => Value::YWeakLink(crate::WeakRef::from(self)),
_ => Value::UndefinedRef(self),
}
}
}
impl Eq for BranchPtr {}
#[cfg(not(test))]
impl PartialEq for BranchPtr {
fn eq(&self, other: &Self) -> bool {
std::ptr::eq(self.0.as_ptr(), other.0.as_ptr())
}
}
#[cfg(test)]
impl PartialEq for BranchPtr {
fn eq(&self, other: &Self) -> bool {
if NonNull::eq(&self.0, &other.0) {
true
} else {
let a: &Branch = self.deref();
let b: &Branch = other.deref();
a.eq(b)
}
}
}
impl std::fmt::Debug for BranchPtr {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
write!(f, "{:?}", self.id())
}
}
/// Branch describes a content of a complex Yrs data structures, such as arrays or maps.
pub struct Branch {
/// A pointer to a first block of a indexed sequence component of this branch node. If `None`,
/// it means that sequence is empty or a branch doesn't act as an indexed sequence. Indexed
/// sequences include:
///
/// - [Array]: all elements are stored as a double linked list, while the head of the list is
/// kept in this field.
/// - [XmlElement]: this field acts as a head to a first child element stored within current XML
/// node.
/// - [Text] and [XmlText]: this field point to a first chunk of text appended to collaborative
/// text data structure.
pub(crate) start: Option<ItemPtr>,
/// A map component of this branch node, used by some of the specialized complex types
/// including:
///
/// - [Map]: all of the map elements are based on this field. The value of each entry points
/// to the last modified value.
/// - [XmlElement]: this field stores attributes assigned to a given XML node.
pub(crate) map: HashMap<Arc<str>, ItemPtr>,
/// Unique identifier of a current branch node. It can be contain either a named string - which
/// means, this branch is a root-level complex data structure - or a block identifier. In latter
/// case it means, that this branch is a complex type (eg. Map or Array) nested inside of
/// another complex type.
pub(crate) item: Option<ItemPtr>,
/// For root-level types, this is a name of a branch.
pub(crate) name: Option<Arc<str>>,
/// A length of an indexed sequence component of a current branch node. Map component elements
/// are computed on demand.
pub block_len: u32,
pub content_len: u32,
/// An identifier of an underlying complex data type (eg. is it an Array or a Map).
pub(crate) type_ref: TypeRef,
pub(crate) observers: Observer<Event>,
pub(crate) deep_observers: Observer<Events>,
}
impl std::fmt::Debug for Branch {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
std::fmt::Display::fmt(self, f)
}
}
impl Eq for Branch {}
impl PartialEq for Branch {
fn eq(&self, other: &Self) -> bool {
self.item == other.item
&& self.start == other.start
&& self.map == other.map
&& self.block_len == other.block_len
&& self.type_ref == other.type_ref
}
}
impl Branch {
pub fn new(type_ref: TypeRef) -> Arc<Self> {
Arc::new(Self {
start: None,
map: HashMap::default(),
block_len: 0,
content_len: 0,
item: None,
name: None,
type_ref,
observers: Observer::default(),
deep_observers: Observer::default(),
})
}
pub fn is_deleted(&self) -> bool {
match self.item {
Some(ptr) => ptr.is_deleted(),
None => false,
}
}
pub fn id(&self) -> BranchID {
if let Some(ptr) = self.item {
BranchID::Nested(ptr.id)
} else if let Some(name) = &self.name {
BranchID::Root(name.clone())
} else {
unreachable!()
}
}
pub fn as_subdoc(&self) -> Option<Doc> {
let item = self.item?;
if let ItemContent::Doc(_, doc) = &item.content {
Some(doc.clone())
} else {
None
}
}
/// Returns an identifier of an underlying complex data type (eg. is it an Array or a Map).
pub fn type_ref(&self) -> &TypeRef {
&self.type_ref
}
pub(crate) fn repair_type_ref(&mut self, type_ref: TypeRef) {
if self.type_ref == TypeRef::Undefined {
self.type_ref = type_ref;
}
}
/// Returns a length of an indexed sequence component of a current branch node.
/// Map component elements are computed on demand.
pub fn len(&self) -> u32 {
self.block_len
}
pub fn content_len(&self) -> u32 {
self.content_len
}
/// Get iterator over (String, Block) entries of a map component of a current root type.
/// Deleted blocks are skipped by this iterator.
pub(crate) fn entries<'a, T: ReadTxn + 'a>(&'a self, txn: &'a T) -> Entries<'a, &'a T, T> {
Entries::from_ref(&self.map, txn)
}
/// Get iterator over Block entries of an array component of a current root type.
/// Deleted blocks are skipped by this iterator.
pub(crate) fn iter<'a, T: ReadTxn + 'a>(&'a self, txn: &'a T) -> Iter<'a, T> {
Iter::new(self.start.as_ref(), txn)
}
/// Returns a materialized value of non-deleted entry under a given `key` of a map component
/// of a current root type.
pub(crate) fn get<T: ReadTxn>(&self, _txn: &T, key: &str) -> Option<Value> {
let item = self.map.get(key)?;
if !item.is_deleted() {
item.content.get_last()
} else {
None
}
}
/// Given an `index` parameter, returns an item content reference which contains that index
/// together with an offset inside of this content, which points precisely to an `index`
/// location within wrapping item content.
/// If `index` was outside of the array component boundary of current branch node, `None` will
/// be returned.
pub(crate) fn get_at(&self, mut index: u32) -> Option<(&ItemContent, usize)> {
let mut ptr = self.start.as_ref();
while let Some(item) = ptr.map(ItemPtr::deref) {
let len = item.len();
if !item.is_deleted() && item.is_countable() {
if index < len {
return Some((&item.content, index as usize));
}
index -= len;
}
ptr = item.right.as_ref();
}
None
}
/// Removes an entry under given `key` of a map component of a current root type, returning
/// a materialized representation of value stored underneath if entry existed prior deletion.
pub(crate) fn remove(&self, txn: &mut TransactionMut, key: &str) -> Option<Value> {
let item = *self.map.get(key)?;
let prev = if !item.is_deleted() {
item.content.get_last()
} else {
None
};
txn.delete(item);
prev
}
/// Returns a first non-deleted item from an array component of a current root type.
pub(crate) fn first(&self) -> Option<&Item> {
let mut ptr = self.start.as_ref();
while let Some(item) = ptr.map(ItemPtr::deref) {
if item.is_deleted() {
ptr = item.right.as_ref();
} else {
return Some(item);
}
}
None
}
/// Given an `index` and start block `ptr`, returns a pair of block pointers.
///
/// If `index` happens to point inside of an existing block content, such block will be split at
/// position of an `index`. In such case left tuple value contains end of a block pointer on
/// a left side of an `index` and a pointer to a block directly on the right side of an `index`.
///
/// If `index` point to the end of a block and no splitting is necessary, tuple will return only
/// left side (beginning of a block), while right side will be `None`.
///
/// If `index` is outside of the range of an array component of current branch node, both tuple
/// values will be `None`.
fn index_to_ptr(
txn: &mut TransactionMut,
mut ptr: Option<ItemPtr>,
mut index: u32,
) -> (Option<ItemPtr>, Option<ItemPtr>) {
let encoding = txn.store.options.offset_kind;
while let Some(item) = ptr {
let content_len = item.content_len(encoding);
if !item.is_deleted() && item.is_countable() {
if index == content_len {
let left = ptr;
let right = item.right.clone();
return (left, right);
} else if index < content_len {
let index = if let ItemContent::String(s) = &item.content {
s.block_offset(index, encoding)
} else {
index
};
let right = txn.store.blocks.split_block(item, index, encoding);
if let Some(_) = item.moved {
if let Some(src) = right {
if let Some(&prev_dst) = txn.prev_moved.get(&item) {
txn.prev_moved.insert(src, prev_dst);
}
}
}
return (ptr, right);
}
index -= content_len;
}
ptr = item.right.clone();
}
(None, None)
}
/// Removes up to a `len` of countable elements from current branch sequence, starting at the
/// given `index`. Returns number of removed elements.
pub(crate) fn remove_at(&self, txn: &mut TransactionMut, index: u32, len: u32) -> u32 {
let mut remaining = len;
let start = { self.start };
let (_, mut ptr) = if index == 0 {
(None, start)
} else {
Branch::index_to_ptr(txn, start, index)
};
while remaining > 0 {
if let Some(item) = ptr {
let encoding = txn.store().options.offset_kind;
if !item.is_deleted() {
let content_len = item.content_len(encoding);
let (l, r) = if remaining < content_len {
let offset = if let ItemContent::String(s) = &item.content {
s.block_offset(remaining, encoding)
} else {
remaining
};
remaining = 0;
let new_right = txn.store.blocks.split_block(item, offset, encoding);
if let Some(_) = item.moved {
if let Some(src) = new_right {
if let Some(&prev_dst) = txn.prev_moved.get(&item) {
txn.prev_moved.insert(src, prev_dst);
}
}
}
(item, new_right)
} else {
remaining -= content_len;
(item, item.right.clone())
};
txn.delete(l);
ptr = r;
} else {
ptr = item.right.clone();
}
} else {
break;
}
}
len - remaining
}
/// Inserts a preliminary `value` into a current branch indexed sequence component at the given
/// `index`. Returns an item reference created as a result of this operation.
pub(crate) fn insert_at<V: Prelim>(
&self,
txn: &mut TransactionMut,
index: u32,
value: V,
) -> ItemPtr {
let (start, parent) = {
if index <= self.len() {
(self.start, BranchPtr::from(self))
} else {
panic!("Cannot insert item at index over the length of an array")
}
};
let (left, right) = if index == 0 {
(None, None)
} else {
Branch::index_to_ptr(txn, start, index)
};
let pos = ItemPosition {
parent: parent.into(),
left,
right,
index: 0,
current_attrs: None,
};
txn.create_item(&pos, value, None)
}
pub(crate) fn path(from: BranchPtr, to: BranchPtr) -> Path {
let parent = from;
let mut child = to;
let mut path = VecDeque::default();
while let Some(item) = &child.item {
if parent.item == child.item {
break;
}
let item_id = item.id.clone();
let parent_sub = item.parent_sub.clone();
child = *item.parent.as_branch().unwrap();
if let Some(parent_sub) = parent_sub {
// parent is map-ish
path.push_front(PathSegment::Key(parent_sub));
} else {
// parent is array-ish
let mut i = 0;
let mut c = child.start;
while let Some(ptr) = c {
if ptr.id() == &item_id {
break;
}
if !ptr.is_deleted() && ptr.is_countable() {
i += ptr.len();
}
c = ptr.right;
}
path.push_front(PathSegment::Index(i));
}
}
path
}
pub fn observe<F>(&mut self, f: F) -> Subscription
where
F: Fn(&TransactionMut, &Event) -> () + 'static,
{
self.observers.subscribe(f)
}
pub fn observe_deep<F>(&self, f: F) -> Subscription
where
F: Fn(&TransactionMut, &Events) -> () + 'static,
{
self.deep_observers.subscribe(f)
}
pub(crate) fn is_parent_of(&self, mut ptr: Option<ItemPtr>) -> bool {
while let Some(i) = ptr.as_deref() {
if let Some(parent) = i.parent.as_branch() {
if parent.deref() == self {
return true;
}
ptr = parent.item;
} else {
break;
}
}
false
}
pub(crate) fn make_event(&self, keys: HashSet<Option<Arc<str>>>) -> Option<Event> {
let self_ptr = BranchPtr::from(self);
let event = match self.type_ref() {
TypeRef::Array => Event::Array(ArrayEvent::new(self_ptr)),
TypeRef::Map => Event::Map(MapEvent::new(self_ptr, keys)),
TypeRef::Text => Event::Text(TextEvent::new(self_ptr)),
TypeRef::XmlElement(_) | TypeRef::XmlFragment => {
Event::XmlFragment(XmlEvent::new(self_ptr, keys))
}
TypeRef::XmlText => Event::XmlText(XmlTextEvent::new(self_ptr, keys)),
#[cfg(feature = "weak")]
TypeRef::WeakLink(_) => Event::Weak(crate::types::weak::WeakEvent::new(self_ptr)),
_ => return None,
};
Some(event)
}
}
pub(crate) struct Iter<'a, T> {
ptr: Option<&'a ItemPtr>,
_txn: &'a T,
}
impl<'a, T: ReadTxn> Iter<'a, T> {
fn new(ptr: Option<&'a ItemPtr>, txn: &'a T) -> Self {
Iter { ptr, _txn: txn }
}
}
impl<'a, T: ReadTxn> Iterator for Iter<'a, T> {
type Item = &'a Item;
fn next(&mut self) -> Option<Self::Item> {
let item = self.ptr.take()?;
self.ptr = item.right.as_ref();
Some(item)
}
}
/// A logical reference to a root-level shared collection. It can be shared across different
/// documents to reference the same logical type.
///
/// # Example
///
/// ```rust
/// use yrs::{Doc, RootRef, SharedRef, TextRef, Transact};
///
/// let root = TextRef::root("hello");
///
/// let doc1 = Doc::new();
/// let txt1 = root.get_or_create(&mut doc1.transact_mut());
///
/// let doc2 = Doc::new();
/// let txt2 = root.get_or_create(&mut doc2.transact_mut());
///
/// // instances of TextRef point to different heap objects
/// assert_ne!(txt1.as_ref() as *const _, txt2.as_ref() as *const _);
///
/// // logical descriptors of both TextRef are the same as they refer to the
/// // same logical entity
/// assert_eq!(txt1.hook(), txt2.hook());
/// ```
#[repr(transparent)]
#[derive(Debug, Clone, Ord, PartialOrd, Eq, PartialEq, Hash)]
pub struct Root<S> {
/// Unique identifier of root-level shared collection.
pub name: Arc<str>,
_tag: PhantomData<S>,
}
impl<S: RootRef> Root<S> {
/// Creates a new logical reference for a root-level shared collection of a given name and type.
/// Returned value can be used to resolve instances of root-level types by calling [Root::get]
/// or [Root::get_or_create].
pub fn new<N: Into<Arc<str>>>(name: N) -> Self {
Root {
name: name.into(),
_tag: PhantomData::default(),
}
}
/// Returns a reference to a shared root-level collection current [Root] represents, or creates
/// it if it wasn't instantiated before.
pub fn get_or_create<T: WriteTxn>(&self, txn: &mut T) -> S {
let store = txn.store_mut();
let branch = store.get_or_create_type(self.name.clone(), S::type_ref());
S::from(branch)
}
}
impl<S: SharedRef> Root<S> {
/// Returns a reference to a shared collection current [Root] represents, or returns `None` if
/// that collection hasn't been instantiated yet.
pub fn get<T: ReadTxn>(&self, txn: &T) -> Option<S> {
txn.store().get_type(self.name.clone()).map(S::from)
}
}
impl<S> Into<BranchID> for Root<S> {
fn into(self) -> BranchID {
BranchID::Root(self.name)
}
}
/// A logical reference used to represent a shared collection nested within another one. Unlike
/// [Root]-level types which cannot be deleted and exist eternally, [Nested] collections can be
/// added (therefore don't exist prior their instantiation) and deleted (so that any [SharedRef]
/// values referencing them become unsafe and can point to objects that no longer exists!).
///
/// Use [Nested::get] in order to materialize current nested logical reference into shared ref type.
///
/// # Example
///
/// ```rust
/// use yrs::{Doc, Map, Nested, SharedRef, TextPrelim, TextRef, Transact, WriteTxn};
///
/// let doc = Doc::new();
/// let mut txn = doc.transact_mut();
/// let root = txn.get_or_insert_map("root"); // root-level collection
/// let text = root.insert(&mut txn, "nested", TextPrelim::new("")); // nested collection
///
/// // convert nested TextRef into logical pointer
/// let nested: Nested<TextRef> = text.hook().into_nested().unwrap();
///
/// // logical reference can be used to retrieve accessible TextRef when its alive
/// assert_eq!(nested.get(&txn), Some(text));
///
/// // delete nested collection
/// root.remove(&mut txn, "nested");
///
/// // logical reference cannot resolve shared collections that have been deleted already
/// assert_eq!(nested.get(&txn), None);
/// ```
#[repr(transparent)]
#[derive(Debug, Clone, Ord, PartialOrd, Eq, PartialEq, Hash)]
pub struct Nested<S> {
pub id: ID,
_tag: PhantomData<S>,
}
impl<S> Nested<S> {
pub fn new(id: ID) -> Self {
Nested {
id,
_tag: PhantomData::default(),
}
}
}
impl<S: SharedRef> Nested<S> {
/// If current [Nested] logical reference points to an instantiated and not-deleted shared
/// collection, a reference to that collection will be returned.
/// If the referenced collection has been deleted or was not yet present in current transaction
/// scope i.e. due to missing update, a `None` will be returned.
pub fn get<T: ReadTxn>(&self, txn: &T) -> Option<S> {
let store = txn.store();
let block = store.blocks.get_block(&self.id)?;
if let BlockCell::Block(block) = block {
if let ItemContent::Type(branch) = &block.content {
if let Some(ptr) = branch.item {
if !ptr.is_deleted() {
return Some(S::from(BranchPtr::from(&*branch)));
}
}
}
}
None
}
}
impl<S> Into<BranchID> for Nested<S> {
fn into(self) -> BranchID {
BranchID::Nested(self.id)
}
}
/// A descriptor used to reference to shared collections by their unique logical identifiers,
/// which can be either [Root]-level collections or shared collections [Nested] into each other.
/// It can be resolved from any shared reference using [SharedRef::hook].
#[derive(Clone, Serialize, Deserialize)]
pub struct Hook<S> {
id: BranchID,
_tag: PhantomData<S>,
}
impl<S> Hook<S> {
/// Unique logical identifier of a shared collection.
#[inline]
pub fn id(&self) -> &BranchID {
&self.id
}
}
impl<S> std::fmt::Debug for Hook<S> {
fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
write!(f, "{:?}", self.id)
}
}
impl<S> Eq for Hook<S> {}
impl<S> PartialEq for Hook<S> {
fn eq(&self, other: &Self) -> bool {
self.id == other.id
}
}
impl<S> Hash for Hook<S> {
fn hash<H: Hasher>(&self, state: &mut H) {
self.id.hash(state)
}
}
impl<S: SharedRef> Hook<S> {
/// Returns a reference to a shared collection current hook points to, if it exists and
/// (in case of nested collections) has not been deleted.
///
/// # Example
///
/// ```rust
/// use yrs::{Hook, Doc, Map, MapRef, Nested, SharedRef, TextPrelim, TextRef, Transact, WriteTxn};
///
/// let doc = Doc::new();
/// let mut txn = doc.transact_mut();
/// let root = txn.get_or_insert_map("root"); // root-level collection
/// let nested = root.insert(&mut txn, "nested", TextPrelim::new("")); // nested collection
///
/// let root_hook: Hook<MapRef> = root.hook();
/// let nested_hook: Hook<TextRef> = nested.hook();
///
/// // hook can be used to retrieve collection reference as long as its alive
/// assert_eq!(nested_hook.get(&txn), Some(nested));
///
/// // after nested collection is deleted it can no longer be referenced
/// root.remove(&mut txn, "nested");
/// assert_eq!(nested_hook.get(&txn), None, "wtf");
///
/// // descriptors work also for root types
/// assert_eq!(root_hook.get(&txn), Some(root));
/// ```
pub fn get<T: ReadTxn>(&self, txn: &T) -> Option<S> {
let branch = self.id.get_branch(txn)?;
match branch.item {
Some(ptr) if ptr.is_deleted() => None,
_ => Some(S::from(branch)),
}
}
/// Attempts to convert current [Hook] type into [Nested] one.
/// Returns `None` if current descriptor doesn't reference a nested shared collection.
pub fn into_nested(self) -> Option<Nested<S>> {
match self.id {
BranchID::Nested(id) => Some(Nested::new(id)),
BranchID::Root(_) => None,
}
}
}
impl<S: RootRef> Hook<S> {
/// Attempts to convert current [Hook] type into [Root] one.
/// Returns `None` if current descriptor doesn't reference a root-level shared collection.
pub fn into_root(self) -> Option<Root<S>> {
match self.id {
BranchID::Root(name) => Some(Root::new(name)),
BranchID::Nested(_) => None,
}
}
}
impl<S> From<Root<S>> for Hook<S> {
fn from(root: Root<S>) -> Self {
Hook {
id: root.into(),
_tag: PhantomData::default(),
}
}
}
impl<S> From<Nested<S>> for Hook<S> {
fn from(nested: Nested<S>) -> Self {
Hook {
id: nested.into(),
_tag: PhantomData::default(),
}
}
}
impl<S> From<BranchID> for Hook<S> {
fn from(id: BranchID) -> Self {
Hook {
id,
_tag: PhantomData::default(),
}
}
}
impl<S> Into<BranchID> for Hook<S> {
fn into(self) -> BranchID {
self.id
}
}
/// An unique logical identifier of a shared collection. Can be shared across document boundaries
/// to reference to the same logical entity across different replicas of a document.
#[derive(Clone, Ord, PartialOrd, Eq, PartialEq, Hash, Serialize, Deserialize)]
pub enum BranchID {
Nested(ID),
Root(Arc<str>),
}
impl BranchID {
#[inline]
pub fn get_root<T: ReadTxn, K: Borrow<str>>(txn: &T, name: K) -> Option<BranchPtr> {
txn.store().get_type(name)
}
pub fn get_nested<T: ReadTxn>(txn: &T, id: &ID) -> Option<BranchPtr> {
let block = txn.store().blocks.get_block(id)?;
if let BlockCell::Block(block) = block {
if let ItemContent::Type(branch) = &block.content {
return Some(BranchPtr::from(&*branch));
}
}
None
}
pub fn get_branch<T: ReadTxn>(&self, txn: &T) -> Option<BranchPtr> {
match self {
BranchID::Root(name) => Self::get_root(txn, name.as_ref()),
BranchID::Nested(id) => Self::get_nested(txn, id),
}
}
}
impl std::fmt::Debug for BranchID {
fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
match self {
BranchID::Nested(id) => write!(f, "{}", id),
BranchID::Root(name) => write!(f, "'{}'", name),
}
}
}