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//! A multi map implementation which also keeps the //! total order of inserted elements. I.e. if you //! insert `(k1, v1)` then `(k2, v2)` then `(k1, v3)`. //! The order when iterating over it will be exact this //! insertion order. Through there is an `grouped_values` //! method returning a iterator over the values grouped //! by key, instead of iteration order. //! //! The map makes sure that normal iteration is roughly //! as fast a iterating over a vector but using `get` to //! get a (group of) values is also roughly as fast as //! using `get` on a `HashMap`. The draw back is that //! insertion is a bit slower. //! //! Note that this implementation is made for values //! which dereference to the actually relevant values. //! It is also temporary limited to values which implement //! `DerefMut`, this can be lifted in the future. (I.e. //! currently `Box<T>` is supported but `Rc<T>` can be //! supported in the future just not for `_mut` methods). //! When accessing the map references to the inner values //! are returned (e.g. with a `Box<T>` references to `&T`/`&mut T` //! are returned and the `Box` is not accessible). //! //! Because of implementation details it is required that //! the value containers implement `StableDeref`. Note that //! this multi map can, or more precisely is made to, handle //! unsized values like trait object or slices. //! //! # State of Implementation //! //! Currently a lot of possible and useful methods are //! missing, take a look at the readme for more details. //! Through core methods like `insert`, `get`, `get_mut` //! and multiple iterators are implemented. //! //! Also currently it is limited to `StableDeref + DerefMut` //! but this is only needed for `_mut` methods. //! //! # Example //! //! see the example directories `from_readme.rs` example, //! which is also present in the README. //! //! # Implementation Details //! //! This implementation internally has a `Vec` and //! a `HashMap`. The `Vec` contains key-value pairs //! and "owns" the values. It is used for simple //! iteration and keeps the insertion order. The //! `HashMap` is a map from keys to vectors of //! pointers to inner values. And represents //! the multi map part. The code makes sure that //! only pointers are in the hash map iff their //! "owned" value is in the `Vec` at _any_ part //! of execution, even during insertion. This is //! needed to make sure that this type is unwind //! safe. Also to make sure that the pointers to //! the inner values are always valid the values //! have to implement `StableDeref`, so even if //! the vec is moved/resized the pointers stay //! valid as they don't point into the vec, but //! to the inner value the value in the vec points //! to. In turn this also means that mutable references //! to the containers/values should _never_ be exposed, //! through mutable references to the inner values //! can be exposed. //! //! Note that for ease of implementation only Copy //! keys are allowed, this should be improved on in //! later versions. //! extern crate stable_deref_trait; extern crate vec_drain_where; use std::collections::HashMap; use std::{vec, slice}; use std::hash::Hash; use std::cmp::{Eq, PartialEq}; use std::iter::{ Extend, FromIterator }; use std::fmt::{self, Debug}; use std::ops::DerefMut; use stable_deref_trait::StableDeref; use self::utils::DebugIterableOpaque; pub use self::iter::*; pub use self::entry::*; pub use self::map_iter::*; #[macro_use] mod utils; mod iter; mod entry; mod map_iter; // # SAFETY constraints (internal): // // - the ptr. contained in map_access have to be always valid, // code adding elements should first add them to `vec_data`, // and then to `map_access` code removing elements should // first remove them from `map_access` and then from `vec_data`. // // - giving out references to data always requires `self` to be // borrowed by the same kind of reference, a function giving // out references (either direct or transitive) should either // only use `vec_data` or `map_access` but not both, especially // so wrt. `&mut` (I.e. to use the contained `*mut T`'s as // `&mut T` it's required to `&mut` borrow the map. // // - UNDER ANY CIRCUMSTANCE NEVER return a mutable reference to the // data container (`&mut V`) in difference to a `&mut T`/`&mut V::Target` // it can override the container invalidating the `StableDeref` assumptions. // // // ## StableDeref assumptions // // - reminder: containers implementing `StableDeref` deref always to the same // memory address as long as the container itself is not mutated (but // even if the data on the address is mutated) // // - reminder: as we keep pointers directly to the data we can't allow any // mutation of the container // // - reminder: implementing `StableDeref` for a trait which on a safety level // relies on side-effects (e.g. using inner mutability) in deref is unsafe // /// A multi map with keeps the total ordering of inserted elements /// /// The map is meant to contain values implementing `StableDeref`, /// methods like `get` and `iter` will iterate over the inner values /// referred to when dereferencing the values. /// /// The key is currently limited to values implementing Copy. /// /// See the module/crate level documentation for more details. /// /// # Unwind Safety /// /// This type is unwind + resume safe. /// Through in the unlikely case that a panic happens inside of /// a function like `insert`,`get` the resulting state might be /// inconsistent in a safe way, i.e. some values might be in the map, /// accessible during iteration but hey won't appear when using `get`. /// /// Note that this can only happen in a few rare cases: /// /// 1. `Vec::pop`/`Vec::reserve` panics /// 2. `HashMap::insert`/`HashMap::reserve` panics /// 3. for some reason `oom` does panic instead of aborting /// /// Which mainly can happen in mainly following cases: /// /// - the vector of key-value pairs tries to contain more then `isize::MAX` bytes /// - you use zero-sized values and overflow `usize` (which can't really happen as /// we store at last some data per inserting, i.e. you would overflow the vec first) /// /// Generally speaking you won't run into any of this in normal circumstances and if /// you do it's likely that you are close to a system wide `oom` anyway. pub struct TotalOrderMultiMap<K, V> where V: StableDeref + DerefMut, K: Hash + Eq + Copy { vec_data: Vec<(K, V)>, map_access: HashMap<K, Vec<*mut V::Target>>, } impl<K, V> Default for TotalOrderMultiMap<K, V> where K: Hash + Eq + Copy, V: StableDeref + DerefMut { fn default() -> Self { TotalOrderMultiMap { vec_data: Default::default(), map_access: Default::default() } } } // Note further implementations in sub-modules (entry.rs, iter.rs, ...) impl<K, V> TotalOrderMultiMap<K, V> where K: Hash+Eq+Copy, V: StableDeref + DerefMut { /// Create a new empty map. pub fn new() -> Self { Default::default() } /// Crate a new map with a given `capacity`. /// /// Note that this method will reserve the given /// capacity for the internal `Vec` and `HashMap`, /// but as it's a multi map it can not know how /// elements will be distributed, as such using /// `with_capacity` does _not_ guarantee that there /// are no allocations if less than `capacity` elements /// are inserted. Through it still can reduce the /// number of allocations needed. pub fn with_capacity(capacity: usize) -> Self { TotalOrderMultiMap { vec_data: Vec::with_capacity(capacity), map_access: HashMap::with_capacity(capacity), } } /// Returns the capacity (unreliable). /// /// This is not reliable as it only returns /// the capacity of the underlying `Vec` not /// considering the underlying `HashMap` or /// the `Vec` used to turn the map into a /// multi map. pub fn capacity(&self) -> usize { self.vec_data.capacity() } /// Reserves space for `n` additional elements. /// /// The reservation is done in both the internal /// `Vec` and `HashMap` but as the map is a multi /// map this method is less helpful as e.g. on a /// pure `Vec` or `HashMap` /// /// # Panics /// if the new allocation size overflows `usize` pub fn reserve(&mut self, additional: usize) { self.vec_data.reserve(additional); self.map_access.reserve(additional); } /// Reverses insertion order. /// /// After calling this the map will contains values /// as if they had been inserted in reversed order. /// /// This will affect both the iteration order of /// the fill map as well as the iteration order of /// values returned by `get`. pub fn reverse(&mut self) { self.vec_data.reverse(); for (_, val) in self.map_access.iter_mut() { val.reverse() } } /// Shrinks all internal containers to not contains any additional capacity. /// /// Whether or not memory is freed depends in the dens on the `shrink_to_fit` /// implementation of `Vec` and `HashMap` pub fn shrink_to_fit(&mut self) { self.vec_data.shrink_to_fit(); self.map_access.shrink_to_fit(); for (_, val) in self.map_access.iter_mut() { val.shrink_to_fit() } } /// Returns the total number of elements. pub fn len(&self) -> usize { self.vec_data.len() } /// Returns the total number of different keys. pub fn key_count(&self) -> usize { self.map_access.len() } /// Returns `true` if the map is empty. pub fn is_empty(&self) -> bool { self.vec_data.is_empty() } /// Empties this map. pub fn clear(&mut self) { self.map_access.clear(); self.vec_data.clear(); } /// Returns `true` if the key is contained in the map. /// /// Does not state how many values are associated with it. pub fn contains_key(&self, k: K) -> bool { self.map_access.contains_key(&k) } /// Returns values associated with the given key. /// /// If the key is not in the map this will return `None`. /// This also means that `EntryValues` has at last one /// element. pub fn get(&self, k: K) -> EntryValues<V::Target> { self.map_access.get(&k) .map(|vec| EntryValues::new(vec.iter())) .unwrap_or_else(|| EntryValues::empty()) } /// Returns mutable references associated with the given key. /// /// If the key is not in the map this will return `None`. /// This means the `EntryValuesMut` has at last one element. pub fn get_mut(&mut self, k: K) -> EntryValuesMut<V::Target> { self.map_access.get_mut(&k) .map(|vec| EntryValuesMut::new(vec.iter_mut())) .unwrap_or_else(|| EntryValuesMut::empty()) } /// Adds a value for a given key to the multi map. /// /// Returns access the all values already added to /// the key previously and this now added value /// through `EntryValuesMut` pub fn add(&mut self, key: K, value: V) -> EntryValuesMut<V::Target> { self.entry(key).add(value) } /// Sets the value associated with the given key. /// /// Values previously associated with the key are /// removed and returned. pub fn set(&mut self, key: K, value: V) -> Vec<V> { self.entry(key).set(value) } /// Remove and return the element last inserted. pub fn pop(&mut self) -> Option<(K, V)> { if let Some(&(k, ref val)) = self.vec_data.last() { Self::delete_last_inserted_from_map_with_same_ptr( &mut self.map_access, k, val); } else { return None; } self.vec_data.pop() } /// Keeps the first `to_len` inserted headers, removing the remaining ones. /// /// If `to_len` is equal or larger the current length nothing will happen. /// /// This won't affect the capacity. /// /// Which headers are keeps/removed depends on the insertion order of /// the headers in the map and is independent of the headers name or /// if there had been other headers with the same name inserted before/after. pub fn truncate(&mut self, to_len: usize) { if to_len >= self.len() { return; } { let mut to_delete_iter = self.vec_data[to_len..].iter(); while let Some(&(key, ref val)) = to_delete_iter.next_back() { Self::delete_last_inserted_from_map_with_same_ptr( &mut self.map_access, key, &val); } } self.vec_data.truncate(to_len); } /// Removes the last inserted value from the map_access's bucked for the given key. /// /// # Panic /// /// If the key doesn't correspond to a key in `map` or /// there is no ptr in the map equal to the ptr gotten /// from the given value this will panic. As this function /// is only used in places where key/value where given by /// the `vec_data` array and as such the situation can only /// appear if there is inconsistency in the map. /// /// # Design Notes /// /// The first pointer match in the relevant bucket _from the back_ /// is removed. Wrt. this it's good to be aware about two thinks: /// /// - for trait objects two pointers might point to the same address /// but be different thinks _but_ if they are different thinks /// their vtable part is not the same and as such they won't be /// equal for pointer equality /// /// - all thinks later in the same bucket had been inserted after /// this match (in total insertion order), which means that even /// if the first statement doesn't held it's okay to use this /// to remove the last "n" entries from the back/front. /// fn delete_last_inserted_from_map_with_same_ptr( map: &mut HashMap<K, Vec<*mut V::Target>>, key: K, val: &V::Target ) { let exp_ptr: *const V::Target = val; let bucket = map.get_mut(&key) .expect("[BUG] key in vec_data but not map_access"); let to_remove_idx = bucket.iter() .rposition(|ptr| *ptr as *const _ == exp_ptr) .expect("[BUG] no ptr for value in map_access"); bucket.remove(to_remove_idx); } //FIXME(UPSTREAM): use drain_filter instead of retain once stable then return Vec<V> // currently it returns true as long as at last one element is removed // once `drain_where` (or `drain_filter`) is stable it should be changed // to returning the removed values /// removes all values associated with the given key /// /// I.e. this removes all key-value pairs which key /// is equal to the given key. /// /// Returns true if at last one value was removed pub fn remove_all(&mut self, key_to_remove: K) -> bool { if let Some(_) = self.map_access.remove(&key_to_remove) { self.vec_data.retain(|&(key, _)| key != key_to_remove); true } else { false } } //TODO use iter_mut(), &mut V::Target /// retains only key value pairs for which `func` returns true /// /// All key-value pairs for with the predicate `func` returns /// false will be removed. pub fn retain<FN>(&mut self, mut func: FN) where FN: FnMut(K, &V::Target) -> bool { let mut to_remove_ptr = Vec::new(); let mut to_remove_idx = Vec::new(); for (idx, (key, val)) in self.iter().enumerate() { if !func(key, val) { let vptr: *const V::Target = val; to_remove_idx.push(idx); to_remove_ptr.push((key, vptr)); } } if to_remove_idx.is_empty() { return } for (key, ptr) in to_remove_ptr.into_iter() { let needs_key_removal; { if let Some(values) = self.map_access.get_mut(&key) { //TODO use remove_item once stable (rustc #40062) [inlined unstable def] match values.iter().position(|x| *x as *const _ == ptr) { Some(idx) => { values.remove(idx); }, None => unreachable!( "[BUG] inconsistent state, value is not in map_access but in vec_data") } needs_key_removal = values.is_empty(); } else { unreachable!( "[BUG] inconsistent state, value is not in map_access but in vec_data") } } if needs_key_removal { self.map_access.remove(&key); } } let mut idx = 0; //INDEX_SAFE: we shot circuited on empty let mut next_removal = to_remove_idx[0]; let mut to_remove_idx = &to_remove_idx[1..]; self.vec_data.retain(|_| { let retain = if idx == next_removal { if to_remove_idx.is_empty() { //we won't get to idx == 0 again next_removal = 0; } else { next_removal = to_remove_idx[0]; to_remove_idx = &to_remove_idx[1..]; } false } else { true }; idx += 1; retain }) } } impl<K, V> Debug for TotalOrderMultiMap<K, V> where K: Hash + Eq + Copy + Debug, V: StableDeref + DerefMut + Debug { fn fmt(&self, fter: &mut fmt::Formatter) -> fmt::Result { write!(fter, "TotalOrderMultiMap {{ ")?; for &(key, ref val_cont) in self.vec_data.iter() { write!(fter, "{:?} => {:?},", key, val_cont)?; } write!(fter, " }}") } } impl<K, V> Clone for TotalOrderMultiMap<K, V> where K: Hash + Eq + Copy, V: StableDeref + DerefMut + Clone { fn clone(&self) -> Self { let vec_data = Vec::with_capacity(self.vec_data.len()); let map_access = HashMap::with_capacity(self.map_access.len()); let mut map = TotalOrderMultiMap { map_access, vec_data}; for &(k, ref val) in self.vec_data.iter() { map.add(k, val.clone()); } map } } /// Compares for equality which does consider the insertion order impl<K, V> PartialEq<Self> for TotalOrderMultiMap<K, V> where K: Hash + Eq + Copy, V: StableDeref + DerefMut + PartialEq<V>, { #[inline] fn eq(&self, other: &Self) -> bool { self.vec_data.eq(&other.vec_data) } } /// Compares for equality which does consider the insertion order impl<K, V> Eq for TotalOrderMultiMap<K, V> where K: Hash + Eq + Copy, V: StableDeref + DerefMut + Eq, {} impl<K, V> IntoIterator for TotalOrderMultiMap<K, V> where K: Hash + Eq + Copy, V: StableDeref + DerefMut, { type Item = (K, V); type IntoIter = vec::IntoIter<(K, V)>; #[inline] fn into_iter(self) -> Self::IntoIter { let TotalOrderMultiMap { vec_data, map_access } = self; drop(map_access); vec_data.into_iter() } } impl<K, V> FromIterator<(K, V)> for TotalOrderMultiMap<K, V> where K: Hash + Eq + Copy, V: StableDeref + DerefMut, { fn from_iter<I: IntoIterator<Item=(K,V)>>(src: I) -> Self { let src_iter = src.into_iter(); let mut out = { let (min, _) = src_iter.size_hint(); if min > 0 { Self::with_capacity(min) } else { Self::default() } }; <Self as Extend<(K,V)>>::extend(&mut out, src_iter); out } } impl<K, V> Extend<(K, V)> for TotalOrderMultiMap<K, V> where K: Hash + Eq + Copy, V: StableDeref + DerefMut { fn extend<I>(&mut self, src: I) where I: IntoIterator<Item=(K,V)> { for (key, value) in src.into_iter() { self.add(key, value); } } } /// A type providing access to all values associated to "some key" /// /// This is mainly an iterator over values, or more precisely /// references to the inner value of the values. /// /// This is returned by `TotalOrderMultiMap.get`, so it does not /// contain the key as it should be known in any context where this /// type appear. /// pub struct EntryValues<'a, T: ?Sized+'a>{ /// Note: we might have `*mut T` value but we are only allowed to /// use them as `*const T` in this context!! inner_iter: Option<slice::Iter<'a, *mut T>>, } impl<'a, T> EntryValues<'a, T> where T: ?Sized + 'a { pub fn empty() -> Self { EntryValues { inner_iter: None } } fn new(inner_iter: slice::Iter<'a, *mut T>) -> Self { EntryValues { inner_iter: Some(inner_iter) } } } // This iterator can be cloned cheaply impl<'a, T: ?Sized + 'a> Clone for EntryValues<'a, T> { fn clone(&self) -> Self { EntryValues { inner_iter: self.inner_iter.clone(), } } } impl<'a, T: ?Sized + 'a> Iterator for EntryValues<'a, T> { type Item = &'a T; #[inline] fn next(&mut self) -> Option<Self::Item> { //SAFE: the pointers are guaranteed to be valid, at last for lifetime 'a self.inner_iter .as_mut() .map(|iter| iter.next().map(|&ptr| unsafe { &*ptr })) .unwrap_or(None) } #[inline] fn size_hint(&self) -> (usize, Option<usize>) { self.inner_iter .as_ref() .map(|iter| iter.size_hint()) .unwrap_or((0, Some(0))) } } impl<'a, T: ?Sized + 'a> ExactSizeIterator for EntryValues<'a, T> { #[inline] fn len(&self) -> usize { self.inner_iter .as_ref() .map(|iter| iter.len()) .unwrap_or(0) } } impl<'a, T> Debug for EntryValues<'a, T> where T: ?Sized + Debug + 'a { fn fmt(&self, fter: &mut fmt::Formatter) -> fmt::Result { let metoo = DebugIterableOpaque::new(self.clone()); fter.debug_struct("EntryValues") .field("inner_iter", &metoo) .finish() } } /// A type providing mut access to all values associated to "some key" /// /// This is mainly an iterator over values, or more precisely /// mut references to the inner value of the values. /// /// This is returned by `TotalOrderMultiMap.get_mut`, so it does not /// contain the key as it should be known in any context where this /// type appear. /// pub struct EntryValuesMut<'a, T: ?Sized+'a>{ inner_iter: Option<slice::IterMut<'a, *mut T>>, } impl<'a, T: ?Sized + 'a> From<EntryValuesMut<'a, T>> for EntryValues<'a, T> { fn from(valmut: EntryValuesMut<'a, T>) -> Self { let EntryValuesMut { inner_iter } = valmut; let inner_iter = inner_iter.map(|iter_mut| { let as_slice = iter_mut.into_slice(); as_slice.iter() }); EntryValues { inner_iter } } } impl<'a, T> EntryValuesMut<'a, T> where T: ?Sized + 'a { pub fn empty() -> Self { EntryValuesMut { inner_iter: None } } fn new(inner_iter: slice::IterMut<'a, *mut T>) -> Self { EntryValuesMut { inner_iter: Some(inner_iter) } } } impl<'a, T: ?Sized + 'a> Iterator for EntryValuesMut<'a, T> { type Item = &'a mut T; #[inline] fn next(&mut self) -> Option<Self::Item> { //SAFE: the pointers are guaranteed to be valid, at last for lifetime 'a self.inner_iter .as_mut() .map(|iter| iter.next().map(|&mut ptr| unsafe { &mut *ptr })) .unwrap_or(None) } #[inline] fn size_hint(&self) -> (usize, Option<usize>) { self.inner_iter .as_ref() .map(|iter| iter.size_hint()) .unwrap_or((0, Some(0))) } } impl<'a, T: ?Sized + 'a> ExactSizeIterator for EntryValuesMut<'a, T> { #[inline] fn len(&self) -> usize { self.inner_iter .as_ref() .map(|iter| iter.len()) .unwrap_or(0) } } impl<'a, T> Debug for EntryValuesMut<'a, T> where T: ?Sized + Debug + 'a { fn fmt(&self, fter: &mut fmt::Formatter) -> fmt::Result { fter.write_str("EntryValuesMut(..)") } } /// see `SendSyncHelper` unsafe impl<K, V> Send for TotalOrderMultiMap<K, V> where SyncSendHelper<K,V>: Send, V: StableDeref + DerefMut, K: Hash + Eq + Copy {} /// see `SendSyncHelper` unsafe impl<K, V> Sync for TotalOrderMultiMap<K, V> where SyncSendHelper<K,V>: Sync, V: StableDeref + DerefMut, K: Hash + Eq + Copy {} /// Delegate the job of deciding about Send, Sync to rustc (ignore this) /// /// only the *const V::Target is not default Send/Sync in TotalOrderMultiMap as /// it's a pointer, but we can ignore it as whenever we accessed a value through /// it we can argue that we could have accessed the value "just" through safe code. /// It would just have been slower. And using the fast path doesn't circumvent any /// safety mechanisms like e.g. lock guards. As such if this struct is `Send`/`Sync` /// than `TotalOrderMultiMap` can be `Send`/`Sync`, too. pub struct SyncSendHelper<K, V>{ _p: ::std::marker::PhantomData<(K, V)> } #[cfg(test)] mod test { use std::mem; use std::collections::HashSet; use super::*; // use std::sync::Arc; // fn arc_str(s: &str) -> Arc<str> { // <Arc<str> as From<String>>::from(s.to_owned()) // } #[test] fn convert_entry_values_mut_to_non_mut() { let mut map = TotalOrderMultiMap::new(); map.add("k1", "v1".to_owned()); let iter: EntryValues<_> = map.get_mut("k1").into(); assert_eq!( vec!["v1"], iter.collect::<Vec<_>>() ); } #[test] fn clone_works_fine() { let obj_single = Box::new("hy".to_owned()); let obj_multi_a = Box::new("there".to_owned()); let obj_multi_b = Box::new("so".to_owned()); // make sure the pointer are to the new addresses let mut used_addresses = HashSet::new(); used_addresses.insert(&*obj_single as *const String as usize); used_addresses.insert(&*obj_multi_a as *const String as usize); used_addresses.insert(&*obj_multi_b as *const String as usize); let mut map = TotalOrderMultiMap::with_capacity(10); map.add("k1", obj_single); map.add("k2", obj_multi_a); map.add("k2", obj_multi_b); let map2 = map.clone(); // "hide" map to make sure there // is no accidental missuse let __map = map; //check if the addresses are "new" addresses for val in map2.get("k1") { let ptr = val as *const String as usize; assert!(!used_addresses.contains(&ptr)); } for val in map2.get("k2") { let ptr = val as *const String as usize; assert!(!used_addresses.contains(&ptr)); } for (_k, v) in map2.iter() { let ptr = v as *const String as usize; assert!(!used_addresses.contains(&ptr)); // here we also make sure there are no collisions used_addresses.insert(ptr); } assert_eq!(used_addresses.len(), 2 * map2.len()); mem::drop(__map); mem::drop(map2); } #[test] fn aux_fns() { let mut map = TotalOrderMultiMap::with_capacity(10); assert_eq!(true, map.is_empty()); map.add("key1", Box::new(13u32)); assert_eq!(false, map.is_empty()); map.add("key2", Box::new(1)); assert_eq!(10, map.capacity()); assert_eq!(2, map.len()); map.shrink_to_fit(); assert_eq!(2, map.capacity()); // this is not reserve_exact so it can reserve more // than space for one element map.reserve(1); assert!(map.capacity() >= 3); map.add("key1", Box::new(44)); map.add("key1", Box::new(44)); assert_eq!(4, map.len()); assert!(map.capacity() >= 4); map.clear(); assert_eq!(true, map.is_empty()); assert_eq!(0, map.len()); } #[test] fn works_with_trait_objects() { use std::fmt::Debug; let mut map = TotalOrderMultiMap::<&'static str, Box<Debug>>::new(); map.add("hy", Box::new("h".to_owned())); map.add("hy", Box::new(2)); map.add("ho", Box::new("o".to_owned())); let view = map.values().collect::<Vec<_>>(); assert_eq!( "\"h\" 2 \"o\"", format!("{:?} {:?} {:?}", view[0], view[1], view[2]) ) } #[test] fn get_set() { let mut map = TotalOrderMultiMap::new(); let a = "a".to_owned(); map.add("k1", a.clone()); map.add("k1", a.clone()); map.add("k2", a.clone()); map.add("k3", "y".to_owned()); map.add("k4", "z".to_owned()); map.add("k4", "a".to_owned()); map.add("k1", "e".to_owned()); let val_k1 = map.get("k1"); assert_eq!(3, val_k1.len()); assert_eq!((3, Some(3)), val_k1.size_hint()); assert_eq!( ["a", "a", "e"], val_k1.collect::<Vec<_>>().as_slice() ); } #[test] fn get_mut() { let ka = "aa"; let kb = "bb"; let a: Box<u32> = Box::new(12u32); let b: Box<u32> = Box::new(13u32); let mut map = TotalOrderMultiMap::new(); map.add(ka, a); map.add(kb, b); { let mut a_vals = map.get_mut(ka); let ref_a = a_vals.next().unwrap(); *ref_a = 44; } assert_eq!(2, map.len()); assert_eq!(vec![44], map.get(ka).map(|v|*v).collect::<Vec<_>>()); assert_eq!(vec![13], map.get(kb).map(|v|*v).collect::<Vec<_>>()); assert_eq!(0, map.get(&ka[..1]).len()); } #[test] fn truncate_longer() { let mut map = TotalOrderMultiMap::new(); map.add("a", "hy".to_owned()); map.add("b", "ho".to_owned()); map.add("a", "urgs".to_owned()); map.truncate(10); assert_eq!( vec![("a", "hy"), ("b", "ho"), ("a", "urgs")], map.iter().collect::<Vec<_>>() ); assert_eq!( vec!["hy", "urgs"], map.get("a").collect::<Vec<_>>() ); assert_eq!( vec!["ho"], map.get("b").collect::<Vec<_>>() ); } #[test] fn truncate_a_view_elements() { let mut map = TotalOrderMultiMap::new(); map.add("a", "hy".to_owned()); map.add("b", "ho".to_owned()); map.add("a", "urgs".to_owned()); map.add("c", "cirgs".to_owned()); map.truncate(2); assert_eq!( vec![("a", "hy"), ("b", "ho")], map.iter().collect::<Vec<_>>() ); assert_eq!( vec!["hy"], map.get("a").collect::<Vec<_>>() ); assert_eq!( vec!["ho"], map.get("b").collect::<Vec<_>>() ); assert_eq!( Vec::<&'static str>::new(), map.get("c").collect::<Vec<_>>() ); } // Re-enabled on non DerefMut can be used again // #[test] // fn get_set() { // let mut map = TotalOrderMultiMap::new(); // let a = arc_str("a"); // let co_a = a.clone(); // let eq_a = arc_str("a"); // map.add("k1", a); // map.add("k1", co_a); // map.add("k1", eq_a.clone()); // map.add("k2", eq_a); // map.add("k3", arc_str("y")); // map.add("k4", arc_str("z")); // map.add("k4", arc_str("a")); // map.add("k1", arc_str("e")); // let val_k1 = map.get("k1"); // assert_eq!(true, val_k1.is_some()); // let val_k1 = val_k1.unwrap(); // assert_eq!(4, val_k1.len()); // assert_eq!((4,Some(4)), val_k1.size_hint()); // assert_eq!(["a", "a", "a", "e"], val_k1.collect::<Vec<_>>().as_slice()); // let val_k2 = map.get("k2"); // assert_eq!(true, val_k2.is_some()); // let val_k2 = val_k2.unwrap(); // assert_eq!(1, val_k2.len()); // assert_eq!((1,Some(1)), val_k2.size_hint()); // assert_eq!(["a"], val_k2.collect::<Vec<_>>().as_slice()); // assert_eq!( // ["a", "a", "a", "a", "y", "z", "a", "e" ], // map.values().collect::<Vec<_>>().as_slice() // ); // let mut expected = HashSet::new(); // expected.add(("k1", vec![ "a", "a", "a", "e" ])); // expected.add(("k2", vec![ "a" ])); // expected.add(("k3", vec![ "y" ])); // expected.add(("k4", vec![ "z", "a" ])); // assert_eq!( // expected, // map.group_iter() // .map(|giter| (giter.key(), giter.collect::<Vec<_>>()) ) // .collect::<HashSet<_>>() // ); // assert_eq!( // [ ("k1", "a"), ("k1", "a"), ("k1", "a"), ("k2", "a"), // ("k3", "y"), ("k4", "z"), ("k4", "a"), ("k1", "e")], // map.iter().collect::<Vec<_>>().as_slice() // ); // } #[test] fn pop() { let mut map = TotalOrderMultiMap::new(); map.add("k1", "hy".to_owned()); map.add("k2", "ho".to_owned()); map.add("k1", "last".to_owned()); let last = map.pop(); assert_eq!( Some(("k1", "last".to_owned())), last ); } // #[test] // fn get_mut() { // use std::sync::Arc; // use std::cell::RefCell; // let mut map = TotalOrderMultiMap::new(); // map.add("k1", Arc::new(RefCell::new(12))); // // let cell = map.get_mut("k1").unwrap().next().unwrap(); // *cell.borrow_mut() = 55; // // let exp_cell = RefCell::new(55); // assert_eq!( // [ ("k1", &exp_cell) ], // map.iter().collect::<Vec<_>>().as_slice() // ) // } #[test] fn reverse() { let mut map = TotalOrderMultiMap::new(); map.add("k1", "ok".to_owned()); map.add("k2", "why not?".to_owned()); map.reverse(); assert_eq!( [("k2", "why not?"), ("k1", "ok")], map.iter().collect::<Vec<_>>().as_slice() ); } #[test] fn remove_all() { let mut map = TotalOrderMultiMap::new(); map.add("k1", "ok".to_owned()); map.add("k2", "why not?".to_owned()); map.add("k1", "run".to_owned()); map.add("k2", "jump".to_owned()); let did_rm = map.remove_all("k1"); assert_eq!(true, did_rm); assert_eq!(false, map.remove_all("not_a_key")); assert_eq!( [("k2", "why not?"), ("k2", "jump")], map.iter().collect::<Vec<_>>().as_slice() ); } #[test] fn retain() { let mut map = TotalOrderMultiMap::new(); map.add("k1", "ok".to_owned()); map.add("k2", "why not?".to_owned()); map.add("k1", "run".to_owned()); map.add("k2", "uh".to_owned()); map.retain(|key, val| { assert!(key.len() == 2); val.len() > 2 }); assert_eq!( [("k2", "why not?"), ("k1", "run")], map.iter().collect::<Vec<_>>().as_slice() ); } //Test can only be re-enabled once non DerefMut values are supported again. // #[test] // fn retain_with_equal_pointers() { // let mut map = TotalOrderMultiMap::new(); // let v1 = arc_str("v1"); // map.add("k1", v1.clone()); // map.add("k2", v1.clone()); // map.add("k1", arc_str("v2")); // map.add("k1", v1); // let mut rem_count = 0; // map.retain(|_key, val| { // if rem_count >= 2 { return true; } // if &*val == "v1" { // rem_count += 1; // false // } else { // true // } // }); // assert_eq!( // [("k1", "v2"), ("k1", "v1")], // map.iter().collect::<Vec<_>>().as_slice() // ); // } trait AssertSend: Send {} impl<K: Send, V: Send> AssertSend for TotalOrderMultiMap<K, V> where V: StableDeref + DerefMut, K: Hash + Eq + Copy, V::Target: Sync {} trait AssertSync: Sync {} impl<K: Sync, V: Sync> AssertSync for TotalOrderMultiMap<K, V> where V: StableDeref + DerefMut, K: Hash + Eq + Copy, V::Target: Sync {} }