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//! A fast two-way bijective map. //! //! A `BiMap<L, R>` is a [bijective map] between values of type `L`, called left values, and values //! of type `R`, called right values. This means every left value is associated with exactly one //! right value and vice versa. Compare this to a [`HashMap`], where every key is associated with //! exactly one value but a value can be associated with more than one key. //! //! Internally, a `BiMap` is composed of two `HashMap`s, one for the left-to-right direction and //! one for right-to-left. As such, the big-O performance of the `get`, `remove`, `insert`, and //! `contains` methods are the same as those of a `HashMap`. //! //! As with `HashMap`, it is considered a logic error to modify a value's hash while it is in the //! `BiMap` using a `Cell`, `RefCell`, etc. //! //! # Examples //! //! ``` //! use bimap::BiMap; //! //! let mut elements = BiMap::new(); //! //! // insert chemicals and their corresponding symbols //! elements.insert("hydrogen", "H"); //! elements.insert("carbon", "C"); //! elements.insert("bromine", "Br"); //! elements.insert("neodymium", "Nd"); //! //! // retrieve chemical symbol by name (left to right) //! assert_eq!(elements.get_by_left(&"bromine"), Some(&"Br")); //! assert_eq!(elements.get_by_left(&"oxygen"), None); //! //! // retrieve name by chemical symbol (right to left) //! assert_eq!(elements.get_by_right(&"C"), Some(&"carbon")); //! assert_eq!(elements.get_by_right(&"Al"), None); //! //! // check membership //! assert!(elements.contains_left(&"hydrogen")); //! assert!(!elements.contains_right(&"He")); //! //! // remove elements //! assert_eq!(elements.remove_by_left(&"neodymium"), Some(("neodymium", "Nd"))); //! assert_eq!(elements.remove_by_right(&"Nd"), None); //! //! // iterate over elements //! for (left, right) in &elements { //! println!("the chemical symbol for {} is {}", left, right); //! } //! ``` //! //! ## Insertion and overwriting //! //! Consider the following example: //! //! ``` //! use bimap::BiMap; //! //! let mut bimap = BiMap::new(); //! bimap.insert('a', 1); //! bimap.insert('b', 1); // what to do here? //! ``` //! //! In order to maintain the bijection, the `BiMap` cannot have both `('a', 1)` and `('b', 1)` in //! the map. Otherwise, the right-value `1` would have two left values associated with it. Either //! we should allow the call to `insert` to go through and overwrite `('a', 1)`, or not let //! `('b', 1)` be inserted at all. `BiMap` allows for both possibilities. To insert with //! overwriting, use [`insert`], and to insert without overwriting, use [`insert_no_overwrite`]. //! The return type of `insert` is the `enum` [`Overwritten`], which indicates what values, if any, //! were overwritten; the return type of `insert_no_overwrite` is a boolean indicating if the //! insertion was successful. //! //! This is especially important when dealing with types that can be equal while having different //! data. Unlike a `HashMap`, which [doesn't update an equal key upon insertion], a `BiMap` updates //! both the left values and the right values. //! //! ``` //! use std::hash::{Hash, Hasher}; //! use bimap::{BiMap, Overwritten}; //! //! #[derive(Clone, Copy, Debug)] //! struct Foo { //! important: char, //! unimportant: u32, //! } //! //! // equality only depends on the important data //! impl PartialEq for Foo { //! fn eq(&self, other: &Foo) -> bool { //! self.important == other.important //! } //! } //! //! impl Eq for Foo {} //! //! // hash only depends on the important data //! impl Hash for Foo { //! fn hash<H: Hasher>(&self, state: &mut H) { //! self.important.hash(state); //! } //! } //! //! // create two Foos that are equal but have different data //! let foo1 = Foo { //! important: 'a', //! unimportant: 1, //! }; //! let foo2 = Foo { //! important: 'a', //! unimportant: 2, //! }; //! assert_eq!(foo1, foo2); //! //! let mut bimap = BiMap::new(); //! bimap.insert(foo1, 99); //! let overwritten = bimap.insert(foo2, 100); //! // foo1 is overwritten and returned; foo2 is in the bimap //! assert_eq!(overwritten, Overwritten::Left(foo1, 99)); //! assert_eq!(bimap.get_by_right(&100), Some(&foo2)); //! ``` //! //! [bijective map]: https://en.wikipedia.org/wiki/Bijection //! [doesn't update an equal key upon insertion]: //! https://doc.rust-lang.org/std/collections/index.html#insert-and-complex-keys //! [`HashMap`]: https://doc.rust-lang.org/std/collections/struct.HashMap.html //! [`insert`]: struct.BiMap.html#method.insert //! [`insert_no_overwrite`]: struct.BiMap.html#method.insert_no_overwrite //! [`Overwritten`]: enum.Overwritten.html use std::cmp; use std::collections::HashMap; use std::collections::hash_map; use std::fmt; use std::hash::Hash; use std::iter::{FromIterator, IntoIterator}; use std::ops::Deref; use std::rc::Rc; /// The previous left-right pairs, if any, that were overwritten by a call to the [`insert`] method /// of [`BiMap`]. /// /// [`insert`]: struct.BiMap.html#method.insert /// [`BiMap`]: struct.BiMap.html #[derive(Clone, Debug, Eq, PartialEq)] pub enum Overwritten<L, R> { /// Neither the left nor the right value previously existed in the `BiMap`. Neither, /// The left value existed in the `BiMap`, and the previous left-right pair is returned. Left(L, R), /// The right value existed in the `BiMap`, and the previous left-right pair is returned. Right(L, R), /// Both the left and the right value existed in the `BiMap`, but as part of separate pairs. /// The first tuple is the left-right pair of the previous left value, and the second is the /// left-right pair of the previous right value. Both((L, R), (L, R)), /// The left-right pair already existed in the `BiMap`, and the previous left-right pair is /// returned. Pair(L, R), } impl<L, R> Overwritten<L, R> { /// Returns a boolean indicating if the `Overwritten` variant implies any values were /// overwritten. /// /// This method is `true` for all variants other than `Neither`. /// /// # Examples /// /// ``` /// use bimap::{BiMap, Overwritten}; /// /// let mut bimap = BiMap::new(); /// assert!(!bimap.insert('a', 1).did_overwrite()); /// assert!(bimap.insert('a', 2).did_overwrite()); /// ``` pub fn did_overwrite(&self) -> bool { match self { &Overwritten::Neither => false, _ => true, } } } /// A two-way map between left values and right values. /// /// See the [module-level documentation] for more details and examples. /// /// [module-level documentation]: index.html pub struct BiMap<L, R> { left2right: HashMap<Rc<L>, Rc<R>>, right2left: HashMap<Rc<R>, Rc<L>>, } impl<L, R> BiMap<L, R> where L: Eq + Hash, R: Eq + Hash, { /// Creates an empty `BiMap`. /// /// # Examples /// /// ``` /// use bimap::BiMap; /// /// let mut bimap: BiMap<char, u32> = BiMap::new(); /// ``` pub fn new() -> BiMap<L, R> { BiMap::default() } /// Creates an empty `BiMap` with the given capacity. /// /// # Examples /// /// ``` /// use bimap::BiMap; /// /// let mut bimap: BiMap<char, u32> = BiMap::with_capacity(5); /// ``` pub fn with_capacity(capacity: usize) -> BiMap<L, R> { BiMap { left2right: HashMap::with_capacity(capacity), right2left: HashMap::with_capacity(capacity), } } /// Returns the number of left-right pairs in the map. /// /// # Examples /// /// ``` /// use bimap::BiMap; /// /// let mut bimap = BiMap::new(); /// bimap.insert('a', 1); /// bimap.insert('b', 2); /// bimap.insert('c', 3); /// assert_eq!(bimap.len(), 3); /// ``` pub fn len(&self) -> usize { self.left2right.len() } /// Returns `true` if the map contains no left-right pairs, and `false` otherwise. /// /// # Examples /// /// ``` /// use bimap::BiMap; /// /// let mut bimap = BiMap::new(); /// assert!(bimap.is_empty()); /// bimap.insert('a', 1); /// assert!(!bimap.is_empty()); /// bimap.remove_by_right(&1); /// assert!(bimap.is_empty()); /// ``` pub fn is_empty(&self) -> bool { self.len() == 0 } /// Removes all left-right pairs from the `BiMap`, but keeps the allocated memory for reuse. /// /// # Examples /// /// ``` /// use bimap::BiMap; /// /// let mut bimap = BiMap::new(); /// bimap.insert('a', 1); /// bimap.insert('b', 2); /// bimap.insert('c', 3); /// bimap.clear(); /// assert!(bimap.len() == 0); /// assert!(bimap.capacity() >= 3); /// ``` pub fn clear(&mut self) { self.left2right.clear(); self.right2left.clear(); } /// Returns a lower bound on the number of left-right pairs the `BiMap` can store without /// reallocating memory. /// /// # Examples /// /// ``` /// use bimap::BiMap; /// /// let mut bimap: BiMap<char, u32> = BiMap::with_capacity(5); /// assert!(bimap.capacity() >= 5); /// ``` pub fn capacity(&self) -> usize { cmp::min(self.left2right.capacity(), self.right2left.capacity()) } /// Create an iterator over the left-right pairs in the `BiMap` in arbitrary order. /// /// The iterator element type is `(&'a L, &'a R)`. /// /// # Examples /// /// ``` /// use bimap::BiMap; /// /// let mut bimap = BiMap::new(); /// bimap.insert('a', 1); /// bimap.insert('b', 2); /// bimap.insert('c', 3); /// /// for (left, right) in bimap.iter() { /// println!("({}, {})", left, right); /// } /// ``` pub fn iter<'a>(&'a self) -> Iter<'a, L, R> { Iter { inner: self.left2right.iter() } } /// Create an iterator over the left values in the `BiMap` in arbitrary order. /// /// The iterator element type is `&'a L`. /// /// # Examples /// /// ``` /// use bimap::BiMap; /// /// let mut bimap = BiMap::new(); /// bimap.insert('a', 1); /// bimap.insert('b', 2); /// bimap.insert('c', 3); /// /// for char_value in bimap.left_values() { /// println!("{}", char_value); /// } /// ``` pub fn left_values<'a>(&'a self) -> LeftValues<'a, L, R> { LeftValues { inner: self.left2right.iter() } } /// Create an iterator over the right values in the `BiMap` in arbitrary order. /// /// The iterator element type is `&'a R`. /// /// # Examples /// /// ``` /// use bimap::BiMap; /// /// let mut bimap = BiMap::new(); /// bimap.insert('a', 1); /// bimap.insert('b', 2); /// bimap.insert('c', 3); /// /// for int_value in bimap.right_values() { /// println!("{}", int_value); /// } /// ``` pub fn right_values<'a>(&'a self) -> RightValues<'a, L, R> { RightValues { inner: self.left2right.iter() } } /// Returns a reference to the right value corresponding to the given left value. /// /// # Examples /// /// ``` /// use bimap::BiMap; /// /// let mut bimap = BiMap::new(); /// bimap.insert('a', 1); /// assert_eq!(bimap.get_by_left(&'a'), Some(&1)); /// assert_eq!(bimap.get_by_left(&'z'), None); /// ``` pub fn get_by_left(&self, left: &L) -> Option<&R> { self.left2right.get(left).map(Deref::deref) } /// Returns a reference to the left value corresponding to the given right value. /// /// # Examples /// /// ``` /// use bimap::BiMap; /// /// let mut bimap = BiMap::new(); /// bimap.insert('a', 1); /// assert_eq!(bimap.get_by_right(&1), Some(&'a')); /// assert_eq!(bimap.get_by_right(&2), None); /// ``` pub fn get_by_right(&self, right: &R) -> Option<&L> { self.right2left.get(right).map(Deref::deref) } /// Returns `true` if the map contains the given left value and `false` otherwise. /// /// # Examples /// /// ``` /// use bimap::BiMap; /// /// let mut bimap = BiMap::new(); /// bimap.insert('a', 1); /// assert!(bimap.contains_left(&'a')); /// assert!(!bimap.contains_left(&'b')); /// ``` pub fn contains_left(&self, left: &L) -> bool { self.left2right.contains_key(left) } /// Returns `true` if the map contains the given right value and `false` otherwise. /// /// # Examples /// /// ``` /// use bimap::BiMap; /// /// let mut bimap: BiMap<char, u32> = BiMap::new(); /// bimap.insert('a', 1); /// assert!(bimap.contains_right(&1)); /// assert!(!bimap.contains_right(&2)); /// ``` pub fn contains_right(&self, right: &R) -> bool { self.right2left.contains_key(right) } /// Removes the left-right pair corresponding to the given left value. /// /// Returns the previous left-right pair if the map contained the left value and `None` /// otherwise. /// /// # Examples /// /// ``` /// use bimap::BiMap; /// /// let mut bimap = BiMap::new(); /// bimap.insert('a', 1); /// bimap.insert('b', 2); /// bimap.insert('c', 3); /// assert_eq!(bimap.len(), 3); /// assert_eq!(bimap.remove_by_left(&'b'), Some(('b', 2))); /// assert_eq!(bimap.len(), 2); /// assert_eq!(bimap.remove_by_left(&'b'), None); /// assert_eq!(bimap.len(), 2); /// ``` pub fn remove_by_left(&mut self, left: &L) -> Option<(L, R)> { self.left2right.remove(left).map(|right_rc| { let left_rc = self.right2left.remove(&right_rc).unwrap(); ( Rc::try_unwrap(left_rc).ok().unwrap(), Rc::try_unwrap(right_rc).ok().unwrap(), ) }) } /// Removes the left-right pair corresponding to the given right value. /// /// Returns the previous left-right pair if the map contained the right value and `None` /// otherwise. /// /// # Examples /// /// ``` /// use bimap::BiMap; /// /// let mut bimap = BiMap::new(); /// bimap.insert('a', 1); /// bimap.insert('b', 2); /// bimap.insert('c', 3); /// assert_eq!(bimap.len(), 3); /// assert_eq!(bimap.remove_by_right(&2), Some(('b', 2))); /// assert_eq!(bimap.len(), 2); /// assert_eq!(bimap.remove_by_right(&2), None); /// assert_eq!(bimap.len(), 2); /// ``` pub fn remove_by_right(&mut self, right: &R) -> Option<(L, R)> { self.right2left.remove(right).map(|left_rc| { let right_rc = self.left2right.remove(&left_rc).unwrap(); ( Rc::try_unwrap(left_rc).ok().unwrap(), Rc::try_unwrap(right_rc).ok().unwrap(), ) }) } /// Inserts the given left-right pair into the `BiMap`. /// /// Returns an `enum` `Overwritten` representing any left-right pairs that were overwritten by /// the call to `insert`. The example below details all possible `enum` variants that can be /// returned. /// /// # Warnings /// /// Somewhat paradoxically, calling `insert()` can actually reduce the size of the `BiMap`! /// This is because of the invariant that each left value maps to exactly one right value and /// vice versa. /// /// # Examples /// /// ``` /// use bimap::{BiMap, Overwritten}; /// /// let mut bimap = BiMap::new(); /// assert_eq!(bimap.len(), 0); // {} /// /// // no values are overwritten. /// assert_eq!(bimap.insert('a', 1), Overwritten::Neither); /// assert_eq!(bimap.len(), 1); // {'a' <> 1} /// /// // no values are overwritten. /// assert_eq!(bimap.insert('b', 2), Overwritten::Neither); /// assert_eq!(bimap.len(), 2); // {'a' <> 1, 'b' <> 2} /// /// // ('a', 1) already exists, so inserting ('a', 4) overwrites 'a', the left value. /// // the previous left-right pair ('a', 1) is returned. /// assert_eq!(bimap.insert('a', 4), Overwritten::Left('a', 1)); /// assert_eq!(bimap.len(), 2); // {'a' <> 4, 'b' <> 2} /// /// // ('b', 2) already exists, so inserting ('c', 2) overwrites 2, the right value /// // the previous left-right pair ('b', 2) is returned. /// assert_eq!(bimap.insert('c', 2), Overwritten::Right('b', 2)); /// assert_eq!(bimap.len(), 2); // {'a' <> 1, 'c' <> 2} /// /// // both ('a', 4) and ('c', 2) already exist, so inserting ('a', 2) overwrites both. /// // ('a', 4) has the overwritten left value ('a'), so it's the first tuple returned. /// // ('c', 2) has the overwritten right value (2), so it's the second tuple returned. /// assert_eq!(bimap.insert('a', 2), Overwritten::Both(('a', 4), ('c', 2))); /// assert_eq!(bimap.len(), 1); // {'a' <> 2} // bimap is smaller than before! /// /// // ('a', 2) already exists, so inserting ('a', 2) overwrites the pair. /// // the previous left-right pair ('a', 2) is returned. /// assert_eq!(bimap.insert('a', 2), Overwritten::Pair('a', 2)); /// assert_eq!(bimap.len(), 1); // {'a' <> 2} /// ``` pub fn insert(&mut self, left: L, right: R) -> Overwritten<L, R> { let retval = match (self.contains_left(&left), self.contains_right(&right)) { (false, false) => Overwritten::Neither, (true, false) => { let prev_pair = self.remove_by_left(&left).unwrap(); Overwritten::Left(prev_pair.0, prev_pair.1) } (false, true) => { let prev_pair = self.remove_by_right(&right).unwrap(); Overwritten::Right(prev_pair.0, prev_pair.1) } (true, true) => { if self.get_by_left(&left) == Some(&right) { let prev_pair = self.remove_by_left(&left).unwrap(); Overwritten::Pair(prev_pair.0, prev_pair.1) } else { let left_overwritten = self.remove_by_left(&left).unwrap(); let right_overwritten = self.remove_by_right(&right).unwrap(); Overwritten::Both(left_overwritten, right_overwritten) } } }; let left_rc = Rc::new(left); let right_rc = Rc::new(right); self.left2right.insert(left_rc.clone(), right_rc.clone()); self.right2left.insert(right_rc, left_rc); retval } /// Inserts the given left-right pair into the `BiMap` without overwriting any existing values. /// /// Returns a boolean representing if the pair was successfully inserted into the `BiMap`. If /// either value exists in the map, `false` is returned and the map is unchanged. Otherwise, /// the pair is inserted and `true` is returned. /// /// # Examples /// /// ``` /// use bimap::BiMap; /// /// let mut bimap = BiMap::new(); /// assert!(bimap.insert_no_overwrite('a', 1)); /// assert!(bimap.insert_no_overwrite('b', 2)); /// assert!(!bimap.insert_no_overwrite('a', 3)); /// assert!(!bimap.insert_no_overwrite('c', 2)); /// ``` pub fn insert_no_overwrite(&mut self, left: L, right: R) -> bool { if self.contains_left(&left) || self.contains_right(&right) { false } else { self.insert(left, right); true } } } impl<L, R> Clone for BiMap<L, R> where L: Eq + Hash + Clone, R: Eq + Hash + Clone, { fn clone(&self) -> BiMap<L, R> { self.iter().map(|(l, r)| (l.clone(), r.clone())).collect() } } impl<L, R> fmt::Debug for BiMap<L, R> where L: Eq + Hash + fmt::Debug, R: Eq + Hash + fmt::Debug, { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { write!(f, "{{")?; for (i, (left, right)) in self.left2right.iter().enumerate() { let comma = if i == 0 { "" } else { ", " }; write!(f, "{}{:?} <> {:?}", comma, left, right)?; } write!(f, "}}")?; Ok(()) } } impl<L, R> Default for BiMap<L, R> where L: Eq + Hash, R: Eq + Hash, { fn default() -> BiMap<L, R> { BiMap { left2right: HashMap::default(), right2left: HashMap::default(), } } } impl<L, R> Eq for BiMap<L, R> where L: Eq + Hash, R: Eq + Hash, { } impl<L, R> FromIterator<(L, R)> for BiMap<L, R> where L: Eq + Hash, R: Eq + Hash, { fn from_iter<I>(iter: I) -> BiMap<L, R> where I: IntoIterator<Item = (L, R)>, { let mut bimap = BiMap::new(); for (left, right) in iter { bimap.insert(left, right); } bimap } } impl<'a, L, R> IntoIterator for &'a BiMap<L, R> where L: Eq + Hash, R: Eq + Hash, { type Item = (&'a L, &'a R); type IntoIter = Iter<'a, L, R>; fn into_iter(self) -> Iter<'a, L, R> { self.iter() } } impl<L, R> IntoIterator for BiMap<L, R> where L: Eq + Hash, R: Eq + Hash, { type Item = (L, R); type IntoIter = IntoIter<L, R>; fn into_iter(self) -> IntoIter<L, R> { IntoIter { inner: self.left2right.into_iter() } } } impl<L, R> PartialEq for BiMap<L, R> where L: Eq + Hash, R: Eq + Hash, { fn eq(&self, other: &BiMap<L, R>) -> bool { self.left2right == other.left2right } } /// An owning iterator over the left-right pairs in a `BiMap`. /// /// This `struct` is created by the [`into_iter`] method of [`BiMap`]. /// /// [`into_iter`]: struct.BiMap.html#method.into_iter /// [`BiMap`]: struct.BiMap.html pub struct IntoIter<L, R> { inner: hash_map::IntoIter<Rc<L>, Rc<R>>, } impl<L, R> Iterator for IntoIter<L, R> { type Item = (L, R); fn next(&mut self) -> Option<(L, R)> { self.inner.next().map(|(l, r)| { ( Rc::try_unwrap(l).ok().unwrap(), Rc::try_unwrap(r).ok().unwrap(), ) }) } } /// An iterator over the left-right pairs in a `BiMap`. /// /// This `struct` is created by the [`iter`] method of [`BiMap`]. /// /// [`iter`]: struct.BiMap.html#method.iter /// [`BiMap`]: struct.BiMap.html pub struct Iter<'a, L, R> where L: 'a, R: 'a, { inner: hash_map::Iter<'a, Rc<L>, Rc<R>>, } impl<'a, L, R> Iterator for Iter<'a, L, R> { type Item = (&'a L, &'a R); fn next(&mut self) -> Option<(&'a L, &'a R)> { self.inner.next().map(|(left_rc, right_rc)| { (Deref::deref(left_rc), Deref::deref(right_rc)) }) } fn size_hint(&self) -> (usize, Option<usize>) { self.inner.size_hint() } } /// An iterator over the left values in a `BiMap`. /// /// This `struct` is created by the [`left_values`] method of [`BiMap`]. /// /// [`left_values`]: struct.BiMap.html#method.left_values /// [`BiMap`]: struct.BiMap.html pub struct LeftValues<'a, L, R> where L: 'a, R: 'a, { inner: hash_map::Iter<'a, Rc<L>, Rc<R>>, } impl<'a, L, R> Iterator for LeftValues<'a, L, R> { type Item = &'a L; fn next(&mut self) -> Option<&'a L> { self.inner.next().map(|(left_rc, _)| Deref::deref(left_rc)) } fn size_hint(&self) -> (usize, Option<usize>) { self.inner.size_hint() } } /// An iterator over the right values in a `BiMap`. /// /// This `struct` is created by the [`right_values`] method of [`BiMap`]. /// /// [`right_values`]: struct.BiMap.html#method.right_values /// [`BiMap`]: struct.BiMap.html pub struct RightValues<'a, L, R> where L: 'a, R: 'a, { inner: hash_map::Iter<'a, Rc<L>, Rc<R>>, } impl<'a, L, R> Iterator for RightValues<'a, L, R> { type Item = &'a R; fn next(&mut self) -> Option<&'a R> { self.inner.next().map( |(_, right_rc)| Deref::deref(right_rc), ) } fn size_hint(&self) -> (usize, Option<usize>) { self.inner.size_hint() } } #[cfg(test)] mod tests { use super::*; #[test] fn test_clone() { let mut bimap = BiMap::new(); bimap.insert('a', 1); bimap.insert('b', 2); let bimap2 = bimap.clone(); assert_eq!(bimap, bimap2); } #[test] fn test_deep_clone() { let mut bimap = BiMap::new(); bimap.insert('a', 1); bimap.insert('b', 2); let mut bimap2 = bimap.clone(); // would panic if clone() didn't deep clone bimap.insert('b', 5); bimap2.insert('a', 12); bimap2.remove_by_left(&'a'); bimap.remove_by_right(&2); } #[test] fn test_debug() { let mut bimap = BiMap::new(); bimap.insert('a', 1); assert_eq!("{'a' <> 1}", format!("{:?}", bimap)); bimap.insert('b', 2); let expected1 = "{'a' <> 1, 'b' <> 2}"; let expected2 = "{'b' <> 2, 'a' <> 1}"; let formatted = format!("{:?}", bimap); assert!(formatted == expected1 || formatted == expected2); } #[test] fn test_eq() { let mut bimap = BiMap::new(); assert_eq!(bimap, bimap); bimap.insert('a', 1); assert_eq!(bimap, bimap); bimap.insert('b', 2); assert_eq!(bimap, bimap); let mut bimap2 = BiMap::new(); assert_ne!(bimap, bimap2); bimap2.insert('a', 1); assert_ne!(bimap, bimap2); bimap2.insert('b', 2); assert_eq!(bimap, bimap2); bimap2.insert('c', 3); assert_ne!(bimap, bimap2); } #[test] fn test_from_iter() { let bimap = BiMap::from_iter(vec![ ('a', 1), ('b', 2), ('c', 3), ('b', 2), ('a', 4), ('b', 3), ]); let mut bimap2 = BiMap::with_capacity(3); bimap2.insert('a', 4); bimap2.insert('b', 3); assert_eq!(bimap, bimap2); } #[test] fn test_iter() { let mut bimap = BiMap::new(); bimap.insert('a', 1); bimap.insert('b', 2); bimap.insert('c', 3); let mut pairs = bimap.iter().map(|(c, i)| (*c, *i)).collect::<Vec<_>>(); pairs.sort(); assert_eq!(pairs, vec![('a', 1), ('b', 2), ('c', 3)]); } #[test] fn test_left_values() { let mut bimap = BiMap::new(); bimap.insert('a', 1); bimap.insert('b', 2); bimap.insert('c', 3); let mut left_values = bimap.left_values().cloned().collect::<Vec<_>>(); left_values.sort(); assert_eq!(left_values, vec!['a', 'b', 'c']) } #[test] fn test_right_values() { let mut bimap = BiMap::new(); bimap.insert('a', 1); bimap.insert('b', 2); bimap.insert('c', 3); let mut right_values = bimap.right_values().cloned().collect::<Vec<_>>(); right_values.sort(); assert_eq!(right_values, vec![1, 2, 3]) } }