From 06f916cb60808edba0690a91430cef40a5fdfdd4 Mon Sep 17 00:00:00 2001 From: Vincent Prouillet Date: Mon, 14 May 2018 16:59:24 +0200 Subject: Add the preserve_order feature --- src/map.rs | 595 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 595 insertions(+) create mode 100644 src/map.rs (limited to 'src/map.rs') diff --git a/src/map.rs b/src/map.rs new file mode 100644 index 0000000..59ae24e --- /dev/null +++ b/src/map.rs @@ -0,0 +1,595 @@ +// Copyright 2017 Serde Developers +// +// Licensed under the Apache License, Version 2.0 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +//! A map of String to toml::Value. +//! +//! By default the map is backed by a [`BTreeMap`]. Enable the `preserve_order` +//! feature of toml-rs to use [`LinkedHashMap`] instead. +//! +//! [`BTreeMap`]: https://doc.rust-lang.org/std/collections/struct.BTreeMap.html +//! [`LinkedHashMap`]: https://docs.rs/linked-hash-map/*/linked_hash_map/struct.LinkedHashMap.html + +use serde::{de, ser}; +use std::fmt::{self, Debug}; +use value::Value; +use std::hash::Hash; +use std::iter::FromIterator; +use std::borrow::Borrow; +use std::ops; + +#[cfg(not(feature = "preserve_order"))] +use std::collections::{btree_map, BTreeMap}; + +#[cfg(feature = "preserve_order")] +use linked_hash_map::{self, LinkedHashMap}; + +/// Represents a JSON key/value type. +pub struct Map { + map: MapImpl, +} + +#[cfg(not(feature = "preserve_order"))] +type MapImpl = BTreeMap; +#[cfg(feature = "preserve_order")] +type MapImpl = LinkedHashMap; + +impl Map { + /// Makes a new empty Map. + #[inline] + pub fn new() -> Self { + Map { + map: MapImpl::new(), + } + } + + #[cfg(not(feature = "preserve_order"))] + /// Makes a new empty Map with the given initial capacity. + #[inline] + pub fn with_capacity(capacity: usize) -> Self { + // does not support with_capacity + let _ = capacity; + Map { + map: BTreeMap::new(), + } + } + + #[cfg(feature = "preserve_order")] + /// Makes a new empty Map with the given initial capacity. + #[inline] + pub fn with_capacity(capacity: usize) -> Self { + Map { + map: LinkedHashMap::with_capacity(capacity), + } + } + + /// Clears the map, removing all values. + #[inline] + pub fn clear(&mut self) { + self.map.clear() + } + + /// Returns a reference to the value corresponding to the key. + /// + /// The key may be any borrowed form of the map's key type, but the ordering + /// on the borrowed form *must* match the ordering on the key type. + #[inline] + pub fn get(&self, key: &Q) -> Option<&Value> + where + String: Borrow, + Q: Ord + Eq + Hash, + { + self.map.get(key) + } + + /// Returns true if the map contains a value for the specified key. + /// + /// The key may be any borrowed form of the map's key type, but the ordering + /// on the borrowed form *must* match the ordering on the key type. + #[inline] + pub fn contains_key(&self, key: &Q) -> bool + where + String: Borrow, + Q: Ord + Eq + Hash, + { + self.map.contains_key(key) + } + + /// Returns a mutable reference to the value corresponding to the key. + /// + /// The key may be any borrowed form of the map's key type, but the ordering + /// on the borrowed form *must* match the ordering on the key type. + #[inline] + pub fn get_mut(&mut self, key: &Q) -> Option<&mut Value> + where + String: Borrow, + Q: Ord + Eq + Hash, + { + self.map.get_mut(key) + } + + /// Inserts a key-value pair into the map. + /// + /// If the map did not have this key present, `None` is returned. + /// + /// If the map did have this key present, the value is updated, and the old + /// value is returned. The key is not updated, though; this matters for + /// types that can be `==` without being identical. + #[inline] + pub fn insert(&mut self, k: String, v: Value) -> Option { + self.map.insert(k, v) + } + + /// Removes a key from the map, returning the value at the key if the key + /// was previously in the map. + /// + /// The key may be any borrowed form of the map's key type, but the ordering + /// on the borrowed form *must* match the ordering on the key type. + #[inline] + pub fn remove(&mut self, key: &Q) -> Option + where + String: Borrow, + Q: Ord + Eq + Hash, + { + self.map.remove(key) + } + + /// Gets the given key's corresponding entry in the map for in-place + /// manipulation. + pub fn entry(&mut self, key: S) -> Entry + where + S: Into, + { + #[cfg(not(feature = "preserve_order"))] + use std::collections::btree_map::Entry as EntryImpl; + #[cfg(feature = "preserve_order")] + use linked_hash_map::Entry as EntryImpl; + + match self.map.entry(key.into()) { + EntryImpl::Vacant(vacant) => Entry::Vacant(VacantEntry { vacant: vacant }), + EntryImpl::Occupied(occupied) => Entry::Occupied(OccupiedEntry { occupied: occupied }), + } + } + + /// Returns the number of elements in the map. + #[inline] + pub fn len(&self) -> usize { + self.map.len() + } + + /// Returns true if the map contains no elements. + #[inline] + pub fn is_empty(&self) -> bool { + self.map.is_empty() + } + + /// Gets an iterator over the entries of the map. + #[inline] + pub fn iter(&self) -> Iter { + Iter { + iter: self.map.iter(), + } + } + + /// Gets a mutable iterator over the entries of the map. + #[inline] + pub fn iter_mut(&mut self) -> IterMut { + IterMut { + iter: self.map.iter_mut(), + } + } + + /// Gets an iterator over the keys of the map. + #[inline] + pub fn keys(&self) -> Keys { + Keys { + iter: self.map.keys(), + } + } + + /// Gets an iterator over the values of the map. + #[inline] + pub fn values(&self) -> Values { + Values { + iter: self.map.values(), + } + } +} + +impl Default for Map { + #[inline] + fn default() -> Self { + Map { + map: MapImpl::new(), + } + } +} + +impl Clone for Map { + #[inline] + fn clone(&self) -> Self { + Map { + map: self.map.clone(), + } + } +} + +impl PartialEq for Map { + #[inline] + fn eq(&self, other: &Self) -> bool { + self.map.eq(&other.map) + } +} + +/// Access an element of this map. Panics if the given key is not present in the +/// map. +impl<'a, Q: ?Sized> ops::Index<&'a Q> for Map +where + String: Borrow, + Q: Ord + Eq + Hash, +{ + type Output = Value; + + fn index(&self, index: &Q) -> &Value { + self.map.index(index) + } +} + +/// Mutably access an element of this map. Panics if the given key is not +/// present in the map. +impl<'a, Q: ?Sized> ops::IndexMut<&'a Q> for Map +where + String: Borrow, + Q: Ord + Eq + Hash, +{ + fn index_mut(&mut self, index: &Q) -> &mut Value { + self.map.get_mut(index).expect("no entry found for key") + } +} + +impl Debug for Map { + #[inline] + fn fmt(&self, formatter: &mut fmt::Formatter) -> Result<(), fmt::Error> { + self.map.fmt(formatter) + } +} + +impl ser::Serialize for Map { + #[inline] + fn serialize(&self, serializer: S) -> Result + where + S: ser::Serializer, + { + use serde::ser::SerializeMap; + let mut map = try!(serializer.serialize_map(Some(self.len()))); + for (k, v) in self { + try!(map.serialize_key(k)); + try!(map.serialize_value(v)); + } + map.end() + } +} + +impl<'de> de::Deserialize<'de> for Map { + #[inline] + fn deserialize(deserializer: D) -> Result + where + D: de::Deserializer<'de>, + { + struct Visitor; + + impl<'de> de::Visitor<'de> for Visitor { + type Value = Map; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("a map") + } + + #[inline] + fn visit_unit(self) -> Result + where + E: de::Error, + { + Ok(Map::new()) + } + + #[inline] + fn visit_map(self, mut visitor: V) -> Result + where + V: de::MapAccess<'de>, + { + let mut values = Map::new(); + + while let Some((key, value)) = try!(visitor.next_entry()) { + values.insert(key, value); + } + + Ok(values) + } + } + + deserializer.deserialize_map(Visitor) + } +} + +impl FromIterator<(String, Value)> for Map { + fn from_iter(iter: T) -> Self + where + T: IntoIterator, + { + Map { + map: FromIterator::from_iter(iter), + } + } +} + +impl Extend<(String, Value)> for Map { + fn extend(&mut self, iter: T) + where + T: IntoIterator, + { + self.map.extend(iter); + } +} + +macro_rules! delegate_iterator { + (($name:ident $($generics:tt)*) => $item:ty) => { + impl $($generics)* Iterator for $name $($generics)* { + type Item = $item; + #[inline] + fn next(&mut self) -> Option { + self.iter.next() + } + #[inline] + fn size_hint(&self) -> (usize, Option) { + self.iter.size_hint() + } + } + + impl $($generics)* DoubleEndedIterator for $name $($generics)* { + #[inline] + fn next_back(&mut self) -> Option { + self.iter.next_back() + } + } + + impl $($generics)* ExactSizeIterator for $name $($generics)* { + #[inline] + fn len(&self) -> usize { + self.iter.len() + } + } + } +} + +////////////////////////////////////////////////////////////////////////////// + +/// A view into a single entry in a map, which may either be vacant or occupied. +/// This enum is constructed from the [`entry`] method on [`Map`]. +/// +/// [`entry`]: struct.Map.html#method.entry +/// [`Map`]: struct.Map.html +pub enum Entry<'a> { + /// A vacant Entry. + Vacant(VacantEntry<'a>), + /// An occupied Entry. + Occupied(OccupiedEntry<'a>), +} + +/// A vacant Entry. It is part of the [`Entry`] enum. +/// +/// [`Entry`]: enum.Entry.html +pub struct VacantEntry<'a> { + vacant: VacantEntryImpl<'a>, +} + +/// An occupied Entry. It is part of the [`Entry`] enum. +/// +/// [`Entry`]: enum.Entry.html +pub struct OccupiedEntry<'a> { + occupied: OccupiedEntryImpl<'a>, +} + +#[cfg(not(feature = "preserve_order"))] +type VacantEntryImpl<'a> = btree_map::VacantEntry<'a, String, Value>; +#[cfg(feature = "preserve_order")] +type VacantEntryImpl<'a> = linked_hash_map::VacantEntry<'a, String, Value>; + +#[cfg(not(feature = "preserve_order"))] +type OccupiedEntryImpl<'a> = btree_map::OccupiedEntry<'a, String, Value>; +#[cfg(feature = "preserve_order")] +type OccupiedEntryImpl<'a> = linked_hash_map::OccupiedEntry<'a, String, Value>; + +impl<'a> Entry<'a> { + /// Returns a reference to this entry's key. + pub fn key(&self) -> &String { + match *self { + Entry::Vacant(ref e) => e.key(), + Entry::Occupied(ref e) => e.key(), + } + } + + /// Ensures a value is in the entry by inserting the default if empty, and + /// returns a mutable reference to the value in the entry. + pub fn or_insert(self, default: Value) -> &'a mut Value { + match self { + Entry::Vacant(entry) => entry.insert(default), + Entry::Occupied(entry) => entry.into_mut(), + } + } + + /// Ensures a value is in the entry by inserting the result of the default + /// function if empty, and returns a mutable reference to the value in the + /// entry. + pub fn or_insert_with(self, default: F) -> &'a mut Value + where + F: FnOnce() -> Value, + { + match self { + Entry::Vacant(entry) => entry.insert(default()), + Entry::Occupied(entry) => entry.into_mut(), + } + } +} + +impl<'a> VacantEntry<'a> { + /// Gets a reference to the key that would be used when inserting a value + /// through the VacantEntry. + #[inline] + pub fn key(&self) -> &String { + self.vacant.key() + } + + /// Sets the value of the entry with the VacantEntry's key, and returns a + /// mutable reference to it. + #[inline] + pub fn insert(self, value: Value) -> &'a mut Value { + self.vacant.insert(value) + } +} + +impl<'a> OccupiedEntry<'a> { + /// Gets a reference to the key in the entry. + #[inline] + pub fn key(&self) -> &String { + self.occupied.key() + } + + /// Gets a reference to the value in the entry. + #[inline] + pub fn get(&self) -> &Value { + self.occupied.get() + } + + /// Gets a mutable reference to the value in the entry. + #[inline] + pub fn get_mut(&mut self) -> &mut Value { + self.occupied.get_mut() + } + + /// Converts the entry into a mutable reference to its value. + #[inline] + pub fn into_mut(self) -> &'a mut Value { + self.occupied.into_mut() + } + + /// Sets the value of the entry with the `OccupiedEntry`'s key, and returns + /// the entry's old value. + #[inline] + pub fn insert(&mut self, value: Value) -> Value { + self.occupied.insert(value) + } + + /// Takes the value of the entry out of the map, and returns it. + #[inline] + pub fn remove(self) -> Value { + self.occupied.remove() + } +} + +////////////////////////////////////////////////////////////////////////////// + +impl<'a> IntoIterator for &'a Map { + type Item = (&'a String, &'a Value); + type IntoIter = Iter<'a>; + #[inline] + fn into_iter(self) -> Self::IntoIter { + Iter { + iter: self.map.iter(), + } + } +} + +/// An iterator over a toml::Map's entries. +pub struct Iter<'a> { + iter: IterImpl<'a>, +} + +#[cfg(not(feature = "preserve_order"))] +type IterImpl<'a> = btree_map::Iter<'a, String, Value>; +#[cfg(feature = "preserve_order")] +type IterImpl<'a> = linked_hash_map::Iter<'a, String, Value>; + +delegate_iterator!((Iter<'a>) => (&'a String, &'a Value)); + +////////////////////////////////////////////////////////////////////////////// + +impl<'a> IntoIterator for &'a mut Map { + type Item = (&'a String, &'a mut Value); + type IntoIter = IterMut<'a>; + #[inline] + fn into_iter(self) -> Self::IntoIter { + IterMut { + iter: self.map.iter_mut(), + } + } +} + +/// A mutable iterator over a toml::Map's entries. +pub struct IterMut<'a> { + iter: IterMutImpl<'a>, +} + +#[cfg(not(feature = "preserve_order"))] +type IterMutImpl<'a> = btree_map::IterMut<'a, String, Value>; +#[cfg(feature = "preserve_order")] +type IterMutImpl<'a> = linked_hash_map::IterMut<'a, String, Value>; + +delegate_iterator!((IterMut<'a>) => (&'a String, &'a mut Value)); + +////////////////////////////////////////////////////////////////////////////// + +impl IntoIterator for Map { + type Item = (String, Value); + type IntoIter = IntoIter; + #[inline] + fn into_iter(self) -> Self::IntoIter { + IntoIter { + iter: self.map.into_iter(), + } + } +} + +/// An owning iterator over a toml::Map's entries. +pub struct IntoIter { + iter: IntoIterImpl, +} + +#[cfg(not(feature = "preserve_order"))] +type IntoIterImpl = btree_map::IntoIter; +#[cfg(feature = "preserve_order")] +type IntoIterImpl = linked_hash_map::IntoIter; + +delegate_iterator!((IntoIter) => (String, Value)); + +////////////////////////////////////////////////////////////////////////////// + +/// An iterator over a toml::Map's keys. +pub struct Keys<'a> { + iter: KeysImpl<'a>, +} + +#[cfg(not(feature = "preserve_order"))] +type KeysImpl<'a> = btree_map::Keys<'a, String, Value>; +#[cfg(feature = "preserve_order")] +type KeysImpl<'a> = linked_hash_map::Keys<'a, String, Value>; + +delegate_iterator!((Keys<'a>) => &'a String); + +////////////////////////////////////////////////////////////////////////////// + +/// An iterator over a toml::Map's values. +pub struct Values<'a> { + iter: ValuesImpl<'a>, +} + +#[cfg(not(feature = "preserve_order"))] +type ValuesImpl<'a> = btree_map::Values<'a, String, Value>; +#[cfg(feature = "preserve_order")] +type ValuesImpl<'a> = linked_hash_map::Values<'a, String, Value>; + +delegate_iterator!((Values<'a>) => &'a Value); -- cgit v1.2.3