style: Move lru_cache to its own crate.

One less crate pointlessly in components/.

Cargo.lock

@@ -1672,13 +1672,6 @@ name = "log"
 version = "0.3.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
-[[package]]
-name = "lru_cache"
-version = "0.0.1"
-dependencies = [
- "arrayvec 0.3.23 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "lzw"
 version = "0.10.0"
@@ -3180,7 +3173,6 @@ dependencies = [
  "kernel32-sys 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 0.2.9 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "lru_cache 0.0.1",
  "malloc_size_of 0.0.1",
  "malloc_size_of_derive 0.0.1",
  "matches 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -3206,6 +3198,7 @@ dependencies = [
  "style_traits 0.0.1",
  "time 0.1.37 (registry+https://github.com/rust-lang/crates.io-index)",
  "toml 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "uluru 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "unicode-bidi 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "unicode-segmentation 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "walkdir 1.0.7 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -3457,6 +3450,14 @@ name = "typeable"
 version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "uluru"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "arrayvec 0.3.23 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "unicase"
 version = "1.4.0"
@@ -4079,6 +4080,7 @@ dependencies = [
 "checksum traitobject 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "efd1f82c56340fdf16f2a953d7bda4f8fdffba13d93b00844c25572110b26079"
 "checksum truetype 0.26.0 (registry+https://github.com/rust-lang/crates.io-index)" = "acec30350633d6dac9dc1a625786b6cbe9150664be941aac2c35ad7199eab877"
 "checksum typeable 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "1410f6f91f21d1612654e7cc69193b0334f909dcf2c790c4826254fbb86f8887"
+"checksum uluru 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "cd28fce445fd48f4e2c10ab0d3d8f6a646b11fd2b05228fa94fc83cf69ad6e98"
 "checksum unicase 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "13a5906ca2b98c799f4b1ab4557b76367ebd6ae5ef14930ec841c74aed5f3764"
 "checksum unicase 2.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "2e01da42520092d0cd2d6ac3ae69eb21a22ad43ff195676b86f8c37f487d6b80"
 "checksum unicode-bidi 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "a6a2c4e3710edd365cd7e78383153ed739fa31af19f9172f72d3575060f5a43a"

components/lru_cache/Cargo.toml

@@ -1,13 +0,0 @@
-[package]
-name = "lru_cache"
-version = "0.0.1"
-authors = ["The Servo Project Developers"]
-license = "MPL-2.0"
-publish = false # We should publish this at some point
-
-[lib]
-name = "lru_cache"
-path = "lib.rs"
-
-[dependencies]
-arrayvec = "0.3.20"

components/lru_cache/lib.rs

@@ -1,238 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-//! A simple LRU cache.
-
-extern crate arrayvec;
-
-use arrayvec::{Array, ArrayVec};
-
-/// A LRU cache using a statically-sized array for storage.
-///
-/// The most-recently-used entry is at index `head`. The entries form a linked list, linked to each
-/// other by indices within the `entries` array.  After an entry is added to the array, its index
-/// never changes, so these links are never invalidated.
-pub struct LRUCache<T, A: Array<Item=Entry<T>>> {
-    entries: ArrayVec<A>,
-    /// Index of the first entry. If the cache is empty, ignore this field.
-    head: u16,
-    /// Index of the last entry. If the cache is empty, ignore this field.
-    tail: u16,
-}
-
-/// An opaque token used as an index into an LRUCache.
-pub struct CacheIndex(u16);
-
-/// An entry in an LRUCache.
-pub struct Entry<T> {
-    val: T,
-    /// Index of the previous entry. If this entry is the head, ignore this field.
-    prev: u16,
-    /// Index of the next entry. If this entry is the tail, ignore this field.
-    next: u16,
-}
-
-impl<T, A: Array<Item=Entry<T>>> Default for LRUCache<T, A> {
-    fn default() -> Self {
-        let cache = LRUCache {
-            entries: ArrayVec::new(),
-            head: 0,
-            tail: 0,
-        };
-        assert!(cache.entries.capacity() < u16::max_value() as usize, "Capacity overflow");
-        cache
-    }
-}
-
-impl<T, A: Array<Item=Entry<T>>> LRUCache<T, A> {
-    /// Returns the number of elements in the cache.
-    pub fn num_entries(&self) -> usize {
-        self.entries.len()
-    }
-
-    #[inline]
-    /// Touch a given entry, putting it first in the list.
-    pub fn touch(&mut self, idx: CacheIndex) {
-        if idx.0 != self.head {
-            self.remove(idx.0);
-            self.push_front(idx.0);
-        }
-    }
-
-    /// Returns the front entry in the list (most recently used).
-    pub fn front(&self) -> Option<&T> {
-        self.entries.get(self.head as usize).map(|e| &e.val)
-    }
-
-    /// Returns a mutable reference to the front entry in the list (most recently used).
-    pub fn front_mut(&mut self) -> Option<&mut T> {
-        self.entries.get_mut(self.head as usize).map(|e| &mut e.val)
-    }
-
-    /// Iterate over the contents of this cache, from more to less recently
-    /// used.
-    pub fn iter(&self) -> LRUCacheIterator<T, A> {
-        LRUCacheIterator {
-            pos: self.head,
-            done: self.entries.len() == 0,
-            cache: self,
-        }
-    }
-
-    /// Iterate mutably over the contents of this cache.
-    pub fn iter_mut(&mut self) -> LRUCacheMutIterator<T, A> {
-        LRUCacheMutIterator {
-            pos: self.head,
-            done: self.entries.len() == 0,
-            cache: self,
-        }
-    }
-
-    /// Performs a lookup on the cache with the given test routine. Touches
-    /// the result on a hit.
-    pub fn lookup<F, R>(&mut self, mut test_one: F) -> Option<R>
-    where
-        F: FnMut(&mut T) -> Option<R>
-    {
-        let mut result = None;
-        for (i, candidate) in self.iter_mut() {
-            if let Some(r) = test_one(candidate) {
-                result = Some((i, r));
-                break;
-            }
-        };
-
-        match result {
-            None => None,
-            Some((i, r)) => {
-                self.touch(i);
-                let front = self.front_mut().unwrap();
-                debug_assert!(test_one(front).is_some());
-                Some(r)
-            }
-        }
-    }
-
-    /// Insert a given key in the cache.
-    pub fn insert(&mut self, val: T) {
-        let entry = Entry { val, prev: 0, next: 0 };
-
-        // If the cache is full, replace the oldest entry. Otherwise, add an entry.
-        let new_head = if self.entries.len() == self.entries.capacity() {
-            let i = self.pop_back();
-            self.entries[i as usize] = entry;
-            i
-        } else {
-            self.entries.push(entry);
-            self.entries.len() as u16 - 1
-        };
-
-        self.push_front(new_head);
-    }
-
-    /// Remove an from the linked list.
-    ///
-    /// Note: This only unlinks the entry from the list; it does not remove it from the array.
-    fn remove(&mut self, i: u16) {
-        let prev = self.entries[i as usize].prev;
-        let next = self.entries[i as usize].next;
-
-        if i == self.head {
-            self.head = next;
-        } else {
-            self.entries[prev as usize].next = next;
-        }
-
-        if i == self.tail {
-            self.tail = prev;
-        } else {
-            self.entries[next as usize].prev = prev;
-        }
-    }
-
-    /// Insert a new entry at the head of the list.
-    fn push_front(&mut self, i: u16) {
-        if self.entries.len() == 1 {
-            self.tail = i;
-        } else {
-            self.entries[i as usize].next = self.head;
-            self.entries[self.head as usize].prev = i;
-        }
-        self.head = i;
-    }
-
-    /// Remove the last entry from the linked list. Returns the index of the removed entry.
-    ///
-    /// Note: This only unlinks the entry from the list; it does not remove it from the array.
-    fn pop_back(&mut self) -> u16 {
-        let old_tail = self.tail;
-        let new_tail = self.entries[old_tail as usize].prev;
-        self.tail = new_tail;
-        old_tail
-    }
-
-    /// Evict all elements from the cache.
-    pub fn evict_all(&mut self) {
-        self.entries.clear();
-    }
-}
-
-/// Immutable iterator over values in an LRUCache, from most-recently-used to least-recently-used.
-pub struct LRUCacheIterator<'a, T: 'a, A: 'a + Array<Item=Entry<T>>> {
-    cache: &'a LRUCache<T, A>,
-    pos: u16,
-    done: bool,
-}
-
-impl<'a, T, A> Iterator for LRUCacheIterator<'a, T, A>
-where T: 'a,
-      A: 'a + Array<Item=Entry<T>>
-{
-    type Item = (CacheIndex, &'a T);
-
-    fn next(&mut self) -> Option<Self::Item> {
-        if self.done { return None }
-
-        let entry = &self.cache.entries[self.pos as usize];
-
-        let index = CacheIndex(self.pos);
-        if self.pos == self.cache.tail {
-            self.done = true;
-        }
-        self.pos = entry.next;
-
-        Some((index, &entry.val))
-    }
-}
-
-/// Mutable iterator over values in an LRUCache, from most-recently-used to least-recently-used.
-pub struct LRUCacheMutIterator<'a, T: 'a, A: 'a + Array<Item=Entry<T>>> {
-    cache: &'a mut LRUCache<T, A>,
-    pos: u16,
-    done: bool,
-}
-
-impl<'a, T, A> Iterator for LRUCacheMutIterator<'a, T, A>
-where T: 'a,
-      A: 'a + Array<Item=Entry<T>>
-{
-    type Item = (CacheIndex, &'a mut T);
-
-    fn next(&mut self) -> Option<Self::Item> {
-        if self.done { return None }
-
-        // Use a raw pointer because the compiler doesn't know that subsequent calls can't alias.
-        let entry = unsafe {
-            &mut *(&mut self.cache.entries[self.pos as usize] as *mut Entry<T>)
-        };
-
-        let index = CacheIndex(self.pos);
-        if self.pos == self.cache.tail {
-            self.done = true;
-        }
-        self.pos = entry.next;
-
-        Some((index, &mut entry.val))
-    }
-}

components/style/Cargo.toml

@@ -45,7 +45,6 @@ html5ever = {version = "0.21", optional = true}
 itertools = "0.5"
 itoa = "0.3"
 lazy_static = "0.2"
-lru_cache = { path = "../lru_cache" }
 log = "0.3"
 malloc_size_of = { path = "../malloc_size_of" }
 malloc_size_of_derive = { path = "../malloc_size_of_derive" }
@@ -70,6 +69,7 @@ style_derive = {path = "../style_derive"}
 style_traits = {path = "../style_traits"}
 servo_url = {path = "../url", optional = true}
 time = "0.1"
+uluru = "0.1"
 unicode-bidi = "0.3"
 unicode-segmentation = "1.0"
 

components/style/context.rs

@@ -14,7 +14,6 @@ use euclid::ScaleFactor;
 use euclid::Size2D;
 use fnv::FnvHashMap;
 use font_metrics::FontMetricsProvider;
-use lru_cache::{Entry, LRUCache};
 #[cfg(feature = "gecko")] use gecko_bindings::structs;
 use parallel::{STACK_SAFETY_MARGIN_KB, STYLE_THREAD_STACK_SIZE_KB};
 #[cfg(feature = "servo")] use parking_lot::RwLock;
@@ -42,6 +41,7 @@ use time;
 use timer::Timer;
 use traversal::DomTraversal;
 use traversal_flags::TraversalFlags;
+use uluru::{Entry, LRUCache};
 
 pub use selectors::matching::QuirksMode;
 

components/style/lib.rs

@@ -57,7 +57,6 @@ extern crate itoa;
 extern crate lazy_static;
 #[macro_use]
 extern crate log;
-extern crate lru_cache;
 #[macro_use] extern crate malloc_size_of;
 #[macro_use] extern crate malloc_size_of_derive;
 #[allow(unused_extern_crates)]
@@ -86,6 +85,7 @@ extern crate style_derive;
 #[macro_use]
 extern crate style_traits;
 extern crate time;
+extern crate uluru;
 extern crate unicode_bidi;
 #[allow(unused_extern_crates)]
 extern crate unicode_segmentation;

components/style/sharing/mod.rs

@@ -70,7 +70,6 @@ use atomic_refcell::{AtomicRefCell, AtomicRefMut};
 use bloom::StyleBloom;
 use context::{SelectorFlagsMap, SharedStyleContext, StyleContext};
 use dom::{TElement, SendElement};
-use lru_cache::{LRUCache, Entry};
 use matching::MatchMethods;
 use owning_ref::OwningHandle;
 use properties::ComputedValues;
@@ -85,6 +84,7 @@ use std::mem;
 use std::ops::Deref;
 use style_resolver::{PrimaryStyle, ResolvedElementStyles};
 use stylist::Stylist;
+use uluru::{LRUCache, Entry};
 
 mod checks;