Auto merge of #12311 - Ms2ger:cache, r=nox

Move the cache module out of util.

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13 files changed, 16 insertions, 81 deletions

diff --git a/components/gfx/font.rs b/components/gfx/font.rs
index c401c616d8f..e92fff1c58f 100644
--- a/components/gfx/font.rs
+++ b/components/gfx/font.rs
@@ -12,6 +12,7 @@ use smallvec::SmallVec;
 use std::ascii::AsciiExt;
 use std::borrow::ToOwned;
 use std::cell::RefCell;
+use std::collections::HashMap;
 use std::rc::Rc;
 use std::str;
 use std::sync::Arc;
@@ -22,7 +23,6 @@ use text::glyph::{ByteIndex, GlyphData, GlyphId, GlyphStore};
 use text::shaping::ShaperMethods;
 use time;
 use unicode_script::Script;
-use util::cache::HashCache;
 use webrender_traits;
 
 macro_rules! ot_tag {
@@ -109,8 +109,8 @@ pub struct Font {
     pub requested_pt_size: Au,
     pub actual_pt_size: Au,
     shaper: Option<Shaper>,
-    shape_cache: RefCell<HashCache<ShapeCacheEntry, Arc<GlyphStore>>>,
-    glyph_advance_cache: RefCell<HashCache<u32, FractionalPixel>>,
+    shape_cache: RefCell<HashMap<ShapeCacheEntry, Arc<GlyphStore>>>,
+    glyph_advance_cache: RefCell<HashMap<u32, FractionalPixel>>,
     pub font_key: Option<webrender_traits::FontKey>,
 }
 
@@ -130,8 +130,8 @@ impl Font {
             requested_pt_size: requested_pt_size,
             actual_pt_size: actual_pt_size,
             metrics: metrics,
-            shape_cache: RefCell::new(HashCache::new()),
-            glyph_advance_cache: RefCell::new(HashCache::new()),
+            shape_cache: RefCell::new(HashMap::new()),
+            glyph_advance_cache: RefCell::new(HashMap::new()),
             font_key: font_key,
         }
     }
@@ -180,7 +180,7 @@ impl Font {
             text: text.to_owned(),
             options: *options,
         };
-        let result = self.shape_cache.borrow_mut().find_or_create(lookup_key, || {
+        let result = self.shape_cache.borrow_mut().entry(lookup_key).or_insert_with(|| {
             let start_time = time::precise_time_ns();
             let mut glyphs = GlyphStore::new(text.len(),
                                              options.flags.contains(IS_WHITESPACE_SHAPING_FLAG),
@@ -201,7 +201,7 @@ impl Font {
             TEXT_SHAPING_PERFORMANCE_COUNTER.fetch_add((end_time - start_time) as usize,
                                                        Ordering::Relaxed);
             Arc::new(glyphs)
-        });
+        }).clone();
         self.shaper = shaper;
         result
     }
@@ -269,7 +269,7 @@ impl Font {
     }
 
     pub fn glyph_h_advance(&self, glyph: GlyphId) -> FractionalPixel {
-        self.glyph_advance_cache.borrow_mut().find_or_create(glyph, || {
+        *self.glyph_advance_cache.borrow_mut().entry(glyph).or_insert_with(|| {
             match self.handle.glyph_h_advance(glyph) {
                 Some(adv) => adv,
                 None => 10f64 as FractionalPixel // FIXME: Need fallback strategy
diff --git a/components/servo/Cargo.lock b/components/servo/Cargo.lock
index 5f6e0da6de8..5f2d29cee62 100644
--- a/components/servo/Cargo.lock
+++ b/components/servo/Cargo.lock
@@ -2466,7 +2466,6 @@ dependencies = [
  "lazy_static 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "num_cpus 0.2.13 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand 0.3.14 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.19 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.7.11 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.7.11 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/components/style/animation.rs b/components/style/animation.rs
index 1f0cbcaefde..9d8b88f0c1f 100644
--- a/components/style/animation.rs
+++ b/components/style/animation.rs
@@ -498,7 +498,7 @@ where Impl: SelectorImplExt,
     debug!("update_style_for_animation: entering");
     debug_assert!(!animation.is_expired());
     match *animation {
-        Animation::Transition(_, start_time, ref frame, expired) => {
+        Animation::Transition(_, start_time, ref frame, _) => {
             debug!("update_style_for_animation: transition found");
             let now = time::precise_time_s();
             let mut new_style = (*style).clone();
diff --git a/components/util/cache.rs b/components/style/cache.rs
index f446f43b498..e15c99eea2c 100644
--- a/components/util/cache.rs
+++ b/components/style/cache.rs
@@ -2,60 +2,13 @@
  * 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/. */
 
+//! Two simple cache data structures.
+
 use rand;
 use rand::Rng;
-use std::collections::HashMap;
-use std::collections::hash_map::Entry::{Occupied, Vacant};
-use std::default::Default;
-use std::hash::{BuildHasherDefault, Hash, Hasher, SipHasher};
+use std::hash::{Hash, Hasher, SipHasher};
 use std::slice::Iter;
 
-
-#[derive(Debug)]
-pub struct HashCache<K, V>
-    where K: PartialEq + Eq + Hash,
-          V: Clone,
-{
-    entries: HashMap<K, V, BuildHasherDefault<SipHasher>>,
-}
-
-impl<K, V> HashCache<K, V>
-    where K: PartialEq + Eq + Hash,
-          V: Clone,
-{
-    pub fn new() -> HashCache<K, V> {
-        HashCache {
-          entries: HashMap::with_hasher(Default::default()),
-        }
-    }
-
-    pub fn insert(&mut self, key: K, value: V) {
-        self.entries.insert(key, value);
-    }
-
-    pub fn find(&self, key: &K) -> Option<V> {
-        match self.entries.get(key) {
-            Some(v) => Some(v.clone()),
-            None => None,
-        }
-    }
-
-    pub fn find_or_create<F>(&mut self, key: K, mut blk: F) -> V where F: FnMut() -> V {
-        match self.entries.entry(key) {
-            Occupied(occupied) => {
-                (*occupied.get()).clone()
-            }
-            Vacant(vacant) => {
-                (*vacant.insert(blk())).clone()
-            }
-        }
-    }
-
-    pub fn evict_all(&mut self) {
-        self.entries.clear();
-    }
-}
-
 pub struct LRUCache<K, V> {
     entries: Vec<(K, V)>,
     cache_size: usize,
diff --git a/components/style/lib.rs b/components/style/lib.rs
index 6e45d9a9411..7fe5fe1bcca 100644
--- a/components/style/lib.rs
+++ b/components/style/lib.rs
@@ -72,6 +72,7 @@ extern crate util;
 pub mod animation;
 pub mod attr;
 pub mod bezier;
+pub mod cache;
 pub mod context;
 pub mod custom_properties;
 pub mod data;
diff --git a/components/style/matching.rs b/components/style/matching.rs
index 5d4fa82b8ce..8b843844fbc 100644
--- a/components/style/matching.rs
+++ b/components/style/matching.rs
@@ -7,6 +7,7 @@
 #![allow(unsafe_code)]
 
 use animation::{self, Animation};
+use cache::{LRUCache, SimpleHashCache};
 use context::{StyleContext, SharedStyleContext};
 use data::PrivateStyleData;
 use dom::{TElement, TNode, TRestyleDamage};
@@ -25,7 +26,6 @@ use std::slice::Iter;
 use std::sync::Arc;
 use string_cache::{Atom, Namespace};
 use util::arc_ptr_eq;
-use util::cache::{LRUCache, SimpleHashCache};
 use util::opts;
 
 fn create_common_style_affecting_attributes_from_element<E: TElement>(element: &E)
diff --git a/components/util/Cargo.toml b/components/util/Cargo.toml
index f5c87179cfc..3a9478a49b3 100644
--- a/components/util/Cargo.toml
+++ b/components/util/Cargo.toml
@@ -24,7 +24,6 @@ ipc-channel = {git = "https://github.com/servo/ipc-channel", optional = true}
 lazy_static = "0.2"
 log = "0.3.5"
 num_cpus = "0.2.2"
-rand = "0.3"
 rustc-serialize = "0.3"
 serde = {version = "0.7.11", optional = true}
 serde_macros = {version = "0.7.11", optional = true}
diff --git a/components/util/lib.rs b/components/util/lib.rs
index 6ffa4a4a2b5..bcad9ea3705 100644
--- a/components/util/lib.rs
+++ b/components/util/lib.rs
@@ -20,7 +20,6 @@ extern crate getopts;
 #[allow(unused_extern_crates)] #[macro_use] extern crate lazy_static;
 #[macro_use] extern crate log;
 extern crate num_cpus;
-extern crate rand;
 extern crate rustc_serialize;
 #[cfg(feature = "servo")] extern crate serde;
 extern crate url;
@@ -30,7 +29,6 @@ extern crate xdg;
 use std::sync::Arc;
 
 pub mod basedir;
-pub mod cache;
 pub mod geometry;
 #[cfg(feature = "servo")] #[allow(unsafe_code)] pub mod ipc;
 #[allow(unsafe_code)] pub mod opts;
diff --git a/ports/cef/Cargo.lock b/ports/cef/Cargo.lock
index 471c3a6eb6d..b8258ccb8df 100644
--- a/ports/cef/Cargo.lock
+++ b/ports/cef/Cargo.lock
@@ -2335,7 +2335,6 @@ dependencies = [
  "lazy_static 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "num_cpus 0.2.13 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand 0.3.14 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.19 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.7.11 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.7.11 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/ports/geckolib/Cargo.lock b/ports/geckolib/Cargo.lock
index 1bb5d71923d..bec14181271 100644
--- a/ports/geckolib/Cargo.lock
+++ b/ports/geckolib/Cargo.lock
@@ -573,7 +573,6 @@ dependencies = [
  "lazy_static 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "num_cpus 0.2.13 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand 0.3.14 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.19 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.7.11 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.7.11 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/tests/unit/util/cache.rs b/tests/unit/style/cache.rs
index 9bb207622bd..7456a87b55c 100644
--- a/tests/unit/util/cache.rs
+++ b/tests/unit/style/cache.rs
@@ -3,20 +3,7 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 use std::cell::Cell;
-use util::cache::{HashCache, LRUCache};
-
-#[test]
-fn test_hashcache() {
-    let mut cache: HashCache<usize, Cell<&str>> = HashCache::new();
-
-    cache.insert(1, Cell::new("one"));
-    assert!(cache.find(&1).is_some());
-    assert!(cache.find(&2).is_none());
-
-    cache.find_or_create(2, || { Cell::new("two") });
-    assert!(cache.find(&1).is_some());
-    assert!(cache.find(&2).is_some());
-}
+use style::cache::LRUCache;
 
 #[test]
 fn test_lru_cache() {
diff --git a/tests/unit/style/lib.rs b/tests/unit/style/lib.rs
index fd725d79635..803dd7ce05e 100644
--- a/tests/unit/style/lib.rs
+++ b/tests/unit/style/lib.rs
@@ -18,6 +18,7 @@ extern crate url;
 extern crate util;
 
 mod attr;
+mod cache;
 mod logical_geometry;
 mod media_queries;
 mod properties;
diff --git a/tests/unit/util/lib.rs b/tests/unit/util/lib.rs
index af5de45579d..1ad4e55d965 100644
--- a/tests/unit/util/lib.rs
+++ b/tests/unit/util/lib.rs
@@ -6,7 +6,6 @@
 
 extern crate util;
 
-mod cache;
 mod opts;
 mod prefs;
 mod thread;