Auto merge of #18334 - Manishearth:hashglobe, r=emilio,Gankro

Add fallible hashmaps from HashGlobe for stylo

HashGlobe code is r=emilio,Gankro

integration code is r=emilio from https://bugzilla.mozilla.org/show_bug.cgi?id=1393656

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components/style/Cargo.toml

@@ -41,6 +41,7 @@ cssparser = "0.19.5"
 encoding = {version = "0.2", optional = true}
 euclid = "0.15"
 fnv = "1.0"
+hashglobe = { path = "../hashglobe" }
 heapsize = {version = "0.4", optional = true}
 heapsize_derive = {version = "0.1", optional = true}
 itertools = "0.5"

components/style/custom_properties.rs

@@ -8,13 +8,13 @@
 
 use Atom;
 use cssparser::{Delimiter, Parser, ParserInput, SourcePosition, Token, TokenSerializationType};
+use hash::{HashMap, HashSet};
 use parser::ParserContext;
 use properties::{CSSWideKeyword, DeclaredValue};
 use selectors::parser::SelectorParseError;
 use servo_arc::Arc;
 use std::ascii::AsciiExt;
 use std::borrow::{Borrow, Cow};
-use std::collections::{HashMap, HashSet};
 use std::fmt;
 use std::hash::Hash;
 use style_traits::{ToCss, StyleParseError, ParseError};

components/style/dom.rs

@@ -28,7 +28,7 @@ use servo_arc::{Arc, ArcBorrow};
 use shared_lock::Locked;
 use smallvec::VecLike;
 use std::fmt;
-#[cfg(feature = "gecko")] use std::collections::HashMap;
+#[cfg(feature = "gecko")] use hash::HashMap;
 use std::fmt::Debug;
 use std::hash::Hash;
 use std::ops::Deref;

components/style/gecko/wrapper.rs

@@ -66,6 +66,7 @@ use gecko_bindings::structs::nsChangeHint;
 use gecko_bindings::structs::nsIDocument_DocumentTheme as DocumentTheme;
 use gecko_bindings::structs::nsRestyleHint;
 use gecko_bindings::sugar::ownership::{HasArcFFI, HasSimpleFFI};
+use hash::HashMap;
 use logical_geometry::WritingMode;
 use media_queries::Device;
 use properties::{ComputedValues, parse_style_attribute};
@@ -83,7 +84,6 @@ use selectors::sink::Push;
 use servo_arc::{Arc, ArcBorrow, RawOffsetArc};
 use shared_lock::Locked;
 use std::cell::RefCell;
-use std::collections::HashMap;
 use std::fmt;
 use std::hash::{Hash, Hasher};
 use std::mem;
@@ -1361,7 +1361,7 @@ impl<'le> TElement for GeckoElement<'le> {
                                 after_change_style: &ComputedValues)
                                 -> bool {
         use gecko_bindings::structs::nsCSSPropertyID;
-        use std::collections::HashSet;
+        use hash::HashSet;
 
         debug_assert!(self.might_need_transitions_update(Some(before_change_style),
                                                          after_change_style),

components/style/hash.rs

@@ -0,0 +1,32 @@
+/* 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/. */
+
+//! Reexports of hashglobe types in Gecko mode, and stdlib hashmap shims in Servo mode
+//!
+//! Can go away when the stdlib gets fallible collections
+//! https://github.com/rust-lang/rfcs/pull/2116
+
+use fnv;
+
+#[cfg(feature = "gecko")]
+pub use hashglobe::hash_map::HashMap;
+#[cfg(feature = "gecko")]
+pub use hashglobe::hash_set::HashSet;
+
+
+#[cfg(feature = "servo")]
+pub use hashglobe::fake::{HashMap, HashSet};
+
+/// Appropriate reexports of hash_map types
+pub mod map {
+    #[cfg(feature = "gecko")]
+    pub use hashglobe::hash_map::{Entry, Iter};
+    #[cfg(feature = "servo")]
+    pub use std::collections::hash_map::{Entry, Iter};
+}
+
+/// Hash map that uses the FNV hasher
+pub type FnvHashMap<K, V> = HashMap<K, V, fnv::FnvBuildHasher>;
+/// Hash set that uses the FNV hasher
+pub type FnvHashSet<T> = HashSet<T, fnv::FnvBuildHasher>;

components/style/lib.rs

@@ -49,6 +49,7 @@ extern crate bitflags;
 extern crate euclid;
 extern crate fnv;
 #[cfg(feature = "gecko")] #[macro_use] pub mod gecko_string_cache;
+extern crate hashglobe;
 #[cfg(feature = "servo")] extern crate heapsize;
 #[cfg(feature = "servo")] #[macro_use] extern crate heapsize_derive;
 extern crate itertools;
@@ -112,6 +113,7 @@ pub mod font_face;
 pub mod font_metrics;
 #[cfg(feature = "gecko")] #[allow(unsafe_code)] pub mod gecko;
 #[cfg(feature = "gecko")] #[allow(unsafe_code)] pub mod gecko_bindings;
+pub mod hash;
 pub mod invalidation;
 #[allow(missing_docs)] // TODO.
 pub mod logical_geometry;

components/style/properties/helpers/animated_properties.mako.rs

@@ -31,7 +31,7 @@ use selectors::parser::SelectorParseError;
 use smallvec::SmallVec;
 use std::borrow::Cow;
 use std::cmp;
-#[cfg(feature = "gecko")] use fnv::FnvHashMap;
+#[cfg(feature = "gecko")] use hash::FnvHashMap;
 use style_traits::ParseError;
 use super::ComputedValues;
 #[cfg(feature = "gecko")]

components/style/properties/longhand/position.mako.rs

@@ -416,7 +416,7 @@ ${helpers.predefined_type("object-position",
         products="gecko"
         animation_value_type="discrete"
         boxed="True">
-    use std::collections::HashMap;
+    use hash::HashMap;
     use std::fmt;
     use std::ops::Range;
     use str::HTML_SPACE_CHARACTERS;

components/style/properties/properties.mako.rs

@@ -13,7 +13,7 @@
 #[cfg(feature = "servo")] use app_units::Au;
 use servo_arc::{Arc, UniqueArc};
 use std::borrow::Cow;
-use std::collections::HashSet;
+use hash::HashSet;
 use std::{fmt, mem, ops};
 #[cfg(feature = "gecko")] use std::ptr;
 

components/style/rule_tree/mod.rs

@@ -1007,7 +1007,7 @@ impl StrongRuleNode {
 
     unsafe fn assert_free_list_has_no_duplicates_or_null(&self) {
         assert!(cfg!(debug_assertions), "This is an expensive check!");
-        use std::collections::HashSet;
+        use hash::HashSet;
 
         let me = &*self.ptr();
         assert!(me.is_root());

components/style/selector_map.rs

@@ -9,6 +9,8 @@ use {Atom, LocalName};
 use applicable_declarations::ApplicableDeclarationBlock;
 use context::QuirksMode;
 use dom::TElement;
+use hash::{HashMap, HashSet};
+use hash::map as hash_map;
 use pdqsort::sort_by;
 use precomputed_hash::PrecomputedHash;
 use rule_tree::CascadeLevel;
@@ -16,8 +18,6 @@ use selector_parser::SelectorImpl;
 use selectors::matching::{matches_selector, MatchingContext, ElementSelectorFlags};
 use selectors::parser::{Component, Combinator, SelectorIter};
 use smallvec::{SmallVec, VecLike};
-use std::collections::{HashMap, HashSet};
-use std::collections::hash_map;
 use std::hash::{BuildHasherDefault, Hash, Hasher};
 use stylist::Rule;
 
@@ -93,7 +93,7 @@ pub trait SelectorMapEntry : Sized + Clone {
 /// TODO: Tune the initial capacity of the HashMap
 #[derive(Debug)]
 #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
-pub struct SelectorMap<T> {
+pub struct SelectorMap<T: 'static> {
     /// A hash from an ID to rules which contain that ID selector.
     pub id_hash: MaybeCaseInsensitiveHashMap<Atom, SmallVec<[T; 1]>>,
     /// A hash from a class name to rules which contain that class selector.
@@ -111,7 +111,10 @@ fn sort_by_key<T, F: Fn(&T) -> K, K: Ord>(v: &mut [T], f: F) {
     sort_by(v, |a, b| f(a).cmp(&f(b)))
 }
 
-impl<T> SelectorMap<T> {
+// FIXME(Manishearth) the 'static bound can be removed when
+// our HashMap fork (hashglobe) is able to use NonZero,
+// or when stdlib gets fallible collections
+impl<T: 'static> SelectorMap<T> {
     /// Trivially constructs an empty `SelectorMap`.
     pub fn new() -> Self {
         SelectorMap {
@@ -461,9 +464,12 @@ fn find_push<Str: Eq + Hash, V, VL>(map: &mut PrecomputedHashMap<Str, VL>,
 /// Wrapper for PrecomputedHashMap that does ASCII-case-insensitive lookup in quirks mode.
 #[derive(Debug)]
 #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
-pub struct MaybeCaseInsensitiveHashMap<K: PrecomputedHash + Hash + Eq, V>(PrecomputedHashMap<K, V>);
+pub struct MaybeCaseInsensitiveHashMap<K: PrecomputedHash + Hash + Eq, V: 'static>(PrecomputedHashMap<K, V>);
 
-impl<V> MaybeCaseInsensitiveHashMap<Atom, V> {
+// FIXME(Manishearth) the 'static bound can be removed when
+// our HashMap fork (hashglobe) is able to use NonZero,
+// or when stdlib gets fallible collections
+impl<V: 'static> MaybeCaseInsensitiveHashMap<Atom, V> {
     /// Empty map
     pub fn new() -> Self {
         MaybeCaseInsensitiveHashMap(PrecomputedHashMap::default())