diff --git a/components/style/restyle_hints.rs b/components/style/restyle_hints.rs
index ba69870d53a..2d5d9aed27c 100644
--- a/components/style/restyle_hints.rs
+++ b/components/style/restyle_hints.rs
@@ -16,7 +16,7 @@ use element_state::*;
 use gecko_bindings::structs::nsRestyleHint;
 #[cfg(feature = "servo")]
 use heapsize::HeapSizeOf;
-use selector_map::SelectorMap;
+use selector_map::{SelectorMap, SelectorMapEntry};
 use selector_parser::{NonTSPseudoClass, PseudoElement, SelectorImpl, Snapshot, SnapshotMap, AttrValue};
 use selectors::Element;
 use selectors::attr::{AttrSelectorOperation, NamespaceConstraint};
@@ -25,7 +25,6 @@ use selectors::matching::matches_selector;
 use selectors::parser::{Combinator, Component, Selector, SelectorInner, SelectorMethods};
 use selectors::visitor::SelectorVisitor;
 use smallvec::SmallVec;
-use std::borrow::Borrow;
 use std::cell::Cell;
 use std::clone::Clone;
 use std::cmp;
@@ -759,8 +758,8 @@ pub struct Dependency {
     pub sensitivities: Sensitivities,
 }
 
-impl Borrow<SelectorInner<SelectorImpl>> for Dependency {
-    fn borrow(&self) -> &SelectorInner<SelectorImpl> {
+impl SelectorMapEntry for Dependency {
+    fn selector(&self) -> &SelectorInner<SelectorImpl> {
         &self.selector
     }
 }
diff --git a/components/style/selector_map.rs b/components/style/selector_map.rs
index 47a236f3d88..497baf2f914 100644
--- a/components/style/selector_map.rs
+++ b/components/style/selector_map.rs
@@ -20,6 +20,18 @@ use std::collections::HashMap;
 use std::hash::Hash;
 use stylist::{ApplicableDeclarationBlock, Rule};
 
+/// A trait to abstract over a given selector map entry.
+pub trait SelectorMapEntry : Sized + Clone {
+    /// Get the selector we should use to index in the selector map.
+    fn selector(&self) -> &SelectorInner<SelectorImpl>;
+}
+
+impl SelectorMapEntry for SelectorInner<SelectorImpl> {
+    fn selector(&self) -> &SelectorInner<SelectorImpl> {
+        self
+    }
+}
+
 /// Map element data to selector-providing objects for which the last simple
 /// selector starts with them.
 ///
@@ -44,7 +56,7 @@ use stylist::{ApplicableDeclarationBlock, Rule};
 /// TODO: Tune the initial capacity of the HashMap
 #[derive(Debug)]
 #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
-pub struct SelectorMap<T: Clone + Borrow<SelectorInner<SelectorImpl>>> {
+pub struct SelectorMap<T: SelectorMapEntry> {
     /// A hash from an ID to rules which contain that ID selector.
     pub id_hash: FnvHashMap<Atom, Vec<T>>,
     /// A hash from a class name to rules which contain that class selector.
@@ -62,7 +74,7 @@ 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> where T: Clone + Borrow<SelectorInner<SelectorImpl>> {
+impl<T: SelectorMapEntry> SelectorMap<T> {
     /// Trivially constructs an empty `SelectorMap`.
     pub fn new() -> Self {
         SelectorMap {
@@ -217,22 +229,22 @@ impl SelectorMap<Rule> {
     }
 }
 
-impl<T> SelectorMap<T> where T: Clone + Borrow<SelectorInner<SelectorImpl>> {
+impl<T: SelectorMapEntry> SelectorMap<T> {
     /// Inserts into the correct hash, trying id, class, and localname.
     pub fn insert(&mut self, entry: T) {
         self.count += 1;
 
-        if let Some(id_name) = get_id_name(entry.borrow()) {
+        if let Some(id_name) = get_id_name(entry.selector()) {
             find_push(&mut self.id_hash, id_name, entry);
             return;
         }
 
-        if let Some(class_name) = get_class_name(entry.borrow()) {
+        if let Some(class_name) = get_class_name(entry.selector()) {
             find_push(&mut self.class_hash, class_name, entry);
             return;
         }
 
-        if let Some(LocalNameSelector { name, lower_name }) = get_local_name(entry.borrow()) {
+        if let Some(LocalNameSelector { name, lower_name }) = get_local_name(entry.selector()) {
             // If the local name in the selector isn't lowercase, insert it into
             // the rule hash twice. This means that, during lookup, we can always
             // find the rules based on the local name of the element, regardless
diff --git a/components/style/stylist.rs b/components/style/stylist.rs
index 9fd06ee16c5..7fb64c8acf5 100644
--- a/components/style/stylist.rs
+++ b/components/style/stylist.rs
@@ -22,7 +22,7 @@ use properties::INHERIT_ALL;
 use properties::PropertyDeclarationBlock;
 use restyle_hints::{HintComputationContext, DependencySet, RestyleHint};
 use rule_tree::{CascadeLevel, RuleTree, StrongRuleNode, StyleSource};
-use selector_map::SelectorMap;
+use selector_map::{SelectorMap, SelectorMapEntry};
 use selector_parser::{SelectorImpl, PseudoElement};
 use selectors::attr::NamespaceConstraint;
 use selectors::bloom::BloomFilter;
@@ -33,7 +33,6 @@ use selectors::visitor::SelectorVisitor;
 use shared_lock::{Locked, SharedRwLockReadGuard, StylesheetGuards};
 use sink::Push;
 use smallvec::{SmallVec, VecLike};
-use std::borrow::Borrow;
 #[cfg(feature = "servo")]
 use std::marker::PhantomData;
 use style_traits::viewport::ViewportConstraints;
@@ -1252,8 +1251,8 @@ pub struct Rule {
     pub source_order: usize,
 }
 
-impl Borrow<SelectorInner<SelectorImpl>> for Rule {
-    fn borrow(&self) -> &SelectorInner<SelectorImpl> {
+impl SelectorMapEntry for Rule {
+    fn selector(&self) -> &SelectorInner<SelectorImpl> {
         &self.selector.inner
     }
 }