Create and utilize utility for joining strs

3 files changed, 12 insertions, 12 deletions

diff --git a/components/script/dom/attr.rs b/components/script/dom/attr.rs
index a8f4b897f15..782ab3fd884 100644
--- a/components/script/dom/attr.rs
+++ b/components/script/dom/attr.rs
@@ -14,7 +14,7 @@ use dom::window::Window;
 use dom::virtualmethods::vtable_for;
 
 use devtools_traits::AttrInfo;
-use util::str::{DOMString, parse_unsigned_integer, split_html_space_chars};
+use util::str::{DOMString, parse_unsigned_integer, split_html_space_chars, str_join};
 
 use string_cache::{Atom, Namespace};
 
@@ -49,11 +49,7 @@ impl AttrValue {
     }
 
     pub fn from_atomic_tokens(atoms: Vec<Atom>) -> AttrValue {
-        let tokens = atoms.iter().fold(String::new(), |mut s, atom| {
-            if !s.is_empty() { s.push('\x20'); }
-            s.push_str(atom);
-            s
-        });
+        let tokens = str_join(&atoms, "\x20");
         AttrValue::TokenList(tokens, atoms)
     }
 
diff --git a/components/script/dom/domtokenlist.rs b/components/script/dom/domtokenlist.rs
index f863996e9ca..f7a02cdf572 100644
--- a/components/script/dom/domtokenlist.rs
+++ b/components/script/dom/domtokenlist.rs
@@ -13,7 +13,7 @@ use dom::bindings::utils::{Reflector, reflect_dom_object};
 use dom::element::{Element, AttributeHandlers};
 use dom::node::window_from_node;
 
-use util::str::{DOMString, HTML_SPACE_CHARACTERS};
+use util::str::{DOMString, HTML_SPACE_CHARACTERS, str_join};
 use string_cache::Atom;
 
 use std::borrow::ToOwned;
@@ -158,10 +158,6 @@ impl<'a> DOMTokenListMethods for &'a DOMTokenList {
     // https://dom.spec.whatwg.org/#stringification-behavior
     fn Stringifier(self) -> DOMString {
         let tokenlist = self.element.root().r().get_tokenlist_attribute(&self.local_name);
-        tokenlist.iter().fold(String::new(), |mut s, atom| {
-            if !s.is_empty() { s.push('\x20'); }
-            s.push_str(atom);
-            s
-        })
+        str_join(&tokenlist, "\x20")
     }
 }
diff --git a/components/util/str.rs b/components/util/str.rs
index b82f46598b7..fe6127e1106 100644
--- a/components/util/str.rs
+++ b/components/util/str.rs
@@ -327,3 +327,11 @@ impl Deref for LowercaseString {
 pub unsafe fn c_str_to_string(s: *const c_char) -> String {
     from_utf8(CStr::from_ptr(s).to_bytes()).unwrap().to_owned()
 }
+
+pub fn str_join<T: AsRef<str>>(strs: &[T], join: &str) -> String {
+    strs.iter().fold(String::new(), |mut acc, s| {
+        if !acc.is_empty() { acc.push_str(join); }
+        acc.push_str(s.as_ref());
+        acc
+    })
+}