Implement document.lastModified (fixes #2972, #3127).

src/components/script/dom/document.rs

@@ -59,6 +59,7 @@ use std::collections::hashmap::HashMap;
 use std::ascii::StrAsciiExt;
 use std::cell::{Cell, RefCell};
 use url::Url;
+use time;
 
 #[deriving(PartialEq,Encodable)]
 pub enum IsHTMLDocument {
@@ -74,6 +75,7 @@ pub struct Document {
     idmap: Traceable<RefCell<HashMap<DOMString, Vec<JS<Element>>>>>,
     implementation: Cell<Option<JS<DOMImplementation>>>,
     content_type: DOMString,
+    last_modified: Traceable<RefCell<Option<DOMString>>>,
     pub encoding_name: Traceable<RefCell<DOMString>>,
     pub is_html_document: bool,
     url: Untraceable<Url>,
@@ -146,6 +148,7 @@ pub trait DocumentHelpers {
     fn url<'a>(&'a self) -> &'a Url;
     fn quirks_mode(&self) -> QuirksMode;
     fn set_quirks_mode(&self, mode: QuirksMode);
+    fn set_last_modified(&self, value: DOMString);
     fn set_encoding_name(&self, name: DOMString);
     fn content_changed(&self);
     fn damage_and_reflow(&self, damage: DocumentDamageLevel);
@@ -168,6 +171,10 @@ impl<'a> DocumentHelpers for JSRef<'a, Document> {
         self.quirks_mode.deref().set(mode);
     }
 
+    fn set_last_modified(&self, value: DOMString) {
+        *self.last_modified.deref().borrow_mut() = Some(value);
+    }
+
     fn set_encoding_name(&self, name: DOMString) {
         *self.encoding_name.deref().borrow_mut() = name;
     }
@@ -278,6 +285,7 @@ impl Document {
                     NonHTMLDocument => "application/xml".to_string()
                 }
             },
+            last_modified: Traceable::new(RefCell::new(None)),
             url: Untraceable::new(url),
             // http://dom.spec.whatwg.org/#concept-document-quirks
             quirks_mode: Untraceable::new(Cell::new(NoQuirks)),
@@ -569,6 +577,14 @@ impl<'a> DocumentMethods for JSRef<'a, Document> {
         }
     }
 
+    // http://www.whatwg.org/html/#dom-document-lastmodified
+    fn LastModified(&self) -> DOMString {
+        match *self.last_modified.borrow() {
+            Some(ref t) => t.clone(),
+            None => time::now().strftime("%m/%d/%Y %H:%M:%S"),
+        }
+    }
+
     // http://dom.spec.whatwg.org/#dom-document-createrange
     fn CreateRange(&self) -> Temporary<Range> {
         Range::new(self)

src/components/script/dom/webidls/Document.webidl

@@ -49,6 +49,7 @@ interface Document : Node {
 
 /* http://www.whatwg.org/specs/web-apps/current-work/#the-document-object */
 partial interface Document {
+  readonly attribute DOMString lastModified;
            [SetterThrows]
            attribute DOMString title;
            [SetterThrows]

src/components/script/html/hubbub_html_parser.rs

@@ -33,6 +33,8 @@ use std::cell::RefCell;
 use std::comm::{channel, Sender, Receiver};
 use style::Stylesheet;
 use url::{Url, UrlParser};
+use http::headers::HeaderEnum;
+use time;
 
 macro_rules! handle_element(
     ($document: expr,
@@ -158,6 +160,30 @@ fn js_script_listener(to_parent: Sender<HtmlDiscoveryMessage>,
     assert!(to_parent.send_opt(HtmlDiscoveredScript(result_vec)).is_ok());
 }
 
+// Parses an RFC 2616 compliant date/time string, and returns a localized
+// date/time string in a format suitable for document.lastModified.
+fn parse_last_modified(timestamp: &str) -> String {
+    let format = "%m/%d/%Y %H:%M:%S";
+
+    // RFC 822, updated by RFC 1123
+    match time::strptime(timestamp, "%a, %d %b %Y %T %Z") {
+        Ok(t) => return t.to_local().strftime(format),
+        Err(_) => ()
+    }
+
+    // RFC 850, obsoleted by RFC 1036
+    match time::strptime(timestamp, "%A, %d-%b-%y %T %Z") {
+        Ok(t) => return t.to_local().strftime(format),
+        Err(_) => ()
+    }
+
+    // ANSI C's asctime() format
+    match time::strptime(timestamp, "%c") {
+        Ok(t) => t.to_local().strftime(format),
+        Err(_) => String::from_str("")
+    }
+}
+
 // Silly macros to handle constructing      DOM nodes. This produces bad code and should be optimized
 // via atomization (issue #85).
 
@@ -323,6 +349,18 @@ pub fn parse_html(page: &Page,
 
     debug!("Fetched page; metadata is {:?}", load_response.metadata);
 
+    load_response.metadata.headers.map(|headers| {
+        let header = headers.iter().find(|h|
+            h.header_name().as_slice().to_ascii_lower() == "last-modified".to_string()
+        );
+
+        match header {
+            Some(h) => document.set_last_modified(
+                parse_last_modified(h.header_value().as_slice())),
+            None => {},
+        };
+    });
+
     let base_url = &load_response.metadata.final_url;
 
     {