Move CSSStyleDeclaration.GetPropertyValue logic to style

components/script/dom/cssstyledeclaration.rs

@@ -104,55 +104,24 @@ impl CSSStyleDeclarationMethods for CSSStyleDeclaration {
 
     // https://dev.w3.org/csswg/cssom/#dom-cssstyledeclaration-getpropertyvalue
     fn GetPropertyValue(&self, mut property: DOMString) -> DOMString {
-        let owner = &self.owner;
-
-        // Step 1
-        property.make_ascii_lowercase();
-        let property = Atom::from(property);
-
         if self.readonly {
             // Readonly style declarations are used for getComputedStyle.
+            property.make_ascii_lowercase();
+            let property = Atom::from(property);
             return self.get_computed_style(&property).unwrap_or(DOMString::new());
         }
 
-        // Step 2
-        if let Some(shorthand) = Shorthand::from_name(&property) {
-            let style_attribute = owner.style_attribute().borrow();
+        let style_attribute = self.owner.style_attribute().borrow();
         let style_attribute = if let Some(ref style_attribute) = *style_attribute {
             style_attribute.read()
         } else {
-                // shorthand.longhands() is never empty, so with no style attribute
-                // step 2.2.2 would do this:
+            // No style attribute is like an empty style attribute: no matching declaration.
             return DOMString::new()
         };
 
-            // Step 2.1
-            let mut list = vec![];
-
-            // Step 2.2
-            for longhand in shorthand.longhands() {
-                // Step 2.2.1
-                let declaration = style_attribute.get(longhand);
-
-                // Step 2.2.2 & 2.2.3
-                match declaration {
-                    Some(&(ref declaration, _importance)) => list.push(declaration),
-                    None => return DOMString::new(),
-                }
-            }
-
-            // Step 2.3
-            // TODO: important is hardcoded to false because method does not implement it yet
-            let serialized_value = shorthand.serialize_shorthand_value_to_string(
-                list, Importance::Normal);
-            return DOMString::from(serialized_value);
-        }
-
-        // Step 3 & 4
-        owner.get_inline_style_declaration(&property, |d| match d {
-            Some(declaration) => DOMString::from(declaration.0.value()),
-            None => DOMString::new(),
-        })
+        let mut string = String::new();
+        style_attribute.property_value_to_css(&property, &mut string).unwrap();
+        DOMString::from(string)
     }
 
     // https://dev.w3.org/csswg/cssom/#dom-cssstyledeclaration-getpropertypriority

components/style/properties/declaration_block.rs

@@ -6,6 +6,7 @@ use cssparser::{DeclarationListParser, parse_important, ToCss};
 use cssparser::{Parser, AtRuleParser, DeclarationParser, Delimiter};
 use error_reporting::ParseErrorReporter;
 use parser::{ParserContext, ParserContextExtraData, log_css_error};
+use std::ascii::AsciiExt;
 use std::boxed::Box as StdBox;
 use std::fmt;
 use stylesheets::Origin;
@@ -66,16 +67,54 @@ impl PropertyDeclarationBlock {
     pub fn get(&self, property_name: &str) -> Option< &(PropertyDeclaration, Importance)> {
         self.declarations.iter().find(|&&(ref decl, _)| decl.matches(property_name))
     }
-}
 
-impl PropertyDeclarationBlock {
-    // Take a declaration block known to contain a single property,
-    // and serialize it
-    pub fn to_css_single_value<W>(&self, dest: &mut W, name: &str)
-        -> fmt::Result where W: fmt::Write {
+    /// Find the value of the given property in this block and serialize it
+    ///
+    /// https://dev.w3.org/csswg/cssom/#dom-cssstyledeclaration-getpropertyvalue
+    pub fn property_value_to_css<W>(&self, property_name: &str, dest: &mut W) -> fmt::Result
+    where W: fmt::Write {
+        // Step 1
+        let property = property_name.to_ascii_lowercase();
+
+        // Step 2
+        if let Some(shorthand) = Shorthand::from_name(&property) {
+            // Step 2.1
+            let mut list = Vec::new();
+
+            // Step 2.2
+            for longhand in shorthand.longhands() {
+                // Step 2.2.1
+                let declaration = self.get(longhand);
+
+                // Step 2.2.2 & 2.2.3
+                match declaration {
+                    Some(&(ref declaration, _importance)) => list.push(declaration),
+                    None => return Ok(()),
+                }
+            }
+
+            // Step 2.3
+            // TODO: importance is hardcoded because method does not implement it yet
+            let importance = Importance::Normal;
+            let appendable_value = shorthand.get_shorthand_appendable_value(list).unwrap();
+            return append_declaration_value(dest, appendable_value, importance)
+        }
+
+        if let Some(&(ref value, _importance)) = self.get(property_name) {
+            // Step 3
+            value.to_css(dest)
+        } else {
+            // Step 4
+            Ok(())
+        }
+    }
+
+    /// Take a declaration block known to contain a single property and serialize it.
+    pub fn single_value_to_css<W>(&self, property_name: &str, dest: &mut W) -> fmt::Result
+    where W: fmt::Write {
         match self.declarations.len() {
             0 => Err(fmt::Error),
-            1 if self.declarations[0].0.name().eq_str_ignore_ascii_case(name) => {
+            1 if self.declarations[0].0.name().eq_str_ignore_ascii_case(property_name) => {
                 self.declarations[0].0.to_css(dest)
             }
             _ => {
@@ -84,7 +123,7 @@ impl PropertyDeclarationBlock {
                     -> &PropertyDeclaration {
                     &dec.0
                 }
-                let shorthand = try!(Shorthand::from_name(name).ok_or(fmt::Error));
+                let shorthand = try!(Shorthand::from_name(property_name).ok_or(fmt::Error));
                 if !self.declarations.iter().all(|decl| decl.0.shorthands().contains(&shorthand)) {
                     return Err(fmt::Error)
                 }

components/style/properties/properties.mako.rs

@@ -410,15 +410,6 @@ impl Shorthand {
         }
     }
 
-    /// Serializes possible shorthand value to String.
-    pub fn serialize_shorthand_value_to_string<'a, I>(self, declarations: I, importance: Importance) -> String
-    where I: IntoIterator<Item=&'a PropertyDeclaration>, I::IntoIter: Clone {
-        let appendable_value = self.get_shorthand_appendable_value(declarations).unwrap();
-        let mut result = String::new();
-        append_declaration_value(&mut result, appendable_value, importance).unwrap();
-        result
-    }
-
     /// Serializes possible shorthand name with value to input buffer given a list of longhand declarations.
     /// On success, returns true if shorthand value is written and false if no shorthand value is present.
     pub fn serialize_shorthand_to_buffer<'a, W, I>(self,