Auto merge of #6741 - servo:fix-setpropertypriority, r=pcwalton

Fix CSSStyleDeclaration::setPropertyPriority and some refactoring

r? @Ms2ger

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components/style/build.rs

@@ -5,12 +5,12 @@
 use std::env;
 use std::fs::File;
 use std::io::Write;
-use std::process::{Command, Stdio};
+use std::process::{Command, Stdio, exit};
 use std::path::Path;
 
 
 fn main() {
-    let python = if Command::new("python2.7").arg("--version").status().unwrap().success() {
+    let python = if Command::new("python2.7").arg("--version").output().unwrap().status.success() {
         "python2.7"
     } else {
         "python"
@@ -22,14 +22,23 @@ fn main() {
         .env("PYTHONPATH", &mako)
         .env("TEMPLATE", &template)
         .arg("-c")
-        .arg("from os import environ; from mako.template import Template; \
-              from mako import exceptions; \n\
-              try:\n    print(Template(filename=environ['TEMPLATE']).render());\n\
-              except:\n    print exceptions.html_error_template().render()")
+        .arg(r#"
+import os
+import sys
+from mako.template import Template
+from mako import exceptions
+try:
+    print(Template(filename=os.environ['TEMPLATE'], input_encoding='utf8').render().encode('utf8'))
+except:
+    sys.stderr.write(exceptions.text_error_template().render().encode('utf8'))
+    sys.exit(1)
+"#)
         .stderr(Stdio::inherit())
         .output()
         .unwrap();
-    assert!(result.status.success());
+    if !result.status.success() {
+        exit(1)
+    }
     let out = env::var("OUT_DIR").unwrap();
     File::create(&Path::new(&out).join("properties.rs")).unwrap().write_all(&result.stdout).unwrap();
 }

components/style/properties.mako.rs

@@ -5534,6 +5534,15 @@ pub fn parse_style_attribute(input: &str, base_url: &Url) -> PropertyDeclaration
     parse_property_declaration_list(&context, &mut Parser::new(input))
 }
 
+pub fn parse_one_declaration(name: &str, input: &str, base_url: &Url)
+                             -> Result<Vec<PropertyDeclaration>, ()> {
+    let context = ParserContext::new(Origin::Author, base_url);
+    let mut results = vec![];
+    match PropertyDeclaration::parse(name, &context, &mut Parser::new(input), &mut results) {
+        PropertyDeclarationParseResult::ValidOrIgnoredDeclaration => Ok(results),
+        _ => Err(())
+    }
+}
 
 struct PropertyDeclarationParser<'a, 'b: 'a> {
     context: &'a ParserContext<'b>,
@@ -5574,9 +5583,9 @@ pub fn parse_property_declaration_list(context: &ParserContext, input: &mut Pars
         match declaration {
             Ok((results, important)) => {
                 if important {
-                    important_declarations.push_all(&results);
+                    important_declarations.extend(results);
                 } else {
-                    normal_declarations.push_all(&results);
+                    normal_declarations.extend(results);
                 }
             }
             Err(range) => {
@@ -5660,7 +5669,7 @@ impl<T: ToCss> DeclaredValue<T> {
     }
 }
 
-#[derive(Clone, PartialEq)]
+#[derive(PartialEq)]
 pub enum PropertyDeclaration {
     % for property in LONGHANDS:
         ${property.camel_case}(DeclaredValue<longhands::${property.ident}::SpecifiedValue>),
@@ -6543,11 +6552,12 @@ pub fn modify_style_for_inline_sides(style: &mut Arc<ComputedValues>,
 }
 
 pub fn is_supported_property(property: &str) -> bool {
-    match property {
-        % for property in SHORTHANDS + LONGHANDS:
+    match_ignore_ascii_case! { property,
+        % for property in SHORTHANDS + LONGHANDS[:-1]:
             "${property.name}" => true,
         % endfor
-        _ => false,
+        "${LONGHANDS[-1].name}" => true
+        _ => false
     }
 }
 
@@ -6579,16 +6589,24 @@ macro_rules! longhand_properties_idents {
     }
 }
 
-pub fn longhands_from_shorthand(shorthand: &str) -> Option<Vec<String>> {
-    match shorthand {
-        % for property in SHORTHANDS:
-            "${property.name}" => Some(vec!(
+// Extra space here because < seems to be removed by Mako when immediately followed by &.
+//                                                         ↓
+pub fn longhands_from_shorthand(shorthand: &str) -> Option< &'static [&'static str]> {
+    % for property in SHORTHANDS:
+        static ${property.ident.upper()}: &'static [&'static str] = &[
             % for sub in property.sub_properties:
-                "${sub.name}".to_owned(),
+                "${sub.name}",
             % endfor
-            )),
+        ];
+    % endfor
+    match_ignore_ascii_case!{ shorthand,
+        % for property in SHORTHANDS[:-1]:
+            "${property.name}" => Some(${property.ident.upper()}),
         % endfor
-        _ => None,
+        % for property in SHORTHANDS[-1:]:
+            "${property.name}" => Some(${property.ident.upper()})
+        % endfor
+        _ => None
     }
 }