Auto merge of #15976 - Manishearth:stylo-stub-system-metric, r=heycam

stylo: Add parsing support for functional non-ts pseudoclasses, add stub -moz-system-metric pseudo

r=heycam from https://bugzilla.mozilla.org/show_bug.cgi?id=1341086

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3 files changed, 79 insertions, 32 deletions

diff --git a/components/style/gecko/non_ts_pseudo_class_list.rs b/components/style/gecko/non_ts_pseudo_class_list.rs
index ef0ec883d3d..0fc580cdc08 100644
--- a/components/style/gecko/non_ts_pseudo_class_list.rs
+++ b/components/style/gecko/non_ts_pseudo_class_list.rs
@@ -11,18 +11,18 @@
  *
  * Expected usage is as follows:
  * ```
- * fn use_pseudo_class() {
- *     macro_rules! use_pseudo_class_list {
- *         ( $(
- *             ($css:expr, $name:ident, $gecko_type:tt, $state:tt, $flags:tt),
- *         )* ) => {
- *             // Do stuff.
- *         }
+ * macro_rules! pseudo_class_macro{
+ *     (bare: [$(($css:expr, $name:ident, $gecko_type:tt, $state:tt, $flags:tt),)*],
+ *      string: [$(($s_css:expr, $s_name:ident, $s_gecko_type:tt, $s_state:tt, $s_flags:tt),)*]) => {
+ *         // do stuff
  *     }
- *     apply_non_ts_list!(use_pseudo_class_list)
  * }
+ * apply_non_ts_list!(pseudo_class_macro)
  * ```
  *
+ * The string variables will be applied to pseudoclasses that are of the form
+ * of a function with a string argument.
+ *
  * $gecko_type can be either "_" or an ident in Gecko's CSSPseudoClassType.
  * $state can be either "_" or an expression of type ElementState.
  * $flags can be either "_" or an expression of type NonTSPseudoClassFlag,
@@ -32,22 +32,27 @@
 macro_rules! apply_non_ts_list {
     ($apply_macro:ident) => {
         $apply_macro! {
-            ("any-link", AnyLink, anyLink, _, _),
-            ("link", Link, link, _, _),
-            ("visited", Visited, visited, _, _),
-            ("active", Active, active, IN_ACTIVE_STATE, _),
-            ("focus", Focus, focus, IN_FOCUS_STATE, _),
-            ("fullscreen", Fullscreen, fullscreen, IN_FULLSCREEN_STATE, _),
-            ("hover", Hover, hover, IN_HOVER_STATE, _),
-            ("enabled", Enabled, enabled, IN_ENABLED_STATE, _),
-            ("disabled", Disabled, disabled, IN_DISABLED_STATE, _),
-            ("checked", Checked, checked, IN_CHECKED_STATE, _),
-            ("indeterminate", Indeterminate, indeterminate, IN_INDETERMINATE_STATE, _),
-            ("read-write", ReadWrite, _, IN_READ_WRITE_STATE, _),
-            ("read-only", ReadOnly, _, IN_READ_WRITE_STATE, _),
+            bare: [
+                ("any-link", AnyLink, anyLink, _, _),
+                ("link", Link, link, _, _),
+                ("visited", Visited, visited, _, _),
+                ("active", Active, active, IN_ACTIVE_STATE, _),
+                ("focus", Focus, focus, IN_FOCUS_STATE, _),
+                ("fullscreen", Fullscreen, fullscreen, IN_FULLSCREEN_STATE, _),
+                ("hover", Hover, hover, IN_HOVER_STATE, _),
+                ("enabled", Enabled, enabled, IN_ENABLED_STATE, _),
+                ("disabled", Disabled, disabled, IN_DISABLED_STATE, _),
+                ("checked", Checked, checked, IN_CHECKED_STATE, _),
+                ("indeterminate", Indeterminate, indeterminate, IN_INDETERMINATE_STATE, _),
+                ("read-write", ReadWrite, _, IN_READ_WRITE_STATE, _),
+                ("read-only", ReadOnly, _, IN_READ_WRITE_STATE, _),
 
-            ("-moz-browser-frame", MozBrowserFrame, mozBrowserFrame, _, PSEUDO_CLASS_INTERNAL),
-            ("-moz-table-border-nonzero", MozTableBorderNonzero, mozTableBorderNonzero, _, PSEUDO_CLASS_INTERNAL),
+                ("-moz-browser-frame", MozBrowserFrame, mozBrowserFrame, _, PSEUDO_CLASS_INTERNAL),
+                ("-moz-table-border-nonzero", MozTableBorderNonzero, mozTableBorderNonzero, _, PSEUDO_CLASS_INTERNAL),
+            ],
+            string: [
+                ("-moz-system-metric", MozSystemMetric, mozSystemMetric, _, PSEUDO_CLASS_INTERNAL),
+            ]
         }
     }
 }
diff --git a/components/style/gecko/selector_parser.rs b/components/style/gecko/selector_parser.rs
index efed114f657..d465b7fa791 100644
--- a/components/style/gecko/selector_parser.rs
+++ b/components/style/gecko/selector_parser.rs
@@ -4,7 +4,7 @@
 
 //! Gecko-specific bits for selector-parsing.
 
-use cssparser::ToCss;
+use cssparser::{Parser, ToCss};
 use element_state::ElementState;
 use gecko_bindings::structs::CSSPseudoClassType;
 use gecko_bindings::structs::nsIAtom;
@@ -139,7 +139,8 @@ bitflags! {
 }
 
 macro_rules! pseudo_class_name {
-    ($(($css:expr, $name:ident, $_gecko_type:tt, $_state:tt, $_flags:tt),)*) => {
+    (bare: [$(($css:expr, $name:ident, $gecko_type:tt, $state:tt, $flags:tt),)*],
+     string: [$(($s_css:expr, $s_name:ident, $s_gecko_type:tt, $s_state:tt, $s_flags:tt),)*]) => {
         #[doc = "Our representation of a non tree-structural pseudo-class."]
         #[derive(Clone, Debug, PartialEq, Eq, Hash)]
         pub enum NonTSPseudoClass {
@@ -147,6 +148,10 @@ macro_rules! pseudo_class_name {
                 #[doc = $css]
                 $name,
             )*
+            $(
+                #[doc = $s_css]
+                $s_name(Box<str>),
+            )*
         }
     }
 }
@@ -155,13 +160,18 @@ apply_non_ts_list!(pseudo_class_name);
 impl ToCss for NonTSPseudoClass {
     fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
         macro_rules! pseudo_class_serialize {
-            ($(($css:expr, $name:ident, $_gecko_type:tt, $_state:tt, $_flags:tt),)*) => {
+            (bare: [$(($css:expr, $name:ident, $gecko_type:tt, $state:tt, $flags:tt),)*],
+             string: [$(($s_css:expr, $s_name:ident, $s_gecko_type:tt, $s_state:tt, $s_flags:tt),)*]) => {
                 match *self {
                     $(NonTSPseudoClass::$name => concat!(":", $css),)*
+                    $(NonTSPseudoClass::$s_name(ref s) => {
+                        return dest.write_str(&format!(":{}({})", $s_css, s))
+                    }, )*
                 }
             }
         }
-        dest.write_str(apply_non_ts_list!(pseudo_class_serialize))
+        let ser = apply_non_ts_list!(pseudo_class_serialize);
+        dest.write_str(ser)
     }
 }
 
@@ -174,9 +184,11 @@ impl NonTSPseudoClass {
             ($flags:expr) => ($flags.contains(PSEUDO_CLASS_INTERNAL));
         }
         macro_rules! pseudo_class_check_internal {
-            ($(($_css:expr, $name:ident, $_gecko_type:tt, $_state:tt, $flags:tt),)*) => {
+            (bare: [$(($css:expr, $name:ident, $gecko_type:tt, $state:tt, $flags:tt),)*],
+            string: [$(($s_css:expr, $s_name:ident, $s_gecko_type:tt, $s_state:tt, $s_flags:tt),)*]) => {
                 match *self {
                     $(NonTSPseudoClass::$name => check_flag!($flags),)*
+                    $(NonTSPseudoClass::$s_name(..) => check_flag!($s_flags),)*
                 }
             }
         }
@@ -190,9 +202,11 @@ impl NonTSPseudoClass {
             ($state:ident) => (::element_state::$state);
         }
         macro_rules! pseudo_class_state {
-            ($(($_css:expr, $name:ident, $_gecko_type:tt, $state:tt, $_flags:tt),)*) => {
+            (bare: [$(($css:expr, $name:ident, $gecko_type:tt, $state:tt, $flags:tt),)*],
+            string: [$(($s_css:expr, $s_name:ident, $s_gecko_type:tt, $s_state:tt, $s_flags:tt),)*]) => {
                 match *self {
                     $(NonTSPseudoClass::$name => flag!($state),)*
+                    $(NonTSPseudoClass::$s_name(..) => flag!($s_state),)*
                 }
             }
         }
@@ -207,9 +221,11 @@ impl NonTSPseudoClass {
                 (Some(::gecko_bindings::structs::CSSPseudoClassType::$gecko_type));
         }
         macro_rules! pseudo_class_geckotype {
-            ($(($_css:expr, $name:ident, $gecko_type:tt, $_state:tt, $_flags:tt),)*) => {
+            (bare: [$(($css:expr, $name:ident, $gecko_type:tt, $state:tt, $flags:tt),)*],
+            string: [$(($s_css:expr, $s_name:ident, $s_gecko_type:tt, $s_state:tt, $s_flags:tt),)*]) => {
                 match *self {
                     $(NonTSPseudoClass::$name => gecko_type!($gecko_type),)*
+                    $(NonTSPseudoClass::$s_name(..) => gecko_type!($s_gecko_type),)*
                 }
             }
         }
@@ -249,7 +265,8 @@ impl<'a> ::selectors::Parser for SelectorParser<'a> {
 
     fn parse_non_ts_pseudo_class(&self, name: Cow<str>) -> Result<NonTSPseudoClass, ()> {
         macro_rules! pseudo_class_parse {
-            ($(($css:expr, $name:ident, $_gecko_type:tt, $_state:tt, $_flags:tt),)*) => {
+            (bare: [$(($css:expr, $name:ident, $gecko_type:tt, $state:tt, $flags:tt),)*],
+             string: [$(($s_css:expr, $s_name:ident, $s_gecko_type:tt, $s_state:tt, $s_flags:tt),)*]) => {
                 match_ignore_ascii_case! { &name,
                     $($css => NonTSPseudoClass::$name,)*
                     _ => return Err(())
@@ -264,6 +281,30 @@ impl<'a> ::selectors::Parser for SelectorParser<'a> {
         }
     }
 
+    fn parse_non_ts_functional_pseudo_class(&self,
+                                            name: Cow<str>,
+                                            parser: &mut Parser)
+                                            -> Result<NonTSPseudoClass, ()> {
+        macro_rules! pseudo_class_string_parse {
+            (bare: [$(($css:expr, $name:ident, $gecko_type:tt, $state:tt, $flags:tt),)*],
+             string: [$(($s_css:expr, $s_name:ident, $s_gecko_type:tt, $s_state:tt, $s_flags:tt),)*]) => {
+                match_ignore_ascii_case! { &name,
+                    $($s_css => {
+                        let name = String::from(parser.expect_ident_or_string()?).into_boxed_str();
+                        NonTSPseudoClass::$s_name(name)
+                    }, )*
+                    _ => return Err(())
+                }
+            }
+        }
+        let pseudo_class = apply_non_ts_list!(pseudo_class_string_parse);
+        if !pseudo_class.is_internal() || self.in_user_agent_stylesheet() {
+            Ok(pseudo_class)
+        } else {
+            Err(())
+        }
+    }
+
     fn parse_pseudo_element(&self, name: Cow<str>) -> Result<PseudoElement, ()> {
         match PseudoElement::from_slice(&name, self.in_user_agent_stylesheet()) {
             Some(pseudo) => Ok(pseudo),
diff --git a/components/style/gecko/wrapper.rs b/components/style/gecko/wrapper.rs
index 83cf8788bd4..2c1f07b28b1 100644
--- a/components/style/gecko/wrapper.rs
+++ b/components/style/gecko/wrapper.rs
@@ -661,7 +661,8 @@ impl<'le> ::selectors::Element for GeckoElement<'le> {
             NonTSPseudoClass::MozTableBorderNonzero |
             NonTSPseudoClass::MozBrowserFrame => unsafe {
                 Gecko_MatchesElement(pseudo_class.to_gecko_pseudoclasstype().unwrap(), self.0)
-            }
+            },
+            _ => false
         }
     }