servo: Merge #17430 - Store font-weight as integer directly (from upsuper:font-weight-int); r=nox

It doesn't make much sense to store `font-weight` as separate enums, especially given that we would need to support (somehow) arbitrary font weight value when we implement CSS Fonts Level 4.

This PR refactors the `font-weight` a bit to make it store as `u16` directly.

Source-Repo: https://github.com/servo/servo
Source-Revision: f11a922760a08ffb956607d9ab447f8f2a319a25

--HG--
extra : subtree_source : https%3A//hg.mozilla.org/projects/converted-servo-linear
extra : subtree_revision : 2c8f317216c5c66b2ced1f308efe14ff61fb3add

servo/components/gfx/font_template.rs

@@ -46,7 +46,7 @@ impl FontTemplateDescriptor {
             // A value higher than all weights.
             return 1000
         }
-        ((self.weight as i16) - (other.weight as i16)).abs() as u32
+        ((self.weight.0 as i16) - (other.weight.0 as i16)).abs() as u32
     }
 }
 

servo/components/gfx/platform/freetype/font.rs

@@ -128,7 +128,7 @@ impl FontHandleMethods for FontHandle {
         unsafe { (*self.face).style_flags & FT_STYLE_FLAG_ITALIC as c_long != 0 }
     }
     fn boldness(&self) -> font_weight::T {
-        let default_weight = font_weight::T::Weight400;
+        let default_weight = font_weight::T::normal();
         if unsafe { (*self.face).style_flags & FT_STYLE_FLAG_BOLD as c_long == 0 } {
             default_weight
         } else {
@@ -136,18 +136,13 @@ impl FontHandleMethods for FontHandle {
                 let os2 = FT_Get_Sfnt_Table(self.face, FT_Sfnt_Tag::FT_SFNT_OS2) as *mut TT_OS2;
                 let valid = !os2.is_null() && (*os2).version != 0xffff;
                 if valid {
-                    let weight =(*os2).usWeightClass;
-                    match weight {
-                        1 | 100...199 => font_weight::T::Weight100,
-                        2 | 200...299 => font_weight::T::Weight200,
-                        3 | 300...399 => font_weight::T::Weight300,
-                        4 | 400...499 => font_weight::T::Weight400,
-                        5 | 500...599 => font_weight::T::Weight500,
-                        6 | 600...699 => font_weight::T::Weight600,
-                        7 | 700...799 => font_weight::T::Weight700,
-                        8 | 800...899 => font_weight::T::Weight800,
-                        9 | 900...999 => font_weight::T::Weight900,
-                        _ => default_weight
+                    let weight =(*os2).usWeightClass as i32;
+                    if weight < 10 {
+                        font_weight::T::from_int(weight * 100).unwrap()
+                    } else if weight >= 100 && weight < 1000 {
+                        font_weight::T::from_int(weight / 100 * 100).unwrap()
+                    } else {
+                        default_weight
                     }
                 } else {
                     default_weight

servo/components/gfx/platform/macos/font.rs

@@ -217,17 +217,7 @@ impl FontHandleMethods for FontHandle {
         } else {
             4.0 + normalized * 5.0  // [4.0, 9.0]
         }; // [1.0, 9.0], centered on 4.0
-        match normalized.round() as u32 {
-            1 => font_weight::T::Weight100,
-            2 => font_weight::T::Weight200,
-            3 => font_weight::T::Weight300,
-            4 => font_weight::T::Weight400,
-            5 => font_weight::T::Weight500,
-            6 => font_weight::T::Weight600,
-            7 => font_weight::T::Weight700,
-            8 => font_weight::T::Weight800,
-            _ => font_weight::T::Weight900,
-        }
+        font_weight::T::from_int(normalized.round() as i32 * 100).unwrap()
     }
 
     fn stretchiness(&self) -> font_stretch::T {

servo/components/gfx/platform/windows/font.rs

@@ -155,18 +155,8 @@ impl FontInfo {
             },
         };
 
-        let weight = match min(9, max(1, weight_val / 100)) {
-            1 => font_weight::T::Weight100,
-            2 => font_weight::T::Weight200,
-            3 => font_weight::T::Weight300,
-            4 => font_weight::T::Weight400,
-            5 => font_weight::T::Weight500,
-            6 => font_weight::T::Weight600,
-            7 => font_weight::T::Weight700,
-            8 => font_weight::T::Weight800,
-            9 => font_weight::T::Weight900,
-            _ => return Err(()),
-        };
+        let weight = font_weight::T::
+            from_int(min(9, max(1, weight_val as i32 / 100)) * 100).unwrap();
 
         let stretch = match min(9, max(1, width_val)) {
             1 => font_stretch::T::ultra_condensed,
@@ -198,21 +188,21 @@ impl FontInfo {
 
     fn new_from_font(font: &Font) -> Result<FontInfo, ()> {
         let style = font.style();
-        let weight = match font.weight() {
-            FontWeight::Thin => font_weight::T::Weight100,
-            FontWeight::ExtraLight => font_weight::T::Weight200,
-            FontWeight::Light => font_weight::T::Weight300,
+        let weight = font_weight::T(match font.weight() {
+            FontWeight::Thin => 100,
+            FontWeight::ExtraLight => 200,
+            FontWeight::Light => 300,
             // slightly grayer gray
-            FontWeight::SemiLight => font_weight::T::Weight300,
-            FontWeight::Regular => font_weight::T::Weight400,
-            FontWeight::Medium => font_weight::T::Weight500,
-            FontWeight::SemiBold => font_weight::T::Weight600,
-            FontWeight::Bold => font_weight::T::Weight700,
-            FontWeight::ExtraBold => font_weight::T::Weight800,
-            FontWeight::Black => font_weight::T::Weight900,
+            FontWeight::SemiLight => 300,
+            FontWeight::Regular => 400,
+            FontWeight::Medium => 500,
+            FontWeight::SemiBold => 600,
+            FontWeight::Bold => 700,
+            FontWeight::ExtraBold => 800,
+            FontWeight::Black => 900,
             // slightly blacker black
-            FontWeight::ExtraBlack => font_weight::T::Weight900,
-        };
+            FontWeight::ExtraBlack => 900,
+        });
         let stretch = match font.stretch() {
             FontStretch::Undefined => font_stretch::T::normal,
             FontStretch::UltraCondensed => font_stretch::T::ultra_condensed,

servo/components/style/font_face.rs

@@ -109,29 +109,13 @@ impl Parse for FontWeight {
             }
         });
         result.or_else(|_| {
-            FontWeight::from_int(input.expect_integer()?)
+            font_weight::T::from_int(input.expect_integer()?)
+                .map(FontWeight::Weight)
                 .map_err(|()| StyleParseError::UnspecifiedError.into())
         })
     }
 }
 
-#[cfg(feature = "gecko")]
-impl FontWeight {
-    fn from_int(kw: i32) -> Result<Self, ()> {
-        match kw {
-            100 => Ok(FontWeight::Weight(font_weight::T::Weight100)),
-            200 => Ok(FontWeight::Weight(font_weight::T::Weight200)),
-            300 => Ok(FontWeight::Weight(font_weight::T::Weight300)),
-            400 => Ok(FontWeight::Weight(font_weight::T::Weight400)),
-            500 => Ok(FontWeight::Weight(font_weight::T::Weight500)),
-            600 => Ok(FontWeight::Weight(font_weight::T::Weight600)),
-            700 => Ok(FontWeight::Weight(font_weight::T::Weight700)),
-            800 => Ok(FontWeight::Weight(font_weight::T::Weight800)),
-            900 => Ok(FontWeight::Weight(font_weight::T::Weight900)),
-            _ => Err(())
-        }
-    }
-}
 /// Parse the block inside a `@font-face` rule.
 ///
 /// Note that the prelude parsing code lives in the `stylesheets` module.

servo/components/style/gecko/rules.rs

@@ -31,7 +31,7 @@ impl ToNsCssValue for FamilyName {
 
 impl ToNsCssValue for font_weight::T {
     fn convert(self, nscssvalue: &mut nsCSSValue) {
-        nscssvalue.set_integer(self as i32)
+        nscssvalue.set_integer(self.0 as i32)
     }
 }
 
@@ -42,7 +42,7 @@ impl ToNsCssValue for FontWeight {
                 nscssvalue.set_enum(structs::NS_STYLE_FONT_WEIGHT_NORMAL as i32),
             FontWeight::Bold =>
                 nscssvalue.set_enum(structs::NS_STYLE_FONT_WEIGHT_BOLD as i32),
-            FontWeight::Weight(weight) => nscssvalue.set_integer(weight as i32),
+            FontWeight::Weight(weight) => nscssvalue.set_integer(weight.0 as i32),
         }
     }
 }

servo/components/style/properties/gecko.mako.rs

@@ -1906,7 +1906,7 @@ fn static_assert() {
     }
 
     pub fn set_font_weight(&mut self, v: longhands::font_weight::computed_value::T) {
-        self.gecko.mFont.weight = v as u16;
+        self.gecko.mFont.weight = v.0;
     }
     ${impl_simple_copy('font_weight', 'mFont.weight')}
 

servo/components/style/properties/helpers/animated_properties.mako.rs

@@ -1415,38 +1415,21 @@ impl Animatable for MaxLength {
 impl Animatable for FontWeight {
     #[inline]
     fn add_weighted(&self, other: &Self, self_portion: f64, other_portion: f64) -> Result<Self, ()> {
-        let a = (*self as u32) as f64;
-        let b = (*other as u32) as f64;
+        let a = self.0 as f64;
+        let b = other.0 as f64;
         const NORMAL: f64 = 400.;
         let weight = (a - NORMAL) * self_portion + (b - NORMAL) * other_portion + NORMAL;
-        Ok(if weight < 150. {
-            FontWeight::Weight100
-        } else if weight < 250. {
-            FontWeight::Weight200
-        } else if weight < 350. {
-            FontWeight::Weight300
-        } else if weight < 450. {
-            FontWeight::Weight400
-        } else if weight < 550. {
-            FontWeight::Weight500
-        } else if weight < 650. {
-            FontWeight::Weight600
-        } else if weight < 750. {
-            FontWeight::Weight700
-        } else if weight < 850. {
-            FontWeight::Weight800
-        } else {
-            FontWeight::Weight900
-        })
+        let weight = (weight.min(100.).max(900.) / 100.).round() * 100.;
+        Ok(FontWeight(weight as u16))
     }
 
     #[inline]
-    fn get_zero_value(&self) -> Result<Self, ()> { Ok(FontWeight::Weight400) }
+    fn get_zero_value(&self) -> Result<Self, ()> { Ok(FontWeight::normal()) }
 
     #[inline]
     fn compute_distance(&self, other: &Self) -> Result<f64, ()> {
-        let a = (*self as u32) as f64;
-        let b = (*other as u32) as f64;
+        let a = self.0 as f64;
+        let b = other.0 as f64;
         a.compute_distance(&b)
     }
 }

servo/components/style/properties/longhand/font.mako.rs

@@ -422,9 +422,7 @@ ${helpers.single_keyword_system("font-variant-caps",
         Bold,
         Bolder,
         Lighter,
-        % for weight in range(100, 901, 100):
-            Weight${weight},
-        % endfor
+        Weight(computed_value::T),
         System(SystemFont),
     }
 
@@ -435,16 +433,14 @@ ${helpers.single_keyword_system("font-variant-caps",
                 SpecifiedValue::Bold => dest.write_str("bold"),
                 SpecifiedValue::Bolder => dest.write_str("bolder"),
                 SpecifiedValue::Lighter => dest.write_str("lighter"),
-                % for weight in range(100, 901, 100):
-                    SpecifiedValue::Weight${weight} => dest.write_str("${weight}"),
-                % endfor
+                SpecifiedValue::Weight(weight) => weight.to_css(dest),
                 SpecifiedValue::System(_) => Ok(())
             }
         }
     }
 
     /// normal | bold | bolder | lighter | 100 | 200 | 300 | 400 | 500 | 600 | 700 | 800 | 900
-    pub fn parse<'i, 't>(_context: &ParserContext, input: &mut Parser<'i, 't>)
+    pub fn parse<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
                          -> Result<SpecifiedValue, ParseError<'i>> {
         let result = input.try(|input| {
             let ident = input.expect_ident().map_err(|_| ())?;
@@ -456,25 +452,13 @@ ${helpers.single_keyword_system("font-variant-caps",
                 _ => Err(())
             }
         });
-        result.or_else(|_| {
-            SpecifiedValue::from_int(input.expect_integer()?)
-                .map_err(|()| StyleParseError::UnspecifiedError.into())
-        })
+        result.or_else(|_| computed_value::T::parse(context, input).map(SpecifiedValue::Weight))
     }
 
     impl SpecifiedValue {
-        pub fn from_int(kw: i32) -> Result<Self, ()> {
-            match kw {
-                % for weight in range(100, 901, 100):
-                    ${weight} => Ok(SpecifiedValue::Weight${weight}),
-                % endfor
-                _ => Err(())
-            }
-        }
-
         pub fn from_gecko_keyword(kw: u32) -> Self {
-            Self::from_int(kw as i32).expect("Found unexpected value in style
-                                              struct for font-weight property")
+            computed_value::T::from_int(kw as i32).map(SpecifiedValue::Weight)
+                .expect("Found unexpected value in style struct for font-weight property")
         }
     }
 
@@ -491,64 +475,79 @@ ${helpers.single_keyword_system("font-variant-caps",
         }
     }
 
-    /// Used in @font-face, where relative keywords are not allowed.
-    impl Parse for computed_value::T {
-        fn parse<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>) -> Result<Self, ParseError<'i>> {
-            match parse(context, input)? {
-                % for weight in range(100, 901, 100):
-                    SpecifiedValue::Weight${weight} => Ok(computed_value::T::Weight${weight}),
-                % endfor
-                SpecifiedValue::Normal => Ok(computed_value::T::Weight400),
-                SpecifiedValue::Bold => Ok(computed_value::T::Weight700),
-                SpecifiedValue::Bolder |
-                SpecifiedValue::Lighter => Err(StyleParseError::UnspecifiedError.into()),
-                SpecifiedValue::System(..) => unreachable!(),
-            }
-        }
-    }
-
     pub mod computed_value {
-        #[derive(PartialEq, Eq, Copy, Clone, Hash, Debug)]
+        /// As of CSS Fonts Module Level 3, only the following values are
+        /// valid: 100 | 200 | 300 | 400 | 500 | 600 | 700 | 800 | 900
+        #[derive(Clone, Copy, Debug, PartialEq, Eq, Hash, ToCss)]
         #[cfg_attr(feature = "servo", derive(HeapSizeOf, Deserialize, Serialize))]
-        #[repr(u16)]
-        pub enum T {
-            % for weight in range(100, 901, 100):
-                Weight${weight} = ${weight},
-            % endfor
-        }
+        pub struct T(pub u16);
+
         impl T {
-            #[inline]
-            pub fn is_bold(self) -> bool {
-                match self {
-                    T::Weight900 | T::Weight800 |
-                    T::Weight700 | T::Weight600 => true,
-                    _ => false
+            /// Value for normal
+            pub fn normal() -> Self {
+                T(400)
+            }
+
+            /// Value for bold
+            pub fn bold() -> Self {
+                T(700)
+            }
+
+            /// Convert from an integer to Weight
+            pub fn from_int(n: i32) -> Result<Self, ()> {
+                if n >= 100 && n <= 900 && n % 100 == 0 {
+                    Ok(T(n as u16))
+                } else {
+                    Err(())
                 }
             }
 
-            /// Obtain a Servo computed value from a Gecko computed font-weight
+            /// Convert from an Gecko weight
             pub fn from_gecko_weight(weight: u16) -> Self {
-                match weight {
-                    % for weight in range(100, 901, 100):
-                        ${weight} => T::Weight${weight},
-                    % endfor
-                    _ => panic!("from_gecko_weight: called with invalid weight")
+                Self::from_int(weight as i32)
+                    .expect("from_gecko_weight: called with invalid weight")
+            }
+
+            /// Weither this weight is bold
+            pub fn is_bold(&self) -> bool {
+                self.0 > 500
+            }
+
+            /// Return the bolder weight
+            pub fn bolder(self) -> Self {
+                if self.0 < 400 {
+                    T(400)
+                } else if self.0 < 600 {
+                    T(700)
+                } else {
+                    T(900)
+                }
+            }
+
+            /// Returns the lighter weight
+            pub fn lighter(self) -> Self {
+                if self.0 < 600 {
+                    T(100)
+                } else if self.0 < 800 {
+                    T(400)
+                } else {
+                    T(700)
                 }
             }
         }
     }
-    impl ToCss for computed_value::T {
-        fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
-            match *self {
-                % for weight in range(100, 901, 100):
-                    computed_value::T::Weight${weight} => dest.write_str("${weight}"),
-                % endfor
+
+    impl Parse for computed_value::T {
+        fn parse<'i, 't>(_: &ParserContext, input: &mut Parser<'i, 't>)
+            -> Result<Self, ParseError<'i>> {
+                Self::from_int(input.expect_integer()?)
+                    .map_err(|_| StyleParseError::UnspecifiedError.into())
             }
-        }
     }
+
     #[inline]
     pub fn get_initial_value() -> computed_value::T {
-        computed_value::T::Weight400  // normal
+        computed_value::T::normal()
     }
 
     #[inline]
@@ -562,33 +561,13 @@ ${helpers.single_keyword_system("font-variant-caps",
         #[inline]
         fn to_computed_value(&self, context: &Context) -> computed_value::T {
             match *self {
-                % for weight in range(100, 901, 100):
-                    SpecifiedValue::Weight${weight} => computed_value::T::Weight${weight},
-                % endfor
-                SpecifiedValue::Normal => computed_value::T::Weight400,
-                SpecifiedValue::Bold => computed_value::T::Weight700,
-                SpecifiedValue::Bolder => match context.inherited_style().get_font().clone_font_weight() {
-                    computed_value::T::Weight100 => computed_value::T::Weight400,
-                    computed_value::T::Weight200 => computed_value::T::Weight400,
-                    computed_value::T::Weight300 => computed_value::T::Weight400,
-                    computed_value::T::Weight400 => computed_value::T::Weight700,
-                    computed_value::T::Weight500 => computed_value::T::Weight700,
-                    computed_value::T::Weight600 => computed_value::T::Weight900,
-                    computed_value::T::Weight700 => computed_value::T::Weight900,
-                    computed_value::T::Weight800 => computed_value::T::Weight900,
-                    computed_value::T::Weight900 => computed_value::T::Weight900,
-                },
-                SpecifiedValue::Lighter => match context.inherited_style().get_font().clone_font_weight() {
-                    computed_value::T::Weight100 => computed_value::T::Weight100,
-                    computed_value::T::Weight200 => computed_value::T::Weight100,
-                    computed_value::T::Weight300 => computed_value::T::Weight100,
-                    computed_value::T::Weight400 => computed_value::T::Weight100,
-                    computed_value::T::Weight500 => computed_value::T::Weight100,
-                    computed_value::T::Weight600 => computed_value::T::Weight400,
-                    computed_value::T::Weight700 => computed_value::T::Weight400,
-                    computed_value::T::Weight800 => computed_value::T::Weight700,
-                    computed_value::T::Weight900 => computed_value::T::Weight700,
-                },
+                SpecifiedValue::Weight(weight) => weight,
+                SpecifiedValue::Normal => computed_value::T::normal(),
+                SpecifiedValue::Bold => computed_value::T::bold(),
+                SpecifiedValue::Bolder =>
+                    context.inherited_style().get_font().clone_font_weight().bolder(),
+                SpecifiedValue::Lighter =>
+                    context.inherited_style().get_font().clone_font_weight().lighter(),
                 SpecifiedValue::System(_) => {
                     <%self:nongecko_unreachable>
                         context.cached_system_font.as_ref().unwrap().font_weight.clone()
@@ -599,11 +578,7 @@ ${helpers.single_keyword_system("font-variant-caps",
 
         #[inline]
         fn from_computed_value(computed: &computed_value::T) -> Self {
-            match *computed {
-                % for weight in range(100, 901, 100):
-                    computed_value::T::Weight${weight} => SpecifiedValue::Weight${weight},
-                % endfor
-            }
+            SpecifiedValue::Weight(*computed)
         }
     }
 </%helpers:longhand>

servo/components/style/properties/properties.mako.rs

@@ -1673,7 +1673,7 @@ pub mod style_structs {
                     // Corresponds to the fields in
                     // `gfx::font_template::FontTemplateDescriptor`.
                     let mut hasher: FnvHasher = Default::default();
-                    hasher.write_u16(self.font_weight as u16);
+                    hasher.write_u16(self.font_weight.0);
                     self.font_stretch.hash(&mut hasher);
                     self.font_family.hash(&mut hasher);
                     self.hash = hasher.finish()

servo/components/style/style_adjuster.rs

@@ -184,7 +184,7 @@ impl<'a, 'b: 'a> StyleAdjuster<'a, 'b> {
             let mut font_style = self.style.mutate_font();
             // Sadly we don't have a nice name for the computed value
             // of "font-weight: normal".
-            font_style.set_font_weight(font_weight::Weight400);
+            font_style.set_font_weight(font_weight::normal());
             font_style.set_font_style(font_style::normal);
         }
     }