Auto merge of #19165 - CYBAI:font-synthesis-out-of-mako, r=emilio

style: Move font-synthesis outside of mako

This is a sub-PR of #19015
r? emilio

---
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #19160  (github issue number if applicable).
- [x] These changes do not require tests

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

@@ -642,92 +642,13 @@ ${helpers.predefined_type("font-size-adjust",
                           flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
                           spec="https://drafts.csswg.org/css-fonts/#propdef-font-size-adjust")}
 
-<%helpers:longhand products="gecko" name="font-synthesis" animation_value_type="discrete"
-                   flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER"
-                   spec="https://drafts.csswg.org/css-fonts/#propdef-font-synthesis">
-    use std::fmt;
-    use style_traits::ToCss;
-
-    pub mod computed_value {
-        pub use super::SpecifiedValue as T;
-    }
-
-    #[derive(Clone, Debug, MallocSizeOf, PartialEq, ToComputedValue)]
-    pub struct SpecifiedValue {
-        pub weight: bool,
-        pub style: bool,
-    }
-
-    impl ToCss for computed_value::T {
-        fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
-            if self.weight && self.style {
-                dest.write_str("weight style")
-            } else if self.style {
-                dest.write_str("style")
-            } else if self.weight {
-                dest.write_str("weight")
-            } else {
-                dest.write_str("none")
-            }
-        }
-    }
-
-    #[inline]
-    pub fn get_initial_value() -> computed_value::T {
-        SpecifiedValue { weight: true, style: true }
-    }
-
-    pub fn parse<'i, 't>(_context: &ParserContext, input: &mut Parser<'i, 't>)
-                         -> Result<SpecifiedValue, ParseError<'i>> {
-        let mut result = SpecifiedValue { weight: false, style: false };
-        // FIXME: remove clone() when lifetimes are non-lexical
-        try_match_ident_ignore_ascii_case! { input,
-            "none" => Ok(result),
-            "weight" => {
-                result.weight = true;
-                if input.try(|input| input.expect_ident_matching("style")).is_ok() {
-                    result.style = true;
-                }
-                Ok(result)
-            },
-            "style" => {
-                result.style = true;
-                if input.try(|input| input.expect_ident_matching("weight")).is_ok() {
-                    result.weight = true;
-                }
-                Ok(result)
-            },
-        }
-    }
-
-    #[cfg(feature = "gecko")]
-    impl From<u8> for SpecifiedValue {
-        fn from(bits: u8) -> SpecifiedValue {
-            use gecko_bindings::structs;
-
-            SpecifiedValue {
-                weight: bits & structs::NS_FONT_SYNTHESIS_WEIGHT as u8 != 0,
-                style: bits & structs::NS_FONT_SYNTHESIS_STYLE as u8 != 0
-            }
-        }
-    }
-
-    #[cfg(feature = "gecko")]
-    impl From<SpecifiedValue> for u8 {
-        fn from(v: SpecifiedValue) -> u8 {
-            use gecko_bindings::structs;
-
-            let mut bits: u8 = 0;
-            if v.weight {
-                bits |= structs::NS_FONT_SYNTHESIS_WEIGHT as u8;
-            }
-            if v.style {
-                bits |= structs::NS_FONT_SYNTHESIS_STYLE as u8;
-            }
-            bits
-        }
-    }
-</%helpers:longhand>
+${helpers.predefined_type("font-synthesis",
+                          "FontSynthesis",
+                          products="gecko",
+                          initial_value="specified::FontSynthesis::get_initial_value()",
+                          animation_value_type="discrete",
+                          flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+                          spec="https://drafts.csswg.org/css-fonts/#propdef-font-synthesis")}
 
 ${helpers.single_keyword_system("font-stretch",
                                 "normal ultra-condensed extra-condensed condensed \

components/style/values/computed/font.rs

@@ -14,7 +14,7 @@ use values::specified::font as specified;
 use values::specified::length::{FontBaseSize, NoCalcLength};
 
 pub use values::computed::Length as MozScriptMinSize;
-pub use values::specified::font::XTextZoom;
+pub use values::specified::font::{XTextZoom, FontSynthesis};
 
 /// As of CSS Fonts Module Level 3, only the following values are
 /// valid: 100 | 200 | 300 | 400 | 500 | 600 | 700 | 800 | 900

components/style/values/computed/mod.rs

@@ -36,7 +36,7 @@ pub use self::angle::Angle;
 pub use self::background::{BackgroundSize, BackgroundRepeat};
 pub use self::border::{BorderImageSlice, BorderImageWidth, BorderImageSideWidth};
 pub use self::border::{BorderRadius, BorderCornerRadius, BorderSpacing};
-pub use self::font::{FontSize, FontSizeAdjust, FontWeight, MozScriptLevel, MozScriptMinSize, XTextZoom};
+pub use self::font::{FontSize, FontSizeAdjust, FontSynthesis, FontWeight, MozScriptLevel, MozScriptMinSize, XTextZoom};
 pub use self::box_::{AnimationIterationCount, AnimationName, ScrollSnapType, VerticalAlign};
 pub use self::color::{Color, ColorPropertyValue, RGBAColor};
 pub use self::effects::{BoxShadow, Filter, SimpleShadow};

components/style/values/specified/font.rs

@@ -610,6 +610,95 @@ impl Parse for FontSize {
     }
 }
 
+#[derive(Clone, Debug, MallocSizeOf, PartialEq, ToComputedValue)]
+/// Whether user agents are allowed to synthesize bold or oblique font faces
+/// when a font family lacks bold or italic faces
+pub struct FontSynthesis {
+    /// If a `font-weight` is requested that the font family does not contain,
+    /// the user agent may synthesize the requested weight from the weights
+    /// that do exist in the font family.
+    pub weight: bool,
+    /// If a font-style is requested that the font family does not contain,
+    /// the user agent may synthesize the requested style from the normal face in the font family.
+    pub style: bool,
+}
+
+impl FontSynthesis {
+    #[inline]
+    /// Get the default value of font-synthesis
+    pub fn get_initial_value() -> Self {
+        FontSynthesis {
+            weight: true,
+            style: true
+        }
+    }
+}
+
+impl Parse for FontSynthesis {
+    fn parse<'i, 't>(_: &ParserContext, input: &mut Parser<'i, 't>) -> Result<FontSynthesis, ParseError<'i>> {
+        let mut result = FontSynthesis { weight: false, style: false };
+        try_match_ident_ignore_ascii_case! { input,
+            "none" => Ok(result),
+            "weight" => {
+                result.weight = true;
+                if input.try(|input| input.expect_ident_matching("style")).is_ok() {
+                    result.style = true;
+                }
+                Ok(result)
+            },
+            "style" => {
+                result.style = true;
+                if input.try(|input| input.expect_ident_matching("weight")).is_ok() {
+                    result.weight = true;
+                }
+                Ok(result)
+            },
+        }
+    }
+}
+
+impl ToCss for FontSynthesis {
+    fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
+        if self.weight && self.style {
+            dest.write_str("weight style")
+        } else if self.style {
+            dest.write_str("style")
+        } else if self.weight {
+            dest.write_str("weight")
+        } else {
+            dest.write_str("none")
+        }
+    }
+}
+
+#[cfg(feature = "gecko")]
+impl From<u8> for FontSynthesis {
+    fn from(bits: u8) -> FontSynthesis {
+        use gecko_bindings::structs;
+
+        FontSynthesis {
+            weight: bits & structs::NS_FONT_SYNTHESIS_WEIGHT as u8 != 0,
+            style: bits & structs::NS_FONT_SYNTHESIS_STYLE as u8 != 0
+        }
+    }
+}
+
+#[cfg(feature = "gecko")]
+impl From<FontSynthesis> for u8 {
+    fn from(v: FontSynthesis) -> u8 {
+        use gecko_bindings::structs;
+
+        let mut bits: u8 = 0;
+        if v.weight {
+            bits |= structs::NS_FONT_SYNTHESIS_WEIGHT as u8;
+        }
+        if v.style {
+            bits |= structs::NS_FONT_SYNTHESIS_STYLE as u8;
+        }
+        bits
+    }
+}
+
 #[derive(Clone, Debug, MallocSizeOf, PartialEq, ToComputedValue)]
 /// text-zoom. Enable if true, disable if false
 pub struct XTextZoom(pub bool);

components/style/values/specified/mod.rs

@@ -30,7 +30,7 @@ pub use self::align::{AlignItems, AlignJustifyContent, AlignJustifySelf, Justify
 pub use self::background::{BackgroundRepeat, BackgroundSize};
 pub use self::border::{BorderCornerRadius, BorderImageSlice, BorderImageWidth};
 pub use self::border::{BorderImageSideWidth, BorderRadius, BorderSideWidth, BorderSpacing};
-pub use self::font::{FontSize, FontSizeAdjust, FontWeight, MozScriptLevel, MozScriptMinSize, XTextZoom};
+pub use self::font::{FontSize, FontSizeAdjust, FontSynthesis, FontWeight, MozScriptLevel, MozScriptMinSize, XTextZoom};
 pub use self::box_::{AnimationIterationCount, AnimationName, ScrollSnapType, VerticalAlign};
 pub use self::color::{Color, ColorPropertyValue, RGBAColor};
 pub use self::effects::{BoxShadow, Filter, SimpleShadow};