style: Use Rust types for Position.

This one should be much easier to review / much more pleasant to see :-)

Differential Revision: https://phabricator.services.mozilla.com/D19563

components/style/cbindgen.toml

@@ -82,6 +82,7 @@ include = [
   "Size",
   "MaxSize",
   "FlexBasis",
+  "Position",
 ]
 item_types = ["enums", "structs", "typedefs"]
 
@@ -90,6 +91,7 @@ item_types = ["enums", "structs", "typedefs"]
   // Defined in nsStyleCoord.h
   static constexpr inline StyleLengthPercentage Zero();
   static inline StyleLengthPercentage FromAppUnits(nscoord);
+  static inline StyleLengthPercentage FromPercentage(float);
   inline CSSCoord LengthInCSSPixels() const;
  private:
   inline nscoord LengthComponent() const;
@@ -103,8 +105,12 @@ item_types = ["enums", "structs", "typedefs"]
   inline float ToPercentage() const;
   inline CSSCoord ResolveToCSSPixels(CSSCoord aPercentageBasisInCSSPixels) const;
   template<typename T> inline CSSCoord ResolveToCSSPixelsWith(T aPercentageGetter) const;
+  template<typename T, typename U>
+  inline nscoord Resolve(T aPercentageGetter, U aPercentRoundingFunction) const;
+  template<typename T>
+  inline nscoord Resolve(nscoord aPercentageBasis, T aPercentRoundingFunction) const;
+  template<typename T> inline nscoord Resolve(T aPercentageGetter) const;
   inline nscoord Resolve(nscoord aPercentageBasis) const;
-  template<typename T> inline nscoord ResolveWith(T aPercentageGetter) const;
 """
 
 "GenericLengthPercentageOrAuto" = """
@@ -146,6 +152,11 @@ item_types = ["enums", "structs", "typedefs"]
   inline bool BehavesLikeInitialValueOnBlockAxis() const;
 """
 
+"GenericPosition" = """
+  inline bool DependsOnPositioningAreaSize() const;
+  static inline StyleGenericPosition FromPercentage(float);
+"""
+
 "Rect" = """
   // Defined in nsStyleCoord.h
   template<typename Predicate> inline bool All(Predicate) const;

components/style/gecko/conversions.rs

@@ -614,7 +614,6 @@ pub mod basic_shape {
     //! Conversions from and to CSS shape representations.
 
     use crate::gecko::values::GeckoStyleCoordConvertible;
-    use crate::gecko_bindings::structs;
     use crate::gecko_bindings::structs::{nsStyleCoord, nsStyleCorners};
     use crate::gecko_bindings::structs::{StyleBasicShape, StyleBasicShapeType};
     use crate::gecko_bindings::structs::{
@@ -628,7 +627,6 @@ pub mod basic_shape {
     use crate::values::computed::border::{BorderCornerRadius, BorderRadius};
     use crate::values::computed::length::LengthPercentage;
     use crate::values::computed::motion::OffsetPath;
-    use crate::values::computed::position;
     use crate::values::computed::url::ComputedUrl;
     use crate::values::generics::basic_shape::{
         BasicShape as GenericBasicShape, InsetRect, Polygon,
@@ -759,12 +757,12 @@ pub mod basic_shape {
                 },
                 StyleBasicShapeType::Circle => GenericBasicShape::Circle(Circle {
                     radius: (&other.mCoordinates[0]).into(),
-                    position: (&other.mPosition).into(),
+                    position: other.mPosition,
                 }),
                 StyleBasicShapeType::Ellipse => GenericBasicShape::Ellipse(Ellipse {
                     semiaxis_x: (&other.mCoordinates[0]).into(),
                     semiaxis_y: (&other.mCoordinates[1]).into(),
-                    position: (&other.mPosition).into(),
+                    position: other.mPosition,
                 }),
                 StyleBasicShapeType::Polygon => {
                     let mut coords = Vec::with_capacity(other.mCoordinates.len() / 2);
@@ -852,17 +850,6 @@ pub mod basic_shape {
         }
     }
 
-    // Can't be a From impl since we need to set an existing
-    // Position, not create a new one
-    impl From<position::Position> for structs::Position {
-        fn from(other: position::Position) -> Self {
-            structs::Position {
-                mXPosition: other.horizontal.into(),
-                mYPosition: other.vertical.into(),
-            }
-        }
-    }
-
     impl<'a> From<&'a nsStyleCoord> for ShapeRadius {
         fn from(other: &'a nsStyleCoord) -> Self {
             let other = other.borrow();
@@ -871,15 +858,6 @@ pub mod basic_shape {
         }
     }
 
-    impl<'a> From<&'a structs::Position> for position::Position {
-        fn from(other: &'a structs::Position) -> Self {
-            position::Position {
-                horizontal: other.mXPosition.into(),
-                vertical: other.mYPosition.into(),
-            }
-        }
-    }
-
     impl From<ShapeBox> for StyleGeometryBox {
         fn from(reference: ShapeBox) -> Self {
             use crate::gecko_bindings::structs::StyleGeometryBox::*;

components/style/properties/gecko.mako.rs

@@ -453,22 +453,6 @@ def set_gecko_property(ffi_name, expr):
     }
 </%def>
 
-<%def name="impl_position(ident, gecko_ffi_name)">
-    #[allow(non_snake_case)]
-    pub fn set_${ident}(&mut self, v: longhands::${ident}::computed_value::T) {
-        ${set_gecko_property("%s.mXPosition" % gecko_ffi_name, "v.horizontal.into()")}
-        ${set_gecko_property("%s.mYPosition" % gecko_ffi_name, "v.vertical.into()")}
-    }
-    <%call expr="impl_simple_copy(ident, gecko_ffi_name)"></%call>
-    #[allow(non_snake_case)]
-    pub fn clone_${ident}(&self) -> longhands::${ident}::computed_value::T {
-        longhands::${ident}::computed_value::T {
-            horizontal: self.gecko.${gecko_ffi_name}.mXPosition.into(),
-            vertical: self.gecko.${gecko_ffi_name}.mYPosition.into(),
-        }
-    }
-</%def>
-
 <%def name="impl_color(ident, gecko_ffi_name)">
 <%call expr="impl_color_setter(ident, gecko_ffi_name)"></%call>
 <%call expr="impl_color_copy(ident, gecko_ffi_name)"></%call>
@@ -1401,7 +1385,7 @@ impl Clone for ${style_struct.gecko_struct_name} {
         "OverflowWrap": impl_simple,
         "OverflowAnchor": impl_simple,
         "Perspective": impl_style_coord,
-        "Position": impl_position,
+        "Position": impl_simple,
         "RGBAColor": impl_rgba_color,
         "SVGLength": impl_svg_length,
         "SVGOpacity": impl_svg_opacity,
@@ -3095,11 +3079,7 @@ fn static_assert() {
         where I: IntoIterator<Item = longhands::scroll_snap_coordinate::computed_value::single_value::T>,
               I::IntoIter: ExactSizeIterator
     {
-        let iter = v.into_iter().map(|c| structs::mozilla::Position {
-            mXPosition: c.horizontal.into(),
-            mYPosition: c.vertical.into(),
-        });
-        self.gecko.mScrollSnapCoordinate.assign_from_iter_pod(iter);
+        self.gecko.mScrollSnapCoordinate.assign_from_iter_pod(v.into_iter());
     }
 
     pub fn copy_scroll_snap_coordinate_from(&mut self, other: &Self) {
@@ -3112,7 +3092,7 @@ fn static_assert() {
     }
 
     pub fn clone_scroll_snap_coordinate(&self) -> longhands::scroll_snap_coordinate::computed_value::T {
-        let vec = self.gecko.mScrollSnapCoordinate.iter().map(|f| f.into()).collect();
+        let vec = self.gecko.mScrollSnapCoordinate.iter().cloned().collect();
         longhands::scroll_snap_coordinate::computed_value::List(vec)
     }
 
@@ -3759,7 +3739,7 @@ fn static_assert() {
     <% impl_simple_image_array_property("clip", shorthand, image_layers_field, "mClip", struct_name) %>
     <% impl_simple_image_array_property("origin", shorthand, image_layers_field, "mOrigin", struct_name) %>
 
-    % for orientation in ["x", "y"]:
+    % for (orientation, keyword) in [("x", "horizontal"), ("y", "vertical")]:
     pub fn copy_${shorthand}_position_${orientation}_from(&mut self, other: &Self) {
         use crate::gecko_bindings::structs::nsStyleImageLayers_LayerType as LayerType;
 
@@ -3774,8 +3754,7 @@ fn static_assert() {
         for (layer, other) in self.gecko.${image_layers_field}.mLayers.iter_mut()
                                   .zip(other.gecko.${image_layers_field}.mLayers.iter())
                                   .take(count as usize) {
-            layer.mPosition.m${orientation.upper()}Position
-                = other.mPosition.m${orientation.upper()}Position;
+            layer.mPosition.${keyword} = other.mPosition.${keyword};
         }
         self.gecko.${image_layers_field}.mPosition${orientation.upper()}Count = count;
     }
@@ -3789,7 +3768,7 @@ fn static_assert() {
         longhands::${shorthand}_position_${orientation}::computed_value::List(
             self.gecko.${image_layers_field}.mLayers.iter()
                 .take(self.gecko.${image_layers_field}.mPosition${orientation.upper()}Count as usize)
-                .map(|position| position.mPosition.m${orientation.upper()}Position.into())
+                .map(|position| position.mPosition.${keyword})
                 .collect()
         )
     }
@@ -3812,7 +3791,7 @@ fn static_assert() {
         self.gecko.${image_layers_field}.mPosition${orientation[0].upper()}Count = v.len() as u32;
         for (servo, geckolayer) in v.zip(self.gecko.${image_layers_field}
                                                            .mLayers.iter_mut()) {
-            geckolayer.mPosition.m${orientation[0].upper()}Position = servo.into();
+            geckolayer.mPosition.${keyword} = servo;
         }
     }
     % endfor

components/style/values/generics/position.rs

@@ -19,20 +19,20 @@
     ToAnimatedZero,
     ToComputedValue,
 )]
-pub struct Position<H, V> {
+#[repr(C)]
+pub struct GenericPosition<H, V> {
     /// The horizontal component of position.
     pub horizontal: H,
     /// The vertical component of position.
     pub vertical: V,
 }
 
+pub use self::GenericPosition as Position;
+
 impl<H, V> Position<H, V> {
     /// Returns a new position.
     pub fn new(horizontal: H, vertical: V) -> Self {
-        Self {
-            horizontal: horizontal,
-            vertical: vertical,
-        }
+        Self { horizontal, vertical }
     }
 }