Create a module for generics and make BorderRadiusSize generic

components/style/values/generics/mod.rs

@@ -0,0 +1,65 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+//! Generic types that share their serialization implementations
+//! for both specified and computed values.
+
+use euclid::size::Size2D;
+use std::fmt;
+use style_traits::ToCss;
+use super::HasViewportPercentage;
+use super::computed::{Context, ToComputedValue};
+
+#[derive(Clone, PartialEq, Debug)]
+#[cfg_attr(feature = "servo", derive(HeapSizeOf))]
+/// A type for representing CSS `widthh` and `height` values.
+pub struct BorderRadiusSize<L>(pub Size2D<L>);
+
+impl<L> HasViewportPercentage for BorderRadiusSize<L> {
+    #[inline]
+    fn has_viewport_percentage(&self) -> bool { false }
+}
+
+impl<L> BorderRadiusSize<L> {
+    #[inline]
+    /// Create a new `BorderRadiusSize` for an area of given width and height.
+    pub fn new(width: L, height: L) -> BorderRadiusSize<L> {
+        BorderRadiusSize(Size2D::new(width, height))
+    }
+}
+
+impl<L: Clone> BorderRadiusSize<L> {
+    #[inline]
+    /// Create a new `BorderRadiusSize` for a circle of given radius.
+    pub fn circle(radius: L) -> BorderRadiusSize<L> {
+        BorderRadiusSize(Size2D::new(radius.clone(), radius))
+    }
+}
+
+impl<L: ToCss> ToCss for BorderRadiusSize<L> {
+    #[inline]
+    fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
+        self.0.width.to_css(dest)?;
+        dest.write_str(" ")?;
+        self.0.height.to_css(dest)
+    }
+}
+
+impl<L: ToComputedValue> ToComputedValue for BorderRadiusSize<L> {
+    type ComputedValue = BorderRadiusSize<L::ComputedValue>;
+
+    #[inline]
+    fn to_computed_value(&self, context: &Context) -> Self::ComputedValue {
+        let w = self.0.width.to_computed_value(context);
+        let h = self.0.height.to_computed_value(context);
+        BorderRadiusSize(Size2D::new(w, h))
+    }
+
+    #[inline]
+    fn from_computed_value(computed: &Self::ComputedValue) -> Self {
+        let w = ToComputedValue::from_computed_value(&computed.0.width);
+        let h = ToComputedValue::from_computed_value(&computed.0.height);
+        BorderRadiusSize(Size2D::new(w, h))
+    }
+}