From 76df67fc7bb33686bfa769f9b194b9d585ed3cee Mon Sep 17 00:00:00 2001
From: Ravi Shankar <wafflespeanut@gmail.com>
Date: Thu, 13 Apr 2017 10:59:55 +0530
Subject: [PATCH] Add add_impls_for_keyword_enum macro for implementing
 necessary traits

---
 components/style/values/mod.rs                | 21 +++++++++++++++++++
 .../style/values/specified/basic_shape.rs     |  3 ++-
 2 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/components/style/values/mod.rs b/components/style/values/mod.rs
index f3dd7089830..256d07dd733 100644
--- a/components/style/values/mod.rs
+++ b/components/style/values/mod.rs
@@ -60,6 +60,27 @@ macro_rules! no_viewport_percentage {
     };
 }
 
+/// A macro for implementing `ComputedValueAsSpecified`, `Parse`
+/// and `HasViewportPercentage` traits for the enums defined
+/// using `define_css_keyword_enum` macro.
+///
+/// NOTE: We should either move `Parse` trait to `style_traits`
+/// or `define_css_keyword_enum` macro to this crate, but that
+/// may involve significant cleanup in both the crates.
+macro_rules! add_impls_for_keyword_enum {
+    ($name:ident) => {
+        impl Parse for $name {
+            #[inline]
+            fn parse(_context: &ParserContext, input: &mut ::cssparser::Parser) -> Result<Self, ()> {
+                $name::parse(input)
+            }
+        }
+
+        impl ComputedValueAsSpecified for $name {}
+        no_viewport_percentage!($name);
+    };
+}
+
 pub mod computed;
 pub mod specified;
 
diff --git a/components/style/values/specified/basic_shape.rs b/components/style/values/specified/basic_shape.rs
index a4f302b0df1..311049043e0 100644
--- a/components/style/values/specified/basic_shape.rs
+++ b/components/style/values/specified/basic_shape.rs
@@ -14,6 +14,7 @@ use properties::shorthands::{parse_four_sides, serialize_four_sides};
 use std::ascii::AsciiExt;
 use std::fmt;
 use style_traits::ToCss;
+use values::HasViewportPercentage;
 use values::computed::{ComputedValueAsSpecified, Context, ToComputedValue};
 use values::computed::basic_shape as computed_basic_shape;
 use values::specified::{BorderRadiusSize, LengthOrPercentage, Percentage};
@@ -861,4 +862,4 @@ define_css_keyword_enum!(ShapeBox:
     "content-box" => ContentBox
 );
 
-impl ComputedValueAsSpecified for ShapeBox {}
+add_impls_for_keyword_enum!(ShapeBox);