1 files changed, 11 insertions, 68 deletions

diff --git a/components/style_derive/compute_squared_distance.rs b/components/style_derive/compute_squared_distance.rs
index 46aa376319d..df02d1312cc 100644
--- a/components/style_derive/compute_squared_distance.rs
+++ b/components/style_derive/compute_squared_distance.rs
@@ -2,50 +2,30 @@
  * 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/. */
 
+use cg;
 use quote;
-use std::borrow::Cow;
 use syn;
-use synstructure;
 
 pub fn derive(input: syn::DeriveInput) -> quote::Tokens {
     let name = &input.ident;
-    let (impl_generics, ty_generics, where_clause) = input.generics.split_for_impl();
-    let mut where_clause = where_clause.clone();
-    for param in &input.generics.ty_params {
-        where_clause.predicates.push(where_predicate(syn::Ty::Path(None, param.ident.clone().into())))
-    }
+    let trait_path = &["values", "distance", "ComputeSquaredDistance"];
+    let (impl_generics, ty_generics, mut where_clause) =
+        cg::trait_parts(&input, trait_path);
 
-    let variants = variants(&input);
+    let variants = cg::variants(&input);
     let mut match_body = quote!();
     match_body.append_all(variants.iter().map(|variant| {
-        let name = match input.body {
-            syn::Body::Struct(_) => Cow::Borrowed(&input.ident),
-            syn::Body::Enum(_) => {
-                Cow::Owned(syn::Ident::from(format!("{}::{}", input.ident, variant.ident)))
-            },
-        };
-        let (this_pattern, this_info) = synstructure::match_pattern(
-            &name,
-            &variant.data,
-            &synstructure::BindOpts::with_prefix(
-                synstructure::BindStyle::Ref,
-                "this".to_owned(),
-            ),
-        );
-        let (other_pattern, other_info) = synstructure::match_pattern(
-            &name,
-            &variant.data,
-            &synstructure::BindOpts::with_prefix(
-                synstructure::BindStyle::Ref,
-                "other".to_owned(),
-            ),
-        );
+        let name = cg::variant_ctor(&input, variant);
+        let (this_pattern, this_info) = cg::ref_pattern(&name, &variant, "this");
+        let (other_pattern, other_info) = cg::ref_pattern(&name, &variant, "other");
         let sum = if this_info.is_empty() {
             quote! { ::values::distance::SquaredDistance::Value(0.) }
         } else {
             let mut sum = quote!();
             sum.append_separated(this_info.iter().zip(&other_info).map(|(this, other)| {
-                where_clause.predicates.push(where_predicate(this.field.ty.clone()));
+                where_clause.predicates.push(
+                    cg::where_predicate(this.field.ty.clone(), trait_path),
+                );
                 quote! {
                     ::values::distance::ComputeSquaredDistance::compute_squared_distance(#this, #other)?
                 }
@@ -78,40 +58,3 @@ pub fn derive(input: syn::DeriveInput) -> quote::Tokens {
         }
     }
 }
-
-fn variants(input: &syn::DeriveInput) -> Cow<[syn::Variant]> {
-    match input.body {
-        syn::Body::Enum(ref variants) => (&**variants).into(),
-        syn::Body::Struct(ref data) => {
-            vec![syn::Variant {
-                ident: input.ident.clone(),
-                attrs: input.attrs.clone(),
-                data: data.clone(),
-                discriminant: None,
-            }].into()
-        },
-    }
-}
-
-fn where_predicate(ty: syn::Ty) -> syn::WherePredicate {
-    syn::WherePredicate::BoundPredicate(
-        syn::WhereBoundPredicate {
-            bound_lifetimes: vec![],
-            bounded_ty: ty,
-            bounds: vec![syn::TyParamBound::Trait(
-                syn::PolyTraitRef {
-                    bound_lifetimes: vec![],
-                    trait_ref: syn::Path {
-                        global: true,
-                        segments: vec![
-                            "values".into(),
-                            "distance".into(),
-                            "ComputeSquaredDistance".into(),
-                        ],
-                    },
-                },
-                syn::TraitBoundModifier::None,
-            )],
-        },
-    )
-}