Add a ascii_case_insensitive_phf_map macro, use it for color keywords.

Fix #115.

Author: SimonSapin

Cargo.toml

@@ -26,6 +26,7 @@ encoding_rs = "0.5"
 cssparser-macros = {path = "./macros", version = "0.1"}
 heapsize = {version = "0.3", optional = true}
 matches = "0.1"
+phf = "0.7"
 serde = {version = "0.9", optional = true}
 
 [build-dependencies]

macros/Cargo.toml

@@ -12,5 +12,7 @@ path = "lib.rs"
 proc-macro = true
 
 [dependencies]
-syn = "0.11"
+phf_codegen = "0.7"
 quote = "0.3"
+syn = "0.11"
+

macros/lib.rs

@@ -2,46 +2,96 @@
  * 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/. */
 
+extern crate phf_codegen;
 extern crate proc_macro;
 #[macro_use] extern crate quote;
 extern crate syn;
 
 use std::ascii::AsciiExt;
 
-#[proc_macro_derive(cssparser__match_ignore_ascii_case__derive,
+#[proc_macro_derive(cssparser__match_ignore_ascii_case__max_len,
                     attributes(cssparser__match_ignore_ascii_case__data))]
-pub fn expand_token_stream(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
+pub fn max_len(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
     let input = syn::parse_macro_input(&input.to_string()).unwrap();
+    let data = list_attr(&input, "cssparser__match_ignore_ascii_case__data");
 
-    let max_length;
+    let lengths = data.iter().map(|sub_attr| {
+        let string = sub_attr_value(sub_attr, "string");
+        assert_eq!(*string, string.to_ascii_lowercase(),
+                   "the expected strings must be given in ASCII lowercase");
+        string.len()
+    });
+    let max_length = lengths.max().expect("expected at least one string");
 
-    match input.attrs[0].value {
-        syn::MetaItem::List(ref ident, ref nested)
-        if ident == "cssparser__match_ignore_ascii_case__data" => {
-            let lengths = nested.iter().map(|sub_attr| match *sub_attr {
-                syn::NestedMetaItem::MetaItem(
-                    syn::MetaItem::NameValue(ref ident, syn::Lit::Str(ref string, _))
-                )
-                if ident == "string" => {
-                    assert_eq!(*string, string.to_ascii_lowercase(),
-                               "the expected strings must be given in ASCII lowercase");
-                    string.len()
-                }
-                _ => {
-                    panic!("expected a `string = \"…\" parameter to the attribute, got {:?}", sub_attr)
-                }
-            });
-
-            max_length = lengths.max().expect("expected at least one string")
-        }
-        _ => {
-            panic!("expected a cssparser_match_ignore_ascii_case_data attribute")
+    let tokens = quote! {
+        const MAX_LENGTH: usize = #max_length;
+    };
+
+    tokens.as_str().parse().unwrap()
+}
+
+
+#[proc_macro_derive(cssparser__phf_map,
+                    attributes(cssparser__phf_map__kv_pairs))]
+pub fn phf_map(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
+    let input = syn::parse_macro_input(&input.to_string()).unwrap();
+    let name = &input.ident;
+    let value_type = match input.body {
+        syn::Body::Struct(syn::VariantData::Tuple(ref fields)) if fields.len() == 1 => {
+            &fields[0].ty
         }
+        _ => panic!("expected tuple struct newtype, got {:?}", input.body)
+    };
+
+    let kv_pairs = list_attr(&input, "cssparser__phf_map__kv_pairs");
+
+    let mut map = phf_codegen::Map::new();
+    for chunk in kv_pairs.chunks(2) {
+        let key = sub_attr_value(&chunk[0], "key");
+        let value = sub_attr_value(&chunk[1], "value");
+        map.entry(key, value);
     }
 
+    let mut initializer_bytes = Vec::<u8>::new();
+    let mut initializer_tokens = quote::Tokens::new();
+    map.build(&mut initializer_bytes).unwrap();
+    initializer_tokens.append(::std::str::from_utf8(&initializer_bytes).unwrap());
+
     let tokens = quote! {
-        const MAX_LENGTH: usize = #max_length;
+        impl #name {
+            #[inline]
+            fn map() -> &'static ::phf::Map<&'static str, #value_type> {
+                static MAP: ::phf::Map<&'static str, #value_type> = #initializer_tokens;
+                &MAP
+            }
+        }
     };
 
     tokens.as_str().parse().unwrap()
 }
+
+fn list_attr<'a>(input: &'a syn::DeriveInput, expected_name: &str) -> &'a [syn::NestedMetaItem] {
+    match input.attrs[0].value {
+        syn::MetaItem::List(ref name, ref nested) if name == expected_name => {
+            nested
+        }
+        _ => {
+            panic!("expected a {} attribute", expected_name)
+        }
+    }
+}
+
+fn sub_attr_value<'a>(sub_attr: &'a syn::NestedMetaItem, expected_name: &str) -> &'a str {
+    match *sub_attr {
+        syn::NestedMetaItem::MetaItem(
+            syn::MetaItem::NameValue(ref name, syn::Lit::Str(ref value, _))
+        )
+        if name == expected_name => {
+            value
+        }
+        _ => {
+            panic!("expected a `{} = \"…\"` parameter to the attribute, got {:?}",
+                   expected_name, sub_attr)
+        }
+    }
+}