webidl: add support for typedefs

crates/backend/src/ast.rs

@@ -10,6 +10,7 @@ pub struct Program {
     pub imports: Vec<Import>,
     pub enums: Vec<Enum>,
     pub structs: Vec<Struct>,
+    pub type_aliases: Vec<TypeAlias>,
 }
 
 #[cfg_attr(feature = "extra-traits", derive(Debug, PartialEq, Eq))]
@@ -120,6 +121,13 @@ pub enum TypeLocation {
     ExportRet,
 }
 
+#[cfg_attr(feature = "extra-traits", derive(Debug, PartialEq, Eq))]
+pub struct TypeAlias {
+    pub vis: syn::Visibility,
+    pub dest: Ident,
+    pub src: syn::Type,
+}
+
 impl Program {
     pub fn push_item(
         &mut self,

crates/backend/src/codegen.rs

@@ -59,6 +59,9 @@ impl ToTokens for ast::Program {
         for e in self.enums.iter() {
             e.to_tokens(tokens);
         }
+        for a in self.type_aliases.iter() {
+            a.to_tokens(tokens);
+        }
 
         // Generate a static which will eventually be what lives in a custom section
         // of the wasm executable. For now it's just a plain old static, but we'll
@@ -823,3 +826,15 @@ impl ToTokens for ast::ImportStatic {
         }).to_tokens(into);
     }
 }
+
+impl ToTokens for ast::TypeAlias {
+    fn to_tokens(&self, into: &mut TokenStream) {
+        let vis = &self.vis;
+        let dest = &self.dest;
+        let src = &self.src;
+        (quote! {
+            #[allow(non_camel_case_types)]
+            #vis type #dest = #src;
+        }).to_tokens(into);
+    }
+}

crates/webidl/src/lib.rs

@@ -123,6 +123,7 @@ impl<'a> WebidlParse<'a> for webidl::ast::Definition {
             webidl::ast::Definition::Interface(ref interface) => {
                 interface.webidl_parse(program, ())
             }
+            webidl::ast::Definition::Typedef(ref typedef) => typedef.webidl_parse(program, ()),
             // TODO
             webidl::ast::Definition::Callback(..)
             | webidl::ast::Definition::Dictionary(..)
@@ -130,8 +131,7 @@ impl<'a> WebidlParse<'a> for webidl::ast::Definition {
             | webidl::ast::Definition::Implements(..)
             | webidl::ast::Definition::Includes(..)
             | webidl::ast::Definition::Mixin(..)
-            | webidl::ast::Definition::Namespace(..)
-            | webidl::ast::Definition::Typedef(..) => {
+            | webidl::ast::Definition::Namespace(..) => {
                 warn!("Unsupported WebIDL definition: {:?}", self);
                 Ok(())
             }
@@ -156,6 +156,34 @@ impl<'a> WebidlParse<'a> for webidl::ast::Interface {
     }
 }
 
+impl<'a> WebidlParse<'a> for webidl::ast::Typedef {
+    type Extra = ();
+
+    fn webidl_parse(&self, program: &mut backend::ast::Program, _: ()) -> Result<()> {
+        let dest = rust_ident(&self.name);
+        let src = match webidl_ty_to_syn_ty(&self.type_, TypePosition::Return) {
+            Some(src) => src,
+            None => {
+                warn!(
+                    "typedef's source type is not yet supported: {:?}. Skipping typedef {:?}",
+                    *self.type_, self
+                );
+                return Ok(());
+            }
+        };
+
+        program.type_aliases.push(backend::ast::TypeAlias {
+            vis: syn::Visibility::Public(syn::VisPublic {
+                pub_token: Default::default(),
+            }),
+            dest,
+            src,
+        });
+
+        Ok(())
+    }
+}
+
 impl<'a> WebidlParse<'a> for webidl::ast::NonPartialInterface {
     type Extra = ();
 

crates/webidl/tests/expected/Event.rs

@@ -224,6 +224,8 @@ impl Event {
         );
     }
 }
+#[allow(non_camel_case_types)]
+pub type DOMHighResTimeStamp = f64;
 #[allow(non_upper_case_globals)]
 #[wasm_custom_section = "__wasm_bindgen_unstable"]
 const __WASM_BINDGEN_GENERATED_wasm_bindgen_webidl_0_2_11_0 : [ u8 ; 1299usize ] = * b"\x0F\x05\0\0{\"exports\":[],\"enums\":[],\"imports\":[{\"module\":null,\"version\":null,\"js_namespace\":null,\"kind\":{\"kind\":\"type\"}},{\"module\":null,\"version\":null,\"js_namespace\":null,\"kind\":{\"kind\":\"function\",\"shim\":\"__wbg_f_stopPropagation_stop_propagation_Event\",\"catch\":false,\"method\":true,\"js_new\":false,\"structural\":false,\"getter\":null,\"setter\":null,\"class\":\"Event\",\"function\":{\"name\":\"stopPropagation\"}}},{\"module\":null,\"version\":null,\"js_namespace\":null,\"kind\":{\"kind\":\"function\",\"shim\":\"__wbg_f_stopImmediatePropagation_stop_immediate_propagation_Event\",\"catch\":false,\"method\":true,\"js_new\":false,\"structural\":false,\"getter\":null,\"setter\":null,\"class\":\"Event\",\"function\":{\"name\":\"stopImmediatePropagation\"}}},{\"module\":null,\"version\":null,\"js_namespace\":null,\"kind\":{\"kind\":\"function\",\"shim\":\"__wbg_f_preventDefault_prevent_default_Event\",\"catch\":false,\"method\":true,\"js_new\":false,\"structural\":false,\"getter\":null,\"setter\":null,\"class\":\"Event\",\"function\":{\"name\":\"preventDefault\"}}},{\"module\":null,\"version\":null,\"js_namespace\":null,\"kind\":{\"kind\":\"function\",\"shim\":\"__wbg_f_initEvent_init_event_Event\",\"catch\":false,\"method\":true,\"js_new\":false,\"structural\":false,\"getter\":null,\"setter\":null,\"class\":\"Event\",\"function\":{\"name\":\"initEvent\"}}}],\"structs\":[],\"version\":\"0.2.11 (71107b8e8)\",\"schema_version\":\"4\"}" ;

crates/webidl/tests/fixtures/Event.webidl

@@ -10,6 +10,9 @@
  * liability, trademark and document use rules apply.
  */
 
+// TODO: don't include this here, use Performance.webidl instead
+typedef double DOMHighResTimeStamp;
+
 [Constructor(DOMString type, optional EventInit eventInitDict),
  Exposed=(Window,Worker,System), ProbablyShortLivingWrapper]
 interface Event {