Allow web-sys to emit correct typescript declarations from webidl (#1998)

* Update to emit typescript names

* Update to use NamedAnyref

* Update incoming / outgoing

* Remove added space

* Remove comment

* Add basic typescript tests for web-sys

crates/backend/src/ast.rs

@@ -181,6 +181,7 @@ pub struct ImportType {
     pub rust_name: Ident,
     pub js_name: String,
     pub attrs: Vec<syn::Attribute>,
+    pub typescript_name: Option<String>,
     pub doc_comment: Option<String>,
     pub instanceof_shim: String,
     pub is_type_of: Option<syn::Expr>,

crates/backend/src/codegen.rs

@@ -579,6 +579,21 @@ impl ToTokens for ast::ImportType {
             }
         };
 
+        let description = if let Some(typescript_name) = &self.typescript_name {
+            let typescript_name_len = typescript_name.len() as u32;
+            let typescript_name_chars = typescript_name.chars().map(|c| c as u32);
+            quote! {
+                use wasm_bindgen::describe::*;
+                inform(NAMED_ANYREF);
+                inform(#typescript_name_len);
+                #(inform(#typescript_name_chars);)*
+            }
+        } else {
+            quote! {
+                JsValue::describe()
+            }
+        };
+
         let is_type_of = self.is_type_of.as_ref().map(|is_type_of| {
             quote! {
                 #[inline]
@@ -611,7 +626,7 @@ impl ToTokens for ast::ImportType {
 
                 impl WasmDescribe for #rust_name {
                     fn describe() {
-                        JsValue::describe();
+                        #description
                     }
                 }
 

crates/cli-support/src/descriptor.rs

@@ -31,6 +31,7 @@ tys! {
     SLICE
     VECTOR
     ANYREF
+    NAMED_ANYREF
     ENUM
     RUST_STRUCT
     CHAR
@@ -62,6 +63,7 @@ pub enum Descriptor {
     CachedString,
     String,
     Anyref,
+    NamedAnyref(String),
     Enum { hole: u32 },
     RustStruct(String),
     Char,
@@ -134,11 +136,13 @@ impl Descriptor {
             ANYREF => Descriptor::Anyref,
             ENUM => Descriptor::Enum { hole: get(data) },
             RUST_STRUCT => {
-                let name = (0..get(data))
+                let name = get_string(data);
-                    .map(|_| char::from_u32(get(data)).unwrap())
-                    .collect();
                 Descriptor::RustStruct(name)
             }
+            NAMED_ANYREF => {
+                let name = get_string(data);
+                Descriptor::NamedAnyref(name)
+            }
             CHAR => Descriptor::Char,
             UNIT => Descriptor::Unit,
             CLAMPED => Descriptor::_decode(data, true),
@@ -200,6 +204,12 @@ fn get(a: &mut &[u32]) -> u32 {
     ret
 }
 
+fn get_string(data: &mut &[u32]) -> String {
+    (0..get(data))
+        .map(|_| char::from_u32(get(data)).unwrap())
+        .collect()
+}
+
 impl Closure {
     fn decode(data: &mut &[u32]) -> Closure {
         let shim_idx = get(data);

crates/cli-support/src/js/binding.rs

@@ -1238,6 +1238,7 @@ fn adapter2ts(ty: &AdapterType, dst: &mut String) {
             adapter2ts(ty, dst);
             dst.push_str(" | undefined");
         }
+        AdapterType::NamedAnyref(name) => dst.push_str(name),
         AdapterType::Struct(name) => dst.push_str(name),
         AdapterType::Function => dst.push_str("any"),
     }

crates/cli-support/src/wit/incoming.rs

@@ -67,6 +67,13 @@ impl InstructionBuilder<'_, '_> {
                     &[AdapterType::I32],
                 );
             }
+            Descriptor::NamedAnyref(name) => {
+                self.instruction(
+                    &[AdapterType::NamedAnyref(name.clone())],
+                    Instruction::I32FromAnyrefOwned,
+                    &[AdapterType::I32]
+                )
+            }
             Descriptor::RustStruct(class) => {
                 self.instruction(
                     &[AdapterType::Struct(class.clone())],
@@ -161,6 +168,13 @@ impl InstructionBuilder<'_, '_> {
                     &[AdapterType::I32],
                 );
             }
+            Descriptor::NamedAnyref(name) => {
+                self.instruction(
+                    &[AdapterType::NamedAnyref(name.clone())],
+                    Instruction::I32FromAnyrefBorrow,
+                    &[AdapterType::I32],
+                );
+            }
             Descriptor::String | Descriptor::CachedString => {
                 // This allocation is cleaned up once it's received in Rust.
                 self.instruction(
@@ -224,6 +238,15 @@ impl InstructionBuilder<'_, '_> {
                     &[AdapterType::I32],
                 );
             }
+            Descriptor::NamedAnyref(name) => {
+                self.instruction(
+                    &[AdapterType::NamedAnyref(name.clone()).option()],
+                    Instruction::I32FromOptionAnyref {
+                        table_and_alloc: None,
+                    },
+                    &[AdapterType::I32],
+                );
+            }
             Descriptor::I8 => self.in_option_sentinel(AdapterType::S8),
             Descriptor::U8 => self.in_option_sentinel(AdapterType::U8),
             Descriptor::I16 => self.in_option_sentinel(AdapterType::S16),

crates/cli-support/src/wit/outgoing.rs

@@ -39,6 +39,13 @@ impl InstructionBuilder<'_, '_> {
                     &[AdapterType::Anyref],
                 );
             }
+            Descriptor::NamedAnyref(name) => {
+                self.instruction(
+                    &[AdapterType::I32],
+                    Instruction::AnyrefLoadOwned,
+                    &[AdapterType::NamedAnyref(name.clone())],
+                );
+            }
             Descriptor::I8 => self.outgoing_i32(AdapterType::S8),
             Descriptor::U8 => self.outgoing_i32(AdapterType::U8),
             Descriptor::I16 => self.outgoing_i32(AdapterType::S16),
@@ -162,6 +169,13 @@ impl InstructionBuilder<'_, '_> {
                     &[AdapterType::Anyref],
                 );
             }
+            Descriptor::NamedAnyref(name) => {
+                self.instruction(
+                    &[AdapterType::I32],
+                    Instruction::TableGet,
+                    &[AdapterType::NamedAnyref(name.clone())],
+                );
+            }
             Descriptor::CachedString => self.cached_string(false, false)?,
 
             Descriptor::String => {
@@ -227,6 +241,13 @@ impl InstructionBuilder<'_, '_> {
                     &[AdapterType::Anyref.option()],
                 );
             }
+            Descriptor::NamedAnyref(name) => {
+                self.instruction(
+                    &[AdapterType::I32],
+                    Instruction::AnyrefLoadOwned,
+                    &[AdapterType::NamedAnyref(name.clone()).option()],
+                );
+            }
             Descriptor::I8 => self.out_option_sentinel(AdapterType::S8),
             Descriptor::U8 => self.out_option_sentinel(AdapterType::U8),
             Descriptor::I16 => self.out_option_sentinel(AdapterType::S16),
@@ -316,6 +337,13 @@ impl InstructionBuilder<'_, '_> {
                     &[AdapterType::Anyref.option()],
                 );
             }
+            Descriptor::NamedAnyref(name) => {
+                self.instruction(
+                    &[AdapterType::I32],
+                    Instruction::TableGet,
+                    &[AdapterType::NamedAnyref(name.clone()).option()],
+                );
+            }
             Descriptor::CachedString => self.cached_string(true, false)?,
             Descriptor::String | Descriptor::Slice(_) => {
                 let kind = arg.vector_kind().ok_or_else(|| {

crates/cli-support/src/wit/standard.rs

@@ -84,6 +84,7 @@ pub enum AdapterType {
     Vector(VectorKind),
     Option(Box<AdapterType>),
     Struct(String),
+    NamedAnyref(String),
     Function,
 }
 
@@ -322,7 +323,7 @@ impl AdapterType {
             AdapterType::I64 => walrus::ValType::I64,
             AdapterType::F32 => walrus::ValType::F32,
             AdapterType::F64 => walrus::ValType::F64,
-            AdapterType::Anyref => walrus::ValType::Anyref,
+            AdapterType::Anyref | AdapterType::NamedAnyref(_) => walrus::ValType::Anyref,
             _ => return None,
         })
     }
@@ -340,7 +341,7 @@ impl AdapterType {
             AdapterType::F32 => wit_walrus::ValType::F32,
             AdapterType::F64 => wit_walrus::ValType::F64,
             AdapterType::String => wit_walrus::ValType::String,
-            AdapterType::Anyref => wit_walrus::ValType::Anyref,
+            AdapterType::Anyref | AdapterType::NamedAnyref(_) => wit_walrus::ValType::Anyref,
 
             AdapterType::I32 => wit_walrus::ValType::I32,
             AdapterType::I64 => wit_walrus::ValType::I64,

crates/macro-support/src/parser.rs

@@ -554,6 +554,7 @@ impl ConvertToAst<BindgenAttrs> for syn::ForeignItemType {
             instanceof_shim: shim,
             is_type_of,
             rust_name: self.ident,
+            typescript_name: None,
             js_name,
             extends,
             vendor_prefixes,

crates/typescript-tests/Cargo.toml

@@ -6,6 +6,7 @@ edition = "2018"
 
 [dependencies]
 wasm-bindgen = { path = '../..' }
+web-sys = { path = '../web-sys', features = [ 'HtmlElement', 'Node', 'Document' ] }
 
 [lib]
 crate-type = ['cdylib']

crates/typescript-tests/src/lib.rs

@@ -4,3 +4,4 @@ pub mod opt_args_and_ret;
 pub mod optional_fields;
 pub mod simple_fn;
 pub mod simple_struct;
+pub mod web_sys;

crates/typescript-tests/src/web_sys.rs

@@ -0,0 +1,24 @@
+use wasm_bindgen::prelude::*;
+use web_sys::*;
+
+#[wasm_bindgen]
+pub struct DocStruct {
+    doc: Document,
+}
+
+#[wasm_bindgen]
+impl DocStruct {
+    pub fn new(doc: Document) -> Self {
+        Self { doc }
+    }
+
+    pub fn get_doc(&self) -> Document {
+        self.doc.clone()
+    }
+
+    pub fn append_element(&self, element: &HtmlElement) {
+        self.doc.body().unwrap().append_child(element).unwrap();
+    }
+
+    pub fn append_many(&self, _: &HtmlElement, _: &HtmlElement, _: &HtmlElement) {}
+}

crates/typescript-tests/src/web_sys.ts

@@ -0,0 +1,26 @@
+import * as wbg from "../pkg/typescript_tests";
+
+const doc: Document = document;
+
+const docStruct = wbg.DocStruct.new(doc);
+
+const el: HTMLElement = document.createElement("a");
+
+docStruct.append_element(el);
+docStruct.append_many(el, el, el);
+
+const newDoc = docStruct.get_doc();
+
+// This test ensures that the correct Typescript types are
+// used. If "newDoc" is "any", then "event" will cause the
+// compilation to fail because of noImplicitAny.
+newDoc.addEventListener("load", event => {
+  console.log(event);
+});
+
+// Same as above, but testing that the param is a document.
+const listener: Parameters<
+  Parameters<typeof wbg["DocStruct"]["new"]>[0]["addEventListener"]
+>[1] = event => console.log(event);
+
+newDoc.addEventListener("load", listener);

crates/webidl/src/lib.rs

@@ -568,6 +568,7 @@ impl<'src> FirstPassRecord<'src> {
             } else {
                 Some(syn::parse_quote! { |_| false })
             },
+            typescript_name: Some(name.to_string()),
             extends: Vec::new(),
             vendor_prefixes: Vec::new(),
         };

src/describe.rs

@@ -37,6 +37,7 @@ tys! {
     SLICE
     VECTOR
     ANYREF
+    NAMED_ANYREF
     ENUM
     RUST_STRUCT
     CHAR