Use the JS name of an imported type for instanceof checks

crates/backend/src/ast.rs

@@ -125,6 +125,7 @@ pub struct ImportStatic {
 pub struct ImportType {
     pub vis: syn::Visibility,
     pub rust_name: Ident,
+    pub js_name: String,
     pub attrs: Vec<syn::Attribute>,
     pub doc_comment: Option<String>,
     pub instanceof_shim: String,
@@ -411,7 +412,7 @@ impl ImportStatic {
 impl ImportType {
     fn shared(&self) -> shared::ImportType {
         shared::ImportType {
-            name: self.rust_name.to_string(),
+            name: self.js_name.clone(),
             instanceof_shim: self.instanceof_shim.clone(),
         }
     }

crates/macro-support/src/parser.rs

@@ -542,6 +542,9 @@ impl ConvertToAst<BindgenAttrs> for syn::ForeignItemType {
     type Target = ast::ImportKind;
 
     fn convert(self, attrs: BindgenAttrs) -> Result<Self::Target, Diagnostic> {
+        let js_name = attrs
+            .js_name()
+            .map_or_else(|| self.ident.to_string(), |s| s.to_string());
         let shim = format!("__wbg_instanceof_{}_{}", self.ident, ShortHash(&self.ident));
         Ok(ast::ImportKind::Type(ast::ImportType {
             vis: self.vis,
@@ -549,6 +552,7 @@ impl ConvertToAst<BindgenAttrs> for syn::ForeignItemType {
             doc_comment: None,
             instanceof_shim: shim,
             rust_name: self.ident,
+            js_name,
             extends: attrs.extends().cloned().collect(),
         }))
     }

crates/web-sys/tests/wasm/html_element.rs

@@ -1,5 +1,6 @@
 use wasm_bindgen_test::*;
 use wasm_bindgen::prelude::*;
+use wasm_bindgen::JsCast;
 use web_sys::HtmlElement;
 
 #[wasm_bindgen(module = "./tests/wasm/element.js")]
@@ -10,6 +11,8 @@ extern {
 #[wasm_bindgen_test]
 fn test_html_element() {
     let element = new_html();
+    assert!(element.is_instance_of::<HtmlElement>());
+
     assert_eq!(element.title(), "", "Shouldn't have a title");
     element.set_title("boop");
     assert_eq!(element.title(), "boop", "Should have a title");

crates/webidl/src/lib.rs

@@ -244,7 +244,8 @@ impl<'src> WebidlParse<'src, ()> for weedle::InterfaceDefinition<'src> {
             js_namespace: None,
             kind: backend::ast::ImportKind::Type(backend::ast::ImportType {
                 vis: public(),
-                name: rust_ident(camel_case_ident(self.identifier.0).as_str()),
+                rust_name: rust_ident(camel_case_ident(self.identifier.0).as_str()),
+                js_name: self.identifier.0.to_string(),
                 attrs: Vec::new(),
                 doc_comment,
                 instanceof_shim: format!("__widl_instanceof_{}", self.identifier.0),

tests/wasm/simple.js

@@ -87,3 +87,6 @@ exports.test_rust_optional = function() {
   assert.strictEqual(wasm.return_optional_str_none(), undefined);
   assert.strictEqual(wasm.return_optional_str_some(), 'world');
 };
+
+exports.RenamedInRust = class {};
+exports.new_renamed = () => new exports.RenamedInRust;

tests/wasm/simple.rs

@@ -1,5 +1,6 @@
 use wasm_bindgen_test::*;
 use wasm_bindgen::prelude::*;
+use wasm_bindgen::JsCast;
 
 #[wasm_bindgen(module = "tests/wasm/simple.js")]
 extern {
@@ -20,6 +21,10 @@ extern {
     fn return_string_none() -> Option<String>;
     fn return_string_some() -> Option<String>;
     fn test_rust_optional();
+
+    #[wasm_bindgen(js_name = RenamedInRust)]
+    type Renamed;
+    fn new_renamed() -> Renamed;
 }
 
 #[wasm_bindgen_test]
@@ -178,3 +183,15 @@ pub fn return_optional_str_none() -> Option<String> {
 pub fn return_optional_str_some() -> Option<String> {
     Some("world".to_string())
 }
+
+#[wasm_bindgen_test]
+fn renaming_imports_and_instanceof() {
+    let null = JsValue::NULL;
+    assert!(!null.is_instance_of::<Renamed>());
+
+    let arr: JsValue = Array::new().into();
+    assert!(!arr.is_instance_of::<Renamed>());
+
+    let renamed: JsValue = new_renamed().into();
+    assert!(renamed.is_instance_of::<Renamed>());
+}