fix: resource shadowing cross-reference case (#340)

crates/js-component-bindgen/src/transpile_bindgen.rs

@@ -1636,28 +1636,16 @@ impl<'a> Instantiator<'a, '_> {
                     }
                 );
             }
-            FunctionKind::Constructor(ty) => {
+            FunctionKind::Constructor(_) => {
                 if self.defined_resource_classes.contains(local_name) {
                     panic!("Internal error: Resource constructor must be defined before other methods and statics");
                 }
-                let ty = &self.resolve.types[ty];
-                let name = ty.name.as_ref().unwrap();
-                if name.to_upper_camel_case() == local_name {
-                    uwrite!(
-                        self.src.js,
-                        "
-                        class {local_name} {{
-                            constructor"
-                    );
-                } else {
-                    uwrite!(
-                        self.src.js,
-                        "
-                        const {local_name} = class {} {{
-                            constructor",
-                        name.to_upper_camel_case()
-                    );
-                }
+                uwrite!(
+                    self.src.js,
+                    "
+                    class {local_name} {{
+                        constructor"
+                );
                 self.defined_resource_classes.insert(local_name.to_string());
             }
         }

crates/wasm-tools-component/src/lib.rs

@@ -1,4 +1,5 @@
 use std::collections::VecDeque;
+use std::fs::metadata;
 use std::path::PathBuf;
 use wasm_encoder::{Encode, Section};
 use wasm_metadata::Producers;
@@ -74,16 +75,20 @@ impl Guest for WasmToolsJs {
 
         let mut resolve = Resolve::default();
 
-        let pkg = if let Some(wit_source) = &embed_opts.wit_source {
+        let id = if let Some(wit_source) = &embed_opts.wit_source {
             let path = PathBuf::from("component.wit");
-            UnresolvedPackage::parse(&path, wit_source).map_err(|e| e.to_string())?
+            let pkg = UnresolvedPackage::parse(&path, wit_source).map_err(|e| e.to_string())?;
+            resolve.push(pkg).map_err(|e| e.to_string())?
         } else {
-            let wit_path = &embed_opts.wit_path.as_ref().unwrap();
-            UnresolvedPackage::parse_file(&PathBuf::from(wit_path)).map_err(|e| e.to_string())?
+            let wit_path = &PathBuf::from(embed_opts.wit_path.as_ref().unwrap());
+            if metadata(wit_path).unwrap().is_file() {
+                let pkg = UnresolvedPackage::parse_file(wit_path).map_err(|e| e.to_string())?;
+                resolve.push(pkg).map_err(|e| e.to_string())?
+            } else {
+                resolve.push_dir(wit_path).map_err(|e| e.to_string())?.0
+            }
         };
 
-        let id = resolve.push(pkg).map_err(|e| e.to_string())?;
-
         let world_string = embed_opts.world.as_ref().map(|world| world.to_string());
         let world = resolve
             .select_world(id, world_string.as_deref())

packages/preview2-shim/lib/nodejs/filesystem.js

@@ -608,6 +608,10 @@ function convertFsError(e) {
       return "unsupported";
     case "ENOTTY":
       return "no-tty";
+    // windows gives this error for badly structured `//` reads
+    // this seems like a slightly better error than unknown given
+    // that it's a common footgun
+    case -4094:
     case "ENXIO":
       return "no-such-device";
     case "EOVERFLOW":

src/cmd/transpile.js

@@ -1,19 +1,34 @@
 import { $init, generate } from '../../obj/js-component-bindgen-component.js';
-import { writeFile } from 'fs/promises';
-import { mkdir } from 'fs/promises';
-import { dirname, extname, basename } from 'path';
+import { writeFile } from 'node:fs/promises';
+import { mkdir } from 'node:fs/promises';
+import { dirname, extname, basename, resolve } from 'node:path';
 import c from 'chalk-template';
 import { readFile, sizeStr, table, spawnIOTmp, setShowSpinner, getShowSpinner } from '../common.js';
 import { optimizeComponent } from './opt.js';
 import { minify } from 'terser';
 import { fileURLToPath } from 'url';
+import { $init as wasmToolsInit, tools } from "../../obj/wasm-tools.js";
+const { componentEmbed, componentNew } = tools;
 import ora from '#ora';
+import { platform } from 'node:process';
+
+const isWindows = platform === 'win32';
 
 export async function transpile (componentPath, opts, program) {
   const varIdx = program?.parent.rawArgs.indexOf('--');
   if (varIdx !== undefined && varIdx !== -1)
     opts.optArgs = program.parent.rawArgs.slice(varIdx + 1);
-  const component = await readFile(componentPath);
+
+  let component;
+  if (!opts.stub) {
+    component = await readFile(componentPath);
+  } else {
+    await wasmToolsInit;
+    component = componentNew(componentEmbed({
+      dummy: true,
+      witPath: (isWindows ? '//?/' : '') + resolve(componentPath)
+    }), []);
+  }
 
   if (!opts.quiet)
     setShowSpinner(true);

src/cmd/wasm-tools.js

@@ -4,7 +4,6 @@ import { $init, tools } from "../../obj/wasm-tools.js";
 const { print: printFn, parse: parseFn, componentWit: componentWitFn, componentNew: componentNewFn, componentEmbed: componentEmbedFn, metadataAdd: metadataAddFn, metadataShow: metadataShowFn } = tools;
 import { resolve, basename, extname } from 'node:path';
 import c from 'chalk-template';
-import { platform } from 'node:process';
 
 export async function parse(file, opts) {
   await $init;

src/jco.js

@@ -44,6 +44,7 @@ program.command('transpile')
   .option('--no-nodejs-compat', 'disables compatibility in Node.js without a fetch global')
   .option('-M, --map <mappings...>', 'specifier=./output custom mappings for the component imports')
   .option('--no-wasi-shim', 'disable automatic rewriting of WASI imports to use @bytecodealliance/preview2-shim')
+  .option('--stub', 'generate a stub implementation from a WIT file directly')
   .option('--js', 'output JS instead of core WebAssembly')
   .addOption(new Option('-I, --instantiation [mode]', 'output for custom module instantiation').choices(['async', 'sync']).preset('async'))
   .option('-q, --quiet', 'disable logging')

test/cli.js

@@ -139,6 +139,13 @@ export async function cliTest (fixtures) {
       }
     });
 
+    test('Wit shadowing stub test', async () => {
+      const { stderr, stdout } = await exec(jcoPath, 'transpile', `test/fixtures/wit/deps/app/app.wit`, '-o', outDir, '--stub');
+      strictEqual(stderr, '');
+      const source = await readFile(`${outDir}/app.js`);
+      ok(source.includes('class PString$1{'));
+    });
+
     test('Wit & New', async () => {
       const { stderr, stdout } = await exec(jcoPath, 'wit', `test/fixtures/components/flavorful.component.wasm`);
       strictEqual(stderr, '');

test/codegen.js

@@ -62,7 +62,7 @@ export async function codegenTest (fixtures) {
 
       const bindingsSource = new TextDecoder().decode(files['resource-naming.js']);
 
-      ok(bindingsSource.includes('const Thing$1 = class Thing'));
+      ok(bindingsSource.includes('class Thing$1{'));
       ok(bindingsSource.includes('Thing: Thing$1'));
     });
   });

test/fixtures/wit/deps/app/app.wit

@@ -0,0 +1,34 @@
+package jcbhmr:hello-world-rust-wasm-component-lib;
+
+interface cbh {
+  resource p-string {
+    call: func(a: string);
+  }
+  resource r-string {
+    call: func() -> string;
+  }
+}
+interface cb {
+  use cbh.{p-string as h-p-string, r-string as h-r-string};
+  resource p-string {
+    constructor(cb: h-p-string);
+    call: func(a: string);
+  }
+  resource r-string {
+    constructor(cb: h-r-string);
+    call: func() -> string;
+  }
+}
+
+interface hello-world {
+  use cb.{p-string, r-string};
+  set-cb: func(cb: p-string);
+  run-cb-with-result-of: func(cb: borrow<r-string>);
+}
+
+world hello-world-rust-wasm-component-lib {
+  import cbh;
+  export cb;
+
+  export hello-world;
+}