Send stdout/stderr from WasmRunner to dev server without decoding as UTF-8 (#471)

* Enable WasmRunner to handle stdout as raw binary

* catch other errors

* move devDeps

* use browser exception handling

* comment out

Tests/Fixtures/SandboxApp/.gitignore

@@ -0,0 +1,7 @@
+.DS_Store
+/.build
+/Packages
+xcuserdata/
+DerivedData/
+.swiftpm
+.netrc

Tests/Fixtures/SandboxApp/Package.swift

@@ -0,0 +1,28 @@
+// swift-tools-version: 5.9
+
+import PackageDescription
+
+let package = Package(
+  name: "DevServerTestApp",
+  products: [
+    .executable(name: "app", targets: ["app"])
+  ],
+  dependencies: [
+    .package(path: "../../.."),
+    .package(url: "https://github.com/swiftwasm/JavaScriptKit", from: "0.19.2")
+  ],
+  targets: [
+    .executableTarget(
+      name: "app",
+      dependencies: [
+        .product(name: "JavaScriptKit", package: "JavaScriptKit")
+      ],
+      resources: [
+        .copy("style.css")
+      ]
+    ),
+    .testTarget(
+        name: "SimpleTests"
+    )
+  ]
+)

Tests/Fixtures/SandboxApp/README.md

@@ -0,0 +1,4 @@
+This application serves as a working environment for experimenting with the behavior of "carton".
+Since it is not used by automated tests, it can be easily modified.
+If you want to include the behavior created here in automated tests,
+please separate the target application for testing.

Tests/Fixtures/SandboxApp/Sources/app/main.swift

@@ -0,0 +1,33 @@
+#if os(WASI)
+import WASILibc
+typealias FILEPointer = OpaquePointer
+#else
+import Darwin
+typealias FILEPointer = UnsafeMutablePointer<FILE>
+#endif
+
+import JavaScriptKit
+
+func fputs(_ string: String, file: FILEPointer) {
+    _ = string.withCString { (cstr) in
+        fputs(cstr, file)
+    }
+}
+
+fputs("hello stdout\n", file: stdout)
+fputs("hello stderr\n", file: stderr)
+
+//fatalError("hello fatalError")
+
+let document = JSObject.global.document
+
+let button = document.createElement("button")
+_ = button.appendChild(
+  document.createTextNode("click to crash")
+)
+
+_ = button.addEventListener("click", JSClosure { (e) in
+  fatalError("crash")
+})
+
+_ = document.body.appendChild(button)

Tests/Fixtures/SandboxApp/Sources/app/style.css

@@ -0,0 +1,4 @@
+* {
+  margin: 0;
+  padding: 0;
+}

Tests/Fixtures/SandboxApp/Tests/SimpleTests/BasicTests.swift

@@ -0,0 +1,7 @@
+import XCTest
+
+final class BasicTests: XCTestCase {
+  func testAdd() {
+    XCTAssertEqual(1 + 1, 2)
+  }
+}

entrypoint/bundle.ts

@@ -31,22 +31,22 @@ const startWasiTask = async () => {
     // JavaScriptKit module not available, running without JavaScriptKit runtime.
   }
 
-  const wasmRunner = WasmRunner(false, runtimeConstructor);
+  const wasmRunner = WasmRunner({
+    onStdoutLine(line) {
+      console.log(line);
+    },
+    onStderrLine(line) {
+      console.error(line);
+    }
+  }, runtimeConstructor);
 
   // Instantiate the WebAssembly file
   const wasmBytes = new Uint8Array(responseArrayBuffer).buffer;
   await wasmRunner.run(wasmBytes);
 };
 
-function handleError(e: any) {
+async function main(): Promise<void> {
-  console.error(e);
+  await startWasiTask();
-  if (e instanceof WebAssembly.RuntimeError) {
-    console.log(e.stack);
-  }
 }
 
-try {
+main();
-  startWasiTask().catch(handleError);
-} catch (e) {
-  handleError(e);
-}

entrypoint/common.ts

@@ -15,17 +15,42 @@
 import { WASI, File, OpenFile, ConsoleStdout, PreopenDirectory } from "@bjorn3/browser_wasi_shim";
 import type { SwiftRuntime, SwiftRuntimeConstructor } from "./JavaScriptKit_JavaScriptKit.resources/Runtime";
 
+export class LineDecoder {
+  constructor(onLine: (line: string) => void) {
+    this.decoder = new TextDecoder("utf-8", { fatal: false });
+    this.buffer = "";
+    this.onLine = onLine;
+  }
+
+  private decoder: TextDecoder;
+  private buffer: string;
+  private onLine: (line: string) => void;
+
+  send(chunk: Uint8Array) {
+    this.buffer += this.decoder.decode(chunk, { stream: true });
+
+    const lines = this.buffer.split("\n");
+    for (let i = 0; i < lines.length - 1; i++) {
+      this.onLine(lines[i]);
+    }
+
+    this.buffer = lines[lines.length - 1];
+  }
+}
+
 export type Options = {
   args?: string[];
-  onStdout?: (text: string) => void;
+  onStdout?: (chunk: Uint8Array) => void;
-  onStderr?: (text: string) => void;
+  onStdoutLine?: (line: string) => void;
+  onStderr?: (chunk: Uint8Array) => void;
+  onStderrLine?: (line: string) => void;
 };
 
 export type WasmRunner = {
   run(wasmBytes: ArrayBufferLike, extraWasmImports?: WebAssembly.Imports): Promise<void>
 };
 
-export const WasmRunner = (rawOptions: Options | false, SwiftRuntime: SwiftRuntimeConstructor | undefined): WasmRunner => {
+export const WasmRunner = (rawOptions: Options, SwiftRuntime: SwiftRuntimeConstructor | undefined): WasmRunner => {
   const options: Options = defaultRunnerOptions(rawOptions);
 
   let swift: SwiftRuntime;
@@ -33,17 +58,29 @@ export const WasmRunner = (rawOptions: Options | false, SwiftRuntime: SwiftRunti
     swift = new SwiftRuntime();
   }
 
+  let stdoutLine: LineDecoder | undefined = undefined;
+  if (options.onStdoutLine != null) {
+    stdoutLine = new LineDecoder(options.onStdoutLine);
+  }
+  const stdout = new ConsoleStdout((chunk) => {
+    options.onStdout?.call(undefined, chunk);
+    stdoutLine?.send(chunk);
+  });
+
+  let stderrLine: LineDecoder | undefined = undefined;
+  if (options.onStderrLine != null) {
+    stderrLine = new LineDecoder(options.onStderrLine);
+  }
+  const stderr = new ConsoleStdout((chunk) => {
+    options.onStderr?.call(undefined, chunk);
+    stderrLine?.send(chunk);
+  });
+
   const args = options.args || [];
   const fds = [
     new OpenFile(new File([])), // stdin
-    ConsoleStdout.lineBuffered((stdout) => {
+    stdout,
-      console.log(stdout);
+    stderr,
-      options.onStdout?.call(undefined, stdout);
-    }),
-    ConsoleStdout.lineBuffered((stderr) => {
-      console.error(stderr);
-      options.onStderr?.call(undefined, stderr);
-    }),
     new PreopenDirectory("/", new Map()),
   ];
 
@@ -129,15 +166,8 @@ export const WasmRunner = (rawOptions: Options | false, SwiftRuntime: SwiftRunti
   };
 };
 
-const defaultRunnerOptions = (options: Options | false): Options => {
+const defaultRunnerOptions = (options: Options): Options => {
-  if (!options) return defaultRunnerOptions({});
+  if (options.args != null) {
-  if (!options.onStdout) {
-    options.onStdout = () => { };
-  }
-  if (!options.onStderr) {
-    options.onStderr = () => { };
-  }
-  if (!options.args) {
     options.args = ["main.wasm"];
   }
   return options;

entrypoint/dev.ts

@@ -44,17 +44,12 @@ const startWasiTask = async () => {
 
   const wasmRunner = WasmRunner(
     {
-      onStderr() {
+      onStdoutLine(line) {
-        const prevLimit = Error.stackTraceLimit;
+        console.log(line);
-        Error.stackTraceLimit = 1000;
-        socket.send(
-          JSON.stringify({
-            kind: "stackTrace",
-            stackTrace: new Error().stack,
-          })
-        );
-        Error.stackTraceLimit = prevLimit;
       },
+      onStderrLine(line) {
+        console.error(line);
+      }
     },
     runtimeConstructor
   );
@@ -65,14 +60,32 @@ const startWasiTask = async () => {
 };
 
 function handleError(e: any) {
-  console.error(e);
+  if (e instanceof Error) {
-  if (e instanceof WebAssembly.RuntimeError) {
+    const stack = e.stack;
-    console.log(e.stack);
+    if (stack != null) {
+      socket.send(
+        JSON.stringify({
+          kind: "stackTrace",
+          stackTrace: stack,
+        })
+      );
+    }
   }
 }
 
-try {
+async function main(): Promise<void> {
-  startWasiTask().catch(handleError);
+  try {
-} catch (e) {
+    window.addEventListener("error", (event) => {
-  handleError(e);
+      handleError(event.error);
+    });
+    window.addEventListener("unhandledrejection", (event) => {
+      handleError(event.reason);
+    });
+    await startWasiTask();
+  } catch (e) {
+    handleError(e);
+    throw e;
+  }
 }
+
+main();

entrypoint/test.ts

@@ -45,16 +45,12 @@ const startWasiTask = async () => {
   let testRunOutput = "";
   const wasmRunner = WasmRunner(
     {
-      onStdout: (text) => {
+      onStdoutLine: (line) => {
-        testRunOutput += text + "\n";
+        console.log(line);
+        testRunOutput += line + "\n";
       },
-      onStderr: () => {
+      onStderrLine: (line) => {
-        socket.send(
+        console.error(line);
-          JSON.stringify({
-            kind: "stackTrace",
-            stackTrace: new Error().stack,
-          })
-        );
       },
     },
     runtimeConstructor
@@ -109,14 +105,33 @@ const startWasiTask = async () => {
 
 function handleError(e: any) {
   console.error(e);
-  if (e instanceof WebAssembly.RuntimeError) {
+
-    console.log(e.stack);
+  if (e instanceof Error) {
+    const stack = e.stack;
+    if (stack != null) {
+      socket.send(
+        JSON.stringify({
+          kind: "stackTrace",
+          stackTrace: stack,
+        })
+      );
+    }
   }
-  socket.send(JSON.stringify({ kind: "errorReport", errorReport: e.toString() }));
+
+  socket.send(
+    JSON.stringify({
+      kind: "errorReport",
+      errorReport: e.toString()
+    })
+  );
 }
 
-try {
+async function main(): Promise<void> {
-  startWasiTask().catch(handleError);
+  try {
-} catch (e) {
+    await startWasiTask();
-  handleError(e);
+  } catch (e) {
+    handleError(e);
+  }
 }
+
+main();

package-lock.json

@@ -11,6 +11,7 @@
       "devDependencies": {
         "@bjorn3/browser_wasi_shim": "^0.3.0",
         "@types/node": "^20.12.7",
+        "@types/reconnectingwebsocket": "^1.0.10",
         "esbuild": "^0.14.38",
         "npm-run-all": "^4.1.5",
         "reconnecting-websocket": "^4.4.0",
@@ -32,6 +33,12 @@
         "undici-types": "~5.26.4"
       }
     },
+    "node_modules/@types/reconnectingwebsocket": {
+      "version": "1.0.10",
+      "resolved": "https://registry.npmjs.org/@types/reconnectingwebsocket/-/reconnectingwebsocket-1.0.10.tgz",
+      "integrity": "sha512-30Pq4D3o8BKcdY53dzr0elGFyB/ChYpGrHiRH/GuaZKXXGWq/CsD1QBEu1b8IgdHReOKpo9tjk80UaxSbuXoTQ==",
+      "dev": true
+    },
     "node_modules/ansi-styles": {
       "version": "3.2.1",
       "resolved": "https://registry.npmjs.org/ansi-styles/-/ansi-styles-3.2.1.tgz",
@@ -1318,6 +1325,12 @@
         "undici-types": "~5.26.4"
       }
     },
+    "@types/reconnectingwebsocket": {
+      "version": "1.0.10",
+      "resolved": "https://registry.npmjs.org/@types/reconnectingwebsocket/-/reconnectingwebsocket-1.0.10.tgz",
+      "integrity": "sha512-30Pq4D3o8BKcdY53dzr0elGFyB/ChYpGrHiRH/GuaZKXXGWq/CsD1QBEu1b8IgdHReOKpo9tjk80UaxSbuXoTQ==",
+      "dev": true
+    },
     "ansi-styles": {
       "version": "3.2.1",
       "resolved": "https://registry.npmjs.org/ansi-styles/-/ansi-styles-3.2.1.tgz",

package.json

@@ -23,9 +23,10 @@
   "devDependencies": {
     "@bjorn3/browser_wasi_shim": "^0.3.0",
     "@types/node": "^20.12.7",
+    "@types/reconnectingwebsocket": "^1.0.10",
     "esbuild": "^0.14.38",
     "npm-run-all": "^4.1.5",
     "reconnecting-websocket": "^4.4.0",
     "typescript": "^5.4.5"
   }
-}
+}