Support JSKit demo and update initial sample

Author: kateinoigakukun

package-lock.json

@@ -19,7 +19,9 @@
     "build:prod": "webpack --mode production",
     "start": "webpack-dev-server"
   },
-  "dependencies": {},
+  "dependencies": {
+    "javascript-kit-swift": "^0.15.0"
+  },
   "devDependencies": {
     "@types/codemirror": "5.60.5",
     "@wasmer/wasi": "^0.12.0",

package.json

@@ -1,5 +1,3 @@
-import Glibc
-
 print("Hello, 🌐!")
 
 // we can try loops and arithmetic:
@@ -37,13 +35,12 @@ func fib(n: Int) -> Int {
 print("The 10th Fibonacci number is \(fib(n: 10))")
 
 // we can also run JavaScript from Swift.
-
-@_silgen_name("executeScript")
-func executeScript(script: UnsafePointer<UInt8>, length: Int32)
-
-// Here's a string holding JavaScript code, with some string interpolation:
-var scriptSrc = "alert('Hello from Swift! The 11th Fibonacci number is \(fib(n: 11))');"
-// and we can execute it.
-scriptSrc.withUTF8 { bufferPtr in
-  executeScript(script: bufferPtr.baseAddress!, length: Int32(bufferPtr.count))
+import JavaScriptKit
+
+let reply = JSObject.global.prompt!("Please input number here")
+let alert = JSObject.global.alert!
+if let n = Int(reply.string!) {
+    alert("The \(n)th Fibonacci number is \(fib(n: n))")
+} else {
+    alert("\(reply) is not a number :(")
 }

public/demo_compiled/program.wasm.txt

@@ -2,6 +2,7 @@ import CodeMirror from "codemirror";
 
 import "codemirror/mode/swift/swift";
 import "codemirror/lib/codemirror.css";
+import { SwiftRuntime } from "javascript-kit-swift";
 import kDefaultDemoScript from './demo.swift?raw';
 
 const kCompileApi = "https://swiftwasm-compiler-api-mgv5x4syda-uc.a.run.app";
@@ -111,6 +112,25 @@ async function compileCode(code: string): Promise<CompilationResult> {
   }
 }
 
+export const wrapWASI = (wasiObject: any) => {
+  // PATCH: @wasmer-js/wasi@0.x forgets to call `refreshMemory` in `clock_res_get`,
+  // which writes its result to memory view. Without the refresh the memory view,
+  // it accesses a detached array buffer if the memory is grown by malloc.
+  // But they wasmer team discarded the 0.x codebase at all and replaced it with
+  // a new implementation written in Rust. The new version 1.x is really unstable
+  // and not production-ready as far as katei investigated in Apr 2022.
+  // So override the broken implementation of `clock_res_get` here instead of
+  // fixing the wasi polyfill.
+  // Reference: https://github.com/wasmerio/wasmer-js/blob/55fa8c17c56348c312a8bd23c69054b1aa633891/packages/wasi/src/index.ts#L557
+  const original_clock_res_get = wasiObject.wasiImport["clock_res_get"];
+
+  wasiObject.wasiImport["clock_res_get"] = function() {
+      wasiObject.refreshMemory();
+      return Reflect.apply(original_clock_res_get, this, arguments);
+  };
+  return wasiObject.wasiImport;
+};
+
 async function runWasm(wasmBuffer: ArrayBuffer) {
   writeOutputArea("Running WebAssembly...\n");
   const { WasmFs } = await import("@wasmer/wasmfs");
@@ -137,28 +157,20 @@ async function runWasm(wasmBuffer: ArrayBuffer) {
       fs: wasmFs.fs,
     },
   });
-
-  let _instance: WebAssembly.Instance;
-  const importObject = {
-    env: {
-      executeScript: (ptr: number, len: number) => {
-        const uint8Memory = new Uint8Array(
-          (_instance.exports.memory as any).buffer
-        );
-        const script = decoder.decode(uint8Memory.subarray(ptr, ptr + len));
-        new Function(script)();
-      },
-    },
-  };
+  const swift = new SwiftRuntime();
 
   const { instance } = await WebAssembly.instantiate(wasmBuffer, {
     wasi_snapshot_preview1: wasi.wasiImport,
     wasi_unstable: wasi.wasiImport,
-    ...importObject,
+    javascript_kit: swift.wasmImports as any,
   });
 
-  _instance = instance;
-  wasi.start(instance);
+  wasi.setMemory(instance.exports.memory as any);
+  (instance.exports._initialize as any)();
+  if (instance.exports.swjs_library_version) {
+    swift.setInstance(instance);
+  }
+  (instance.exports.main as any)();
 }
 
 function populateResultsArea(compileResult: CompilationResult) {

src/demo.swift

@@ -0,0 +1,4 @@
+curl 'https://swiftwasm-compiler-api-mgv5x4syda-uc.a.run.app/' \
+  -o ./public/demo_compiled/program.wasm.txt \
+  -H 'content-type: application/json' \
+  --data-raw "$(jq -n --arg data "$(cat ./src/demo.swift)" '{"mainCode":$data,"action":"emitExecutable"}')"