Build declarations as well

Author: kddnewton

bin/build

@@ -1,5 +1,6 @@
 #!/usr/bin/env node
 
+const { execSync } = require("child_process");
 const esbuild = require("esbuild");
 const path = require("path");
 
@@ -9,48 +10,18 @@ const wasmPlugin = {
     let path = require("path")
     let fs = require("fs")
 
-    // Resolve ".wasm" files to a path with a namespace
-    build.onResolve({ filter: /\.wasm$/ }, (args) => {
-      // If this is the import inside the stub module, import the
-      // binary itself. Put the path in the "wasm-binary" namespace
-      // to tell our binary load callback to load the binary file.
-      if (args.namespace === "wasm-stub") {
-        return { path: args.path, namespace: "wasm-binary" };
-      }
+    build.onLoad({ filter: /\.wasm$/ }, async (args) => ({
+      contents: await fs.promises.readFile(args.path),
+      loader: "binary"
+    }));
 
-      // Otherwise, generate the JavaScript stub module for this
-      // ".wasm" file. Put it in the "wasm-stub" namespace to tell
-      // our stub load callback to fill it with JavaScript.
-      //
-      // Resolve relative paths to absolute paths here since this
-      // resolve callback is given "resolveDir", the directory to
-      // resolve imports against.
-      if (args.resolveDir === "") {
-        return; // Ignore unresolvable paths
+    // When we're done building the output, we'll want to additionally build the
+    // typescript declarations file.
+    build.onEnd((result) => {
+      if (result.errors.length === 0) {
+        execSync("./node_modules/.bin/tsc");
       }
-
-      return {
-        path: path.isAbsolute(args.path) ? args.path : path.join(args.resolveDir, args.path),
-        namespace: "wasm-stub"
-      };
     });
-
-    // Virtual modules in the "wasm-stub" namespace are filled with
-    // the JavaScript code for compiling the WebAssembly binary. The
-    // binary itself is imported from a second virtual module.
-    build.onLoad({ filter: /.*/, namespace: "wasm-stub" }, async (args) => ({
-      contents: `import wasm from ${JSON.stringify(args.path)};
-        export default (imports) => WebAssembly.instantiate(wasm, imports).then((result) => result.instance);`,
-    }));
-
-    // Virtual modules in the "wasm-binary" namespace contain the
-    // actual bytes of the WebAssembly file. This uses esbuild's
-    // built-in "binary" loader instead of manually embedding the
-    // binary data inside JavaScript code ourselves.
-    build.onLoad({ filter: /.*/, namespace: "wasm-binary" }, async (args) => ({
-      contents: await fs.promises.readFile(args.path),
-      loader: "binary",
-    }));
   }
 };
 

package.json

@@ -18,11 +18,13 @@
     "@wasmer/wasi": "^0.12.0",
     "@wasmer/wasmfs": "^0.12.0",
     "path-browserify": "^1.0.1",
+    "randomfill": "^1.0.4",
     "ruby-head-wasm-wasi": "^0.3.0"
   },
   "devDependencies": {
     "@types/node": "^17.0.33",
     "@types/path-browserify": "^1.0.0",
-    "esbuild": "^0.14.39"
+    "esbuild": "^0.14.39",
+    "typescript": "^4.7.4"
   }
 }

src/app.d.ts

@@ -0,0 +1,8 @@
+declare module "*.wasm" {
+  const buffer: BufferSource;
+  export default buffer;
+}
+
+declare module "randomfill" {
+  export function randomFillSync<T>(buffer: T, offset: number, size: number): T;
+}

src/declarations.d.ts

@@ -1,10 +1,16 @@
-import crypto from "crypto";
 import { WASI } from "@wasmer/wasi";
 import { WasmFs } from "@wasmer/wasmfs";
-import path from "path-browserify";
 import { RubyVM } from "ruby-head-wasm-wasi/dist/index";
 
-import load from "./app.wasm";
+import { randomFillSync } from "randomfill";
+import path from "path-browserify";
+
+import app from "./app.wasm";
+
+type AppExports = {
+  _initialize: () => void;
+  memory: WebAssembly.Memory;
+};
 
 // This overwrites the default writeSync function used by the WasmFs to instead
 // pipe it out to the console.
@@ -31,7 +37,18 @@ function createWriter(originalWriter: Function) {
   }
 }
 
-export default async function createRuby() {
+type SyntaxTreeHandler = {
+  format(source: string): string;
+  parse(source: string): string;
+  read(filepath: string): string;
+};
+
+export type SyntaxTree = {
+  rubyVM: RubyVM;
+  handlers: Record<"haml" | "ruby", SyntaxTreeHandler>;
+};
+
+export default async function createSyntaxTree(): Promise<SyntaxTree> {
   // First, create a new file system that we can use internally within the Ruby
   // WASM VM.
   const wasmFs = new WasmFs();
@@ -41,12 +58,7 @@ export default async function createRuby() {
   // Next, create a new WASI instance with the correct options overridden from
   // the defaults.
   const wasi = new WASI({
-    bindings: {
-      ...WASI.defaultBindings,
-      fs: wasmFs.fs,
-      path: path,
-      randomFillSync: crypto.randomFillSync as typeof WASI.defaultBindings.randomFillSync,
-    },
+    bindings: { ...WASI.defaultBindings, fs: wasmFs.fs, path, randomFillSync },
     preopens: { "/": "/tmp" }
   });
 
@@ -57,7 +69,11 @@ export default async function createRuby() {
   rubyVM.addToImports(imports);
 
   // Set the WASI memory to use the memory for our application.
-  const instance = await load(imports);
+  const instance = await WebAssembly.instantiate(app, imports).then((result) => {
+    return result.instance as WebAssembly.Instance & { exports: AppExports };
+  });
+
+  // Make sure WASI and our web assembly instance share their memory.
   wasi.setMemory(instance.exports.memory);
 
   // Load our application into the virtual machine.
@@ -83,22 +99,43 @@ export default async function createRuby() {
 
   return {
     rubyVM,
-    formatHAML(source: string) {
-      return format(source, ".haml");
-    },
-    formatRuby(source: string) {
-      return format(source, ".rb");
-    },
-    // formatRBS(source: string) {
-    //   return format(source, ".rbs");
-    // }
+    handlers: {
+      haml: makeSyntaxTreeHandler(".haml"),
+      // rbs: makeSyntaxTreeHandler(".rbs"),
+      ruby: makeSyntaxTreeHandler(".rb")
+    }
   };
 
-  function format(source: string, kind: string) {
-    const jsonSource = JSON.stringify(JSON.stringify(source));
-    const rubySource = `SyntaxTree::HANDLERS.fetch("${kind}").format(JSON.parse(${jsonSource}))`;
-    return rubyVM.eval(rubySource).toString();
+  function makeSyntaxTreeHandler(extension: string): SyntaxTreeHandler {
+    return {
+      format(source) {
+        const jsonSource = JSON.stringify(JSON.stringify(source));
+        const rubySource = `
+          handler = SyntaxTree::HANDLERS["${extension}"]
+          handler.format(JSON.parse(${jsonSource}))
+        `;
+
+        return rubyVM.eval(rubySource).toString();
+      },
+      parse(source) {
+        const jsonSource = JSON.stringify(JSON.stringify(source));
+        const rubySource = `
+          handler = SyntaxTree::HANDLERS["${extension}"]
+          node = handler.parse(JSON.parse(${jsonSource}))
+          PP.pp(node, +"", 80)
+        `;
+
+        return rubyVM.eval(rubySource).toString();
+      },
+      read(filepath) {
+        const jsonSource = JSON.stringify(JSON.stringify(filepath));
+        const rubySource = `
+          handler = SyntaxTree::HANDLERS["${extension}"]
+          handler.read(JSON.parse(${jsonSource}))
+        `;
+
+        return rubyVM.eval(rubySource).toString();
+      }
+    };
   }
 };
-
-export type Ruby = Awaited<ReturnType<typeof createRuby>>;

src/index.ts

@@ -1,9 +1,12 @@
 {
   "compilerOptions": {
+    "declaration": true,
+    "emitDeclarationOnly": true,
     "esModuleInterop": true,
     "module": "commonjs",
     "moduleResolution": "node",
     "noImplicitAny": true,
+    "outDir": "./dist",
     "strict": true
   },
   "include": ["src"]

tsconfig.json

@@ -304,6 +304,11 @@ tar-stream@^2.1.0:
     inherits "^2.0.3"
     readable-stream "^3.1.1"
 
+typescript@^4.7.4:
+  version "4.7.4"
+  resolved "https://registry.yarnpkg.com/typescript/-/typescript-4.7.4.tgz#1a88596d1cf47d59507a1bcdfb5b9dfe4d488235"
+  integrity sha512-C0WQT0gezHuw6AdY1M2jxUO83Rjf0HP7Sk1DtXj6j1EwkQNZrHAg2XPWlq62oqEhYvONq5pkC2Y9oPljWToLmQ==
+
 util-deprecate@^1.0.1:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/util-deprecate/-/util-deprecate-1.0.2.tgz#450d4dc9fa70de732762fbd2d4a28981419a0ccf"