[Feat][CLI]: add w4 opt | wasm-opt integration

cli/cli.js

@@ -140,6 +140,16 @@ program.command("bundle <cart>")
         bundle.run(cart, opts);
     });
 
+program.command('opt <cart>')
+    .alias('optimize')
+    .description("optimize and minimize cart size using binaryen wasm-opt")
+    .option("-o, --output <file>", "output wasm file", "./cart-opt.wasm")
+    .option("-s, --silent", "do not print to stdout", false)
+    .action((cart, opts) => {
+        const opt = require("./lib/opt");
+        opt.optimizeCart(cart, opts);
+    });
+
 program
     .name("w4")
     .description("WASM-4: Build retro games using WebAssembly for a fantasy console.\n\nLearn more: https://wasm4.org")

cli/lib/opt.js

@@ -0,0 +1,127 @@
+'use strict';
+const { spawnSync } = require('child_process');
+const path = require('path');
+const fs = require('fs');
+const binaryenPkg = require.resolve('binaryen/package.json');
+const wasmOptBinPath = path.join(path.dirname(binaryenPkg), 'bin/wasm-opt');
+
+const { EOL } = require('os');
+
+const logError = (...args) => {
+  console.error(`w4 opt error: ${args.join(EOL)}`);
+};
+
+const wasmOptFlags = [
+  '-Oz',
+  '--strip-dwarf',
+  '--strip-producers',
+  '--zero-filled-memory',
+];
+
+/**
+ * @type {(bytes: number) => string}
+ */
+const formatKiB = (bytes) => {
+  return (bytes / 1024).toFixed(3) + 'KiB';
+};
+
+/**
+ * @type {(num: number, den: number) => string}
+ */
+const formatPercent = (num, den) => {
+  return `${((num / den) * 100).toFixed(2)}%`;
+};
+
+/**
+ * @type{(cart: string, options: { output: string, silent: boolean }) => void}
+ */
+function optimizeCart(cart, { output, silent }) {
+  const absoluteInputCartPath = path.isAbsolute(cart)
+    ? cart
+    : path.resolve(process.cwd(), cart);
+
+  const absoluteOutputCartPath = path.isAbsolute(output)
+    ? output
+    : path.resolve(process.cwd(), output);
+
+  /**
+   * @type {import('fs').Stats | null}
+   */
+  let inCartStats = null;
+  /**
+   * @type {import('fs').Stats | null}
+   */
+  let outCartStats = null;
+
+  try {
+    inCartStats = fs.statSync(absoluteInputCartPath);
+
+    if (inCartStats.isDirectory()) {
+      logError(`cart "${absoluteInputCartPath}" is a directory.`);
+      process.exitCode = 1;
+      return;
+    }
+  } catch (err) {
+    if (err?.code === 'ENOENT') {
+      logError(`cart "${absoluteInputCartPath}" not found.`);
+    } else {
+      logError(err);
+    }
+
+    process.exitCode = 1;
+    return;
+  }
+
+  // @see https://nodejs.org/api/child_process.html#child_processspawnsynccommand-args-options
+  const wasmOptProcess = spawnSync(wasmOptBinPath, [
+    absoluteInputCartPath,
+    '-o',
+    absoluteOutputCartPath,
+    ...wasmOptFlags,
+  ]);
+
+  // status is the `exitCode`
+  if (wasmOptProcess.status) {
+    process.exitCode = wasmOptProcess.status;
+
+    logError(
+      `an error has occurred while running wasm-opt. Exit code ${wasmOptProcess.status}`
+    );
+
+    process.stderr.write(wasmOptProcess.stderr);
+    return;
+  }
+
+  // wasmOptProcess.error Error | null: `The error object if the child process failed or timed out.`
+  if (wasmOptProcess.error) {
+    process.exitCode = 1;
+    logError(
+      `an error has occurred while running wasm-opt. Error ${wasmOptProcess.error}`
+    );
+    process.stderr.write(wasmOptProcess.stderr);
+
+    return;
+  }
+
+  if (!silent) {
+    outCartStats = fs.statSync(absoluteOutputCartPath);
+
+    process.stdout.write(
+      [
+        'w4 opt',
+        `- input:  ${formatKiB(inCartStats.size)} ${absoluteInputCartPath}`,
+        `- output: ${formatKiB(outCartStats.size)} ${absoluteOutputCartPath}`,
+        `size reduction: ${formatPercent(
+          inCartStats.size - outCartStats.size,
+          inCartStats.size
+        )}`,
+      ]
+        .join(EOL)
+        .concat(EOL)
+    );
+  }
+}
+
+module.exports = {
+  optimizeCart,
+};

cli/package.json

@@ -34,6 +34,7 @@
     "zig"
   ],
   "dependencies": {
+    "binaryen": "104.0.0",
     "commander": "^8.2.0",
     "express": "^4.17.1",
     "mustache": "^4.2.0",

site/docs/reference/cli.md

@@ -311,6 +311,46 @@ The `--title` option changes the visible title of the game. Like in the title ba
 At least one of the targets (`--html`, `--windows`, `--linux`, `--mac`) must be provided. If no target is provided, the command will fail.
 :::
 
+## `opt`
+
+**Summary:**
+
+Shrinks input wasm file and optimizes it.
+
+Powered by [binaryen](https://github.com/AssemblyScript/binaryen.js).
+
+**Usage:**
+
+```
+w4 opt <CART> [OPTIONS]
+w4 optimize <CART> [OPTIONS]
+```
+
+**Description:**
+
+`w4 opt` generates an optimized version of the input wasm module using [`wasm-opt`](https://github.com/WebAssembly/binaryen#binaryen-optimizations).
+
+**Examples:**
+
+```
+
+w4 opt carts/wormhole.wasm
+w4 opt target/wasm32-unknown-unknown/release/snake.wasm snake.opt.wasm 
+w4 opt carts/minesweeper.wasm -s
+```
+
+**Options:**
+
+| Option           | Default value | Description                             |
+| ---------------- | ------------- | --------------------------------------- |
+| -s               |               | Do not print to stdout                  |
+| -silent          |               | Same as `-s`                            |
+| -o FILE          | cart-opt.wasm | Output file                             |
+| --output FILE    | cart-opt.wasm | Same as `-o`                            |
+
+**Alias:** `optimize`
+
+
 ## `help`
 
 **Summary:**