refactor: replace commander with parseArgs

package.json

@@ -28,7 +28,6 @@
     "test": "mocha"
   },
   "dependencies": {
-    "commander": "^9.4.0"
   },
   "devDependencies": {
     "chai": "^4.3.6",

src/argsParser.js

@@ -0,0 +1,73 @@
+"use strict";
+const { parseArgs } = require("util");
+
+const mainOptions = {
+  help: { type: 'string', short: "h" },
+  "macho-segment-name": { type: "string" },
+  "output-api-header": { type: "boolean" },
+  overwrite: { type: "boolean" },
+};
+
+function helper(command) {
+  const helpOptionsDescriptions = {
+    help: "display help for command",
+    "macho-segment-name": "--macho-segment-name <segment_name>  Name for the Mach-O segment (default: \"__POSTJECT\")",
+    "output-api-header": "--output-api-header                  Output the API header to stdout",
+    "overwrite": "--overwrite                          Overwrite the resource if it already exists"
+  };
+  if (command) {
+    console.log(helpOptionsDescriptions[command]);
+  }
+  else {
+    console.log("Usage: postject [options] <filename> <resource_name> <resource>");
+    console.log("Inject arbitrary read-only resources into an executable for use at runtime");
+    console.log("");
+    console.log("Arguments:");
+    console.log("  filename        The executable to inject the resource into");
+    console.log("  resource_name   The resource name to use (section name on Mach-O and ELF, resource name for PE)");
+    console.log("  resource        The resource file to inject");
+    console.log("Options:");
+    for (const [key, value] of Object.entries(helpOptionsDescriptions)) {
+      console.log(`  ${value}`);
+    }
+  }
+}
+
+function argumentsParser(clb) {
+
+  const args = process.argv.slice(2);
+  if (args.includes('--help') || args.includes('-h')) {
+    const { values } = parseArgs({ args, options: mainOptions, strict: false, tokens: true });
+    if (typeof values.help === 'string') {
+      helper(values.help);
+    }
+    else {
+      helper();
+    }
+    process.exit();
+  }
+  if (args.length < 3) {
+    console.log("Missing adequate arguments");
+    helper();
+    process.exit(1);
+  }
+  const positionalArgs = args.slice(args.length - 3);
+  const subCommandArgs = args.slice(0, args.length - 3);
+
+  const optionValuesObj = parseArgs({
+    args: subCommandArgs,
+    options: mainOptions,
+    strict: false,
+    tokens: true,
+  }).values;
+  const options = Object.keys(optionValuesObj).reduce((acc, key) => {
+    const camelCaseKey = key.replace(/-([a-z])/g, (g) =>
+      g[1].toUpperCase()
+    );
+    acc[camelCaseKey] = optionValuesObj[key];
+    return acc;
+  }, {});
+  clb(...positionalArgs, options);
+}
+
+module.exports = { argumentsParser };

src/cli.js

@@ -1,9 +1,9 @@
 #!/usr/bin/env node
 
-const program = require("commander");
 const { constants, promises: fs } = require("fs");
 const path = require("path");
 const { inject } = require("./api.js");
+const { argumentParser } = require("./argsParser.js");
 
 async function main(filename, resourceName, resource, options) {
   if (options.outputApiHeader) {
@@ -36,24 +36,5 @@ async function main(filename, resourceName, resource, options) {
 }
 
 if (require.main === module) {
-  program
-    .name("postject")
-    .description(
-      "Inject arbitrary read-only resources into an executable for use at runtime"
-    )
-    .argument("<filename>", "The executable to inject into")
-    .argument(
-      "<resource_name>",
-      "The resource name to use (section name on Mach-O and ELF, resource name for PE)"
-    )
-    .argument("<resource>", "The resource to inject")
-    .option(
-      "--macho-segment-name <segment_name>",
-      "Name for the Mach-O segment",
-      "__POSTJECT"
-    )
-    .option("--output-api-header", "Output the API header to stdout")
-    .option("--overwrite", "Overwrite the resource if it already exists")
-    .action(main)
-    .parse(process.argv);
+  argumentParser(main);
 }