init

2023-09-18 01:13:38 +00:00
commit 7751908620
45 changed files with 3072 additions and 0 deletions
@@ -0,0 +1,93 @@
+const debugHelper = require('./debug-helper')
+
+/**
+ * Parse command line arguments
+ */
+class Arguments {
+  flags = {}
+
+  options = {}
+
+  arguments = []
+}
+exports.Arguments = Arguments
+
+const helpCode = 'ARGHELP'
+exports.helpCode = helpCode
+
+const errorCode = 'ARGV'
+exports.errorCode = errorCode
+
+/**
+ * Parses the command line arguments
+ * @param {string[]} flags       Allowed flags
+ * @param {string[]} options     Allowed options
+ * @param {boolean} allowArgs    Whether to allow unnamed arguments
+ * @returns {Arguments}
+ */
+function parse(flags, options, allowArgs) {
+  flags = flags || []
+  options = options || []
+  allowArgs = typeof(allowArgs) === 'boolean' ? allowArgs : true
+
+  const result = new Arguments()
+
+  // Check for --help
+  const argv = process.argv.slice(2)
+  if (argv.some(x => x === '--help')) {
+    throwError('Help requested', helpCode)
+  }
+
+  // Parse
+  for (let i = 0; i < argv.length; i++) {
+    const arg = argv[i]
+    const nextArg = i + 1 < argv.length ? argv[i + 1] : null
+
+    // Starts with "--"
+    if (arg.startsWith('--')) {
+      const name = arg.substr(2)
+
+      // Legal flag
+      if (flags.some(x => x === name)) {
+        debugHelper.debug(`arg: ${arg} (flag)`)
+        result.flags[name] = true
+        continue
+      }
+
+      // Unknown option
+      if (!options.some(x => x === name)) {
+        throwError(`Unknown option '${name}'`)
+      }
+
+      // Missing value following option
+      if (nextArg === null || nextArg.startsWith('--')) {
+        throwError(`Option '${name}' must have a value`)
+      }
+
+      // Legal option
+      debugHelper.debug(`arg: ${arg} (option)`)
+      result.options[name] = nextArg
+      i++
+      continue
+    }
+
+    // Unexpected argument
+    if (!allowArgs) {
+      throwError(`Unexpected argument '${arg}'`)
+    }
+
+    // Legal argument
+    debugHelper.debug(`arg: ${arg}`)
+    result.arguments.push(arg)
+  }
+
+  return result
+}
+exports.parse = parse
+
+function throwError(message, code) {
+  const err = new Error(message)
+  err.code = code || errorCode
+  throw err
+}
+exports.throwError = throwError