added unit testing, and started implementing unit tests...phew

node_modules/mocha/lib/cli/cli.js

@@ -0,0 +1,68 @@
+'use strict';
+
+/**
+ * This is where we finally parse and handle arguments passed to the `mocha` executable.
+ * Option parsing is handled by {@link https://npm.im/yargs yargs}.
+ * If executed via `node`, this module will run {@linkcode module:lib/cli/cli.main main()}.
+ *
+ * @private
+ * @module
+ */
+
+const debug = require('debug')('mocha:cli:cli');
+const symbols = require('log-symbols');
+const yargs = require('yargs');
+const path = require('path');
+const {loadOptions} = require('./options');
+const commands = require('./commands');
+const ansi = require('ansi-colors');
+const {repository, homepage, version, gitter} = require('../../package.json');
+
+/**
+ * - Accepts an `Array` of arguments
+ * - Modifies {@link https://nodejs.org/api/modules.html#modules_module_paths Node.js' search path} for easy loading of consumer modules
+ * - Sets {@linkcode https://nodejs.org/api/errors.html#errors_error_stacktracelimit Error.stackTraceLimit} to `Infinity`
+ * @summary Mocha's main entry point from the command-line.
+ * @param {string[]} argv - Array of arguments to parse, or by default the lovely `process.argv.slice(2)`
+ */
+exports.main = (argv = process.argv.slice(2)) => {
+  debug('entered main with raw args', argv);
+  // ensure we can require() from current working directory
+  module.paths.push(process.cwd(), path.resolve('node_modules'));
+
+  Error.stackTraceLimit = Infinity; // configurable via --stack-trace-limit?
+
+  yargs
+    .scriptName('mocha')
+    .command(commands.run)
+    .command(commands.init)
+    .updateStrings({
+      'Positionals:': 'Positional Arguments',
+      'Options:': 'Other Options',
+      'Commands:': 'Commands'
+    })
+    .fail((msg, err, yargs) => {
+      debug(err);
+      yargs.showHelp();
+      console.error(`\n${symbols.error} ${ansi.red('ERROR:')} ${msg}`);
+      process.exit(1);
+    })
+    .help('help', 'Show usage information & exit')
+    .alias('help', 'h')
+    .version('version', 'Show version number & exit', version)
+    .alias('version', 'V')
+    .wrap(process.stdout.columns ? Math.min(process.stdout.columns, 80) : 80)
+    .epilog(
+      `Mocha Resources
+    Chat: ${ansi.magenta(gitter)}
+  GitHub: ${ansi.blue(repository.url)}
+    Docs: ${ansi.yellow(homepage)}
+      `
+    )
+    .parse(argv, loadOptions(argv));
+};
+
+// allow direct execution
+if (require.main === module) {
+  exports.main();
+}