no child-process - no second options parsing

bin/mocha

@@ -17,9 +17,7 @@ const {
   isNodeFlag,
   impliesNoTimeouts
 } = require('../lib/cli/node-flags');
-const unparse = require('yargs-unparser');
 const debug = require('debug')('mocha:cli:mocha');
-const {aliases} = require('../lib/cli/run-option-metadata');
 const nodeEnv = require('node-environment-flags');
 
 const mochaArgs = {};
@@ -120,6 +118,8 @@ if (nodeArgs.gc) {
 if (Object.keys(nodeArgs).length) {
   const {spawn} = require('child_process');
   const mochaPath = require.resolve('../lib/cli/cli.js');
+  const unparse = require('yargs-unparser');
+  const {aliases} = require('../lib/cli/run-option-metadata');
 
   debug('final node args', nodeArgs);
 
@@ -151,5 +151,5 @@ if (Object.keys(nodeArgs).length) {
     proc.kill('SIGTERM'); // if that didn't work, we're probably in an infinite loop, so make it die.
   });
 } else {
-  require('../lib/cli/cli').main(unparse(mochaArgs, {alias: aliases}));
+  require('../lib/cli/cli').main(['preParsedOptions', mochaArgs]);
 }

lib/cli/cli.js

@@ -34,7 +34,7 @@ exports.main = (argv = process.argv.slice(2)) => {
 
   Error.stackTraceLimit = Infinity; // configurable via --stack-trace-limit?
 
-  var args = loadOptions(argv);
+  var args = argv[0] === 'preParsedOptions' ? argv[1] : loadOptions(argv);
 
   yargs()
     .scriptName('mocha')