test_runner: preserve user flags in argv

lib/internal/main/test_runner.js

@@ -1,7 +1,8 @@
 'use strict';
 
 const {
-  ArrayPrototypeSlice,
+  ArrayPrototypePush,
+  StringPrototypeStartsWith,
 } = primordials;
 
 const {
@@ -30,7 +31,26 @@ if (isUsingInspector() && options.isolation === 'process') {
   options.inspectPort = process.debugPort;
 }
 
-options.globPatterns = ArrayPrototypeSlice(process.argv, 1);
+const userArgs = [];
+const globPatterns = [];
+let isArg = false;
+
+for (let i = 1; i < process.argv.length; i++) {
+  const arg = process.argv[i];
+  if (isArg) {
+    ArrayPrototypePush(userArgs, arg);
+  } else if (arg === '--') {
+    isArg = true;
+    ArrayPrototypePush(userArgs, arg);
+  } else if (StringPrototypeStartsWith(arg, '-')) {
+    ArrayPrototypePush(userArgs, arg);
+  } else {
+    ArrayPrototypePush(globPatterns, arg);
+  }
+}
+
+options.globPatterns = globPatterns;
+options.argv = userArgs;
 
 debug('test runner configuration:', options);
 run(options).on('test:summary', (data) => {

test/fixtures/test-runner/argv.js

@@ -0,0 +1 @@
+console.log(JSON.stringify(process.argv));

test/parallel/test-runner-cli-args.js

@@ -0,0 +1,47 @@
+'use strict';
+require('../common');
+const assert = require('assert');
+const { spawnSync } = require('child_process');
+const fixtures = require('../common/fixtures');
+
+const testFixture = fixtures.path('test-runner/argv.js');
+
+{
+  const args = ['--test', testFixture, '--hello'];
+  const child = spawnSync(process.execPath, args);
+
+  assert.strictEqual(child.stderr.toString(), '');
+  const stdout = child.stdout.toString();
+  assert.match(stdout, /"--hello"\]/);
+  assert.strictEqual(child.status, 0);
+}
+
+{
+  const args = ['--test', testFixture, '--', '--hello', '--world'];
+  const child = spawnSync(process.execPath, args);
+
+  assert.strictEqual(child.stderr.toString(), '');
+  const stdout = child.stdout.toString();
+  assert.match(stdout, /"--","--hello","--world"\]/);
+  assert.strictEqual(child.status, 0);
+}
+
+{
+  const args = ['--test', testFixture, '--', 'foo.js'];
+  const child = spawnSync(process.execPath, args);
+
+  assert.strictEqual(child.stderr.toString(), '');
+  const stdout = child.stdout.toString();
+  assert.match(stdout, /"--","foo\.js"\]/);
+  assert.strictEqual(child.status, 0);
+}
+
+{
+  const args = ['--test', testFixture, '--hello', '--', 'world'];
+  const child = spawnSync(process.execPath, args);
+
+  assert.strictEqual(child.stderr.toString(), '');
+  const stdout = child.stdout.toString();
+  assert.match(stdout, /"--hello","--","world"\]/);
+  assert.strictEqual(child.status, 0);
+}