test_runner: avoid validating options.bail if not provided

Author: pmarchini

lib/internal/test_runner/runner.js

@@ -588,7 +588,7 @@ function run(options = kEmptyObject) {
     execArgv = [],
     argv = [],
     cwd = process.cwd(),
-    bail = false,
+    bail,
   } = options;
 
   if (files != null) {
@@ -688,14 +688,16 @@ function run(options = kEmptyObject) {
 
   validateStringArray(argv, 'options.argv');
   validateStringArray(execArgv, 'options.execArgv');
-  validateBoolean(bail, 'options.bail');
-  // TODO(pmarchini): watch mode with bail needs to be implemented
-  if (bail && watch) {
-    throw new ERR_INVALID_ARG_VALUE(
-      'options.bail',
-      watch,
-      'bail is not supported while watch mode is enabled',
-    );
+  if (bail != null) {
+    validateBoolean(bail, 'options.bail');
+    // TODO(pmarchini): watch mode with bail needs to be implemented
+    if (bail && watch) {
+      throw new ERR_INVALID_ARG_VALUE(
+        'options.bail',
+        watch,
+        'bail is not supported while watch mode is enabled',
+      );
+    }
   }
 
   const rootTestOptions = { __proto__: null, concurrency, timeout, signal };