Introduce regenerate-expected-files for run-test

Example can be inspector tests.

Bug: v8:10264
Change-Id: I996bb68d0f36920568a04f93cd8c1256a4f41a96
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2070912
Commit-Queue: Z Nguyen-Huu <duongn@microsoft.com>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#66572}

test/inspector/testcfg.py

@@ -62,7 +62,8 @@ class TestCase(testcase.TestCase):
   def output_proc(self):
     return outproc.ExpectedOutProc(
         self.expected_outcomes,
-        os.path.join(self.suite.root, self.path) + EXPECTED_SUFFIX)
+        os.path.join(self.suite.root, self.path) + EXPECTED_SUFFIX,
+        self.suite.test_config.regenerate_expected_files)
 
 
 def GetSuite(*args, **kwargs):

tools/testrunner/base_runner.py

@@ -379,6 +379,8 @@ class BaseTestRunner(object):
                       help="Timeout for single test in seconds")
     parser.add_option("-v", "--verbose", default=False, action="store_true",
                       help="Verbose output")
+    parser.add_option('--regenerate-expected-files', default=False, action='store_true',
+                      help='Regenerate expected files')
 
     # TODO(machenbach): Temporary options for rolling out new test runner
     # features.
@@ -721,6 +723,7 @@ class BaseTestRunner(object):
         shell_dir=self.outdir,
         timeout=timeout,
         verbose=options.verbose,
+        regenerate_expected_files=options.regenerate_expected_files,
     )
 
   def _timeout_scalefactor(self, options):

tools/testrunner/outproc/base.py

@@ -19,8 +19,13 @@ OUTCOMES_FAIL_OR_TIMEOUT = [statusfile.FAIL, statusfile.TIMEOUT]
 class BaseOutProc(object):
   def process(self, output, reduction=None):
     has_unexpected_output = self.has_unexpected_output(output)
+    if has_unexpected_output:
+      self.regenerate_expected_files(output)
     return self._create_result(has_unexpected_output, output, reduction)
 
+  def regenerate_expected_files(self, output):
+    return
+
   def has_unexpected_output(self, output):
     return self.get_outcome(output) not in self.expected_outcomes
 
@@ -125,9 +130,11 @@ class ExpectedOutProc(OutProc):
   """Output processor that has is_failure_output depending on comparing the
   output with the expected output.
   """
-  def __init__(self, expected_outcomes, expected_filename):
+  def __init__(self, expected_outcomes, expected_filename,
+                regenerate_expected_files=False):
     super(ExpectedOutProc, self).__init__(expected_outcomes)
     self._expected_filename = expected_filename
+    self._regenerate_expected_files = regenerate_expected_files
 
   def _is_failure_output(self, output):
     with open(self._expected_filename, 'r') as f:
@@ -143,6 +150,14 @@ class ExpectedOutProc(OutProc):
           return True
       return False
 
+  def regenerate_expected_files(self, output):
+    if not self._regenerate_expected_files:
+      return
+    lines = output.stdout.splitlines()
+    with open(self._expected_filename, 'w') as f:
+      for _, line in enumerate(lines):
+        f.write(line+'\n')
+
   def _act_block_iterator(self, output):
     """Iterates over blocks of actual output lines."""
     lines = output.stdout.splitlines()

tools/testrunner/test_config.py

@@ -19,7 +19,8 @@ class TestConfig(object):
                run_skipped,
                shell_dir,
                timeout,
-               verbose):
+               verbose,
+               regenerate_expected_files=False):
     self.command_prefix = command_prefix
     self.extra_flags = extra_flags
     self.isolates = isolates
@@ -32,3 +33,4 @@ class TestConfig(object):
     self.shell_dir = shell_dir
     self.timeout = timeout
     self.verbose = verbose
+    self.regenerate_expected_files = regenerate_expected_files