Display content_shell error messages.

third_party/WebKit/Tools/Scripts/webkitpy/layout_tests/port/driver.py

 # Copyright (C) 2011 Google Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 # copyright notice, this list of conditions and the following disclaimer
@@ skipping 17 matching lines @@
 
 import base64
 import logging
 import re
 import shlex
 import sys
 import time
 
 from webkitpy.common.system import path
 from webkitpy.common.system.profiler import ProfilerFactory
+from webkitpy.layout_tests.port.server_process import quote_data
 
 
 _log = logging.getLogger(__name__)
 
 
 DRIVER_START_TIMEOUT_SECS = 30
 
 
 class DriverInput(object):
 
@@ skipping 282 matching lines @@
                 _log.error("content_shell took too long to startup.")
 
     def _wait_for_server_process_output(self, server_process, deadline, text):
         output = ''
         line = server_process.read_stdout_line(deadline)
         while not server_process.timed_out and not server_process.has_crashed() and not text in line.rstrip():
             output += line
             line = server_process.read_stdout_line(deadline)
 
         if server_process.timed_out or server_process.has_crashed():
+            # Print stdout and stderr if the process failed to start.
+            # Adapted from ServerProcess._log_data().
+            for line in quote_data(output):
+                _log.error('%s: %s', 'OUT', line)
+            for line in quote_data(server_process.pop_all_buffered_stderr()):
+                _log.error('%s: %s', 'ERR', line)
             _log.error('Failed to start the %s process: \n%s', server_process.name(), output)

[Dirk Pranke, 2016/11/29 02:20:48]

Doesn't this result in double-logging things, since we're logging output on line
347 as well?

[Jack Bates, 2016/12/01 17:47:38]

Oops! Yes. How did I miss that? Thank you. I uploaded a new patch.

             return False
 
         return True
 
     def _run_post_start_tasks(self):
         # Remote drivers may override this to delay post-start tasks until the server has ack'd.
         if self._profiler:
             self._profiler.attach_to_pid(self._pid_on_target())
 
     def _pid_on_target(self):
@@ skipping 193 matching lines @@
         self.decoded_content = None
         self.malloc = None
         self.js_heap = None
         self.stdin_path = None
 
     def decode_content(self):
         if self.encoding == 'base64' and self.content is not None:
             self.decoded_content = base64.b64decode(self.content)
         else:
             self.decoded_content = self.content