Improve error message when server crashes

Give the exact command that the user needs to type to open the server logfile
when the server unexpectedly crashes.

python/ycm/tests/youcompleteme_test.py

@@ -28,7 +28,7 @@ MockVimModule()
 
 import os
 import sys
-from hamcrest import ( assert_that, contains, empty, is_in, is_not, has_length,
+from hamcrest import ( assert_that, contains, empty, equal_to, is_in, is_not,
                        matches_regexp )
 from mock import call, MagicMock, patch
 
@@ -53,23 +53,19 @@ def RunNotifyUserIfServerCrashed( ycm, test, post_vim_message ):
 
   ycm._NotifyUserIfServerCrashed()
 
-  assert_that( ycm._logger.method_calls,
+  assert_that( ycm._logger.error.call_args[ 0 ][ 0 ],
-               has_length( len( test[ 'expected_logs' ] ) ) )
+               test[ 'expected_message' ] )
-  ycm._logger.error.assert_has_calls(
+  assert_that( post_vim_message.call_args[ 0 ][ 0 ],
-    [ call( log ) for log in test[ 'expected_logs' ] ] )
+               test[ 'expected_message' ] )
-  post_vim_message.assert_has_exact_calls( [
-    call( test[ 'expected_vim_message' ] )
-  ] )
 
 
 def YouCompleteMe_NotifyUserIfServerCrashed_UnexpectedCore_test():
-  message = ( "The ycmd server SHUT DOWN (restart with ':YcmRestartServer'). "
+  message = ( "The ycmd server SHUT DOWN \(restart with ':YcmRestartServer'\). "
-              "Unexpected error while loading the YCM core library. "
+              "Unexpected error while loading the YCM core library. Type "
-              "Use the ':YcmToggleLogs' command to check the logs." )
+              "':YcmToggleLogs ycmd_\d+_stderr_.+.log' to check the logs." )
   RunNotifyUserIfServerCrashed( {
     'return_code': 3,
-    'expected_logs': [ message ],
+    'expected_message': matches_regexp( message )
-    'expected_vim_message': message
   } )
 
 
@@ -79,8 +75,7 @@ def YouCompleteMe_NotifyUserIfServerCrashed_MissingCore_test():
               "using it. Follow the instructions in the documentation." )
   RunNotifyUserIfServerCrashed( {
     'return_code': 4,
-    'expected_logs': [ message ],
+    'expected_message': equal_to( message )
-    'expected_vim_message': message
   } )
 
 
@@ -91,8 +86,7 @@ def YouCompleteMe_NotifyUserIfServerCrashed_Python2Core_test():
               "interpreter path." )
   RunNotifyUserIfServerCrashed( {
     'return_code': 5,
-    'expected_logs': [ message ],
+    'expected_message': equal_to( message )
-    'expected_vim_message': message
   } )
 
 
@@ -103,8 +97,7 @@ def YouCompleteMe_NotifyUserIfServerCrashed_Python3Core_test():
               "interpreter path." )
   RunNotifyUserIfServerCrashed( {
     'return_code': 6,
-    'expected_logs': [ message ],
+    'expected_message': equal_to( message )
-    'expected_vim_message': message
   } )
 
 
@@ -114,19 +107,17 @@ def YouCompleteMe_NotifyUserIfServerCrashed_OutdatedCore_test():
               "install.py script. See the documentation for more details." )
   RunNotifyUserIfServerCrashed( {
     'return_code': 7,
-    'expected_logs': [ message ],
+    'expected_message': equal_to( message )
-    'expected_vim_message': message
   } )
 
 
 def YouCompleteMe_NotifyUserIfServerCrashed_UnexpectedExitCode_test():
-  message = ( "The ycmd server SHUT DOWN (restart with ':YcmRestartServer'). "
+  message = ( "The ycmd server SHUT DOWN \(restart with ':YcmRestartServer'\). "
-              "Unexpected exit code 1. Use the ':YcmToggleLogs' command to "
+              "Unexpected exit code 1. Type "
-              "check the logs." )
+              "':YcmToggleLogs ycmd_\d+_stderr_.+.log' to check the logs." )
   RunNotifyUserIfServerCrashed( {
     'return_code': 1,
-    'expected_logs': [ message ],
+    'expected_message': matches_regexp( message )
-    'expected_vim_message': message
   } )
 
 

python/ycm/youcompleteme.py

@@ -79,10 +79,10 @@ SERVER_SHUTDOWN_MESSAGE = (
   "The ycmd server SHUT DOWN (restart with ':YcmRestartServer')." )
 EXIT_CODE_UNEXPECTED_MESSAGE = (
   "Unexpected exit code {code}. "
-  "Use the ':YcmToggleLogs' command to check the logs." )
+  "Type ':YcmToggleLogs {logfile}' to check the logs." )
 CORE_UNEXPECTED_MESSAGE = (
   "Unexpected error while loading the YCM core library. "
-  "Use the ':YcmToggleLogs' command to check the logs." )
+  "Type ':YcmToggleLogs {logfile}' to check the logs." )
 CORE_MISSING_MESSAGE = (
   'YCM core library not detected; you need to compile YCM before using it. '
   'Follow the instructions in the documentation.' )
@@ -238,8 +238,10 @@ class YouCompleteMe( object ):
     self._user_notified_about_crash = True
 
     return_code = self._server_popen.poll()
+    logfile = os.path.basename( self._server_stderr )
     if return_code == server_utils.CORE_UNEXPECTED_STATUS:
-      error_message = CORE_UNEXPECTED_MESSAGE
+      error_message = CORE_UNEXPECTED_MESSAGE.format(
+          logfile = logfile )
     elif return_code == server_utils.CORE_MISSING_STATUS:
       error_message = CORE_MISSING_MESSAGE
     elif return_code == server_utils.CORE_PYTHON2_STATUS:
@@ -249,7 +251,9 @@ class YouCompleteMe( object ):
     elif return_code == server_utils.CORE_OUTDATED_STATUS:
       error_message = CORE_OUTDATED_MESSAGE
     else:
-      error_message = EXIT_CODE_UNEXPECTED_MESSAGE.format( code = return_code )
+      error_message = EXIT_CODE_UNEXPECTED_MESSAGE.format(
+          code = return_code,
+          logfile = logfile )
 
     error_message = SERVER_SHUTDOWN_MESSAGE + ' ' + error_message
     self._logger.error( error_message )