Auto merge of #3247 - micbou:diagnostic-matches-current-window, r=puremourning

[READY] Update diagnostic matches only in current window

Unfortunately, switching windows when updating the diagnostic matches causes too many side-effects like issues #3228 and #3242. Revert PRs https://github.com/Valloric/YouCompleteMe/pull/3024 and https://github.com/Valloric/YouCompleteMe/pull/3229 and only update matches in the current window.

Fixes #3242.

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python/ycm/diagnostic_interface.py

@@ -129,9 +129,10 @@ class DiagnosticInterface( object ):
     if not self._user_options[ 'enable_diagnostic_highlighting' ]:
       return
 
-    with vimsupport.CurrentWindow():
-      for window in vimsupport.GetWindowsForBufferNumber( self._bufnr ):
-        vimsupport.SwitchWindow( window )
+    # Vim doesn't provide a way to update the matches for a different window
+    # than the current one (which is a view of the current buffer).
+    if vimsupport.GetCurrentBufferNumber() != self._bufnr:
+      return
 
     matches_to_remove = vimsupport.GetDiagnosticMatchesInCurrentWindow()
 

python/ycm/tests/youcompleteme_test.py

@@ -1047,14 +1047,13 @@ def YouCompleteMe_AsyncDiagnosticUpdate_PerFile_test( ycm,
     ] )
   ] )
 
+  # FIXME: diagnostic matches in windows other than the current one are not
+  # updated.
   assert_that(
     test_utils.VIM_MATCHES_FOR_WINDOW,
     has_entries( {
       1: contains(
         VimMatch( 'YcmErrorSection', '\\%1l\\%1c\\_.\\{-}\\%1l\\%1c' )
-      ),
-      3: contains(
-        VimMatch( 'YcmErrorSection', '\\%3l\\%3c\\_.\\{-}\\%3l\\%3c' )
       )
     } )
   )

python/ycm/vimsupport.py

@@ -23,7 +23,6 @@ from __future__ import absolute_import
 from builtins import *  # noqa
 
 from future.utils import iterkeys
-import contextlib
 import vim
 import os
 import json
@@ -1218,49 +1217,6 @@ def BuildRange( start_line, end_line ):
   }
 
 
-@contextlib.contextmanager
-def AutocommandEventsIgnored( events = [ 'all' ] ):
-  """Context manager to perform operations without triggering autocommand
-  events. |events| is a list of events to ignore. By default, all events are
-  ignored."""
-  old_eventignore = vim.options[ 'eventignore' ]
-  ignored_events = {
-    event for event in ToUnicode( old_eventignore ).split( ',' ) if event }
-  ignored_events.update( events )
-  vim.options[ 'eventignore' ] = ','.join( ignored_events )
-  try:
-    yield
-  finally:
-    vim.options[ 'eventignore' ] = old_eventignore
-
-
-def GetPreviousWindowNumber():
-  return GetIntValue( 'winnr("#")' ) - 1
-
-
-@contextlib.contextmanager
-def CurrentWindow():
-  """Context manager to perform operations on other windows than the current one
-  without triggering autocommands related to window movement. Use the
-  SwitchWindow function to move to other windows while under the context."""
-  previous_window = vim.windows[ GetPreviousWindowNumber() ]
-  current_window = vim.current.window
-  with AutocommandEventsIgnored( [ 'WinEnter', 'Winleave' ] ):
-    try:
-      yield
-    finally:
-      # Ensure <c-w>p still go to the previous window.
-      vim.current.window = previous_window
-      vim.current.window = current_window
-
-
-def SwitchWindow( window ):
-  """Move to the window object |window|. This function should be called under
-  the CurrentWindow context if you are going to switch back to the original
-  window."""
-  vim.current.window = window
-
-
 # Expects version_string in 'MAJOR.MINOR.PATCH' format, e.g. '8.1.278'
 def VimVersionAtLeast( version_string ):
   major, minor, patch = ( int( x ) for x in version_string.split( '.' ) )