WIP: Ability to ignore extra conf files

ycmd/completers/cpp/flags.py

@@ -28,6 +28,7 @@
                          CLANG_RESOURCE_DIR )
 from ycmd.responses import NoExtraConfDetected
 ycm_core = ImportCore()
+from ycmd.extra_conf_support import IgnoreExtraConf
 
 # -include-pch and --sysroot= must be listed before -include and --sysroot
 # respectively because the latter is a prefix of the former (and the algorithm
@@ -165,7 +166,10 @@ def _GetFlagsFromExtraConfOrDatabase( self, filename, client_data ):
     # Load the flags from the extra conf file if one is found and is not global.
     module = extra_conf_store.ModuleForSourceFile( filename )
     if module and not extra_conf_store.IsGlobalExtraConfModule( module ):
-      return _CallExtraConfFlagsForFile( module, filename, client_data )
+      try:
+        return _CallExtraConfFlagsForFile( module, filename, client_data )
+      except IgnoreExtraConf:
+        pass
 
     # Load the flags from the compilation database if any.
     database = self.LoadCompilationDatabase( filename )
@@ -174,7 +178,10 @@ def _GetFlagsFromExtraConfOrDatabase( self, filename, client_data ):
 
     # Load the flags from the global extra conf if set.
     if module:
-      return _CallExtraConfFlagsForFile( module, filename, client_data )
+      try:
+        return _CallExtraConfFlagsForFile( module, filename, client_data )
+      except IgnoreExtraConf:
+        pass
 
     # No compilation database and no extra conf found. Warn the user if not
     # already warned.

ycmd/completers/language_server/language_server_completer.py

@@ -30,6 +30,7 @@
 from ycmd.completers.completer import Completer, CompletionsCache
 from ycmd.completers.completer_utils import GetFileContents, GetFileLines
 from ycmd.utils import LOGGER
+from ycmd.extra_conf_support import IgnoreExtraConf
 
 from ycmd.completers.language_server import language_server_protocol as lsp
 
@@ -1416,10 +1417,14 @@ def DefaultSettings( self, request_data ):
 
   def GetSettings( self, module, request_data ):
     if hasattr( module, 'Settings' ):
-      settings = module.Settings(
-        language = self.Language(),
-        filename = request_data[ 'filepath' ],
-        client_data = request_data[ 'extra_conf_data' ] )
+      try:
+        settings = module.Settings(
+          language = self.Language(),
+          filename = request_data[ 'filepath' ],
+          client_data = request_data[ 'extra_conf_data' ] )
+      except IgnoreExtraConf:
+        settings = None
+
       if settings is not None:
         return settings
 

ycmd/completers/python/python_completer.py

@@ -16,6 +16,7 @@
 # along with ycmd.  If not, see <http://www.gnu.org/licenses/>.
 
 from ycmd import extra_conf_store, responses
+from ycmd.extra_conf_support import IgnoreExtraConf
 from ycmd.completers.completer import Completer, SignatureHelpAvailalability
 from ycmd.utils import ( CodepointOffsetToByteOffset,
                          ExpandVariablesInPath,
@@ -71,14 +72,18 @@ def _SettingsForRequest( self, request_data ):
 
   def _GetSettings( self, module, filepath, client_data ):
     # We don't warn the user if no extra conf file is found.
-    if module:
-      if hasattr( module, 'Settings' ):
-        settings = module.Settings( language = 'python',
-                                    filename = filepath,
-                                    client_data = client_data )
-        if settings is not None:
-          return settings
-      LOGGER.debug( 'No Settings function defined in %s', module.__file__ )
+    try:
+      if module:
+        if hasattr( module, 'Settings' ):
+          settings = module.Settings( language = 'python',
+                                      filename = filepath,
+                                      client_data = client_data )
+          if settings is not None:
+            return settings
+        LOGGER.debug( 'No Settings function defined in %s', module.__file__ )
+    except IgnoreExtraConf:
+      pass
+
     return {
       # NOTE: this option is only kept for backward compatibility. Setting the
       # Python interpreter path through the extra conf file is preferred.

ycmd/extra_conf_support.py

@@ -0,0 +1,46 @@
+# Copyright (C) 2011-2019 ycmd contributors
+#
+# This file is part of ycmd.
+#
+# ycmd is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# ycmd is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with ycmd.  If not, see <http://www.gnu.org/licenses/>.
+
+from __future__ import unicode_literals
+from __future__ import print_function
+from __future__ import division
+from __future__ import absolute_import
+# Not installing aliases from python-future; it's unreliable and slow.
+from builtins import *  # noqa
+
+
+class IgnoreExtraConf( Exception ):
+  """Raise this exception from within a FlagsForFile or Settings function to
+  instruct ycmd to ignore this module for the current file.
+
+  For example, if you wish to delegate to ycmd's built-in compilation database
+  support, you can write:
+
+    from ycmd.extra_conf_support import IgnoreExtraConf
+
+    def Settings( **kwargs ):
+      if kwargs[ 'language' ] == 'c-family':
+        # Use compilation database
+        raise IgnoreExtraConf()
+
+      if kwargs[ 'language' ] == 'python':
+        ...
+
+  This will then tell ycmd to use your compile_commands.json, or global extra
+  conf as if this local module doens't exist.
+  """
+  pass