Add current configurations from old repository

1 files changed, 1434 insertions, 0 deletions

diff --git a/vim/bundle/YouCompleteMe/python/ycm/tests/vimsupport_test.py b/vim/bundle/YouCompleteMe/python/ycm/tests/vimsupport_test.py
new file mode 100644
index 0000000..6840235
--- /dev/null
+++ b/vim/bundle/YouCompleteMe/python/ycm/tests/vimsupport_test.py
@@ -0,0 +1,1434 @@
+# coding: utf-8
+#
+# Copyright (C) 2015 YouCompleteMe contributors
+#
+# This file is part of YouCompleteMe.
+#
+# YouCompleteMe 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.
+#
+# YouCompleteMe 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 YouCompleteMe.  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
+from future import standard_library
+standard_library.install_aliases()
+from builtins import *  # noqa
+
+from ycm.test_utils import ExtendedMock, MockVimModule, MockVimCommand
+MockVimModule()
+
+from ycm import vimsupport
+from nose.tools import eq_
+from hamcrest import assert_that, calling, raises, none, has_entry
+from mock import MagicMock, call, patch
+from ycmd.utils import ToBytes, ToUnicode
+import os
+import json
+
+
+def ReplaceChunk_SingleLine_Repl_1_test():
+  # Replace with longer range
+  result_buffer = [ ToBytes( "This is a string" ) ]
+  start, end = _BuildLocations( 1, 1, 1, 5 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start,
+                                                          end,
+                                                          'How long',
+                                                          0,
+                                                          0,
+                                                          result_buffer )
+
+  eq_( [ ToBytes( "How long is a string" ) ], result_buffer )
+  eq_( line_offset, 0 )
+  eq_( char_offset, 4 )
+
+  # and replace again, using delta
+  start, end = _BuildLocations( 1, 10, 1, 11 )
+  ( new_line_offset, new_char_offset ) = vimsupport.ReplaceChunk(
+                                                          start,
+                                                          end,
+                                                          ' piece of ',
+                                                          line_offset,
+                                                          char_offset,
+                                                          result_buffer )
+
+  line_offset += new_line_offset
+  char_offset += new_char_offset
+
+  eq_( [ ToBytes( 'How long is a piece of string' ) ], result_buffer )
+  eq_( new_line_offset, 0 )
+  eq_( new_char_offset, 9 )
+  eq_( line_offset, 0 )
+  eq_( char_offset, 13 )
+
+  # and once more, for luck
+  start, end = _BuildLocations( 1, 11, 1, 17 )
+
+  ( new_line_offset, new_char_offset ) = vimsupport.ReplaceChunk(
+                                                          start,
+                                                          end,
+                                                          'pie',
+                                                          line_offset,
+                                                          char_offset,
+                                                          result_buffer )
+
+  line_offset += new_line_offset
+  char_offset += new_char_offset
+
+  eq_( [ ToBytes( 'How long is a piece of pie' ) ], result_buffer )
+  eq_( new_line_offset, 0 )
+  eq_( new_char_offset, -3 )
+  eq_( line_offset, 0 )
+  eq_( char_offset, 10 )
+
+
+def ReplaceChunk_SingleLine_Repl_2_test():
+  # Replace with shorter range
+  result_buffer = [ ToBytes( "This is a string" ) ]
+  start, end = _BuildLocations( 1, 11, 1, 17 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start,
+                                                          end,
+                                                          'test',
+                                                          0,
+                                                          0,
+                                                          result_buffer )
+
+  eq_( [ ToBytes( "This is a test" ) ], result_buffer )
+  eq_( line_offset, 0 )
+  eq_( char_offset, -2 )
+
+
+def ReplaceChunk_SingleLine_Repl_3_test():
+  # Replace with equal range
+  result_buffer = [ ToBytes( "This is a string" ) ]
+  start, end = _BuildLocations( 1, 6, 1, 8 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start,
+                                                          end,
+                                                          'be',
+                                                          0,
+                                                          0,
+                                                          result_buffer )
+
+  eq_( [ ToBytes( "This be a string" ) ], result_buffer )
+  eq_( line_offset, 0 )
+  eq_( char_offset, 0 )
+
+
+def ReplaceChunk_SingleLine_Add_1_test():
+  # Insert at start
+  result_buffer = [ ToBytes( "is a string" ) ]
+  start, end = _BuildLocations( 1, 1, 1, 1 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start,
+                                                          end,
+                                                          'This ',
+                                                          0,
+                                                          0,
+                                                          result_buffer )
+
+  eq_( [ ToBytes( "This is a string" ) ], result_buffer )
+  eq_( line_offset, 0 )
+  eq_( char_offset, 5 )
+
+
+def ReplaceChunk_SingleLine_Add_2_test():
+  # Insert at end
+  result_buffer = [ ToBytes( "This is a " ) ]
+  start, end = _BuildLocations( 1, 11, 1, 11 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start,
+                                                          end,
+                                                          'string',
+                                                          0,
+                                                          0,
+                                                          result_buffer )
+
+  eq_( [ ToBytes( "This is a string" ) ], result_buffer )
+  eq_( line_offset, 0 )
+  eq_( char_offset, 6 )
+
+
+def ReplaceChunk_SingleLine_Add_3_test():
+  # Insert in the middle
+  result_buffer = [ ToBytes( "This is a string" ) ]
+  start, end = _BuildLocations( 1, 8, 1, 8 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start,
+                                                          end,
+                                                          ' not',
+                                                          0,
+                                                          0,
+                                                          result_buffer )
+
+  eq_( [ ToBytes( "This is not a string" ) ], result_buffer )
+  eq_( line_offset, 0 )
+  eq_( char_offset, 4 )
+
+
+def ReplaceChunk_SingleLine_Del_1_test():
+  # Delete from start
+  result_buffer = [ ToBytes( "This is a string" ) ]
+  start, end = _BuildLocations( 1, 1, 1, 6 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start,
+                                                          end,
+                                                          '',
+                                                          0,
+                                                          0,
+                                                          result_buffer )
+
+  eq_( [ ToBytes( "is a string" ) ], result_buffer )
+  eq_( line_offset, 0 )
+  eq_( char_offset, -5 )
+
+
+def ReplaceChunk_SingleLine_Del_2_test():
+  # Delete from end
+  result_buffer = [ ToBytes( "This is a string" ) ]
+  start, end = _BuildLocations( 1, 10, 1, 18 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start,
+                                                          end,
+                                                          '',
+                                                          0,
+                                                          0,
+                                                          result_buffer )
+
+  eq_( [ ToBytes( "This is a" ) ], result_buffer )
+  eq_( line_offset, 0 )
+  eq_( char_offset, -8 )
+
+
+def ReplaceChunk_SingleLine_Del_3_test():
+  # Delete from middle
+  result_buffer = [ ToBytes( "This is not a string" ) ]
+  start, end = _BuildLocations( 1, 9, 1, 13 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start,
+                                                          end,
+                                                          '',
+                                                          0,
+                                                          0,
+                                                          result_buffer )
+
+  eq_( [ ToBytes( "This is a string" ) ], result_buffer )
+  eq_( line_offset, 0 )
+  eq_( char_offset, -4 )
+
+
+def ReplaceChunk_SingleLine_Unicode_ReplaceUnicodeChars_test():
+  # Replace Unicode characters.
+  result_buffer = [ ToBytes( "This Uniçø∂‰ string is in the middle" ) ]
+  start, end = _BuildLocations( 1, 6, 1, 20 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start,
+                                                          end,
+                                                          'Unicode ',
+                                                          0,
+                                                          0,
+                                                          result_buffer )
+
+  eq_( [ ToBytes( "This Unicode string is in the middle" ) ], result_buffer )
+  eq_( line_offset, 0 )
+  eq_( char_offset, -6 )
+
+
+def ReplaceChunk_SingleLine_Unicode_ReplaceAfterUnicode_test():
+  # Replace ASCII characters after Unicode characters in the line.
+  result_buffer = [ ToBytes( "This Uniçø∂‰ string is in the middle" ) ]
+  start, end = _BuildLocations( 1, 30, 1, 43 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start,
+                                                          end,
+                                                          'fåke',
+                                                          0,
+                                                          0,
+                                                          result_buffer )
+
+  eq_( [ ToBytes( "This Uniçø∂‰ string is fåke" ) ], result_buffer )
+  eq_( line_offset, 0 )
+  eq_( char_offset, -8 )
+
+
+def ReplaceChunk_SingleLine_Unicode_Grown_test():
+  # Replace ASCII characters after Unicode characters in the line.
+  result_buffer = [ ToBytes( "a" ) ]
+  start, end = _BuildLocations( 1, 1, 1, 2 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start,
+                                                          end,
+                                                          'å',
+                                                          0,
+                                                          0,
+                                                          result_buffer )
+
+  eq_( [ ToBytes( "å" ) ], result_buffer )
+  eq_( line_offset, 0 )
+  eq_( char_offset, 1 ) # Note: byte difference (a = 1 byte, å = 2 bytes)
+
+
+def ReplaceChunk_RemoveSingleLine_test():
+  result_buffer = [ ToBytes( "aAa" ),
+                    ToBytes( "aBa" ),
+                    ToBytes( "aCa" ) ]
+  start, end = _BuildLocations( 2, 1, 3, 1 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start, end, '',
+                                                          0, 0, result_buffer )
+  expected_buffer = [ ToBytes( "aAa" ),
+                      ToBytes( "aCa" ) ]
+  eq_( expected_buffer, result_buffer )
+  eq_( line_offset, -1 )
+  eq_( char_offset, 0 )
+
+
+def ReplaceChunk_SingleToMultipleLines_test():
+  result_buffer = [ ToBytes( "aAa" ),
+                    ToBytes( "aBa" ),
+                    ToBytes( "aCa" ) ]
+  start, end = _BuildLocations( 2, 2, 2, 2 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start, end, 'Eb\nbF',
+                                                          0, 0, result_buffer )
+  expected_buffer = [ ToBytes( "aAa" ),
+                      ToBytes( "aEb" ),
+                      ToBytes( "bFBa" ),
+                      ToBytes( "aCa" ) ]
+  eq_( expected_buffer, result_buffer )
+  eq_( line_offset, 1 )
+  eq_( char_offset, 1 )
+
+  # now make another change to the "2nd" line
+  start, end = _BuildLocations( 2, 3, 2, 4 )
+  ( new_line_offset, new_char_offset ) = vimsupport.ReplaceChunk(
+                                                           start,
+                                                           end,
+                                                           'cccc',
+                                                           line_offset,
+                                                           char_offset,
+                                                           result_buffer )
+
+  line_offset += new_line_offset
+  char_offset += new_char_offset
+
+  eq_( [ ToBytes( "aAa" ),
+         ToBytes( "aEb" ),
+         ToBytes( "bFBcccc" ),
+         ToBytes( "aCa" ) ], result_buffer )
+  eq_( line_offset, 1 )
+  eq_( char_offset, 4 )
+
+
+def ReplaceChunk_SingleToMultipleLines2_test():
+  result_buffer = [ ToBytes( "aAa" ), ToBytes( "aBa" ), ToBytes( "aCa" ) ]
+  start, end = _BuildLocations( 2, 2, 2, 2 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start,
+                                                          end,
+                                                          'Eb\nbFb\nG',
+                                                          0,
+                                                          0,
+                                                          result_buffer )
+  expected_buffer = [ ToBytes( "aAa" ),
+                      ToBytes( "aEb" ),
+                      ToBytes( "bFb" ),
+                      ToBytes( "GBa" ),
+                      ToBytes( "aCa" ) ]
+  eq_( expected_buffer, result_buffer )
+  eq_( line_offset, 2 )
+  eq_( char_offset, 0 )
+
+
+def ReplaceChunk_SingleToMultipleLines3_test():
+  result_buffer = [ ToBytes( "aAa" ), ToBytes( "aBa" ), ToBytes( "aCa" ) ]
+  start, end = _BuildLocations( 2, 2, 2, 2 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start,
+                                                          end,
+                                                          'Eb\nbFb\nbGb',
+                                                          0,
+                                                          0,
+                                                          result_buffer )
+  expected_buffer = [ ToBytes( "aAa" ),
+                      ToBytes( "aEb" ),
+                      ToBytes( "bFb" ),
+                      ToBytes( "bGbBa" ),
+                      ToBytes( "aCa" ) ]
+  eq_( expected_buffer, result_buffer )
+  eq_( line_offset, 2 )
+  eq_( char_offset, 2 )
+
+
+def ReplaceChunk_SingleToMultipleLinesReplace_test():
+  result_buffer = [ ToBytes( "aAa" ), ToBytes( "aBa" ), ToBytes( "aCa" ) ]
+  start, end = _BuildLocations( 1, 2, 1, 4 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start,
+                                                          end,
+                                                          'Eb\nbFb\nbGb',
+                                                          0,
+                                                          0,
+                                                          result_buffer )
+  expected_buffer = [ ToBytes( "aEb" ),
+                      ToBytes( "bFb" ),
+                      ToBytes( "bGb" ),
+                      ToBytes( "aBa" ),
+                      ToBytes( "aCa" ) ]
+  eq_( expected_buffer, result_buffer )
+  eq_( line_offset, 2 )
+  eq_( char_offset, 0 )
+
+
+def ReplaceChunk_SingleToMultipleLinesReplace_2_test():
+  result_buffer = [ ToBytes( "aAa" ),
+                    ToBytes( "aBa" ),
+                    ToBytes( "aCa" ) ]
+  start, end = _BuildLocations( 1, 2, 1, 4 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start,
+                                                          end,
+                                                          'Eb\nbFb\nbGb',
+                                                          0,
+                                                          0,
+                                                          result_buffer )
+  expected_buffer = [ ToBytes( "aEb" ),
+                      ToBytes( "bFb" ),
+                      ToBytes( "bGb" ),
+                      ToBytes( "aBa" ),
+                      ToBytes( "aCa" ) ]
+  eq_( expected_buffer, result_buffer )
+  eq_( line_offset, 2 )
+  eq_( char_offset, 0 )
+
+  # now do a subsequent change (insert at end of line "1")
+  start, end = _BuildLocations( 1, 4, 1, 4 )
+  ( new_line_offset, new_char_offset ) = vimsupport.ReplaceChunk(
+                                                          start,
+                                                          end,
+                                                          'cccc',
+                                                          line_offset,
+                                                          char_offset,
+                                                          result_buffer )
+
+  line_offset += new_line_offset
+  char_offset += new_char_offset
+
+  eq_( [ ToBytes( "aEb" ),
+         ToBytes( "bFb" ),
+         ToBytes( "bGbcccc" ),
+         ToBytes( "aBa" ),
+         ToBytes( "aCa" ) ], result_buffer )
+
+  eq_( line_offset, 2 )
+  eq_( char_offset, 4 )
+
+
+def ReplaceChunk_MultipleLinesToSingleLine_test():
+  result_buffer = [ ToBytes( "aAa" ), ToBytes( "aBa" ), ToBytes( "aCaaaa" ) ]
+  start, end = _BuildLocations( 2, 2, 3, 2 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start, end, 'E',
+                                                          0, 0, result_buffer )
+  expected_buffer = [ ToBytes( "aAa" ), ToBytes( "aECaaaa" ) ]
+  eq_( expected_buffer, result_buffer )
+  eq_( line_offset, -1 )
+  eq_( char_offset, 1 )
+
+  # make another modification applying offsets
+  start, end = _BuildLocations( 3, 3, 3, 4 )
+  ( new_line_offset, new_char_offset ) = vimsupport.ReplaceChunk(
+                                                          start,
+                                                          end,
+                                                          'cccc',
+                                                          line_offset,
+                                                          char_offset,
+                                                          result_buffer )
+
+  line_offset += new_line_offset
+  char_offset += new_char_offset
+
+  eq_( [ ToBytes( "aAa" ),
+         ToBytes( "aECccccaaa" ) ], result_buffer )
+  eq_( line_offset, -1 )
+  eq_( char_offset, 4 )
+
+  # and another, for luck
+  start, end = _BuildLocations( 3, 4, 3, 5 )
+  ( new_line_offset, new_char_offset ) = vimsupport.ReplaceChunk(
+                                                          start,
+                                                          end,
+                                                          'dd\ndd',
+                                                          line_offset,
+                                                          char_offset,
+                                                          result_buffer )
+
+  line_offset += new_line_offset
+  char_offset += new_char_offset
+
+  eq_( [ ToBytes( "aAa" ),
+         ToBytes( "aECccccdd" ),
+         ToBytes( "ddaa" ) ],
+       result_buffer )
+  eq_( line_offset, 0 )
+  eq_( char_offset, -2 )
+
+
+def ReplaceChunk_MultipleLinesToSameMultipleLines_test():
+  result_buffer = [ ToBytes( "aAa" ),
+                    ToBytes( "aBa" ),
+                    ToBytes( "aCa" ),
+                    ToBytes( "aDe" ) ]
+  start, end = _BuildLocations( 2, 2, 3, 2 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start, end, 'Eb\nbF',
+                                                          0, 0, result_buffer )
+  expected_buffer = [ ToBytes( "aAa" ),
+                      ToBytes( "aEb" ),
+                      ToBytes( "bFCa" ),
+                      ToBytes( "aDe" ) ]
+  eq_( expected_buffer, result_buffer )
+  eq_( line_offset, 0 )
+  eq_( char_offset, 1 )
+
+
+def ReplaceChunk_MultipleLinesToMoreMultipleLines_test():
+  result_buffer = [ ToBytes( "aAa" ),
+                    ToBytes( "aBa" ),
+                    ToBytes( "aCa" ),
+                    ToBytes( "aDe" ) ]
+  start, end = _BuildLocations( 2, 2, 3, 2 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start,
+                                                          end,
+                                                          'Eb\nbFb\nbG',
+                                                          0,
+                                                          0,
+                                                          result_buffer )
+  expected_buffer = [ ToBytes( "aAa" ),
+                      ToBytes( "aEb" ),
+                      ToBytes( "bFb" ),
+                      ToBytes( "bGCa" ),
+                      ToBytes( "aDe" ) ]
+  eq_( expected_buffer, result_buffer )
+  eq_( line_offset, 1 )
+  eq_( char_offset, 1 )
+
+
+def ReplaceChunk_MultipleLinesToLessMultipleLines_test():
+  result_buffer = [ ToBytes( "aAa" ),
+                    ToBytes( "aBa" ),
+                    ToBytes( "aCa" ),
+                    ToBytes( "aDe" ) ]
+  start, end = _BuildLocations( 1, 2, 3, 2 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start, end, 'Eb\nbF',
+                                                          0, 0, result_buffer )
+  expected_buffer = [ ToBytes( "aEb" ), ToBytes( "bFCa" ), ToBytes( "aDe" ) ]
+  eq_( expected_buffer, result_buffer )
+  eq_( line_offset, -1 )
+  eq_( char_offset, 1 )
+
+
+def ReplaceChunk_MultipleLinesToEvenLessMultipleLines_test():
+  result_buffer = [ ToBytes( "aAa" ),
+                    ToBytes( "aBa" ),
+                    ToBytes( "aCa" ),
+                    ToBytes( "aDe" ) ]
+  start, end = _BuildLocations( 1, 2, 4, 2 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start, end, 'Eb\nbF',
+                                                          0, 0, result_buffer )
+  expected_buffer = [ ToBytes( "aEb" ), ToBytes( "bFDe" ) ]
+  eq_( expected_buffer, result_buffer )
+  eq_( line_offset, -2 )
+  eq_( char_offset, 1 )
+
+
+def ReplaceChunk_SpanBufferEdge_test():
+  result_buffer = [ ToBytes( "aAa" ),
+                    ToBytes( "aBa" ),
+                    ToBytes( "aCa" ) ]
+  start, end = _BuildLocations( 1, 1, 1, 3 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start, end, 'bDb',
+                                                          0, 0, result_buffer )
+  expected_buffer = [ ToBytes( "bDba" ),
+                      ToBytes( "aBa" ),
+                      ToBytes( "aCa" ) ]
+  eq_( expected_buffer, result_buffer )
+  eq_( line_offset, 0 )
+  eq_( char_offset, 1 )
+
+
+def ReplaceChunk_DeleteTextInLine_test():
+  result_buffer = [ ToBytes( "aAa" ),
+                    ToBytes( "aBa" ),
+                    ToBytes( "aCa" ) ]
+  start, end = _BuildLocations( 2, 2, 2, 3 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start, end, '',
+                                                          0, 0, result_buffer )
+  expected_buffer = [ ToBytes( "aAa" ),
+                      ToBytes( "aa" ),
+                      ToBytes( "aCa" ) ]
+  eq_( expected_buffer, result_buffer )
+  eq_( line_offset, 0 )
+  eq_( char_offset, -1 )
+
+
+def ReplaceChunk_AddTextInLine_test():
+  result_buffer = [ ToBytes( "aAa" ),
+                    ToBytes( "aBa" ),
+                    ToBytes( "aCa" ) ]
+  start, end = _BuildLocations( 2, 2, 2, 2 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start, end, 'bDb',
+                                                          0, 0, result_buffer )
+  expected_buffer = [ ToBytes( "aAa" ),
+                      ToBytes( "abDbBa" ),
+                      ToBytes( "aCa" ) ]
+  eq_( expected_buffer, result_buffer )
+  eq_( line_offset, 0 )
+  eq_( char_offset, 3 )
+
+
+def ReplaceChunk_ReplaceTextInLine_test():
+  result_buffer = [ ToBytes( "aAa" ),
+                    ToBytes( "aBa" ),
+                    ToBytes( "aCa" ) ]
+  start, end = _BuildLocations( 2, 2, 2, 3 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start, end, 'bDb',
+                                                          0, 0, result_buffer )
+  expected_buffer = [ ToBytes( "aAa" ),
+                      ToBytes( "abDba" ),
+                      ToBytes( "aCa" ) ]
+  eq_( expected_buffer, result_buffer )
+  eq_( line_offset, 0 )
+  eq_( char_offset, 2 )
+
+
+def ReplaceChunk_SingleLineOffsetWorks_test():
+  result_buffer = [ ToBytes( "aAa" ),
+                    ToBytes( "aBa" ),
+                    ToBytes( "aCa" ) ]
+  start, end = _BuildLocations( 1, 1, 1, 2 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start, end, 'bDb',
+                                                          1, 1, result_buffer )
+  expected_buffer = [ ToBytes( "aAa" ),
+                      ToBytes( "abDba" ),
+                      ToBytes( "aCa" ) ]
+  eq_( expected_buffer, result_buffer )
+  eq_( line_offset, 0 )
+  eq_( char_offset, 2 )
+
+
+def ReplaceChunk_SingleLineToMultipleLinesOffsetWorks_test():
+  result_buffer = [ ToBytes( "aAa" ),
+                    ToBytes( "aBa" ),
+                    ToBytes( "aCa" ) ]
+  start, end = _BuildLocations( 1, 1, 1, 2 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start, end, 'Db\nE',
+                                                          1, 1, result_buffer )
+  expected_buffer = [ ToBytes( "aAa" ),
+                      ToBytes( "aDb" ),
+                      ToBytes( "Ea" ),
+                      ToBytes( "aCa" ) ]
+  eq_( expected_buffer, result_buffer )
+  eq_( line_offset, 1 )
+  eq_( char_offset, -1 )
+
+
+def ReplaceChunk_MultipleLinesToSingleLineOffsetWorks_test():
+  result_buffer = [ ToBytes( "aAa" ),
+                    ToBytes( "aBa" ),
+                    ToBytes( "aCa" ) ]
+  start, end = _BuildLocations( 1, 1, 2, 2 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start, end, 'bDb',
+                                                          1, 1, result_buffer )
+  expected_buffer = [ ToBytes( "aAa" ),
+                      ToBytes( "abDbCa" ) ]
+  eq_( expected_buffer, result_buffer )
+  eq_( line_offset, -1 )
+  eq_( char_offset, 3 )
+
+
+def ReplaceChunk_MultipleLineOffsetWorks_test():
+  result_buffer = [ ToBytes( "aAa" ),
+                    ToBytes( "aBa" ),
+                    ToBytes( "aCa" ) ]
+  start, end = _BuildLocations( 3, 1, 4, 3 )
+  ( line_offset, char_offset ) = vimsupport.ReplaceChunk( start,
+                                                          end,
+                                                          'bDb\nbEb\nbFb',
+                                                          -1,
+                                                          1,
+                                                          result_buffer )
+  expected_buffer = [ ToBytes( "aAa" ),
+                      ToBytes( "abDb" ),
+                      ToBytes( "bEb" ),
+                      ToBytes( "bFba" ) ]
+  eq_( expected_buffer, result_buffer )
+  eq_( line_offset, 1 )
+  eq_( char_offset, 1 )
+
+
+def _BuildLocations( start_line, start_column, end_line, end_column ):
+  return {
+    'line_num'  : start_line,
+    'column_num': start_column,
+  }, {
+    'line_num'  : end_line,
+    'column_num': end_column,
+  }
+
+
+def ReplaceChunksInBuffer_SortedChunks_test():
+  chunks = [
+    _BuildChunk( 1, 4, 1, 4, '('),
+    _BuildChunk( 1, 11, 1, 11, ')' )
+  ]
+
+  result_buffer = [ ToBytes( "CT<10 >> 2> ct" ) ]
+  vimsupport.ReplaceChunksInBuffer( chunks, result_buffer, None )
+
+  expected_buffer = [ ToBytes( "CT<(10 >> 2)> ct" ) ]
+  eq_( expected_buffer, result_buffer )
+
+
+def ReplaceChunksInBuffer_UnsortedChunks_test():
+  chunks = [
+    _BuildChunk( 1, 11, 1, 11, ')'),
+    _BuildChunk( 1, 4, 1, 4, '(' )
+  ]
+
+  result_buffer = [ ToBytes( "CT<10 >> 2> ct" ) ]
+  vimsupport.ReplaceChunksInBuffer( chunks, result_buffer, None )
+
+  expected_buffer = [ ToBytes( "CT<(10 >> 2)> ct" ) ]
+  eq_( expected_buffer, result_buffer )
+
+
+class MockBuffer( object ):
+  """An object that looks like a vim.buffer object, enough for ReplaceChunk to
+  generate a location list"""
+
+  def __init__( self, lines, name, number ):
+    self.lines = [ ToBytes( x ) for x in lines ]
+    self.name = name
+    self.number = number
+
+
+  def __getitem__( self, index ):
+    """ Return the bytes for a given line at index |index| """
+    return self.lines[ index ]
+
+
+  def __len__( self ):
+    return len( self.lines )
+
+
+  def __setitem__( self, key, value ):
+    return self.lines.__setitem__( key, value )
+
+
+  def GetLines( self ):
+    """ Return the contents of the buffer as a list of unicode strings"""
+    return [ ToUnicode( x ) for x in self.lines ]
+
+
+@patch( 'ycm.vimsupport.VariableExists', return_value = False )
+@patch( 'ycm.vimsupport.SetFittingHeightForCurrentWindow' )
+@patch( 'ycm.vimsupport.GetBufferNumberForFilename',
+        return_value=1,
+        new_callable=ExtendedMock )
+@patch( 'ycm.vimsupport.BufferIsVisible',
+        return_value=True,
+        new_callable=ExtendedMock )
+@patch( 'ycm.vimsupport.OpenFilename' )
+@patch( 'ycm.vimsupport.EchoTextVimWidth', new_callable=ExtendedMock )
+@patch( 'vim.eval', new_callable=ExtendedMock )
+@patch( 'vim.command', new_callable=ExtendedMock )
+def ReplaceChunks_SingleFile_Open_test( vim_command,
+                                        vim_eval,
+                                        echo_text_vim_width,
+                                        open_filename,
+                                        buffer_is_visible,
+                                        get_buffer_number_for_filename,
+                                        set_fitting_height,
+                                        variable_exists ):
+
+  chunks = [
+    _BuildChunk( 1, 1, 2, 1, 'replacement', 'single_file' )
+  ]
+
+  result_buffer = MockBuffer( [
+    'line1',
+    'line2',
+    'line3',
+  ], 'single_file', 1 )
+
+  with patch( 'vim.buffers', [ None, result_buffer, None ] ):
+    vimsupport.ReplaceChunks( chunks )
+
+  # Ensure that we applied the replacement correctly
+  eq_( result_buffer.GetLines(), [
+    'replacementline2',
+    'line3',
+  ] )
+
+  # GetBufferNumberForFilename is called twice:
+  #  - once to the check if we would require opening the file (so that we can
+  #    raise a warning)
+  #  - once whilst applying the changes
+  get_buffer_number_for_filename.assert_has_exact_calls( [
+      call( 'single_file', False ),
+      call( 'single_file', False ),
+  ] )
+
+  # BufferIsVisible is called twice for the same reasons as above
+  buffer_is_visible.assert_has_exact_calls( [
+      call( 1 ),
+      call( 1 ),
+  ] )
+
+  # we don't attempt to open any files
+  open_filename.assert_not_called()
+
+  # But we do set the quickfix list
+  vim_eval.assert_has_exact_calls( [
+      call( 'setqflist( {0} )'.format( json.dumps( [ {
+        'bufnr': 1,
+        'filename': 'single_file',
+        'lnum': 1,
+        'col': 1,
+        'text': 'replacement',
+        'type': 'F'
+      } ] ) ) ),
+  ] )
+  vim_command.assert_has_exact_calls( [
+      call( 'botright copen' ),
+      call( 'silent! wincmd p' )
+  ] )
+  set_fitting_height.assert_called_once_with()
+
+  # And it is ReplaceChunks that prints the message showing the number of
+  # changes
+  echo_text_vim_width.assert_has_exact_calls( [
+      call( 'Applied 1 changes' ),
+  ] )
+
+
+@patch( 'ycm.vimsupport.VariableExists', return_value = False )
+@patch( 'ycm.vimsupport.SetFittingHeightForCurrentWindow' )
+@patch( 'ycm.vimsupport.GetBufferNumberForFilename',
+        side_effect=[ -1, -1, 1 ],
+        new_callable=ExtendedMock )
+@patch( 'ycm.vimsupport.BufferIsVisible',
+        side_effect=[ False, False, True ],
+        new_callable=ExtendedMock )
+@patch( 'ycm.vimsupport.OpenFilename',
+        new_callable=ExtendedMock )
+@patch( 'ycm.vimsupport.EchoTextVimWidth', new_callable=ExtendedMock )
+@patch( 'ycm.vimsupport.Confirm',
+        return_value=True,
+        new_callable=ExtendedMock )
+@patch( 'vim.eval', return_value=10, new_callable=ExtendedMock )
+@patch( 'vim.command', new_callable=ExtendedMock )
+def ReplaceChunks_SingleFile_NotOpen_test( vim_command,
+                                           vim_eval,
+                                           confirm,
+                                           echo_text_vim_width,
+                                           open_filename,
+                                           buffer_is_visible,
+                                           get_buffer_number_for_filename,
+                                           set_fitting_height,
+                                           variable_exists ):
+
+  chunks = [
+    _BuildChunk( 1, 1, 2, 1, 'replacement', 'single_file' )
+  ]
+
+  result_buffer = MockBuffer( [
+    'line1',
+    'line2',
+    'line3',
+  ], 'single_file', 1 )
+
+  with patch( 'vim.buffers', [ None, result_buffer, None ] ):
+    vimsupport.ReplaceChunks( chunks )
+
+  # We checked if it was OK to open the file
+  confirm.assert_has_exact_calls( [
+    call( vimsupport.FIXIT_OPENING_BUFFERS_MESSAGE_FORMAT.format( 1 ) )
+  ] )
+
+  # Ensure that we applied the replacement correctly
+  eq_( result_buffer.GetLines(), [
+    'replacementline2',
+    'line3',
+  ] )
+
+  # GetBufferNumberForFilename is called 3 times. The return values are set in
+  # the @patch call above:
+  #  - once to the check if we would require opening the file (so that we can
+  #    raise a warning) (-1 return)
+  #  - once whilst applying the changes (-1 return)
+  #  - finally after calling OpenFilename (1 return)
+  get_buffer_number_for_filename.assert_has_exact_calls( [
+      call( 'single_file', False ),
+      call( 'single_file', False ),
+      call( 'single_file', False ),
+  ] )
+
+  # BufferIsVisible is called 3 times for the same reasons as above, with the
+  # return of each one
+  buffer_is_visible.assert_has_exact_calls( [
+    call( -1 ),
+    call( -1 ),
+    call( 1 ),
+  ] )
+
+  # We open 'single_file' as expected.
+  open_filename.assert_called_with( 'single_file', {
+    'focus': True,
+    'fix': True,
+    'size': 10
+  } )
+
+  # And close it again, then show the quickfix window.
+  vim_command.assert_has_exact_calls( [
+    call( 'lclose' ),
+    call( 'hide' ),
+    call( 'botright copen' ),
+    call( 'silent! wincmd p' )
+  ] )
+  set_fitting_height.assert_called_once_with()
+
+  # And update the quickfix list
+  vim_eval.assert_has_exact_calls( [
+    call( '&previewheight' ),
+    call( 'setqflist( {0} )'.format( json.dumps( [ {
+      'bufnr': 1,
+      'filename': 'single_file',
+      'lnum': 1,
+      'col': 1,
+      'text': 'replacement',
+      'type': 'F'
+    } ] ) ) ),
+  ] )
+
+  # And it is ReplaceChunks that prints the message showing the number of
+  # changes
+  echo_text_vim_width.assert_has_exact_calls( [
+    call( 'Applied 1 changes' ),
+  ] )
+
+
+@patch( 'ycm.vimsupport.GetBufferNumberForFilename',
+        side_effect=[ -1, -1, 1 ],
+        new_callable=ExtendedMock )
+@patch( 'ycm.vimsupport.BufferIsVisible',
+        side_effect=[ False, False, True ],
+        new_callable=ExtendedMock )
+@patch( 'ycm.vimsupport.OpenFilename',
+        new_callable=ExtendedMock )
+@patch( 'ycm.vimsupport.EchoTextVimWidth',
+        new_callable=ExtendedMock )
+@patch( 'ycm.vimsupport.Confirm',
+        return_value=False,
+        new_callable=ExtendedMock )
+@patch( 'vim.eval',
+        return_value=10,
+        new_callable=ExtendedMock )
+@patch( 'vim.command', new_callable=ExtendedMock )
+def ReplaceChunks_User_Declines_To_Open_File_test(
+                                           vim_command,
+                                           vim_eval,
+                                           confirm,
+                                           echo_text_vim_width,
+                                           open_filename,
+                                           buffer_is_visible,
+                                           get_buffer_number_for_filename ):
+
+  # Same as above, except the user selects Cancel when asked if they should
+  # allow us to open lots of (ahem, 1) file.
+
+  chunks = [
+    _BuildChunk( 1, 1, 2, 1, 'replacement', 'single_file' )
+  ]
+
+  result_buffer = MockBuffer( [
+    'line1',
+    'line2',
+    'line3',
+  ], 'single_file', 1 )
+
+  with patch( 'vim.buffers', [ None, result_buffer, None ] ):
+    vimsupport.ReplaceChunks( chunks )
+
+  # We checked if it was OK to open the file
+  confirm.assert_has_exact_calls( [
+    call( vimsupport.FIXIT_OPENING_BUFFERS_MESSAGE_FORMAT.format( 1 ) )
+  ] )
+
+  # Ensure that buffer is not changed
+  eq_( result_buffer.GetLines(), [
+    'line1',
+    'line2',
+    'line3',
+  ] )
+
+  # GetBufferNumberForFilename is called once. The return values are set in
+  # the @patch call above:
+  #  - once to the check if we would require opening the file (so that we can
+  #    raise a warning) (-1 return)
+  get_buffer_number_for_filename.assert_has_exact_calls( [
+      call( 'single_file', False ),
+  ] )
+
+  # BufferIsVisible is called once for the above file, which wasn't visible.
+  buffer_is_visible.assert_has_exact_calls( [
+    call( -1 ),
+  ] )
+
+  # We don't attempt to open any files or update any quickfix list or anything
+  # like that
+  open_filename.assert_not_called()
+  vim_eval.assert_not_called()
+  vim_command.assert_not_called()
+  echo_text_vim_width.assert_not_called()
+
+
+@patch( 'ycm.vimsupport.GetBufferNumberForFilename',
+        side_effect=[ -1, -1, 1 ],
+        new_callable=ExtendedMock )
+# Key difference is here: In the final check, BufferIsVisible returns False
+@patch( 'ycm.vimsupport.BufferIsVisible',
+        side_effect=[ False, False, False ],
+        new_callable=ExtendedMock )
+@patch( 'ycm.vimsupport.OpenFilename',
+        new_callable=ExtendedMock )
+@patch( 'ycm.vimsupport.EchoTextVimWidth',
+        new_callable=ExtendedMock )
+@patch( 'ycm.vimsupport.Confirm',
+        return_value=True,
+        new_callable=ExtendedMock )
+@patch( 'vim.eval',
+        return_value=10,
+        new_callable=ExtendedMock )
+@patch( 'vim.command',
+        new_callable=ExtendedMock )
+def ReplaceChunks_User_Aborts_Opening_File_test(
+                                           vim_command,
+                                           vim_eval,
+                                           confirm,
+                                           echo_text_vim_width,
+                                           open_filename,
+                                           buffer_is_visible,
+                                           get_buffer_number_for_filename ):
+
+  # Same as above, except the user selects Abort or Quick during the
+  # "swap-file-found" dialog
+
+  chunks = [
+    _BuildChunk( 1, 1, 2, 1, 'replacement', 'single_file' )
+  ]
+
+  result_buffer = MockBuffer( [
+    'line1',
+    'line2',
+    'line3',
+  ], 'single_file', 1 )
+
+  with patch( 'vim.buffers', [ None, result_buffer, None ] ):
+    assert_that( calling( vimsupport.ReplaceChunks ).with_args( chunks ),
+                 raises( RuntimeError,
+                  'Unable to open file: single_file\nFixIt/Refactor operation '
+                  'aborted prior to completion. Your files have not been '
+                  'fully updated. Please use undo commands to revert the '
+                  'applied changes.' ) )
+
+  # We checked if it was OK to open the file
+  confirm.assert_has_exact_calls( [
+    call( vimsupport.FIXIT_OPENING_BUFFERS_MESSAGE_FORMAT.format( 1 ) )
+  ] )
+
+  # Ensure that buffer is not changed
+  eq_( result_buffer.GetLines(), [
+    'line1',
+    'line2',
+    'line3',
+  ] )
+
+  # We tried to open this file
+  open_filename.assert_called_with( "single_file", {
+    'focus': True,
+    'fix': True,
+    'size': 10
+  } )
+  vim_eval.assert_called_with( "&previewheight" )
+
+  # But raised an exception before issuing the message at the end
+  echo_text_vim_width.assert_not_called()
+
+
+@patch( 'ycm.vimsupport.VariableExists', return_value = False )
+@patch( 'ycm.vimsupport.SetFittingHeightForCurrentWindow' )
+@patch( 'ycm.vimsupport.GetBufferNumberForFilename', side_effect=[
+          22, # first_file (check)
+          -1, # another_file (check)
+          22, # first_file (apply)
+          -1, # another_file (apply)
+          19, # another_file (check after open)
+        ],
+        new_callable=ExtendedMock )
+@patch( 'ycm.vimsupport.BufferIsVisible', side_effect=[
+          True,  # first_file (check)
+          False, # second_file (check)
+          True,  # first_file (apply)
+          False, # second_file (apply)
+          True,  # side_effect (check after open)
+        ],
+        new_callable=ExtendedMock)
+@patch( 'ycm.vimsupport.OpenFilename',
+        new_callable=ExtendedMock)
+@patch( 'ycm.vimsupport.EchoTextVimWidth',
+        new_callable=ExtendedMock)
+@patch( 'ycm.vimsupport.Confirm', return_value=True,
+        new_callable=ExtendedMock)
+@patch( 'vim.eval', return_value=10,
+        new_callable=ExtendedMock)
+@patch( 'vim.command',
+        new_callable=ExtendedMock)
+def ReplaceChunks_MultiFile_Open_test( vim_command,
+                                       vim_eval,
+                                       confirm,
+                                       echo_text_vim_width,
+                                       open_filename,
+                                       buffer_is_visible,
+                                       get_buffer_number_for_filename,
+                                       set_fitting_height,
+                                       variable_exists ):
+
+  # Chunks are split across 2 files, one is already open, one isn't
+
+  chunks = [
+    _BuildChunk( 1, 1, 2, 1, 'first_file_replacement ', '1_first_file' ),
+    _BuildChunk( 2, 1, 2, 1, 'second_file_replacement ', '2_another_file' ),
+  ]
+
+  first_file = MockBuffer( [
+    'line1',
+    'line2',
+    'line3',
+  ], '1_first_file', 22 )
+  another_file = MockBuffer( [
+    'another line1',
+    'ACME line2',
+  ], '2_another_file', 19 )
+
+  vim_buffers = [ None ] * 23
+  vim_buffers[ 22 ] = first_file
+  vim_buffers[ 19 ] = another_file
+
+  with patch( 'vim.buffers', vim_buffers ):
+    vimsupport.ReplaceChunks( chunks )
+
+  # We checked for the right file names
+  get_buffer_number_for_filename.assert_has_exact_calls( [
+    call( '1_first_file', False ),
+    call( '2_another_file', False ),
+    call( '1_first_file', False ),
+    call( '2_another_file', False ),
+    call( '2_another_file', False ),
+  ] )
+
+  # We checked if it was OK to open the file
+  confirm.assert_has_exact_calls( [
+    call( vimsupport.FIXIT_OPENING_BUFFERS_MESSAGE_FORMAT.format( 1 ) )
+  ] )
+
+  # Ensure that buffers are updated
+  eq_( another_file.GetLines(), [
+    'another line1',
+    'second_file_replacement ACME line2',
+  ] )
+  eq_( first_file.GetLines(), [
+    'first_file_replacement line2',
+    'line3',
+  ] )
+
+  # We open '2_another_file' as expected.
+  open_filename.assert_called_with( '2_another_file', {
+    'focus': True,
+    'fix': True,
+    'size': 10
+  } )
+
+  # And close it again, then show the quickfix window.
+  vim_command.assert_has_exact_calls( [
+    call( 'lclose' ),
+    call( 'hide' ),
+    call( 'botright copen' ),
+    call( 'silent! wincmd p' )
+  ] )
+  set_fitting_height.assert_called_once_with()
+
+  # And update the quickfix list with each entry
+  vim_eval.assert_has_exact_calls( [
+    call( '&previewheight' ),
+    call( 'setqflist( {0} )'.format( json.dumps( [ {
+      'bufnr': 22,
+      'filename': '1_first_file',
+      'lnum': 1,
+      'col': 1,
+      'text': 'first_file_replacement ',
+      'type': 'F'
+    }, {
+      'bufnr': 19,
+      'filename': '2_another_file',
+      'lnum': 2,
+      'col': 1,
+      'text': 'second_file_replacement ',
+      'type': 'F'
+    } ] ) ) ),
+  ] )
+
+  # And it is ReplaceChunks that prints the message showing the number of
+  # changes
+  echo_text_vim_width.assert_has_exact_calls( [
+    call( 'Applied 2 changes' ),
+  ] )
+
+
+def _BuildChunk( start_line,
+                 start_column,
+                 end_line,
+                 end_column,
+                 replacement_text, filepath='test_file_name' ):
+  return {
+    'range': {
+      'start': {
+        'filepath': filepath,
+        'line_num': start_line,
+        'column_num': start_column,
+      },
+      'end': {
+        'filepath': filepath,
+        'line_num': end_line,
+        'column_num': end_column,
+      },
+    },
+    'replacement_text': replacement_text
+  }
+
+
+@patch( 'vim.command', new_callable=ExtendedMock )
+@patch( 'vim.current', new_callable=ExtendedMock)
+def WriteToPreviewWindow_test( vim_current, vim_command ):
+  vim_current.window.options.__getitem__ = MagicMock( return_value = True )
+
+  vimsupport.WriteToPreviewWindow( "test" )
+
+  vim_command.assert_has_exact_calls( [
+    call( 'silent! pclose!' ),
+    call( 'silent! pedit! _TEMP_FILE_' ),
+    call( 'silent! wincmd P' ),
+    call( 'silent! wincmd p' ) ] )
+
+  vim_current.buffer.__setitem__.assert_called_with(
+      slice( None, None, None ), [ 'test' ] )
+
+  vim_current.buffer.options.__setitem__.assert_has_exact_calls( [
+    call( 'modifiable', True ),
+    call( 'readonly', False ),
+    call( 'buftype', 'nofile' ),
+    call( 'swapfile', False ),
+    call( 'modifiable', False ),
+    call( 'modified', False ),
+    call( 'readonly', True ),
+  ], any_order = True )
+
+
+@patch( 'vim.current' )
+def WriteToPreviewWindow_MultiLine_test( vim_current ):
+  vim_current.window.options.__getitem__ = MagicMock( return_value = True )
+  vimsupport.WriteToPreviewWindow( "test\ntest2" )
+
+  vim_current.buffer.__setitem__.assert_called_with(
+      slice( None, None, None ), [ 'test', 'test2' ] )
+
+
+@patch( 'vim.command', new_callable=ExtendedMock )
+@patch( 'vim.current', new_callable=ExtendedMock )
+def WriteToPreviewWindow_JumpFail_test( vim_current, vim_command ):
+  vim_current.window.options.__getitem__ = MagicMock( return_value = False )
+
+  vimsupport.WriteToPreviewWindow( "test" )
+
+  vim_command.assert_has_exact_calls( [
+    call( 'silent! pclose!' ),
+    call( 'silent! pedit! _TEMP_FILE_' ),
+    call( 'silent! wincmd P' ),
+    call( "echom 'test'" ),
+  ] )
+
+  vim_current.buffer.__setitem__.assert_not_called()
+  vim_current.buffer.options.__setitem__.assert_not_called()
+
+
+@patch( 'vim.command', new_callable=ExtendedMock )
+@patch( 'vim.current', new_callable=ExtendedMock )
+def WriteToPreviewWindow_JumpFail_MultiLine_test( vim_current, vim_command ):
+
+  vim_current.window.options.__getitem__ = MagicMock( return_value = False )
+
+  vimsupport.WriteToPreviewWindow( "test\ntest2" )
+
+  vim_command.assert_has_exact_calls( [
+    call( 'silent! pclose!' ),
+    call( 'silent! pedit! _TEMP_FILE_' ),
+    call( 'silent! wincmd P' ),
+    call( "echom 'test'" ),
+    call( "echom 'test2'" ),
+  ] )
+
+  vim_current.buffer.__setitem__.assert_not_called()
+  vim_current.buffer.options.__setitem__.assert_not_called()
+
+
+def CheckFilename_test():
+  assert_that(
+    calling( vimsupport.CheckFilename ).with_args( None ),
+    raises( RuntimeError, "'None' is not a valid filename" )
+  )
+
+  assert_that(
+    calling( vimsupport.CheckFilename ).with_args( 'nonexistent_file' ),
+    raises( RuntimeError,
+            "filename 'nonexistent_file' cannot be opened. "
+            "No such file or directory." )
+  )
+
+  assert_that( vimsupport.CheckFilename( __file__ ), none() )
+
+
+def BufferIsVisibleForFilename_test():
+  buffers = [
+    {
+      'number': 1,
+      'filename': os.path.realpath( 'visible_filename' ),
+      'window': 1
+    },
+    {
+      'number': 2,
+      'filename': os.path.realpath( 'hidden_filename' ),
+    }
+  ]
+
+  with patch( 'vim.buffers', buffers ):
+    eq_( vimsupport.BufferIsVisibleForFilename( 'visible_filename' ), True )
+    eq_( vimsupport.BufferIsVisibleForFilename( 'hidden_filename' ), False )
+    eq_( vimsupport.BufferIsVisibleForFilename( 'another_filename' ), False )
+
+
+@patch( 'ycm.vimsupport.GetBufferNumberForFilename',
+        side_effect = [ 2, 5, -1 ] )
+@patch( 'vim.command',
+        side_effect = MockVimCommand,
+        new_callable = ExtendedMock )
+def CloseBuffersForFilename_test( vim_command, *args ):
+  vimsupport.CloseBuffersForFilename( 'some_filename' )
+
+  vim_command.assert_has_exact_calls( [
+    call( 'silent! bwipeout! 2' ),
+    call( 'silent! bwipeout! 5' )
+  ], any_order = True )
+
+
+@patch( 'vim.command', new_callable = ExtendedMock )
+@patch( 'vim.current', new_callable = ExtendedMock )
+def OpenFilename_test( vim_current, vim_command ):
+  # Options used to open a logfile
+  options = {
+    'size': vimsupport.GetIntValue( '&previewheight' ),
+    'fix': True,
+    'watch': True,
+    'position': 'end'
+  }
+
+  vimsupport.OpenFilename( __file__, options )
+
+  vim_command.assert_has_exact_calls( [
+    call( '12split {0}'.format( __file__ ) ),
+    call( "exec "
+          "'au BufEnter <buffer> :silent! checktime {0}'".format( __file__ ) ),
+    call( 'silent! normal G zz' ),
+    call( 'silent! wincmd p' )
+  ] )
+
+  vim_current.buffer.options.__setitem__.assert_has_exact_calls( [
+    call( 'autoread', True ),
+  ] )
+
+  vim_current.window.options.__setitem__.assert_has_exact_calls( [
+    call( 'winfixheight', True )
+  ] )
+
+
+@patch( 'ycm.vimsupport.BufferModified', side_effect = [ True ] )
+@patch( 'ycm.vimsupport.FiletypesForBuffer', side_effect = [ [ 'cpp' ] ] )
+def GetUnsavedAndCurrentBufferData_EncodedUnicodeCharsInBuffers_test( *args ):
+  mock_buffer = MagicMock()
+  mock_buffer.name = os.path.realpath( 'filename' )
+  mock_buffer.number = 1
+  mock_buffer.__iter__.return_value = [ u'abc', ToBytes( u'fДa' ) ]
+
+  with patch( 'vim.buffers', [ mock_buffer ] ):
+    assert_that( vimsupport.GetUnsavedAndCurrentBufferData(),
+                 has_entry( mock_buffer.name,
+                            has_entry( u'contents', u'abc\nfДa\n' ) ) )
+
+
+# NOTE: Vim returns byte offsets for columns, not actual character columns. This
+# makes 'ДД' have 4 columns: column 0, column 2 and column 4.
+@patch( 'vim.current.line', ToBytes( 'ДДaa' ) )
+@patch( 'ycm.vimsupport.CurrentColumn', side_effect = [ 4 ] )
+def TextBeforeCursor_EncodedUnicode_test( *args ):
+  eq_( vimsupport.TextBeforeCursor(), u'ДД' )
+
+
+# NOTE: Vim returns byte offsets for columns, not actual character columns. This
+# makes 'ДД' have 4 columns: column 0, column 2 and column 4.
+@patch( 'vim.current.line', ToBytes( 'aaДД' ) )
+@patch( 'ycm.vimsupport.CurrentColumn', side_effect = [ 2 ] )
+def TextAfterCursor_EncodedUnicode_test( *args ):
+  eq_( vimsupport.TextAfterCursor(), u'ДД' )
+
+
+@patch( 'vim.current.line', ToBytes( 'fДa' ) )
+def CurrentLineContents_EncodedUnicode_test( *args ):
+  eq_( vimsupport.CurrentLineContents(), u'fДa' )
+
+
+@patch( 'vim.eval', side_effect = lambda x: x )
+def VimExpressionToPythonType_IntAsUnicode_test( *args ):
+  eq_( vimsupport.VimExpressionToPythonType( '123' ), 123 )
+
+
+@patch( 'vim.eval', side_effect = lambda x: x )
+def VimExpressionToPythonType_IntAsBytes_test( *args ):
+  eq_( vimsupport.VimExpressionToPythonType( ToBytes( '123' ) ), 123 )
+
+
+@patch( 'vim.eval', side_effect = lambda x: x )
+def VimExpressionToPythonType_StringAsUnicode_test( *args ):
+  eq_( vimsupport.VimExpressionToPythonType( 'foo' ), 'foo' )
+
+
+@patch( 'vim.eval', side_effect = lambda x: x )
+def VimExpressionToPythonType_StringAsBytes_test( *args ):
+  eq_( vimsupport.VimExpressionToPythonType( ToBytes( 'foo' ) ), 'foo' )
+
+
+@patch( 'vim.eval', side_effect = lambda x: x )
+def VimExpressionToPythonType_ListPassthrough_test( *args ):
+  eq_( vimsupport.VimExpressionToPythonType( [ 1, 2 ] ), [ 1, 2 ] )
+
+
+@patch( 'vim.eval', side_effect = lambda x: x )
+def VimExpressionToPythonType_ObjectPassthrough_test( *args ):
+  eq_( vimsupport.VimExpressionToPythonType( { 1: 2 } ), { 1: 2 } )
+
+
+@patch( 'vim.eval', side_effect = lambda x: x )
+def VimExpressionToPythonType_GeneratorPassthrough_test( *args ):
+  gen = ( x**2 for x in [ 1, 2, 3 ] )
+  eq_( vimsupport.VimExpressionToPythonType( gen ), gen )