Rewrite omnifunc tests

The VimBuffer object now accepts a Python function as its omnifunc.

python/ycm/tests/event_notification_test.py

@@ -361,7 +361,7 @@ def EventNotification_FileReadyToParse_TagFiles_UnicodeWorkingDirectory_test(
   with patch( 'ycm.client.event_notification.EventNotification.'
               'PostDataToHandlerAsync' ) as post_data_to_handler_async:
     with CurrentWorkingDirectory( unicode_dir ):
-      with MockVimBuffers( [ current_buffer ], current_buffer, ( 6, 5 ) ):
+      with MockVimBuffers( [ current_buffer ], current_buffer, ( 1, 5 ) ):
         ycm.OnFileReadyToParse()
 
     assert_that(
@@ -370,7 +370,7 @@ def EventNotification_FileReadyToParse_TagFiles_UnicodeWorkingDirectory_test(
       contains(
         has_entries( {
           'filepath': current_buffer_file,
-          'line_num': 6,
+          'line_num': 1,
           'column_num': 6,
           'file_data': has_entries( {
             current_buffer_file: has_entries( {
@@ -416,7 +416,7 @@ def EventNotification_BufferVisit_BuildRequestForCurrentAndUnsavedBuffers_test(
               'PostDataToHandlerAsync' ) as post_data_to_handler_async:
     with MockVimBuffers( [ current_buffer, modified_buffer, unmodified_buffer ],
                          current_buffer,
-                         ( 3, 5 ) ):
+                         ( 1, 5 ) ):
       ycm.OnBufferVisit()
 
     assert_that(
@@ -425,7 +425,7 @@ def EventNotification_BufferVisit_BuildRequestForCurrentAndUnsavedBuffers_test(
       contains(
         has_entries( {
           'filepath': current_buffer_file,
-          'line_num': 3,
+          'line_num': 1,
           'column_num': 6,
           'file_data': has_entries( {
             current_buffer_file: has_entries( {

python/ycm/tests/test_utils.py

@@ -23,6 +23,7 @@ from __future__ import absolute_import
 # Not installing aliases from python-future; it's unreliable and slow.
 from builtins import *  # noqa
 
+from future.utils import PY2
 from mock import MagicMock, patch
 from hamcrest import assert_that, equal_to
 import contextlib
@@ -32,7 +33,7 @@ import os
 import re
 import sys
 
-from ycmd.utils import GetCurrentDirectory, ToUnicode
+from ycmd.utils import GetCurrentDirectory, ToBytes, ToUnicode
 
 
 BUFNR_REGEX = re.compile( '^bufnr\(\'(?P<buffer_filename>.+)\', ([01])\)$' )
@@ -44,6 +45,8 @@ GETBUFVAR_REGEX = re.compile(
 MATCHADD_REGEX = re.compile(
   '^matchadd\(\'(?P<group>.+)\', \'(?P<pattern>.+)\'\)$' )
 MATCHDELETE_REGEX = re.compile( '^matchdelete\((?P<id>\d+)\)$' )
+OMNIFUNC_REGEX_FORMAT = (
+  '^{omnifunc_name}\((?P<findstart>[01]),[\'"](?P<base>.*)[\'"]\)$' )
 
 # One-and only instance of mocked Vim object. The first 'import vim' that is
 # executed binds the vim module to the instance of MagicMock that is created,
@@ -99,7 +102,7 @@ def _MockGetBufferVariable( buffer_number, option ):
 
 def _MockVimBufferEval( value ):
   if value == '&omnifunc':
-    return VIM_MOCK.current.buffer.omnifunc
+    return VIM_MOCK.current.buffer.omnifunc_name
 
   if value == '&filetype':
     return VIM_MOCK.current.buffer.filetype
@@ -120,6 +123,16 @@ def _MockVimBufferEval( value ):
     option = match.group( 'option' )
     return _MockGetBufferVariable( buffer_number, option )
 
+  current_buffer = VIM_MOCK.current.buffer
+  match = re.search( OMNIFUNC_REGEX_FORMAT.format(
+                         omnifunc_name = current_buffer.omnifunc_name ),
+                     value )
+  if match:
+    findstart = int( match.group( 'findstart' ) )
+    base = match.group( 'base' )
+    value = current_buffer.omnifunc( findstart, base )
+    return value if findstart else ToBytesOnPY2( value )
+
   return None
 
 
@@ -221,16 +234,24 @@ class VimBuffer( object ):
    - |modified| : True if the buffer has unsaved changes, False otherwise;
    - |bufhidden|: value of the 'bufhidden' option (see :h bufhidden);
    - |window|   : number of the buffer window. None if the buffer is hidden;
-   - |omnifunc| : omni completion function used by the buffer."""
+   - |omnifunc| : omni completion function used by the buffer. Must be a Python
+                  function that takes the same arguments and returns the same
+                  values as a Vim completion function (:h complete-functions).
+                  Example:
+
+                    def Omnifunc( findstart, base ):
+                      if findstart:
+                        return 5
+                      return [ 'a', 'b', 'c' ]"""
 
   def __init__( self, name,
                       number = 1,
-                      contents = [],
+                      contents = [ '' ],
                       filetype = '',
                       modified = False,
                       bufhidden = '',
                       window = None,
-                      omnifunc = '' ):
+                      omnifunc = None ):
     self.name = os.path.realpath( name ) if name else ''
     self.number = number
     self.contents = contents
@@ -239,6 +260,7 @@ class VimBuffer( object ):
     self.bufhidden = bufhidden
     self.window = window
     self.omnifunc = omnifunc
+    self.omnifunc_name = omnifunc.__name__ if omnifunc else ''
     self.changedtick = 1
 
 
@@ -292,9 +314,12 @@ def MockVimBuffers( buffers, current_buffer, cursor_position = ( 1, 1 ) ):
   if current_buffer not in buffers:
     raise RuntimeError( 'Current buffer must be part of the buffers list.' )
 
+  line = current_buffer.contents[ cursor_position[ 0 ] - 1 ]
+
   with patch( 'vim.buffers', buffers ):
     with patch( 'vim.current.buffer', current_buffer ):
       with patch( 'vim.current.window.cursor', cursor_position ):
+        with patch( 'vim.current.line', line ):
           yield VIM_MOCK
 
 
@@ -395,3 +420,20 @@ def ExpectedFailure( reason, *exception_matchers ):
     return Wrapper
 
   return decorator
+
+
+def ToBytesOnPY2( data ):
+  # To test the omnifunc, etc. returning strings, which can be of different
+  # types depending on python version, we use ToBytes on PY2 and just the native
+  # str on python3. This roughly matches what happens between py2 and py3
+  # versions within Vim.
+  if not PY2:
+    return data
+
+  if isinstance( data, list ):
+    return [ ToBytesOnPY2( item ) for item in data ]
+  if isinstance( data, dict ):
+    for item in data:
+      data[ item ] = ToBytesOnPY2( data[ item ] )
+    return data
+  return ToBytes( data )