diff --git a/pythonx/UltiSnips/_vim.py b/pythonx/UltiSnips/_vim.py
index 59188e3..162a225 100755
--- a/pythonx/UltiSnips/_vim.py
+++ b/pythonx/UltiSnips/_vim.py
@@ -75,8 +75,8 @@ class VimBuffer(object):
 buf = VimBuffer()  # pylint:disable=invalid-name
 
 @contextmanager
-def toggle_opt(name, new_value):
-    old_value = eval('&' + name)
+def option_set_to(name, new_value):
+    old_value = vim.eval('&' + name)
     command('set {0}={1}'.format(name, new_value))
     try:
         yield
diff --git a/pythonx/UltiSnips/snippet/definition/_base.py b/pythonx/UltiSnips/snippet/definition/_base.py
index e8ece6b..4106ac3 100644
--- a/pythonx/UltiSnips/snippet/definition/_base.py
+++ b/pythonx/UltiSnips/snippet/definition/_base.py
@@ -13,12 +13,47 @@ from UltiSnips.compatibility import as_unicode
 from UltiSnips.indent_util import IndentUtil
 from UltiSnips.text import escape
 from UltiSnips.text_objects import SnippetInstance
-from UltiSnips.text_objects._python_code import \
-    SnippetUtilCursor, SnippetUtilForAction
+from UltiSnips.text_objects._python_code import SnippetUtilForAction
 
 __WHITESPACE_SPLIT = re.compile(r"\s")
 
 
+class _SnippetUtilCursor(object):
+    def __init__(self, cursor):
+        self._cursor = [cursor[0] - 1, cursor[1]]
+        self._set = False
+
+    def preserve(self):
+        self._set = True
+        self._cursor = [
+            _vim.buf.cursor[0],
+            _vim.buf.cursor[1],
+        ]
+
+    def is_set(self):
+        return self._set
+
+    def set(self, line, column):
+        self.__setitem__(0, line)
+        self.__setitem__(1, column)
+
+    def to_vim_cursor(self):
+        return (self._cursor[0] + 1, self._cursor[1])
+
+    def __getitem__(self, index):
+        return self._cursor[index]
+
+    def __setitem__(self, index, value):
+        self._set = True
+        self._cursor[index] = value
+
+    def __len__(self):
+        return 2
+
+    def __str__(self):
+        return str((self._cursor[0], self._cursor[1]))
+
+
 def split_at_whitespace(string):
     """Like string.split(), but keeps empty words as empty words."""
     return re.split(__WHITESPACE_SPLIT, string)
@@ -124,7 +159,7 @@ class SnippetDefinition(object):
             'buffer': current.buffer,
             'line': current.window.cursor[0]-1,
             'column': current.window.cursor[1]-1,
-            'cursor': SnippetUtilCursor(current.window.cursor),
+            'cursor': _SnippetUtilCursor(current.window.cursor),
         }
 
         locals.update(additional_locals)
@@ -438,6 +473,6 @@ class SnippetDefinition(object):
             last_re=self._last_re, globals=self._globals,
             context=self._context)
         self.instantiate(snippet_instance, initial_text, indent)
-        snippet_instance.replace_initial_text()
-        snippet_instance.update_textobjects()
+        snippet_instance.replace_initial_text(_vim.buf)
+        snippet_instance.update_textobjects(_vim.buf)
         return snippet_instance
diff --git a/pythonx/UltiSnips/snippet_manager.py b/pythonx/UltiSnips/snippet_manager.py
index dbb20d1..316fe9b 100644
--- a/pythonx/UltiSnips/snippet_manager.py
+++ b/pythonx/UltiSnips/snippet_manager.py
@@ -336,7 +336,7 @@ class SnippetManager(object):
 
         self._check_if_still_inside_snippet()
         if self._csnippets:
-            self._csnippets[0].update_textobjects()
+            self._csnippets[0].update_textobjects(_vim.buf)
             self._vstate.remember_buffer(self._csnippets[0])
 
     def _setup_inner_state(self):
@@ -448,7 +448,7 @@ class SnippetManager(object):
         # we need to set 'onemore' there, because of limitations of the vim
         # API regarding cursor movements; without that test
         # 'CanExpandAnonSnippetInJumpActionWhileSelected' will fail
-        with _vim.toggle_opt('ve', 'onemore'):
+        with _vim.option_set_to('ve', 'onemore'):
             jumped = False
 
             # We need to remember current snippets stack here because of
@@ -489,7 +489,7 @@ class SnippetManager(object):
                     self._cs.current_placeholder = \
                         self._visual_content.placeholder
                     self._should_reset_visual = False
-                    self._csnippets[0].update_textobjects()
+                    self._csnippets[0].update_textobjects(_vim.buf)
                     self._vstate.remember_buffer(self._csnippets[0])
 
                     if ntab.number == 0 and self._csnippets:
diff --git a/pythonx/UltiSnips/text_objects/_base.py b/pythonx/UltiSnips/text_objects/_base.py
index df83954..678bd2a 100644
--- a/pythonx/UltiSnips/text_objects/_base.py
+++ b/pythonx/UltiSnips/text_objects/_base.py
@@ -15,25 +15,26 @@ def _calc_end(text, start):
         new_end = Position(start.line + len(text) - 1, len(text[-1]))
     return new_end
 
-
-def _text_to_vim(start, end, text):
+def _replace_text(buf, start, end, text):
     """Copy the given text to the current buffer, overwriting the span 'start'
     to 'end'."""
     lines = text.split('\n')
 
     new_end = _calc_end(lines, start)
 
-    before = _vim.buf[start.line][:start.col]
-    after = _vim.buf[end.line][end.col:]
+    before = buf[start.line][:start.col]
+    after = buf[end.line][end.col:]
 
     new_lines = []
     if len(lines):
         new_lines.append(before + lines[0])
         new_lines.extend(lines[1:])
         new_lines[-1] += after
-    _vim.buf[start.line:end.line + 1] = new_lines
+    buf[start.line:end.line + 1] = new_lines
 
     # Open any folds this might have created
+    # TODO(sirver): This leaks that we are still inside Vim, while this code should
+    # only care that it is modifying 'buf'.
     _vim.buf.cursor = start
     _vim.command('normal! zv')
 
@@ -115,10 +116,10 @@ class TextObject(object):
         """The end position."""
         return self._end
 
-    def overwrite_with_initial_text(self):
-        self.overwrite(self._initial_text)
+    def overwrite_with_initial_text(self, buf):
+        self.overwrite(buf, self._initial_text)
 
-    def overwrite(self, gtext):
+    def overwrite(self, buf, gtext):
         """Overwrite the text of this object in the Vim Buffer and update its
         length information.
 
@@ -131,16 +132,16 @@ class TextObject(object):
         if self.current_text == gtext:
             return
         old_end = self._end
-        self._end = _text_to_vim(
-            self._start, self._end, gtext)
+        self._end = _replace_text(
+            buf, self._start, self._end, gtext)
         if self._parent:
             self._parent._child_has_moved(
                 self._parent._children.index(self), min(old_end, self._end),
                 self._end.delta(old_end)
             )
 
-    def _update(self, done):
-        """Update this object inside the Vim Buffer.
+    def _update(self, done, buf):
+        """Update this object inside 'buf' which is a list of lines.
 
         Return False if you need to be called again for this edit cycle.
         Otherwise return True.
@@ -357,7 +358,7 @@ class EditableTextObject(TextObject):
         if self._parent and requester is not self._parent:
             return self._parent._get_tabstop(self, number)
 
-    def _update(self, done):
+    def _update(self, done, buf):
         if all((child in done) for child in self._children):
             assert self not in done
             done.add(self)
@@ -385,5 +386,5 @@ class NoneditableTextObject(TextObject):
 
     """All passive text objects that the user can't edit by hand."""
 
-    def _update(self, done):
+    def _update(self, done, buf):
         return True
diff --git a/pythonx/UltiSnips/text_objects/_mirror.py b/pythonx/UltiSnips/text_objects/_mirror.py
index 7f8c961..0e62acd 100644
--- a/pythonx/UltiSnips/text_objects/_mirror.py
+++ b/pythonx/UltiSnips/text_objects/_mirror.py
@@ -14,16 +14,16 @@ class Mirror(NoneditableTextObject):
         NoneditableTextObject.__init__(self, parent, token)
         self._ts = tabstop
 
-    def _update(self, done):
+    def _update(self, done, buf):
         if self._ts.is_killed:
-            self.overwrite('')
+            self.overwrite(buf, '')
             self._parent._del_child(self)   # pylint:disable=protected-access
             return True
 
         if self._ts not in done:
             return False
 
-        self.overwrite(self._get_text())
+        self.overwrite(buf, self._get_text())
         return True
 
     def _get_text(self):
diff --git a/pythonx/UltiSnips/text_objects/_python_code.py b/pythonx/UltiSnips/text_objects/_python_code.py
index 5404dca..00bec6f 100644
--- a/pythonx/UltiSnips/text_objects/_python_code.py
+++ b/pythonx/UltiSnips/text_objects/_python_code.py
@@ -35,7 +35,8 @@ class _Tabs(object):
             int(no))  # pylint:disable=protected-access
         if ts is None:
             return
-        ts.overwrite(value)
+        # TODO(sirver): The buffer should be passed into the object on construction.
+        ts.overwrite(_vim.buf, value)
 
 _VisualContent = namedtuple('_VisualContent', ['mode', 'text'])
 
@@ -52,42 +53,6 @@ class SnippetUtilForAction(dict):
         self.cursor.preserve()
 
 
-class SnippetUtilCursor(object):
-    def __init__(self, cursor):
-        self._cursor = [cursor[0] - 1, cursor[1]]
-        self._set = False
-
-    def preserve(self):
-        self._set = True
-        self._cursor = [
-            _vim.buf.cursor[0],
-            _vim.buf.cursor[1],
-        ]
-
-    def is_set(self):
-        return self._set
-
-    def set(self, line, column):
-        self.__setitem__(0, line)
-        self.__setitem__(1, column)
-
-    def to_vim_cursor(self):
-        return (self._cursor[0] + 1, self._cursor[1])
-
-    def __getitem__(self, index):
-        return self._cursor[index]
-
-    def __setitem__(self, index, value):
-        self._set = True
-        self._cursor[index] = value
-
-    def __len__(self):
-        return 2
-
-    def __str__(self):
-        return str((self._cursor[0], self._cursor[1]))
-
-
 class SnippetUtil(object):
 
     """Provides easy access to indentation, etc.
@@ -290,7 +255,7 @@ class PythonCode(NoneditableTextObject):
         ))
         NoneditableTextObject.__init__(self, parent, token)
 
-    def _update(self, done):
+    def _update(self, done, buf):
         path = _vim.eval('expand("%")') or ''
         ct = self.current_text
         self._locals.update({
@@ -316,6 +281,6 @@ class PythonCode(NoneditableTextObject):
         )
 
         if ct != rv:
-            self.overwrite(rv)
+            self.overwrite(buf, rv)
             return False
         return True
diff --git a/pythonx/UltiSnips/text_objects/_shell_code.py b/pythonx/UltiSnips/text_objects/_shell_code.py
index a7ad964..4fd4601 100644
--- a/pythonx/UltiSnips/text_objects/_shell_code.py
+++ b/pythonx/UltiSnips/text_objects/_shell_code.py
@@ -65,12 +65,12 @@ class ShellCode(NoneditableTextObject):
         self._code = token.code.replace('\\`', '`')
         self._tmpdir = _get_tmp()
 
-    def _update(self, done):
+    def _update(self, done, buf):
         if not self._tmpdir:
             output = \
                 'Unable to find executable tmp directory, check noexec on /tmp'
         else:
             output = _run_shell_command(self._code, self._tmpdir)
-        self.overwrite(output)
+        self.overwrite(buf, output)
         self._parent._del_child(self)  # pylint:disable=protected-access
         return True
diff --git a/pythonx/UltiSnips/text_objects/_snippet_instance.py b/pythonx/UltiSnips/text_objects/_snippet_instance.py
index d63f8ae..592beec 100644
--- a/pythonx/UltiSnips/text_objects/_snippet_instance.py
+++ b/pythonx/UltiSnips/text_objects/_snippet_instance.py
@@ -38,11 +38,11 @@ class SnippetInstance(EditableTextObject):
 
         EditableTextObject.__init__(self, parent, start, end, initial_text)
 
-    def replace_initial_text(self):
+    def replace_initial_text(self, buf):
         """Puts the initial text of all text elements into Vim."""
         def _place_initial_text(obj):
             """recurses on the children to do the work."""
-            obj.overwrite_with_initial_text()
+            obj.overwrite_with_initial_text(buf)
             if isinstance(obj, EditableTextObject):
                 for child in obj._children:
                     _place_initial_text(child)
@@ -54,7 +54,7 @@ class SnippetInstance(EditableTextObject):
         for cmd in cmds:
             self._do_edit(cmd, ctab)
 
-    def update_textobjects(self):
+    def update_textobjects(self, buf):
         """Update the text objects that should change automagically after the
         users edits have been replayed.
 
@@ -77,7 +77,7 @@ class SnippetInstance(EditableTextObject):
         while (done != not_done) and counter:
             # Order matters for python locals!
             for obj in sorted(not_done - done):
-                if obj._update(done):
+                if obj._update(done, buf):
                     done.add(obj)
             counter -= 1
         if not counter:
diff --git a/pythonx/UltiSnips/text_objects/_viml_code.py b/pythonx/UltiSnips/text_objects/_viml_code.py
index 86329bf..3e21474 100644
--- a/pythonx/UltiSnips/text_objects/_viml_code.py
+++ b/pythonx/UltiSnips/text_objects/_viml_code.py
@@ -16,6 +16,6 @@ class VimLCode(NoneditableTextObject):
 
         NoneditableTextObject.__init__(self, parent, token)
 
-    def _update(self, done):
-        self.overwrite(_vim.eval(self._code))
+    def _update(self, done, buf):
+        self.overwrite(buf, _vim.eval(self._code))
         return True
diff --git a/pythonx/UltiSnips/text_objects/_visual.py b/pythonx/UltiSnips/text_objects/_visual.py
index 0be64b3..24735c3 100644
--- a/pythonx/UltiSnips/text_objects/_visual.py
+++ b/pythonx/UltiSnips/text_objects/_visual.py
@@ -11,7 +11,6 @@ If there was no text visually selected, this will be the empty string.
 import re
 import textwrap
 
-from UltiSnips import _vim
 from UltiSnips.indent_util import IndentUtil
 from UltiSnips.text_objects._transformation import TextObjectTransformation
 from UltiSnips.text_objects._base import NoneditableTextObject
@@ -40,11 +39,11 @@ class Visual(NoneditableTextObject, TextObjectTransformation):
         NoneditableTextObject.__init__(self, parent, token)
         TextObjectTransformation.__init__(self, token)
 
-    def _update(self, done):
+    def _update(self, done, buf):
         if self._mode == 'v':  # Normal selection.
             text = self._text
         else:  # Block selection or line selection.
-            text_before = _vim.buf[self.start.line][:self.start.col]
+            text_before = buf[self.start.line][:self.start.col]
             indent = _REPLACE_NON_WS.sub(' ', text_before)
             iu = IndentUtil()
             indent = iu.indent_to_spaces(indent)
@@ -58,7 +57,7 @@ class Visual(NoneditableTextObject, TextObjectTransformation):
             text = text[:-1]  # Strip final '\n'
 
         text = self._transform(text)
-        self.overwrite(text)
+        self.overwrite(buf, text)
         self._parent._del_child(self)  # pylint:disable=protected-access
 
         return True
diff --git a/test/test_Mirror.py b/test/test_Mirror.py
index a6076bf..9a94b6a 100644
--- a/test/test_Mirror.py
+++ b/test/test_Mirror.py
@@ -1,9 +1,6 @@
 from test.vim_test_case import VimTestCase as _VimTest
 from test.constant import *
 
-# Mirrors  {{{#
-
-
 class TextTabStopTextAfterTab_ExpectCorrectResult(_VimTest):
     snippets = ('test', '$1 Hinten\n$1')
     keys = 'test' + EX + 'hallo'
@@ -268,5 +265,3 @@ class Mirror_TestKillTabstop_Kill(_VimTest):
     snippets = 'test', 'welt${1:welt${2:welt}welt} $2'
     keys = 'hallo test' + EX + 'elt'
     wanted = 'hallo weltelt '
-
-# End: Mirrors  #}}}