Wrap Python functions, fix last diff.

plugin/gundo.vim

@@ -508,6 +508,13 @@ def _goto_window_for_buffer(b):
 def _goto_window_for_buffer_name(bn):
     b = vim.eval('bufnr("%s")' % bn)
     _goto_window_for_buffer(b)
+
+INLINE_HELP = '''\
+" Gundo for %s [%d]
+" j/k  - move between undo states
+" <cr> - revert to that state
+
+'''
 ENDPYTHON
 "}}}
 
@@ -561,6 +568,7 @@ ENDPYTHON
 function! s:GundoRender()
 python << ENDPYTHON
 
+def GundoRender():
     ut = vim.eval('undotree()')
     entries = ut['entries']
 
@@ -582,17 +590,12 @@ result = generate(walk_nodes(dag), asciiedges, current).splitlines()
     result = [' ' + l for l in result]
 
     target = (vim.eval('g:gundo_target_f'), int(vim.eval('g:gundo_target_n')))
-INLINE_HELP = ('''\
-" Gundo for %s [%d]
-" j/k  - move between undo states
-" <cr> - revert to that state
-
-''' % target).splitlines()
+    header = (INLINE_HELP % target).splitlines()
 
     vim.command('GundoOpenBuffer')
     vim.command('setlocal modifiable')
     vim.command('normal ggdG')
-vim.current.buffer[:] = (INLINE_HELP + result)
+    vim.current.buffer[:] = (header + result)
     vim.command('setlocal nomodifiable')
 
     i = 1
@@ -604,8 +607,9 @@ for line in result:
         except ValueError:
             pass
         i += 1
-vim.command('%d' % (i+3))
+    vim.command('%d' % (i+len(header)-1))
 
+GundoRender()
 ENDPYTHON
 endfunction
 "}}}
@@ -615,6 +619,7 @@ function! s:GundoRenderPreview(target)
 python << ENDPYTHON
 import difflib
 
+def GundoRenderPreview():
     _goto_window_for_buffer(vim.eval('g:gundo_target_n'))
 
     root, nodes = make_nodes(entries)
@@ -624,6 +629,9 @@ target_n = int(vim.eval('a:target'))
     node_after = [node for node in nodes if node.n == target_n][0]
     node_before = node_after.parent
 
+    if not node_before.n:
+        before = []
+    else:
         vim.command('silent undo %d' % node_before.n)
         before = vim.current.buffer[:]
     vim.command('silent undo %d' % node_after.n)
@@ -640,6 +648,7 @@ vim.command('setlocal nomodifiable')
 
     _goto_window_for_buffer_name('__Gundo__')
 
+GundoRenderPreview()
 ENDPYTHON
 endfunction
 "}}}