Fix Vader's tests for older Vim

Vader's own test suite fails when using an older Vim (the one installed on Travis already).

```
$ vim --version
VIM - Vi IMproved 7.4 (2013 Aug 10, compiled Nov 24 2016 16:43:18)
Included patches: 1-52
Extra patches: 8.0.0056
```

Build log: https://travis-ci.org/junegunn/vader.vim/jobs/321548833

```
Vim: Warning: Output is not to a terminal
VIM - Vi IMproved 7.4 (2013 Aug 10, compiled Nov 24 2016 16:43:18)
Included patches: 1-52
Extra patches: 8.0.0056
Modified by pkg-vim-maintainers@lists.alioth.debian.org
Compiled by buildd@
Huge version without GUI. Features included (+) or not (-):
+acl +farsi +mouse_netterm +syntax
+arabic +file_in_path +mouse_sgr +tag_binary
+autocmd +find_in_path -mouse_sysmouse +tag_old_static
-balloon_eval +float +mouse_urxvt -tag_any_white
-browse +folding +mouse_xterm -tcl
++builtin_terms -footer +multi_byte +terminfo
+byte_offset +fork() +multi_lang +termresponse
+cindent +gettext -mzscheme +textobjects
-clientserver -hangul_input +netbeans_intg +title
-clipboard +iconv +path_extra -toolbar
+cmdline_compl +insert_expand -perl +user_commands
+cmdline_hist +jumplist +persistent_undo +vertsplit
+cmdline_info +keymap +postscript +virtualedit
+comments +langmap +printer +visual
+conceal +libcall +profile +visualextra
+cryptv +linebreak +python +viminfo
+cscope +lispindent -python3 +vreplace
+cursorbind +listcmds +quickfix +wildignore
+cursorshape +localmap +reltime +wildmenu
+dialog_con -lua +rightleft +windows
+diff +menu -ruby +writebackup
+digraphs +mksession +scrollbind -X11
-dnd +modify_fname +signs -xfontset
-ebcdic +mouse +smartindent -xim
+emacs_tags -mouseshape -sniff -xsmp
+eval +mouse_dec +startuptime -xterm_clipboard
+ex_extra +mouse_gpm +statusline -xterm_save
+extra_search -mouse_jsbterm -sun_workshop -xpm
system vimrc file: "$VIM/vimrc"
user vimrc file: "$HOME/.vimrc"
2nd user vimrc file: "~/.vim/vimrc"
user exrc file: "$HOME/.exrc"
fall-back for $VIM: "/usr/share/vim"
Compilation: gcc -c -I. -Iproto -DHAVE_CONFIG_H -g -O2 -fstack-protector --param=ssp-buffer-size=4 -Wformat -Werror=format-security -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=1
Linking: gcc -Wl,-Bsymbolic-functions -Wl,-z,relro -Wl,--as-needed -o vim -lm -ltinfo -lnsl -lselinux -lacl -lattr -lgpm -ldl -L/usr/lib/python2.7/config-x86_64-linux-gnu -lpython2.7 -lpthread -ldl -lutil -lm -Xlinker -export-dynamic -Wl,-O1 -Wl,-Bsymbolic-functions

Starting Vader: 1 suite(s), 64 case(s)
Starting Vader: /home/travis/build/junegunn/vader.vim/test/vader.vader
( 1/64) [EXECUTE]
> Hello !
( 2/64) [EXECUTE] Assert and AssertEqual command
( 3/64) [EXECUTE] AssertThrows
( 3/64) [EXECUTE] (X) 'function vader#assert#throws[5]..VaderThrows, line 1' should be equal to 'function vader#assert#throws..VaderThrows, line 1'
( 4/64) [EXECUTE] AssertEqual handles funcrefs
( 5/64) [EXECUTE] FIXME: AssertThrows expects an exception to be thrown
( 5/64) [EXECUTE] (X) Exception expected but not raised: call reverse([1, 2, 3])
( 6/64) [EXECUTE] FIXME: Optional message parameter to Assert command
( 6/64) [EXECUTE] (X) 1 is not equal to 2
( 7/64) [EXECUTE] FIXME: Optional message parameter to AssertEqual
( 7/64) [EXECUTE] (X) 1 != 2
( 8/64) [EXECUTE] FIXME: Optional message parameter to AssertNotEqual
( 8/64) [EXECUTE] (X) 1 == 2
( 9/64) [EXECUTE] Save global option values before changing them
(10/64) [ GIVEN] Block content is injected and highlighted as ruby code
(10/64) [ DO] Do block content is keystrokes in normal mode
(10/64) [ EXPECT] Expect block content should match the result of previous Do block
(11/64) [ GIVEN] Block content is injected and highlighted as ruby code
(11/64) [ DO] FIXME: Nothing
(11/64) [ EXPECT] (X) Previous Given block is repeated, thus this should fail
- Expected:
def b
a = 1
end
- Got:
def a
a = 1
end
(12/64) [ GIVEN] Block content is injected and highlighted as ruby code
(12/64) [ DO] Indent and shift given ruby code
(12/64) [ EXPECT] indented and shifted
(13/64) [ GIVEN] Block content is injected and highlighted as ruby code
(13/64) [ DO] FIXME: Execute a non-existent command should raise an error
(13/64) [ DO] (X) Vim:E492: Not an editor command: non-existent-command
> function 20_vader..vader#run..21_run..vader#window#replay, line 2
(14/64) [ GIVEN] Block content is injected and highlighted as ruby code
(14/64) [EXECUTE] Revert changed option values
(15/64) [ GIVEN]
(15/64) [ DO]
(15/64) [ EXPECT]
(16/64) [ GIVEN]
(16/64) [EXECUTE] FIXME: Execute block does not require an Expect block
(16/64) [EXECUTE] (X) 2 should be equal to 1
(17/64) [ GIVEN]
(17/64) [ DO] Do block *not* followed by an Expect block
(18/64) [ GIVEN]
(18/64) [ DO] Do block followed by an Expect block
(18/64) [ EXPECT]
(19/64) [ GIVEN]
(19/64) [EXECUTE] FIXME: Execute block can also be followed by an Expect block
(19/64) [ EXPECT] (X) Comparison is case-sensitive
- Expected:
some string
MORE string
even more string
- Got:
Some string
more string
even more string
(20/64) [ GIVEN]
(20/64) [ DO] ]]
(20/64) [ EXPECT]
(21/64) [ GIVEN]
(21/64) [ DO] [[
(21/64) [ EXPECT]
(22/64) [ GIVEN]
(22/64) [ DO] ][ / []
(22/64) [ EXPECT]
(23/64) [ GIVEN] fixture
(23/64) [ DO] modification
(23/64) [ EXPECT] result
(24/64) [ GIVEN] fixture
(24/64) [ DO] another modification
(24/64) [ EXPECT] invalid result
(25/64) [ GIVEN] fixture
(25/64) [EXECUTE]
(26/64) [ GIVEN] fixture
> Before block increases counter by 1
(26/64) [EXECUTE]
> It should be 1
> After block increases counter by 2
(27/64) [ GIVEN] fixture
> Before block increases counter by 1
(27/64) [EXECUTE]
> It should be 4
> After block increases counter by 2
(28/64) [ GIVEN] fixture
(28/64) [EXECUTE]
> Goodbye!
(29/64) [ GIVEN] fixture
(29/64) [EXECUTE] Initialize vars
(30/64) [ GIVEN] fixture
(30/64) [EXECUTE] Save vars - comma-separated list of optionally-quoted names
(31/64) [ GIVEN] fixture
(31/64) [EXECUTE] Save/Restore vars by value
(32/64) [ GIVEN] fixture
(32/64) [EXECUTE] Set previously undefined vars
(33/64) [ GIVEN] fixture
(33/64) [EXECUTE] Unlet vars
(34/64) [ GIVEN] fixture
(34/64) [EXECUTE] Restore g:abc and g:def - names can be optionally quoted
(35/64) [ GIVEN] fixture
(35/64) [EXECUTE] Check g:abc and g:def
(36/64) [ GIVEN] fixture
(36/64) [EXECUTE] g:xyz and $ENVVAR should not exist
(37/64) [ GIVEN] fixture
(37/64) [EXECUTE] Restore everything
(38/64) [ GIVEN] fixture
(38/64) [EXECUTE] g:undefined should not exist
(39/64) [ GIVEN] fixture
(39/64) [EXECUTE] Restore everthing again
(40/64) [ GIVEN] fixture
(40/64) [EXECUTE] Cleanup
(41/64) [ GIVEN] Some string
(41/64) [EXECUTE] Ruby code
(41/64) [EXECUTE] (X) Vim(ruby):E319: Sorry, the command is not available in this version: ruby << __VADER__LANG__IF__
> /tmp/vxvCRJa/33, line 1
(41/64) [ EXPECT] (X)
- Expected:
Hello
Hello
vader.vader
- Got:
Hello
(42/64) [ GIVEN] Some string
(42/64) [EXECUTE] Python code
(42/64) [ EXPECT]
(43/64) [ GIVEN] markdown without indentation
(43/64) [EXECUTE]
> Hello !
(44/64) [ GIVEN] markdown without indentation
(44/64) [ DO]
(44/64) [ EXPECT] without indentation
(45/64) [ GIVEN] markdown without indentation
(45/64) [EXECUTE]
(45/64) [ EXPECT]
(46/64) [ GIVEN] C file
(46/64) [EXECUTE] SyntaxAt()
(47/64) [ GIVEN] C file
(47/64) [EXECUTE] SyntaxAt(col)
(48/64) [ GIVEN] C file
(48/64) [EXECUTE] SyntaxAt(lnum, col)
(49/64) [ GIVEN] C file
(49/64) [EXECUTE] SyntaxOf(pattern)
(50/64) [ GIVEN] C file
(50/64) [EXECUTE] SyntaxOf(pattern, count)
(51/64) [ GIVEN] C file
(51/64) [EXECUTE] SyntaxOf does not move cursor
(52/64) [ GIVEN]
(52/64) [ DO] Macro that ends with
(52/64) [ EXPECT]
(53/64) [ GIVEN]
(53/64) [EXECUTE] Assertions
(54/64) [ GIVEN]
(54/64) [EXECUTE] Create temp file
(55/64) [ GIVEN] File path
(55/64) [ DO] Go to file
(55/64) [ EXPECT] Should see the content of the current buffer instead of workbench buffer
(56/64) [ GIVEN] File path
(56/64) [ DO] Vader should switch back to the workbench buffer
(56/64) [ EXPECT] Modified workbench buffer
(57/64) [ GIVEN] File path
(57/64) [EXECUTE] The buffer shouldn't have been modified
(58/64) [EXECUTE] Check filetype
(59/64) [EXECUTE] Check filetype
(60/64) [EXECUTE] Check filetype again
(61/64) [EXECUTE] Check filetype - should be reset
(62/64) [ GIVEN] Vader file with interleaved comments
(62/64) [EXECUTE] Check syntax
(63/64) [ GIVEN] Vader file with interleaved comments
(63/64) [EXECUTE] buftype in new tabpage
(64/64) [ GIVEN] Vader file with interleaved comments
(64/64) [EXECUTE]
> Good-bye !
Success/Total: 54/64 (8 pending)
Success/Total: 54/64 (8 pending, assertions: 66/72)
Elapsed time: 0.719538 sec.
```
It would be nice if tests would pass there (potentially skipping some of them).