diff --git a/src/testdir/test_ruby.vim b/src/testdir/test_ruby.vim
index 36442fc..8d7943e 100644
--- a/src/testdir/test_ruby.vim
+++ b/src/testdir/test_ruby.vim
@@ -4,6 +4,13 @@
   finish
 end
 
+" Helper function as there is no builtin rubyeval() function similar
+" to perleval, luaevel() or pyeval().
+func RubyEval(ruby_expr)
+  let s = split(execute('ruby print ' . a:ruby_expr), "\n")
+  return (len(s) == 0) ? '' : s[-1]
+endfunc
+
 func Test_ruby_change_buffer()
   call setline(line('$'), ['1 line 1'])
   ruby Vim.command("normal /^1\n")
@@ -11,36 +18,6 @@
   call assert_equal('1 changed line 1', getline('$'))
 endfunc
 
-func Test_ruby_evaluate_list()
-  call setline(line('$'), ['2 line 2'])
-  ruby Vim.command("normal /^2\n")
-  let l = ["abc", "def"]
-  ruby << EOF
-  curline = $curbuf.line_number
-  l = Vim.evaluate("l");
-  $curbuf.append(curline, l.join("\n"))
-EOF
-  normal j
-  .rubydo $_ = $_.gsub(/\n/, '/')
-  call assert_equal('abc/def', getline('$'))
-endfunc
-
-func Test_ruby_evaluate_dict()
-  let d = {'a': 'foo', 'b': 123}
-  redir => l:out
-  ruby d = Vim.evaluate("d"); print d
-  redir END
-  call assert_equal(['{"a"=>"foo", "b"=>123}'], split(l:out, "\n"))
-endfunc
-
-func Test_ruby_evaluate_special_var()
-  let l = [v:true, v:false, v:null, v:none]
-  redir => l:out
-  ruby d = Vim.evaluate("l"); print d
-  redir END
-  call assert_equal(['[true, false, nil, nil]'], split(l:out, "\n"))
-endfunc
-
 func Test_rubydo()
   " Check deleting lines does not trigger ml_get error.
   new
@@ -54,8 +31,7 @@
   call setline(1, ['one', 'two', 'three'])
   rubydo Vim.command("new")
   call assert_equal(wincount + 1, winnr('$'))
-  bwipe!
-  bwipe!
+  %bwipe!
 endfunc
 
 func Test_rubyfile()
@@ -73,8 +49,318 @@
   normal gg
   rubydo $curwin.cursor = [1, 5]
   call assert_equal([1, 6], [line('.'), col('.')])
+  call assert_equal('[1, 5]', RubyEval('$curwin.cursor'))
 
   " Check that movement after setting cursor position keeps current column.
   normal j
   call assert_equal([2, 6], [line('.'), col('.')])
+  call assert_equal('[2, 5]', RubyEval('$curwin.cursor'))
+
+  call assert_fails('ruby $curwin.cursor = [1]',
+        \           'ArgumentError: array length must be 2')
+  bwipe!
+endfunc
+
+" Test buffer.count and buffer.length (number of lines in buffer)
+func Test_buffer_count()
+  new
+  call setline(1, ['one', 'two', 'three'])
+  call assert_equal('3', RubyEval('$curbuf.count'))
+  call assert_equal('3', RubyEval('$curbuf.length'))
+  bwipe!
+endfunc
+
+" Test buffer.name (buffer name)
+func Test_buffer_name()
+  new Xfoo
+  call assert_equal(expand('%:p'), RubyEval('$curbuf.name'))
+  bwipe
+  call assert_equal('', RubyEval('$curbuf.name'))
+endfunc
+
+" Test buffer.number (number of the buffer).
+func Test_buffer_number()
+  new
+  call assert_equal(string(bufnr('%')), RubyEval('$curbuf.number'))
+  new
+  call assert_equal(string(bufnr('%')), RubyEval('$curbuf.number'))
+
+  %bwipe
+endfunc
+
+" Test buffer.delete({n}) (delete line {n})
+func Test_buffer_delete()
+  new
+  call setline(1, ['one', 'two', 'three'])
+  ruby $curbuf.delete(2)
+  call assert_equal(['one', 'three'], getline(1, '$'))
+
+  call assert_fails('ruby $curbuf.delete(0)', 'IndexError: line number 0 out of range')
+  call assert_fails('ruby $curbuf.delete(3)', 'IndexError: line number 3 out of range')
+
+  bwipe!
+endfunc
+
+" Test buffer.append({str}, str) (append line {str} after line {n})
+func Test_buffer_append()
+  new
+  ruby $curbuf.append(0, 'one')
+  ruby $curbuf.append(1, 'three')
+  ruby $curbuf.append(1, 'two')
+  ruby $curbuf.append(4, 'four')
+
+  call assert_equal(['one', 'two', 'three', '', 'four'], getline(1, '$'))
+
+  call assert_fails('ruby $curbuf.append(-1, "x")',
+        \           'IndexError: line number -1 out of range')
+  call assert_fails('ruby $curbuf.append(6, "x")',
+        \           'IndexError: line number 6 out of range')
+
+  bwipe!
+endfunc
+
+" Test buffer.line (get or set the current line)
+func Test_buffer_line()
+  new
+  call setline(1, ['one', 'two', 'three'])
+  2
+  call assert_equal('two', RubyEval('$curbuf.line'))
+
+  ruby $curbuf.line = 'TWO'
+  call assert_equal(['one', 'TWO', 'three'], getline(1, '$'))
+
+  bwipe!
+endfunc
+
+" Test buffer.line_number (get current line number)
+func Test_buffer_line_number()
+  new
+  call setline(1, ['one', 'two', 'three'])
+  2
+  call assert_equal('2', RubyEval('$curbuf.line_number'))
+
+  bwipe!
+endfunc
+
+func Test_buffer_get()
+  new
+  call setline(1, ['one', 'two'])
+  call assert_equal('one', RubyEval('$curbuf[1]'))
+  call assert_equal('two', RubyEval('$curbuf[2]'))
+
+  call assert_fails('ruby $curbuf[0]',
+        \           'IndexError: line number 0 out of range')
+  call assert_fails('ruby $curbuf[3]',
+        \           'IndexError: line number 3 out of range')
+
+  bwipe!
+endfunc
+
+func Test_buffer_set()
+  new
+  call setline(1, ['one', 'two'])
+  ruby $curbuf[2] = 'TWO'
+  ruby $curbuf[1] = 'ONE'
+
+  call assert_fails('ruby $curbuf[0] = "ZERO"',
+        \           'IndexError: line number 0 out of range')
+  call assert_fails('ruby $curbuf[3] = "THREE"',
+        \           'IndexError: line number 3 out of range')
+  bwipe!
+endfunc
+
+" Test window.width (get or set window height).
+func Test_window_height()
+  new
+
+  " Test setting window height
+  ruby $curwin.height = 2
+  call assert_equal(2, winheight(0))
+
+  " Test getting window height
+  call assert_equal('2', RubyEval('$curwin.height'))
+
+  bwipe
+endfunc
+
+" Test window.width (get or set window width).
+func Test_window_width()
+  vnew
+
+  " Test setting window width
+  ruby $curwin.width = 2
+  call assert_equal(2, winwidth(0))
+
+  " Test getting window width
+  call assert_equal('2', RubyEval('$curwin.width'))
+
+  bwipe
+endfunc
+
+" Test window.buffer (get buffer object of a window object).
+func Test_window_buffer()
+  new Xfoo1
+  new Xfoo2
+  ruby $b2 = $curwin.buffer
+  ruby $w2 = $curwin
+  wincmd j
+  ruby $b1 = $curwin.buffer
+  ruby $w1 = $curwin
+
+  call assert_equal(RubyEval('$b1'), RubyEval('$w1.buffer'))
+  call assert_equal(RubyEval('$b2'), RubyEval('$w2.buffer'))
+  call assert_equal(string(bufnr('Xfoo1')), RubyEval('$w1.buffer.number'))
+  call assert_equal(string(bufnr('Xfoo2')), RubyEval('$w2.buffer.number'))
+
+  ruby $b1, $w1, $b2, $w2 = nil
+  %bwipe
+endfunc
+
+" Test Vim::Window.current (get current window object)
+func Test_Vim_window_current()
+  let cw = RubyEval('$curwin')
+  call assert_equal(cw, RubyEval('Vim::Window.current'))
+  call assert_match('^#<Vim::Window:0x\x\+>$', cw)
+endfunc
+
+" Test Vim::Window.count (number of windows)
+func Test_Vim_window_count()
+  new Xfoo1
+  new Xfoo2
+  split
+  call assert_equal('4', RubyEval('Vim::Window.count'))
+  %bwipe
+  call assert_equal('1', RubyEval('Vim::Window.count'))
+endfunc
+
+" Test Vim::Window[n] (get window object of window n)
+func Test_Vim_window_get()
+  new Xfoo1
+  new Xfoo2
+  call assert_match('Xfoo2$', RubyEval('Vim::Window[0].buffer.name'))
+  wincmd j
+  call assert_match('Xfoo1$', RubyEval('Vim::Window[1].buffer.name'))
+  wincmd j
+  call assert_equal('',       RubyEval('Vim::Window[2].buffer.name'))
+  %bwipe
+endfunc
+
+" Test Vim::Buffer.current (return the buffer object of current buffer)
+func Test_Vim_buffer_current()
+  let cb = RubyEval('$curbuf')
+  call assert_equal(cb, RubyEval('Vim::Buffer.current'))
+  call assert_match('^#<Vim::Buffer:0x\x\+>$', cb)
+endfunc
+
+" Test Vim::Buffer:.count (return the number of buffers)
+func Test_Vim_buffer_count()
+  new Xfoo1
+  new Xfoo2
+  call assert_equal('3', RubyEval('Vim::Buffer.count'))
+  %bwipe
+  call assert_equal('1', RubyEval('Vim::Buffer.count'))
+endfunc
+
+" Test Vim::buffer[n] (return the buffer object of buffer number n)
+func Test_Vim_buffer_get()
+  new Xfoo1
+  new Xfoo2
+
+  " Index of Vim::Buffer[n] goes from 0 to the number of buffers.
+  call assert_equal('',       RubyEval('Vim::Buffer[0].name'))
+  call assert_match('Xfoo1$', RubyEval('Vim::Buffer[1].name'))
+  call assert_match('Xfoo2$', RubyEval('Vim::Buffer[2].name'))
+  call assert_fails('ruby print Vim::Buffer[3].name',
+        \           "NoMethodError: undefined method `name' for nil:NilClass")
+  %bwipe
+endfunc
+
+" Test Vim::command({cmd}) (execute a Ex command))
+" Test Vim::command({cmd})
+func Test_Vim_command()
+  new
+  call setline(1, ['one', 'two', 'three', 'four'])
+  ruby Vim::command('2,3d')
+  call assert_equal(['one', 'four'], getline(1, '$'))
+  bwipe!
+endfunc
+
+" Test Vim::set_option (set a vim option)
+func Test_Vim_set_option()
+  call assert_equal(0, &number)
+  ruby Vim::set_option('number')
+  call assert_equal(1, &number)
+  ruby Vim::set_option('nonumber')
+  call assert_equal(0, &number)
+endfunc
+
+func Test_Vim_evaluate()
+  call assert_equal('123',      RubyEval('Vim::evaluate("123")'))
+  " Vim::evaluate("123").class gives Integer or Fixnum depending
+  " on versions of Ruby.
+  call assert_match('^Integer\|Fixnum$', RubyEval('Vim::evaluate("123").class'))
+
+  call assert_equal('1.23',     RubyEval('Vim::evaluate("1.23")'))
+  call assert_equal('Float',    RubyEval('Vim::evaluate("1.23").class'))
+
+  call assert_equal('foo',      RubyEval('Vim::evaluate("\"foo\"")'))
+  call assert_equal('String',   RubyEval('Vim::evaluate("\"foo\"").class'))
+
+  call assert_equal('[1, 2]',   RubyEval('Vim::evaluate("[1, 2]")'))
+  call assert_equal('Array',    RubyEval('Vim::evaluate("[1, 2]").class'))
+
+  call assert_equal('{"1"=>2}', RubyEval('Vim::evaluate("{1:2}")'))
+  call assert_equal('Hash',     RubyEval('Vim::evaluate("{1:2}").class'))
+
+  call assert_equal('',         RubyEval('Vim::evaluate("v:null")'))
+  call assert_equal('NilClass', RubyEval('Vim::evaluate("v:null").class'))
+
+  call assert_equal('',         RubyEval('Vim::evaluate("v:none")'))
+  call assert_equal('NilClass', RubyEval('Vim::evaluate("v:none").class'))
+
+  call assert_equal('true',      RubyEval('Vim::evaluate("v:true")'))
+  call assert_equal('TrueClass', RubyEval('Vim::evaluate("v:true").class'))
+  call assert_equal('false',     RubyEval('Vim::evaluate("v:false")'))
+  call assert_equal('FalseClass',RubyEval('Vim::evaluate("v:false").class'))
+endfunc
+
+func Test_Vim_evaluate_list()
+  call setline(line('$'), ['2 line 2'])
+  ruby Vim.command("normal /^2\n")
+  let l = ["abc", "def"]
+  ruby << EOF
+  curline = $curbuf.line_number
+  l = Vim.evaluate("l");
+  $curbuf.append(curline, l.join("\n"))
+EOF
+  normal j
+  .rubydo $_ = $_.gsub(/\n/, '/')
+  call assert_equal('abc/def', getline('$'))
+endfunc
+
+func Test_Vim_evaluate_dict()
+  let d = {'a': 'foo', 'b': 123}
+  redir => l:out
+  ruby d = Vim.evaluate("d"); print d
+  redir END
+  call assert_equal(['{"a"=>"foo", "b"=>123}'], split(l:out, "\n"))
+endfunc
+
+" Test Vim::message({msg}) (display message {msg})
+func Test_Vim_message()
+  ruby Vim::message('A message')
+  let messages = split(execute('message'), "\n")
+  call assert_equal('A message', messages[-1])
+endfunc
+
+func Test_print()
+  ruby print "Hello World!"
+  let messages = split(execute('message'), "\n")
+  call assert_equal('Hello World!', messages[-1])
+endfunc
+
+func Test_p()
+  ruby p 'Just a test'
+  let messages = split(execute('message'), "\n")
+  call assert_equal('"Just a test"', messages[-1])
 endfunc