patch 8.0.1447: still too many old style tests

Problem:    Still too many old style tests.
Solution:   Turn a few tests into new style. (Yegappan Lakshmanan,
            closes #2509)
diff --git a/src/testdir/test_shortpathname.vim b/src/testdir/test_shortpathname.vim
new file mode 100644
index 0000000..f151788
--- /dev/null
+++ b/src/testdir/test_shortpathname.vim
@@ -0,0 +1,70 @@
+" Test for shortpathname ':8' extension.
+" Only for use on Win32 systems!
+
+if !has('win32')
+  finish
+endif
+
+func TestIt(file, bits, expected)
+  let res = fnamemodify(a:file, a:bits)
+  if a:expected != ''
+    call assert_equal(substitute(a:expected, '/', '\\', 'g'),
+		\ substitute(res, '/', '\\', 'g'),
+		\ "'" . a:file . "'->(" . a:bits . ")->'" . res . "'")
+  endif
+endfunc
+
+func Test_ColonEight()
+  let save_dir = getcwd()
+
+  " This could change for CygWin to //cygdrive/c
+  let dir1 = 'c:/x.x.y'
+  if filereadable(dir1) || isdirectory(dir1)
+    call assert_report("Fatal: '" . dir1 . "' exists, cannot run test")
+    return
+  endif
+
+  let file1 = dir1 . '/zz.y.txt'
+  let nofile1 = dir1 . '/z.y.txt'
+  let dir2 = dir1 . '/VimIsTheGreatestSinceSlicedBread'
+  let file2 = dir2 . '/z.txt'
+  let nofile2 = dir2 . '/zz.txt'
+
+  call mkdir(dir1)
+  let resdir1 = substitute(fnamemodify(dir1, ':p:8'), '/$', '', '')
+  call assert_match('\V\^c:/XX\x\x\x\x~1.Y\$', resdir1)
+
+  let resfile1 = resdir1 . '/ZZY~1.TXT'
+  let resnofile1 = resdir1 . '/z.y.txt'
+  let resdir2 = resdir1 . '/VIMIST~1'
+  let resfile2 = resdir2 . '/z.txt'
+  let resnofile2 = resdir2 . '/zz.txt'
+
+  call mkdir(dir2)
+  call writefile([], file1)
+  call writefile([], file2)
+
+  call TestIt(file1, ':p:8', resfile1)
+  call TestIt(nofile1, ':p:8', resnofile1)
+  call TestIt(file2, ':p:8', resfile2)
+  call TestIt(nofile2, ':p:8', resnofile2)
+  call TestIt(nofile2, ':p:8:h', fnamemodify(resnofile2, ':h'))
+  exe 'cd ' . dir1
+  call TestIt(file1, ':.:8', strpart(resfile1, strlen(resdir1)+1))
+  call TestIt(nofile1, ':.:8', strpart(resnofile1, strlen(resdir1)+1))
+  call TestIt(file2, ':.:8', strpart(resfile2, strlen(resdir1)+1))
+  call TestIt(nofile2, ':.:8', strpart(resnofile2, strlen(resdir1)+1))
+  let $HOME=dir1
+  call TestIt(file1, ':~:8', '~' . strpart(resfile1, strlen(resdir1)))
+  call TestIt(nofile1, ':~:8', '~' . strpart(resnofile1, strlen(resdir1)))
+  call TestIt(file2, ':~:8', '~' . strpart(resfile2, strlen(resdir1)))
+  call TestIt(nofile2, ':~:8', '~' . strpart(resnofile2, strlen(resdir1)))
+
+  cd c:/
+  call delete(file2)
+  call delete(file1)
+  call delete(dir2, 'd')
+  call delete(dir1, 'd')
+
+  exe "cd " . save_dir
+endfunc