diff --git a/src/testdir/test_vartabs.vim b/src/testdir/test_vartabs.vim
new file mode 100644
index 0000000..85914f6
--- /dev/null
+++ b/src/testdir/test_vartabs.vim
@@ -0,0 +1,257 @@
+" Test for variable tabstops
+
+if !has("vartabs")
+  finish
+endif
+
+func! Test_vartabs()
+  new
+  %d
+
+  " Test normal operation of tabstops ...
+  set ts=4
+  call setline(1, join(split('aaaaa', '\zs'), "\t"))
+  retab 8
+  let expect = "a   a\<tab>a   a\<tab>a"
+  call assert_equal(expect, getline(1))
+
+  " ... and softtabstops
+  set ts=8 sts=6
+  exe "norm! Sb\<tab>b\<tab>b\<tab>b\<tab>b"
+  let expect = "b     b\<tab>    b\<tab>  b\<tab>b"
+  call assert_equal(expect, getline(1))
+
+  " Test variable tabstops.
+  set sts=0 vts=4,8,4,8
+  exe "norm! Sc\<tab>c\<tab>c\<tab>c\<tab>c\<tab>c"
+  retab 8
+  let expect = "c   c\<tab>    c\<tab>c\<tab>c\<tab>c"
+  call assert_equal(expect, getline(1))
+
+  set et vts=4,8,4,8
+  exe "norm! Sd\<tab>d\<tab>d\<tab>d\<tab>d\<tab>d"
+  let expect = "d   d       d   d       d       d"
+  call assert_equal(expect, getline(1))
+
+  " Changing ts should have no effect if vts is in use.
+  call cursor(1, 1)
+  set ts=6
+  exe "norm! Se\<tab>e\<tab>e\<tab>e\<tab>e\<tab>e"
+  let expect = "e   e       e   e       e       e"
+  call assert_equal(expect, getline(1))
+
+  " Clearing vts should revert to using ts.
+  set vts=
+  exe "norm! Sf\<tab>f\<tab>f\<tab>f\<tab>f\<tab>f"
+  let expect = "f     f     f     f     f     f"
+  call assert_equal(expect, getline(1))
+
+  " Test variable softtabstops.
+  set noet ts=8 vsts=12,2,6
+  exe "norm! Sg\<tab>g\<tab>g\<tab>g\<tab>g\<tab>g"
+  let expect = "g\<tab>    g g\<tab>    g\<tab>  g\<tab>g"
+  call assert_equal(expect, getline(1))
+
+  " Variable tabstops and softtabstops combined.
+  set vsts=6,12,8 vts=4,6,8
+  exe "norm! Sh\<tab>h\<tab>h\<tab>h\<tab>h"
+  let expect = "h\<tab>  h\<tab>\<tab>h\<tab>h\<tab>h"
+  call assert_equal(expect, getline(1))
+
+  " Retab with a single value, not using vts.
+  set ts=8 sts=0 vts= vsts=
+  exe "norm! Si\<tab>i\<tab>i\<tab>i\<tab>i"
+  retab 4
+  let expect = "i\<tab>\<tab>i\<tab>\<tab>i\<tab>\<tab>i\<tab>\<tab>i"
+  call assert_equal(expect, getline(1))
+
+  " Retab with a single value, using vts.
+  set ts=8 sts=0 vts=6 vsts=
+  exe "norm! Sj\<tab>j\<tab>j\<tab>j\<tab>j"
+  retab 4
+  let expect = "j\<tab>  j\<tab>\<tab>j\<tab>  j\<tab>\<tab>j"
+  call assert_equal(expect, getline(1))
+
+  " Retab with multiple values, not using vts.
+  set ts=6 sts=0 vts= vsts=
+  exe "norm! Sk\<tab>k\<tab>k\<tab>k\<tab>k\<tab>k"
+  retab 4,8
+  let expect = "k\<tab>  k\<tab>k     k\<tab>    k\<tab>  k"
+  call assert_equal(expect, getline(1))
+
+  " Retab with multiple values, using vts.
+  set ts=8 sts=0 vts=6 vsts=
+  exe "norm! Sl\<tab>l\<tab>l\<tab>l\<tab>l\<tab>l"
+  retab 4,8
+  let expect = "l\<tab>  l\<tab>l     l\<tab>    l\<tab>  l"
+  call assert_equal(expect, getline(1))
+
+  " Check that global and local values are set.
+  set ts=4 vts=6 sts=8 vsts=10
+  call assert_equal(&ts, 4)
+  call assert_equal(&vts, '6')
+  call assert_equal(&sts, 8)
+  call assert_equal(&vsts, '10')
+  new
+  call assert_equal(&ts, 4)
+  call assert_equal(&vts, '6')
+  call assert_equal(&sts, 8)
+  call assert_equal(&vsts, '10')
+  bwipeout!
+
+  " Check that local values only are set.
+  setlocal ts=5 vts=7 sts=9 vsts=11
+  call assert_equal(&ts, 5)
+  call assert_equal(&vts, '7')
+  call assert_equal(&sts, 9)
+  call assert_equal(&vsts, '11')
+  new
+  call assert_equal(&ts, 4)
+  call assert_equal(&vts, '6')
+  call assert_equal(&sts, 8)
+  call assert_equal(&vsts, '10')
+  bwipeout!
+
+  " Check that global values only are set.
+  setglobal ts=6 vts=8 sts=10 vsts=12
+  call assert_equal(&ts, 5)
+  call assert_equal(&vts, '7')
+  call assert_equal(&sts, 9)
+  call assert_equal(&vsts, '11')
+  new
+  call assert_equal(&ts, 6)
+  call assert_equal(&vts, '8')
+  call assert_equal(&sts, 10)
+  call assert_equal(&vsts, '12')
+  bwipeout!
+
+  set ts& vts& sts& vsts& et&
+  bwipeout!
+endfunc
+
+func! Test_vartabs_breakindent()
+  if !exists("+breakindent")
+    return
+  endif
+  new
+  %d
+
+  " Test normal operation of tabstops ...
+  set ts=4
+  call setline(1, join(split('aaaaa', '\zs'), "\t"))
+  retab 8
+  let expect = "a   a\<tab>a   a\<tab>a"
+  call assert_equal(expect, getline(1))
+
+  " ... and softtabstops
+  set ts=8 sts=6
+  exe "norm! Sb\<tab>b\<tab>b\<tab>b\<tab>b"
+  let expect = "b     b\<tab>    b\<tab>  b\<tab>b"
+  call assert_equal(expect, getline(1))
+
+  " Test variable tabstops.
+  set sts=0 vts=4,8,4,8
+  exe "norm! Sc\<tab>c\<tab>c\<tab>c\<tab>c\<tab>c"
+  retab 8
+  let expect = "c   c\<tab>    c\<tab>c\<tab>c\<tab>c"
+  call assert_equal(expect, getline(1))
+
+  set et vts=4,8,4,8
+  exe "norm! Sd\<tab>d\<tab>d\<tab>d\<tab>d\<tab>d"
+  let expect = "d   d       d   d       d       d"
+  call assert_equal(expect, getline(1))
+
+  " Changing ts should have no effect if vts is in use.
+  call cursor(1, 1)
+  set ts=6
+  exe "norm! Se\<tab>e\<tab>e\<tab>e\<tab>e\<tab>e"
+  let expect = "e   e       e   e       e       e"
+  call assert_equal(expect, getline(1))
+
+  " Clearing vts should revert to using ts.
+  set vts=
+  exe "norm! Sf\<tab>f\<tab>f\<tab>f\<tab>f\<tab>f"
+  let expect = "f     f     f     f     f     f"
+  call assert_equal(expect, getline(1))
+
+  " Test variable softtabstops.
+  set noet ts=8 vsts=12,2,6
+  exe "norm! Sg\<tab>g\<tab>g\<tab>g\<tab>g\<tab>g"
+  let expect = "g\<tab>    g g\<tab>    g\<tab>  g\<tab>g"
+  call assert_equal(expect, getline(1))
+
+  " Variable tabstops and softtabstops combined.
+  set vsts=6,12,8 vts=4,6,8
+  exe "norm! Sh\<tab>h\<tab>h\<tab>h\<tab>h"
+  let expect = "h\<tab>  h\<tab>\<tab>h\<tab>h\<tab>h"
+  call assert_equal(expect, getline(1))
+
+  " Retab with a single value, not using vts.
+  set ts=8 sts=0 vts= vsts=
+  exe "norm! Si\<tab>i\<tab>i\<tab>i\<tab>i"
+  retab 4
+  let expect = "i\<tab>\<tab>i\<tab>\<tab>i\<tab>\<tab>i\<tab>\<tab>i"
+  call assert_equal(expect, getline(1))
+
+  " Retab with a single value, using vts.
+  set ts=8 sts=0 vts=6 vsts=
+  exe "norm! Sj\<tab>j\<tab>j\<tab>j\<tab>j"
+  retab 4
+  let expect = "j\<tab>  j\<tab>\<tab>j\<tab>  j\<tab>\<tab>j"
+  call assert_equal(expect, getline(1))
+
+  " Retab with multiple values, not using vts.
+  set ts=6 sts=0 vts= vsts=
+  exe "norm! Sk\<tab>k\<tab>k\<tab>k\<tab>k\<tab>k"
+  retab 4,8
+  let expect = "k\<tab>  k\<tab>k     k\<tab>    k\<tab>  k"
+  call assert_equal(expect, getline(1))
+
+  " Retab with multiple values, using vts.
+  set ts=8 sts=0 vts=6 vsts=
+  exe "norm! Sl\<tab>l\<tab>l\<tab>l\<tab>l\<tab>l"
+  retab 4,8
+  let expect = "l\<tab>  l\<tab>l     l\<tab>    l\<tab>  l"
+  call assert_equal(expect, getline(1))
+
+  " Check that global and local values are set.
+  set ts=4 vts=6 sts=8 vsts=10
+  call assert_equal(&ts, 4)
+  call assert_equal(&vts, '6')
+  call assert_equal(&sts, 8)
+  call assert_equal(&vsts, '10')
+  new
+  call assert_equal(&ts, 4)
+  call assert_equal(&vts, '6')
+  call assert_equal(&sts, 8)
+  call assert_equal(&vsts, '10')
+  bwipeout!
+
+  " Check that local values only are set.
+  setlocal ts=5 vts=7 sts=9 vsts=11
+  call assert_equal(&ts, 5)
+  call assert_equal(&vts, '7')
+  call assert_equal(&sts, 9)
+  call assert_equal(&vsts, '11')
+  new
+  call assert_equal(&ts, 4)
+  call assert_equal(&vts, '6')
+  call assert_equal(&sts, 8)
+  call assert_equal(&vsts, '10')
+  bwipeout!
+
+  " Check that global values only are set.
+  setglobal ts=6 vts=8 sts=10 vsts=12
+  call assert_equal(&ts, 5)
+  call assert_equal(&vts, '7')
+  call assert_equal(&sts, 9)
+  call assert_equal(&vsts, '11')
+  new
+  call assert_equal(&ts, 6)
+  call assert_equal(&vts, '8')
+  call assert_equal(&sts, 10)
+  call assert_equal(&vsts, '12')
+  bwipeout!
+
+  bwipeout!
+endfunc