new file mode 100644
--- /dev/null
+++ b/src/testdir/test_textprop.vim
@@ -0,0 +1,200 @@
+" Tests for defining text property types and adding text properties to the
+" buffer.
+
+if !has('textprop')
+  finish
+endif
+
+func Test_proptype_global()
+  call prop_type_add('comment', {'highlight': 'Directory', 'priority': 123, 'start_incl': 1, 'end_incl': 1})
+  let proptypes = prop_type_list()
+  call assert_equal(1, len(proptypes))
+  call assert_equal('comment', proptypes[0])
+
+  let proptype = prop_type_get('comment')
+  call assert_equal('Directory', proptype['highlight'])
+  call assert_equal(123, proptype['priority'])
+  call assert_equal(1, proptype['start_incl'])
+  call assert_equal(1, proptype['end_incl'])
+
+  call prop_type_delete('comment')
+  call assert_equal(0, len(prop_type_list()))
+
+  call prop_type_add('one', {})
+  call assert_equal(1, len(prop_type_list()))
+  let proptype = prop_type_get('one')
+  call assert_false(has_key(proptype, 'highlight'))
+  call assert_equal(0, proptype['priority'])
+  call assert_equal(0, proptype['start_incl'])
+  call assert_equal(0, proptype['end_incl'])
+
+  call prop_type_add('two', {})
+  call assert_equal(2, len(prop_type_list()))
+  call prop_type_delete('one')
+  call assert_equal(1, len(prop_type_list()))
+  call prop_type_delete('two')
+  call assert_equal(0, len(prop_type_list()))
+endfunc
+
+func Test_proptype_buf()
+  let bufnr = bufnr('')
+  call prop_type_add('comment', {'bufnr': bufnr, 'highlight': 'Directory', 'priority': 123, 'start_incl': 1, 'end_incl': 1})
+  let proptypes = prop_type_list({'bufnr': bufnr})
+  call assert_equal(1, len(proptypes))
+  call assert_equal('comment', proptypes[0])
+
+  let proptype = prop_type_get('comment', {'bufnr': bufnr})
+  call assert_equal('Directory', proptype['highlight'])
+  call assert_equal(123, proptype['priority'])
+  call assert_equal(1, proptype['start_incl'])
+  call assert_equal(1, proptype['end_incl'])
+
+  call prop_type_delete('comment', {'bufnr': bufnr})
+  call assert_equal(0, len(prop_type_list({'bufnr': bufnr})))
+
+  call prop_type_add('one', {'bufnr': bufnr})
+  let proptype = prop_type_get('one', {'bufnr': bufnr})
+  call assert_false(has_key(proptype, 'highlight'))
+  call assert_equal(0, proptype['priority'])
+  call assert_equal(0, proptype['start_incl'])
+  call assert_equal(0, proptype['end_incl'])
+
+  call prop_type_add('two', {'bufnr': bufnr})
+  call assert_equal(2, len(prop_type_list({'bufnr': bufnr})))
+  call prop_type_delete('one', {'bufnr': bufnr})
+  call assert_equal(1, len(prop_type_list({'bufnr': bufnr})))
+  call prop_type_delete('two', {'bufnr': bufnr})
+  call assert_equal(0, len(prop_type_list({'bufnr': bufnr})))
+endfunc
+
+func AddPropTypes()
+  call prop_type_add('one', {})
+  call prop_type_add('two', {})
+  call prop_type_add('three', {})
+  call prop_type_add('whole', {})
+endfunc
+
+func DeletePropTypes()
+  call prop_type_delete('one')
+  call prop_type_delete('two')
+  call prop_type_delete('three')
+  call prop_type_delete('whole')
+endfunc
+
+func SetupPropsInFirstLine()
+  call setline(1, 'one two three')
+  call prop_add(1, 1, {'length': 3, 'id': 11, 'type': 'one'})
+  call prop_add(1, 5, {'length': 3, 'id': 12, 'type': 'two'})
+  call prop_add(1, 8, {'length': 5, 'id': 13, 'type': 'three'})
+  call prop_add(1, 1, {'length': 13, 'id': 14, 'type': 'whole'})
+endfunc
+
+let s:expected_props = [{'col': 1, 'length': 13, 'id': 14, 'type': 'whole', 'start': 1, 'end': 1},
+      \ {'col': 1, 'length': 3, 'id': 11, 'type': 'one', 'start': 1, 'end': 1},
+      \ {'col': 5, 'length': 3, 'id': 12, 'type': 'two', 'start': 1, 'end': 1},
+      \ {'col': 8, 'length': 5, 'id': 13, 'type': 'three', 'start': 1, 'end': 1},
+      \ ]
+
+func Test_prop_add()
+  new
+  call AddPropTypes()
+  call SetupPropsInFirstLine()
+  call assert_equal(s:expected_props, prop_list(1))
+  call assert_fails("call prop_add(10, 1, {'length': 1, 'id': 14, 'type': 'whole'})", 'E966:')
+  call assert_fails("call prop_add(1, 22, {'length': 1, 'id': 14, 'type': 'whole'})", 'E964:')
+ 
+  " Insert a line above, text props must still be there.
+  call append(0, 'empty')
+  call assert_equal(s:expected_props, prop_list(2))
+  " Delete a line above, text props must still be there.
+  1del
+  call assert_equal(s:expected_props, prop_list(1))
+
+  call DeletePropTypes()
+  bwipe!
+endfunc
+
+func Test_prop_remove()
+  new
+  call AddPropTypes()
+  call SetupPropsInFirstLine()
+  let props = deepcopy(s:expected_props)
+  call assert_equal(props, prop_list(1))
+
+  " remove by id
+  call prop_remove({'id': 12}, 1)
+  unlet props[2]
+  call assert_equal(props, prop_list(1))
+
+  " remove by type
+  call prop_remove({'type': 'one'}, 1)
+  unlet props[1]
+  call assert_equal(props, prop_list(1))
+
+  call DeletePropTypes()
+  bwipe!
+endfunc
+
+func Test_prop_add_remove_buf()
+  new
+  let bufnr = bufnr('')
+  call AddPropTypes()
+  call setline(1, 'one two three')
+  wincmd w
+  call prop_add(1, 1, {'length': 3, 'id': 11, 'type': 'one', 'bufnr': bufnr})
+  call prop_add(1, 5, {'length': 3, 'id': 12, 'type': 'two', 'bufnr': bufnr})
+  call prop_add(1, 11, {'length': 3, 'id': 13, 'type': 'three', 'bufnr': bufnr})
+  
+  let props = [
+	\ {'col': 1, 'length': 3, 'id': 11, 'type': 'one', 'start': 1, 'end': 1},
+	\ {'col': 5, 'length': 3, 'id': 12, 'type': 'two', 'start': 1, 'end': 1},
+	\ {'col': 11, 'length': 3, 'id': 13, 'type': 'three', 'start': 1, 'end': 1},
+	\]
+  call assert_equal(props, prop_list(1, {'bufnr': bufnr}))
+ 
+  " remove by id
+  call prop_remove({'id': 12, 'bufnr': bufnr}, 1)
+  unlet props[1]
+  call assert_equal(props, prop_list(1, {'bufnr': bufnr}))
+
+  " remove by type
+  call prop_remove({'type': 'one', 'bufnr': bufnr}, 1)
+  unlet props[0]
+  call assert_equal(props, prop_list(1, {'bufnr': bufnr}))
+
+  call DeletePropTypes()
+  wincmd w
+  bwipe!
+endfunc
+
+
+func Test_prop_clear()
+  new
+  call AddPropTypes()
+  call SetupPropsInFirstLine()
+  call assert_equal(s:expected_props, prop_list(1))
+
+  call prop_clear(1)
+  call assert_equal([], prop_list(1))
+
+  call DeletePropTypes()
+  bwipe!
+endfunc
+
+func Test_prop_clear_buf()
+  new
+  call AddPropTypes()
+  call SetupPropsInFirstLine()
+  let bufnr = bufnr('')
+  wincmd w
+  call assert_equal(s:expected_props, prop_list(1, {'bufnr': bufnr}))
+
+  call prop_clear(1, 1, {'bufnr': bufnr})
+  call assert_equal([], prop_list(1, {'bufnr': bufnr}))
+
+  wincmd w
+  call DeletePropTypes()
+  bwipe!
+endfunc
+
+" TODO: screenshot test with highlighting