1 files changed, 97 insertions, 0 deletions
diff --git a/src/testdir/test_changedtick.vim b/src/testdir/test_changedtick.vim
new file mode 100644
index 0000000..b7e7cd6
--- /dev/null
+++ b/src/testdir/test_changedtick.vim
@@ -0,0 +1,97 @@
+" Tests for b:changedtick
+
+func Test_changedtick_increments()
+  new
+  " New buffer has an empty line, tick starts at 2.
+  let expected = 2
+  call assert_equal(expected, b:changedtick)
+  call assert_equal(expected, b:['changedtick'])
+  call setline(1, 'hello')
+  let expected += 1
+  call assert_equal(expected, b:changedtick)
+  call assert_equal(expected, b:['changedtick'])
+  undo
+  " Somehow undo counts as two changes.
+  let expected += 2
+  call assert_equal(expected, b:changedtick)
+  call assert_equal(expected, b:['changedtick'])
+  bwipe!
+endfunc
+
+func Test_changedtick_dict_entry()
+  let d = b:
+  call assert_equal(b:changedtick, d['changedtick'])
+endfunc
+
+func Test_changedtick_bdel()
+  new
+  let bnr = bufnr('%')
+  let v = b:changedtick
+  bdel
+  " Delete counts as a change too.
+  call assert_equal(v + 1, getbufvar(bnr, 'changedtick'))
+endfunc
+
+func Test_changedtick_islocked()
+  call assert_equal(0, islocked('b:changedtick'))
+  let d = b:
+  call assert_equal(0, islocked('d.changedtick'))
+endfunc
+
+func Test_changedtick_fixed()
+  call assert_fails('let b:changedtick = 4', 'E46:')
+  call assert_fails('let b:["changedtick"] = 4', 'E46:')
+
+  call assert_fails('lockvar b:changedtick', 'E940:')
+  call assert_fails('lockvar b:["changedtick"]', 'E46:')
+  call assert_fails('unlockvar b:changedtick', 'E940:')
+  call assert_fails('unlockvar b:["changedtick"]', 'E46:')
+  call assert_fails('unlet b:changedtick', 'E795:')
+  call assert_fails('unlet b:["changedtick"]', 'E46:')
+
+  let d = b:
+  call assert_fails('lockvar d["changedtick"]', 'E46:')
+  call assert_fails('unlockvar d["changedtick"]', 'E46:')
+  call assert_fails('unlet d["changedtick"]', 'E46:')
+
+endfunc
+
+func Test_changedtick_not_incremented_with_write()
+  new
+  let fname = "XChangeTick"
+  exe 'w ' .. fname
+
+  " :write when the buffer is not changed does not increment changedtick
+  let expected = b:changedtick
+  w
+  call assert_equal(expected, b:changedtick)
+
+  " :write when the buffer IS changed DOES increment changedtick
+  let expected = b:changedtick + 1
+  setlocal modified
+  w
+  call assert_equal(expected, b:changedtick)
+
+  " Two ticks: change + write
+  let expected = b:changedtick + 2
+  call setline(1, 'hello')
+  w
+  call assert_equal(expected, b:changedtick)
+
+  " Two ticks: start insert + write
+  let expected = b:changedtick + 2
+  normal! o
+  w
+  call assert_equal(expected, b:changedtick)
+
+  " Three ticks: start insert + change + write
+  let expected = b:changedtick + 3
+  normal! ochanged
+  w
+  call assert_equal(expected, b:changedtick)
+
+  bwipe
+  call delete(fname)
+endfunc
+
+" vim: shiftwidth=2 sts=2 expandtab