Merge pull request #11742 from bfredl/shedbike

shed biking: it's always extmarks, never marks extended

1 files changed, 1477 insertions, 0 deletions

diff --git a/test/functional/api/extmark_spec.lua b/test/functional/api/extmark_spec.lua
new file mode 100644
index 0000000000..5bf3fa554f
--- /dev/null
+++ b/test/functional/api/extmark_spec.lua
@@ -0,0 +1,1477 @@
+local helpers = require('test.functional.helpers')(after_each)
+local Screen = require('test.functional.ui.screen')
+
+local request = helpers.request
+local eq = helpers.eq
+local ok = helpers.ok
+local curbufmeths = helpers.curbufmeths
+local bufmeths = helpers.bufmeths
+local pcall_err = helpers.pcall_err
+local insert = helpers.insert
+local feed = helpers.feed
+local clear = helpers.clear
+local command = helpers.command
+local meths = helpers.meths
+
+local function expect(contents)
+  return eq(contents, helpers.curbuf_contents())
+end
+
+local function check_undo_redo(ns, mark, sr, sc, er, ec) --s = start, e = end
+  local rv = curbufmeths.get_extmark_by_id(ns, mark)
+  eq({er, ec}, rv)
+  feed("u")
+  rv = curbufmeths.get_extmark_by_id(ns, mark)
+  eq({sr, sc}, rv)
+  feed("<c-r>")
+  rv = curbufmeths.get_extmark_by_id(ns, mark)
+  eq({er, ec}, rv)
+end
+
+local function set_extmark(ns_id, id, line, col, opts)
+  if opts == nil then
+    opts = {}
+  end
+  return curbufmeths.set_extmark(ns_id, id, line, col, opts)
+end
+
+local function get_extmarks(ns_id, start, end_, opts)
+  if opts == nil then
+    opts = {}
+  end
+  return curbufmeths.get_extmarks(ns_id, start, end_, opts)
+end
+
+local function batch_set(ns_id, positions)
+  local ids = {}
+  for _, pos in ipairs(positions) do
+    table.insert(ids, set_extmark(ns_id, 0, pos[1], pos[2]))
+  end
+  return ids
+end
+
+local function batch_check(ns_id, ids, positions)
+  local actual, expected = {}, {}
+  for i,id in ipairs(ids) do
+    expected[id] = positions[i]
+  end
+  for _, mark in pairs(get_extmarks(ns_id, 0, -1, {})) do
+    actual[mark[1]] = {mark[2], mark[3]}
+  end
+  eq(expected, actual)
+end
+
+local function batch_check_undo_redo(ns_id, ids, before, after)
+  batch_check(ns_id, ids, after)
+  feed("u")
+  batch_check(ns_id, ids, before)
+  feed("<c-r>")
+  batch_check(ns_id, ids, after)
+end
+
+describe('API/extmarks', function()
+  local screen
+  local marks, positions, init_text, row, col
+  local ns, ns2
+
+  before_each(function()
+    -- Initialize some namespaces and insert 12345 into a buffer
+    marks = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12}
+    positions = {{0, 0,}, {0, 2}, {0, 3}}
+
+    init_text = "12345"
+    row = 0
+    col = 2
+
+    clear()
+
+    insert(init_text)
+    ns = request('nvim_create_namespace', "my-fancy-plugin")
+    ns2 = request('nvim_create_namespace', "my-fancy-plugin2")
+  end)
+
+  it('adds, updates  and deletes marks', function()
+    local rv = set_extmark(ns, marks[1], positions[1][1], positions[1][2])
+    eq(marks[1], rv)
+    rv = curbufmeths.get_extmark_by_id(ns, marks[1])
+    eq({positions[1][1], positions[1][2]}, rv)
+    -- Test adding a second mark on same row works
+    rv = set_extmark(ns, marks[2], positions[2][1], positions[2][2])
+    eq(marks[2], rv)
+
+    -- Test an update, (same pos)
+    rv = set_extmark(ns, marks[1], positions[1][1], positions[1][2])
+    eq(marks[1], rv)
+    rv = curbufmeths.get_extmark_by_id(ns, marks[2])
+    eq({positions[2][1], positions[2][2]}, rv)
+    -- Test an update, (new pos)
+    row = positions[1][1]
+    col = positions[1][2] + 1
+    rv = set_extmark(ns, marks[1], row, col)
+    eq(marks[1], rv)
+    rv = curbufmeths.get_extmark_by_id(ns, marks[1])
+    eq({row, col}, rv)
+
+    -- remove the test marks
+    eq(true, curbufmeths.del_extmark(ns, marks[1]))
+    eq(false, curbufmeths.del_extmark(ns, marks[1]))
+    eq(true, curbufmeths.del_extmark(ns, marks[2]))
+    eq(false, curbufmeths.del_extmark(ns, marks[3]))
+    eq(false, curbufmeths.del_extmark(ns, 1000))
+  end)
+
+  it('can clear a specific namespace range', function()
+    set_extmark(ns, 1, 0, 1)
+    set_extmark(ns2, 1, 0, 1)
+    -- force a new undo buffer
+    feed('o<esc>')
+    curbufmeths.clear_namespace(ns2, 0, -1)
+    eq({{1, 0, 1}}, get_extmarks(ns, {0, 0}, {-1, -1}))
+    eq({}, get_extmarks(ns2, {0, 0}, {-1, -1}))
+    feed('u')
+    eq({{1, 0, 1}}, get_extmarks(ns, {0, 0}, {-1, -1}))
+    eq({}, get_extmarks(ns2, {0, 0}, {-1, -1}))
+    feed('<c-r>')
+    eq({{1, 0, 1}}, get_extmarks(ns, {0, 0}, {-1, -1}))
+    eq({}, get_extmarks(ns2, {0, 0}, {-1, -1}))
+  end)
+
+  it('can clear a namespace range using 0,-1', function()
+    set_extmark(ns, 1, 0, 1)
+    set_extmark(ns2, 1, 0, 1)
+    -- force a new undo buffer
+    feed('o<esc>')
+    curbufmeths.clear_namespace(-1, 0, -1)
+    eq({}, get_extmarks(ns, {0, 0}, {-1, -1}))
+    eq({}, get_extmarks(ns2, {0, 0}, {-1, -1}))
+    feed('u')
+    eq({}, get_extmarks(ns, {0, 0}, {-1, -1}))
+    eq({}, get_extmarks(ns2, {0, 0}, {-1, -1}))
+    feed('<c-r>')
+    eq({}, get_extmarks(ns, {0, 0}, {-1, -1}))
+    eq({}, get_extmarks(ns2, {0, 0}, {-1, -1}))
+  end)
+
+  it('querying for information and ranges', function()
+    --marks = {1, 2, 3}
+    --positions = {{0, 0,}, {0, 2}, {0, 3}}
+    -- add some more marks
+    for i, m in ipairs(marks) do
+      if positions[i] ~= nil then
+        local rv = set_extmark(ns, m, positions[i][1], positions[i][2])
+        eq(m, rv)
+      end
+    end
+
+    -- {0, 0} and {-1, -1} work as extreme values
+    eq({{1, 0, 0}}, get_extmarks(ns, {0, 0}, {0, 0}))
+    eq({}, get_extmarks(ns, {-1, -1}, {-1, -1}))
+    local rv = get_extmarks(ns, {0, 0}, {-1, -1})
+    for i, m in ipairs(marks) do
+      if positions[i] ~= nil then
+        eq({m, positions[i][1], positions[i][2]}, rv[i])
+      end
+    end
+
+    -- 0 and -1 works as short hand extreme values
+    eq({{1, 0, 0}}, get_extmarks(ns, 0, 0))
+    eq({}, get_extmarks(ns, -1, -1))
+    rv = get_extmarks(ns, 0, -1)
+    for i, m in ipairs(marks) do
+      if positions[i] ~= nil then
+        eq({m, positions[i][1], positions[i][2]}, rv[i])
+      end
+    end
+
+    -- next with mark id
+    rv = get_extmarks(ns, marks[1], {-1, -1}, {limit=1})
+    eq({{marks[1], positions[1][1], positions[1][2]}}, rv)
+    rv = get_extmarks(ns, marks[2], {-1, -1}, {limit=1})
+    eq({{marks[2], positions[2][1], positions[2][2]}}, rv)
+    -- next with positional when mark exists at position
+    rv = get_extmarks(ns, positions[1], {-1, -1}, {limit=1})
+    eq({{marks[1], positions[1][1], positions[1][2]}}, rv)
+    -- next with positional index (no mark at position)
+    rv = get_extmarks(ns, {positions[1][1], positions[1][2] +1}, {-1, -1}, {limit=1})
+    eq({{marks[2], positions[2][1], positions[2][2]}}, rv)
+    -- next with Extremity index
+    rv = get_extmarks(ns, {0,0}, {-1, -1}, {limit=1})
+    eq({{marks[1], positions[1][1], positions[1][2]}}, rv)
+
+    -- nextrange with mark id
+    rv = get_extmarks(ns, marks[1], marks[3])
+    eq({marks[1], positions[1][1], positions[1][2]}, rv[1])
+    eq({marks[2], positions[2][1], positions[2][2]}, rv[2])
+    -- nextrange with `limit`
+    rv = get_extmarks(ns, marks[1], marks[3], {limit=2})
+    eq(2, table.getn(rv))
+    -- nextrange with positional when mark exists at position
+    rv = get_extmarks(ns, positions[1], positions[3])
+    eq({marks[1], positions[1][1], positions[1][2]}, rv[1])
+    eq({marks[2], positions[2][1], positions[2][2]}, rv[2])
+    rv = get_extmarks(ns, positions[2], positions[3])
+    eq(2, table.getn(rv))
+    -- nextrange with positional index (no mark at position)
+    local lower = {positions[1][1], positions[2][2] -1}
+    local upper = {positions[2][1], positions[3][2] - 1}
+    rv = get_extmarks(ns, lower, upper)
+    eq({{marks[2], positions[2][1], positions[2][2]}}, rv)
+    lower = {positions[3][1], positions[3][2] + 1}
+    upper = {positions[3][1], positions[3][2] + 2}
+    rv = get_extmarks(ns, lower, upper)
+    eq({}, rv)
+    -- nextrange with extremity index
+    lower = {positions[2][1], positions[2][2]+1}
+    upper = {-1, -1}
+    rv = get_extmarks(ns, lower, upper)
+    eq({{marks[3], positions[3][1], positions[3][2]}}, rv)
+
+    -- prev with mark id
+    rv = get_extmarks(ns, marks[3], {0, 0}, {limit=1})
+    eq({{marks[3], positions[3][1], positions[3][2]}}, rv)
+    rv = get_extmarks(ns, marks[2], {0, 0}, {limit=1})
+    eq({{marks[2], positions[2][1], positions[2][2]}}, rv)
+    -- prev with positional when mark exists at position
+    rv = get_extmarks(ns, positions[3], {0, 0}, {limit=1})
+    eq({{marks[3], positions[3][1], positions[3][2]}}, rv)
+    -- prev with positional index (no mark at position)
+    rv = get_extmarks(ns, {positions[1][1], positions[1][2] +1}, {0, 0}, {limit=1})
+    eq({{marks[1], positions[1][1], positions[1][2]}}, rv)
+    -- prev with Extremity index
+    rv = get_extmarks(ns, {-1,-1}, {0,0}, {limit=1})
+    eq({{marks[3], positions[3][1], positions[3][2]}}, rv)
+
+    -- prevrange with mark id
+    rv = get_extmarks(ns, marks[3], marks[1])
+    eq({marks[3], positions[3][1], positions[3][2]}, rv[1])
+    eq({marks[2], positions[2][1], positions[2][2]}, rv[2])
+    eq({marks[1], positions[1][1], positions[1][2]}, rv[3])
+    -- prevrange with limit
+    rv = get_extmarks(ns, marks[3], marks[1], {limit=2})
+    eq(2, table.getn(rv))
+    -- prevrange with positional when mark exists at position
+    rv = get_extmarks(ns, positions[3], positions[1])
+    eq({{marks[3], positions[3][1], positions[3][2]},
+        {marks[2], positions[2][1], positions[2][2]},
+        {marks[1], positions[1][1], positions[1][2]}}, rv)
+    rv = get_extmarks(ns, positions[2], positions[1])
+    eq(2, table.getn(rv))
+    -- prevrange with positional index (no mark at position)
+    lower = {positions[2][1], positions[2][2] + 1}
+    upper = {positions[3][1], positions[3][2] + 1}
+    rv = get_extmarks(ns, upper, lower)
+    eq({{marks[3], positions[3][1], positions[3][2]}}, rv)
+    lower = {positions[3][1], positions[3][2] + 1}
+    upper = {positions[3][1], positions[3][2] + 2}
+    rv = get_extmarks(ns, upper, lower)
+    eq({}, rv)
+    -- prevrange with extremity index
+    lower = {0,0}
+    upper = {positions[2][1], positions[2][2] - 1}
+    rv = get_extmarks(ns, upper, lower)
+    eq({{marks[1], positions[1][1], positions[1][2]}}, rv)
+  end)
+
+  it('querying for information with limit', function()
+    -- add some more marks
+    for i, m in ipairs(marks) do
+      if positions[i] ~= nil then
+        local rv = set_extmark(ns, m, positions[i][1], positions[i][2])
+        eq(m, rv)
+      end
+    end
+
+    local rv = get_extmarks(ns, {0, 0}, {-1, -1}, {limit=1})
+    eq(1, table.getn(rv))
+    rv = get_extmarks(ns, {0, 0}, {-1, -1}, {limit=2})
+    eq(2, table.getn(rv))
+    rv = get_extmarks(ns, {0, 0}, {-1, -1}, {limit=3})
+    eq(3, table.getn(rv))
+
+    -- now in reverse
+    rv = get_extmarks(ns, {0, 0}, {-1, -1}, {limit=1})
+    eq(1, table.getn(rv))
+    rv = get_extmarks(ns, {0, 0}, {-1, -1}, {limit=2})
+    eq(2, table.getn(rv))
+    rv = get_extmarks(ns, {0, 0}, {-1, -1}, {limit=3})
+    eq(3, table.getn(rv))
+  end)
+
+  it('get_marks works when mark col > upper col', function()
+    feed('A<cr>12345<esc>')
+    feed('A<cr>12345<esc>')
+    set_extmark(ns, 10, 0, 2)       -- this shouldn't be found
+    set_extmark(ns, 11, 2, 1)       -- this shouldn't be found
+    set_extmark(ns, marks[1], 0, 4) -- check col > our upper bound
+    set_extmark(ns, marks[2], 1, 1) -- check col < lower bound
+    set_extmark(ns, marks[3], 2, 0) -- check is inclusive
+    eq({{marks[1], 0, 4},
+        {marks[2], 1, 1},
+        {marks[3], 2, 0}},
+       get_extmarks(ns, {0, 3}, {2, 0}))
+  end)
+
+  it('get_marks works in reverse when mark col < lower col', function()
+    feed('A<cr>12345<esc>')
+    feed('A<cr>12345<esc>')
+    set_extmark(ns, 10, 0, 1) -- this shouldn't be found
+    set_extmark(ns, 11, 2, 4) -- this shouldn't be found
+    set_extmark(ns, marks[1], 2, 1) -- check col < our lower bound
+    set_extmark(ns, marks[2], 1, 4) -- check col > upper bound
+    set_extmark(ns, marks[3], 0, 2) -- check is inclusive
+    local rv = get_extmarks(ns, {2, 3}, {0, 2})
+    eq({{marks[1], 2, 1},
+        {marks[2], 1, 4},
+        {marks[3], 0, 2}},
+       rv)
+  end)
+
+  it('get_marks limit=0 returns nothing', function()
+    set_extmark(ns, marks[1], positions[1][1], positions[1][2])
+    local rv = get_extmarks(ns, {-1, -1}, {-1, -1}, {limit=0})
+    eq({}, rv)
+  end)
+
+
+  it('marks move with line insertations', function()
+    set_extmark(ns, marks[1], 0, 0)
+    feed("yyP")
+    check_undo_redo(ns, marks[1], 0, 0, 1, 0)
+  end)
+
+  it('marks move with multiline insertations', function()
+    feed("a<cr>22<cr>33<esc>")
+    set_extmark(ns, marks[1], 1, 1)
+    feed('ggVGyP')
+    check_undo_redo(ns, marks[1], 1, 1, 4, 1)
+  end)
+
+  it('marks move with line join', function()
+    -- do_join in ops.c
+    feed("a<cr>222<esc>")
+    set_extmark(ns, marks[1], 1, 0)
+    feed('ggJ')
+    check_undo_redo(ns, marks[1], 1, 0, 0, 6)
+  end)
+
+  it('join works when no marks are present', function()
+    screen = Screen.new(15, 10)
+    screen:attach()
+    feed("a<cr>1<esc>")
+    feed('kJ')
+    -- This shouldn't seg fault
+    screen:expect([[
+      12345^ 1        |
+      ~              |
+      ~              |
+      ~              |
+      ~              |
+      ~              |
+      ~              |
+      ~              |
+      ~              |
+                     |
+    ]])
+  end)
+
+  it('marks move with multiline join', function()
+    -- do_join in ops.c
+    feed("a<cr>222<cr>333<cr>444<esc>")
+    set_extmark(ns, marks[1], 3, 0)
+    feed('2GVGJ')
+    check_undo_redo(ns, marks[1], 3, 0, 1, 8)
+  end)
+
+  it('marks move with line deletes', function()
+    feed("a<cr>222<cr>333<cr>444<esc>")
+    set_extmark(ns, marks[1], 2, 1)
+    feed('ggjdd')
+    check_undo_redo(ns, marks[1], 2, 1, 1, 1)
+  end)
+
+  it('marks move with multiline deletes', function()
+    feed("a<cr>222<cr>333<cr>444<esc>")
+    set_extmark(ns, marks[1], 3, 0)
+    feed('gg2dd')
+    check_undo_redo(ns, marks[1], 3, 0, 1, 0)
+    -- regression test, undoing multiline delete when mark is on row 1
+    feed('ugg3dd')
+    check_undo_redo(ns, marks[1], 3, 0, 0, 0)
+  end)
+
+  it('marks move with open line', function()
+    -- open_line in misc1.c
+    -- testing marks below are also moved
+    feed("yyP")
+    set_extmark(ns, marks[1], 0, 4)
+    set_extmark(ns, marks[2], 1, 4)
+    feed('1G<s-o><esc>')
+    check_undo_redo(ns, marks[1], 0, 4, 1, 4)
+    check_undo_redo(ns, marks[2], 1, 4, 2, 4)
+    feed('2Go<esc>')
+    check_undo_redo(ns, marks[1], 1, 4, 1, 4)
+    check_undo_redo(ns, marks[2], 2, 4, 3, 4)
+  end)
+
+  it('marks move with char inserts', function()
+    -- insertchar in edit.c (the ins_str branch)
+    screen = Screen.new(15, 10)
+    screen:attach()
+    set_extmark(ns, marks[1], 0, 3)
+    feed('0')
+    insert('abc')
+    screen:expect([[
+      ab^c12345       |
+      ~              |
+      ~              |
+      ~              |
+      ~              |
+      ~              |
+      ~              |
+      ~              |
+      ~              |
+                     |
+    ]])
+    local rv = curbufmeths.get_extmark_by_id(ns, marks[1])
+    eq({0, 6}, rv)
+    check_undo_redo(ns, marks[1], 0, 3, 0, 6)
+  end)
+
+  -- gravity right as definted in tk library
+  it('marks have gravity right', function()
+    -- insertchar in edit.c (the ins_str branch)
+    set_extmark(ns, marks[1], 0, 2)
+    feed('03l')
+    insert("X")
+    check_undo_redo(ns, marks[1], 0, 2, 0, 2)
+
+    -- check multibyte chars
+    feed('03l<esc>')
+    insert("～～")
+    check_undo_redo(ns, marks[1], 0, 2, 0, 2)
+  end)
+
+  it('we can insert multibyte chars', function()
+    -- insertchar in edit.c
+    feed('a<cr>12345<esc>')
+    set_extmark(ns, marks[1], 1, 2)
+    -- Insert a fullwidth (two col) tilde, NICE
+    feed('0i～<esc>')
+    check_undo_redo(ns, marks[1], 1, 2, 1, 5)
+  end)
+
+  it('marks move with blockwise inserts', function()
+    -- op_insert in ops.c
+    feed('a<cr>12345<esc>')
+    set_extmark(ns, marks[1], 1, 2)
+    feed('0<c-v>lkI9<esc>')
+    check_undo_redo(ns, marks[1], 1, 2, 1, 3)
+  end)
+
+  it('marks move with line splits (using enter)', function()
+    -- open_line in misc1.c
+    -- testing marks below are also moved
+    feed("yyP")
+    set_extmark(ns, marks[1], 0, 4)
+    set_extmark(ns, marks[2], 1, 4)
+    feed('1Gla<cr><esc>')
+    check_undo_redo(ns, marks[1], 0, 4, 1, 2)
+    check_undo_redo(ns, marks[2], 1, 4, 2, 4)
+  end)
+
+  it('marks at last line move on insert new line', function()
+    -- open_line in misc1.c
+    set_extmark(ns, marks[1], 0, 4)
+    feed('0i<cr><esc>')
+    check_undo_redo(ns, marks[1], 0, 4, 1, 4)
+  end)
+
+  it('yet again marks move with line splits', function()
+    -- the first test above wasn't catching all errors..
+    feed("A67890<esc>")
+    set_extmark(ns, marks[1], 0, 4)
+    feed("04li<cr><esc>")
+    check_undo_redo(ns, marks[1], 0, 4, 1, 0)
+  end)
+
+  it('and one last time line splits...', function()
+    set_extmark(ns, marks[1], 0, 1)
+    set_extmark(ns, marks[2], 0, 2)
+    feed("02li<cr><esc>")
+    check_undo_redo(ns, marks[1], 0, 1, 0, 1)
+    check_undo_redo(ns, marks[2], 0, 2, 1, 0)
+  end)
+
+  it('multiple marks move with mark splits', function()
+    set_extmark(ns, marks[1], 0, 1)
+    set_extmark(ns, marks[2], 0, 3)
+    feed("0li<cr><esc>")
+    check_undo_redo(ns, marks[1], 0, 1, 1, 0)
+    check_undo_redo(ns, marks[2], 0, 3, 1, 2)
+  end)
+
+  it('deleting right before a mark works', function()
+    -- op_delete in ops.c
+    set_extmark(ns, marks[1], 0, 2)
+    feed('0lx')
+    check_undo_redo(ns, marks[1], 0, 2, 0, 1)
+  end)
+
+  it('deleting right after a mark works', function()
+    -- op_delete in ops.c
+    set_extmark(ns, marks[1], 0, 2)
+    feed('02lx')
+    check_undo_redo(ns, marks[1], 0, 2, 0, 2)
+  end)
+
+  it('marks move with char deletes', function()
+    -- op_delete in ops.c
+    set_extmark(ns, marks[1], 0, 2)
+    feed('02dl')
+    check_undo_redo(ns, marks[1], 0, 2, 0, 0)
+    -- from the other side (nothing should happen)
+    feed('$x')
+    check_undo_redo(ns, marks[1], 0, 0, 0, 0)
+  end)
+
+  it('marks move with char deletes over a range', function()
+    -- op_delete in ops.c
+    set_extmark(ns, marks[1], 0, 2)
+    set_extmark(ns, marks[2], 0, 3)
+    feed('0l3dl<esc>')
+    check_undo_redo(ns, marks[1], 0, 2, 0, 1)
+    check_undo_redo(ns, marks[2], 0, 3, 0, 1)
+    -- delete 1, nothing should happen to our marks
+    feed('u')
+    feed('$x')
+    check_undo_redo(ns, marks[2], 0, 3, 0, 3)
+  end)
+
+  it('deleting marks at end of line works', function()
+    set_extmark(ns, marks[1], 0, 4)
+    feed('$x')
+    check_undo_redo(ns, marks[1], 0, 4, 0, 4)
+    -- check the copy happened correctly on delete at eol
+    feed('$x')
+    check_undo_redo(ns, marks[1], 0, 4, 0, 3)
+    feed('u')
+    check_undo_redo(ns, marks[1], 0, 4, 0, 4)
+  end)
+
+  it('marks move with blockwise deletes', function()
+    -- op_delete in ops.c
+    feed('a<cr>12345<esc>')
+    set_extmark(ns, marks[1], 1, 4)
+    feed('h<c-v>hhkd')
+    check_undo_redo(ns, marks[1], 1, 4, 1, 1)
+  end)
+
+  it('marks move with blockwise deletes over a range', function()
+    -- op_delete in ops.c
+    feed('a<cr>12345<esc>')
+    set_extmark(ns, marks[1], 0, 1)
+    set_extmark(ns, marks[2], 0, 3)
+    set_extmark(ns, marks[3], 1, 2)
+    feed('0<c-v>k3lx')
+    check_undo_redo(ns, marks[1], 0, 1, 0, 0)
+    check_undo_redo(ns, marks[2], 0, 3, 0, 0)
+    check_undo_redo(ns, marks[3], 1, 2, 1, 0)
+    -- delete 1, nothing should happen to our marks
+    feed('u')
+    feed('$<c-v>jx')
+    check_undo_redo(ns, marks[2], 0, 3, 0, 3)
+    check_undo_redo(ns, marks[3], 1, 2, 1, 2)
+  end)
+
+  it('works with char deletes over multilines', function()
+    feed('a<cr>12345<cr>test-me<esc>')
+    set_extmark(ns, marks[1], 2, 5)
+    feed('gg')
+    feed('dv?-m?<cr>')
+    check_undo_redo(ns, marks[1], 2, 5, 0, 0)
+  end)
+
+  it('marks outside of deleted range move with visual char deletes', function()
+    -- op_delete in ops.c
+    set_extmark(ns, marks[1], 0, 3)
+    feed('0vx<esc>')
+    check_undo_redo(ns, marks[1], 0, 3, 0, 2)
+
+    feed("u")
+    feed('0vlx<esc>')
+    check_undo_redo(ns, marks[1], 0, 3, 0, 1)
+
+    feed("u")
+    feed('0v2lx<esc>')
+    check_undo_redo(ns, marks[1], 0, 3, 0, 0)
+
+    -- from the other side (nothing should happen)
+    feed('$vx')
+    check_undo_redo(ns, marks[1], 0, 0, 0, 0)
+  end)
+
+  it('marks outside of deleted range move with char deletes', function()
+    -- op_delete in ops.c
+    set_extmark(ns, marks[1], 0, 3)
+    feed('0x<esc>')
+    check_undo_redo(ns, marks[1], 0, 3, 0, 2)
+
+    feed("u")
+    feed('02x<esc>')
+    check_undo_redo(ns, marks[1], 0, 3, 0, 1)
+
+    feed("u")
+    feed('0v3lx<esc>')
+    check_undo_redo(ns, marks[1], 0, 3, 0, 0)
+
+    -- from the other side (nothing should happen)
+    feed("u")
+    feed('$vx')
+    check_undo_redo(ns, marks[1], 0, 3, 0, 3)
+  end)
+
+  it('marks move with P(backward) paste', function()
+    -- do_put in ops.c
+    feed('0iabc<esc>')
+    set_extmark(ns, marks[1], 0, 7)
+    feed('0veyP')
+    check_undo_redo(ns, marks[1], 0, 7, 0, 15)
+  end)
+
+  it('marks move with p(forward) paste', function()
+    -- do_put in ops.c
+    feed('0iabc<esc>')
+    set_extmark(ns, marks[1], 0, 7)
+    feed('0veyp')
+    check_undo_redo(ns, marks[1], 0, 7, 0, 15)
+  end)
+
+  it('marks move with blockwise P(backward) paste', function()
+    -- do_put in ops.c
+    feed('a<cr>12345<esc>')
+    set_extmark(ns, marks[1], 1, 4)
+    feed('<c-v>hhkyP<esc>')
+    check_undo_redo(ns, marks[1], 1, 4, 1, 7)
+  end)
+
+  it('marks move with blockwise p(forward) paste', function()
+    -- do_put in ops.c
+    feed('a<cr>12345<esc>')
+    set_extmark(ns, marks[1], 1, 4)
+    feed('<c-v>hhkyp<esc>')
+    check_undo_redo(ns, marks[1], 1, 4, 1, 7)
+  end)
+
+  describe('multiline regions', function()
+    before_each(function()
+      feed('dd')
+      -- Achtung: code has been spiced with some unicode,
+      -- to make life more interesting.
+      -- luacheck whines about TABs inside strings for whatever reason.
+      -- luacheck: push ignore 621
+      insert([[
+        static int nlua_rpcrequest(lua_State *lstate)
+        {
+          Ïf (!nlua_is_deferred_safe(lstate)) {
+        	// strictly not allowed
+            Яetörn luaL_error(lstate, e_luv_api_disabled, "rpcrequest");
+          }
+          return nlua_rpc(lstate, true);
+        }]])
+      -- luacheck: pop
+    end)
+
+    it('delete', function()
+      local pos1 = {
+        {2, 4}, {2, 12}, {2, 13}, {2, 14}, {2, 25},
+        {4, 8}, {4, 10}, {4, 20},
+        {5, 3}, {6, 10}
+      }
+      local ids = batch_set(ns, pos1)
+      batch_check(ns, ids, pos1)
+      feed('3Gfiv2+ftd')
+      batch_check_undo_redo(ns, ids, pos1, {
+        {2, 4}, {2, 12}, {2, 13}, {2, 13}, {2, 13},
+        {2, 13}, {2, 15}, {2, 25},
+        {3, 3}, {4, 10}
+      })
+    end)
+
+    -- TODO(bfredl): add more tests!
+  end)
+
+  it('replace works', function()
+    set_extmark(ns, marks[1], 0, 2)
+    feed('0r2')
+    check_undo_redo(ns, marks[1], 0, 2, 0, 2)
+  end)
+
+  it('blockwise replace works', function()
+    feed('a<cr>12345<esc>')
+    set_extmark(ns, marks[1], 0, 2)
+    feed('0<c-v>llkr1<esc>')
+    check_undo_redo(ns, marks[1], 0, 2, 0, 3)
+  end)
+
+  it('shift line', function()
+    -- shift_line in ops.c
+    feed(':set shiftwidth=4<cr><esc>')
+    set_extmark(ns, marks[1], 0, 2)
+    feed('0>>')
+    check_undo_redo(ns, marks[1], 0, 2, 0, 6)
+    expect('    12345')
+
+    feed('>>')
+    -- this is counter-intuitive. But what happens
+    -- is that 4 spaces gets extended to one tab (== 8 spaces)
+    check_undo_redo(ns, marks[1], 0, 6, 0, 3)
+    expect('\t12345')
+
+    feed('<LT><LT>') -- have to escape, same as <<
+    check_undo_redo(ns, marks[1], 0, 3, 0, 6)
+  end)
+
+  it('blockwise shift', function()
+    -- shift_block in ops.c
+    feed(':set shiftwidth=4<cr><esc>')
+    feed('a<cr>12345<esc>')
+    set_extmark(ns, marks[1], 1, 2)
+    feed('0<c-v>k>')
+    check_undo_redo(ns, marks[1], 1, 2, 1, 6)
+    feed('<c-v>j>')
+    expect('\t12345\n\t12345')
+    check_undo_redo(ns, marks[1], 1, 6, 1, 3)
+
+    feed('<c-v>j<LT>')
+    check_undo_redo(ns, marks[1], 1, 3, 1, 6)
+  end)
+
+  it('tab works with expandtab', function()
+    -- ins_tab in edit.c
+    feed(':set expandtab<cr><esc>')
+    feed(':set shiftwidth=2<cr><esc>')
+    set_extmark(ns, marks[1], 0, 2)
+    feed('0i<tab><tab><esc>')
+    check_undo_redo(ns, marks[1], 0, 2, 0, 6)
+  end)
+
+  it('tabs work', function()
+    -- ins_tab in edit.c
+    feed(':set noexpandtab<cr><esc>')
+    feed(':set shiftwidth=2<cr><esc>')
+    feed(':set softtabstop=2<cr><esc>')
+    feed(':set tabstop=8<cr><esc>')
+    set_extmark(ns, marks[1], 0, 2)
+    feed('0i<tab><esc>')
+    check_undo_redo(ns, marks[1], 0, 2, 0, 4)
+    feed('0iX<tab><esc>')
+    check_undo_redo(ns, marks[1], 0, 4, 0, 6)
+  end)
+
+  it('marks move when using :move', function()
+    set_extmark(ns, marks[1], 0, 0)
+    feed('A<cr>2<esc>:1move 2<cr><esc>')
+    check_undo_redo(ns, marks[1], 0, 0, 1, 0)
+    -- test codepath when moving lines up
+    feed(':2move 0<cr><esc>')
+    check_undo_redo(ns, marks[1], 1, 0, 0, 0)
+  end)
+
+  it('marks move when using :move part 2', function()
+    -- make sure we didn't get lucky with the math...
+    feed('A<cr>2<cr>3<cr>4<cr>5<cr>6<esc>')
+    set_extmark(ns, marks[1], 1, 0)
+    feed(':2,3move 5<cr><esc>')
+    check_undo_redo(ns, marks[1], 1, 0, 3, 0)
+    -- test codepath when moving lines up
+    feed(':4,5move 1<cr><esc>')
+    check_undo_redo(ns, marks[1], 3, 0, 1, 0)
+  end)
+
+  it('undo and redo of set and unset marks', function()
+    -- Force a new undo head
+    feed('o<esc>')
+    set_extmark(ns, marks[1], 0, 1)
+    feed('o<esc>')
+    set_extmark(ns, marks[2], 0, -1)
+    set_extmark(ns, marks[3], 0, -1)
+
+    feed("u")
+    local rv = get_extmarks(ns, {0, 0}, {-1, -1})
+    eq(3, table.getn(rv))
+
+    feed("<c-r>")
+    rv = get_extmarks(ns, {0, 0}, {-1, -1})
+    eq(3, table.getn(rv))
+
+    -- Test updates
+    feed('o<esc>')
+    set_extmark(ns, marks[1], positions[1][1], positions[1][2])
+    rv = get_extmarks(ns, marks[1], marks[1], {limit=1})
+    eq(1, table.getn(rv))
+    feed("u")
+    feed("<c-r>")
+    -- old value is NOT kept in history
+    check_undo_redo(ns, marks[1], positions[1][1], positions[1][2], positions[1][1], positions[1][2])
+
+    -- Test unset
+    feed('o<esc>')
+    curbufmeths.del_extmark(ns, marks[3])
+    feed("u")
+    rv = get_extmarks(ns, {0, 0}, {-1, -1})
+    -- undo does NOT restore deleted marks
+    eq(2, table.getn(rv))
+    feed("<c-r>")
+    rv = get_extmarks(ns, {0, 0}, {-1, -1})
+    eq(2, table.getn(rv))
+  end)
+
+  it('undo and redo of marks deleted during edits', function()
+    -- test extmark_adjust
+    feed('A<cr>12345<esc>')
+    set_extmark(ns, marks[1], 1, 2)
+    feed('dd')
+    check_undo_redo(ns, marks[1], 1, 2, 1, 0)
+  end)
+
+  it('namespaces work properly', function()
+    local rv = set_extmark(ns, marks[1], positions[1][1], positions[1][2])
+    eq(1, rv)
+    rv = set_extmark(ns2, marks[1], positions[1][1], positions[1][2])
+    eq(1, rv)
+    rv = get_extmarks(ns, {0, 0}, {-1, -1})
+    eq(1, table.getn(rv))
+    rv = get_extmarks(ns2, {0, 0}, {-1, -1})
+    eq(1, table.getn(rv))
+
+    -- Set more marks for testing the ranges
+    set_extmark(ns, marks[2], positions[2][1], positions[2][2])
+    set_extmark(ns, marks[3], positions[3][1], positions[3][2])
+    set_extmark(ns2, marks[2], positions[2][1], positions[2][2])
+    set_extmark(ns2, marks[3], positions[3][1], positions[3][2])
+
+    -- get_next (limit set)
+    rv = get_extmarks(ns, {0, 0}, positions[2], {limit=1})
+    eq(1, table.getn(rv))
+    rv = get_extmarks(ns2, {0, 0}, positions[2], {limit=1})
+    eq(1, table.getn(rv))
+    -- get_prev (limit set)
+    rv = get_extmarks(ns, positions[1], {0, 0}, {limit=1})
+    eq(1, table.getn(rv))
+    rv = get_extmarks(ns2, positions[1], {0, 0}, {limit=1})
+    eq(1, table.getn(rv))
+
+    -- get_next (no limit)
+    rv = get_extmarks(ns, positions[1], positions[2])
+    eq(2, table.getn(rv))
+    rv = get_extmarks(ns2, positions[1], positions[2])
+    eq(2, table.getn(rv))
+    -- get_prev (no limit)
+    rv = get_extmarks(ns, positions[2], positions[1])
+    eq(2, table.getn(rv))
+    rv = get_extmarks(ns2, positions[2], positions[1])
+    eq(2, table.getn(rv))
+
+    curbufmeths.del_extmark(ns, marks[1])
+    rv = get_extmarks(ns, {0, 0}, {-1, -1})
+    eq(2, table.getn(rv))
+    curbufmeths.del_extmark(ns2, marks[1])
+    rv = get_extmarks(ns2, {0, 0}, {-1, -1})
+    eq(2, table.getn(rv))
+  end)
+
+  it('mark set can create unique identifiers', function()
+    -- create mark with id 1
+    eq(1, set_extmark(ns, 1, positions[1][1], positions[1][2]))
+    -- ask for unique id, it should be the next one, i e 2
+    eq(2, set_extmark(ns, 0, positions[1][1], positions[1][2]))
+    eq(3, set_extmark(ns, 3, positions[2][1], positions[2][2]))
+    eq(4, set_extmark(ns, 0, positions[1][1], positions[1][2]))
+
+    -- mixing manual and allocated id:s are not recommened, but it should
+    -- do something reasonable
+    eq(6, set_extmark(ns, 6, positions[2][1], positions[2][2]))
+    eq(7, set_extmark(ns, 0, positions[1][1], positions[1][2]))
+    eq(8, set_extmark(ns, 0, positions[1][1], positions[1][2]))
+  end)
+
+  it('auto indenting with enter works', function()
+    -- op_reindent in ops.c
+    feed(':set cindent<cr><esc>')
+    feed(':set autoindent<cr><esc>')
+    feed(':set shiftwidth=2<cr><esc>')
+    feed("0iint <esc>A {1M1<esc>b<esc>")
+    -- Set the mark on the M, should move..
+    set_extmark(ns, marks[1], 0, 12)
+    -- Set the mark before the cursor, should stay there
+    set_extmark(ns, marks[2], 0, 10)
+    feed("i<cr><esc>")
+    local rv = curbufmeths.get_extmark_by_id(ns, marks[1])
+    eq({1, 3}, rv)
+    rv = curbufmeths.get_extmark_by_id(ns, marks[2])
+    eq({0, 10}, rv)
+    check_undo_redo(ns, marks[1], 0, 12, 1, 3)
+  end)
+
+  it('auto indenting entire line works', function()
+    feed(':set cindent<cr><esc>')
+    feed(':set autoindent<cr><esc>')
+    feed(':set shiftwidth=2<cr><esc>')
+    -- <c-f> will force an indent of 2
+    feed("0iint <esc>A {<cr><esc>0i1M1<esc>")
+    set_extmark(ns, marks[1], 1, 1)
+    feed("0i<c-f><esc>")
+    local rv = curbufmeths.get_extmark_by_id(ns, marks[1])
+    eq({1, 3}, rv)
+    check_undo_redo(ns, marks[1], 1, 1, 1, 3)
+    -- now check when cursor at eol
+    feed("uA<c-f><esc>")
+    rv = curbufmeths.get_extmark_by_id(ns, marks[1])
+    eq({1, 3}, rv)
+  end)
+
+  it('removing auto indenting with <C-D> works', function()
+    feed(':set cindent<cr><esc>')
+    feed(':set autoindent<cr><esc>')
+    feed(':set shiftwidth=2<cr><esc>')
+    feed("0i<tab><esc>")
+    set_extmark(ns, marks[1], 0, 3)
+    feed("bi<c-d><esc>")
+    local rv = curbufmeths.get_extmark_by_id(ns, marks[1])
+    eq({0, 1}, rv)
+    check_undo_redo(ns, marks[1], 0, 3, 0, 1)
+    -- check when cursor at eol
+    feed("uA<c-d><esc>")
+    rv = curbufmeths.get_extmark_by_id(ns, marks[1])
+    eq({0, 1}, rv)
+  end)
+
+  it('indenting multiple lines with = works', function()
+    feed(':set cindent<cr><esc>')
+    feed(':set autoindent<cr><esc>')
+    feed(':set shiftwidth=2<cr><esc>')
+    feed("0iint <esc>A {<cr><bs>1M1<cr><bs>2M2<esc>")
+    set_extmark(ns, marks[1], 1, 1)
+    set_extmark(ns, marks[2], 2, 1)
+    feed('=gg')
+    check_undo_redo(ns, marks[1], 1, 1, 1, 3)
+    check_undo_redo(ns, marks[2], 2, 1, 2, 5)
+  end)
+
+  it('substitutes by deleting inside the replace matches', function()
+    -- do_sub in ex_cmds.c
+    set_extmark(ns, marks[1], 0, 2)
+    set_extmark(ns, marks[2], 0, 3)
+    feed(':s/34/xx<cr>')
+    check_undo_redo(ns, marks[1], 0, 2, 0, 4)
+    check_undo_redo(ns, marks[2], 0, 3, 0, 4)
+  end)
+
+  it('substitutes when insert text > deleted', function()
+    -- do_sub in ex_cmds.c
+    set_extmark(ns, marks[1], 0, 2)
+    set_extmark(ns, marks[2], 0, 3)
+    feed(':s/34/xxx<cr>')
+    check_undo_redo(ns, marks[1], 0, 2, 0, 5)
+    check_undo_redo(ns, marks[2], 0, 3, 0, 5)
+  end)
+
+  it('substitutes when marks around eol', function()
+    -- do_sub in ex_cmds.c
+    set_extmark(ns, marks[1], 0, 4)
+    set_extmark(ns, marks[2], 0, 5)
+    feed(':s/5/xxx<cr>')
+    check_undo_redo(ns, marks[1], 0, 4, 0, 7)
+    check_undo_redo(ns, marks[2], 0, 5, 0, 7)
+  end)
+
+  it('substitutes over range insert text > deleted', function()
+    -- do_sub in ex_cmds.c
+    feed('A<cr>x34xx<esc>')
+    feed('A<cr>xxx34<esc>')
+    set_extmark(ns, marks[1], 0, 2)
+    set_extmark(ns, marks[2], 1, 1)
+    set_extmark(ns, marks[3], 2, 4)
+    feed(':1,3s/34/xxx<cr><esc>')
+    check_undo_redo(ns, marks[1], 0, 2, 0, 5)
+    check_undo_redo(ns, marks[2], 1, 1, 1, 4)
+    check_undo_redo(ns, marks[3], 2, 4, 2, 6)
+  end)
+
+  it('substitutes multiple matches in a line', function()
+    -- do_sub in ex_cmds.c
+    feed('ddi3x3x3<esc>')
+    set_extmark(ns, marks[1], 0, 0)
+    set_extmark(ns, marks[2], 0, 2)
+    set_extmark(ns, marks[3], 0, 4)
+    feed(':s/3/yy/g<cr><esc>')
+    check_undo_redo(ns, marks[1], 0, 0, 0, 2)
+    check_undo_redo(ns, marks[2], 0, 2, 0, 5)
+    check_undo_redo(ns, marks[3], 0, 4, 0, 8)
+  end)
+
+  it('substitions over multiple lines with newline in pattern', function()
+    feed('A<cr>67890<cr>xx<esc>')
+    set_extmark(ns, marks[1], 0, 3)
+    set_extmark(ns, marks[2], 0, 4)
+    set_extmark(ns, marks[3], 1, 0)
+    set_extmark(ns, marks[4], 1, 5)
+    set_extmark(ns, marks[5], 2, 0)
+    feed([[:1,2s:5\n:5 <cr>]])
+    check_undo_redo(ns, marks[1], 0, 3, 0, 3)
+    check_undo_redo(ns, marks[2], 0, 4, 0, 6)
+    check_undo_redo(ns, marks[3], 1, 0, 0, 6)
+    check_undo_redo(ns, marks[4], 1, 5, 0, 11)
+    check_undo_redo(ns, marks[5], 2, 0, 1, 0)
+  end)
+
+  it('inserting', function()
+    feed('A<cr>67890<cr>xx<esc>')
+    set_extmark(ns, marks[1], 0, 3)
+    set_extmark(ns, marks[2], 0, 4)
+    set_extmark(ns, marks[3], 1, 0)
+    set_extmark(ns, marks[4], 1, 5)
+    set_extmark(ns, marks[5], 2, 0)
+    set_extmark(ns, marks[6], 1, 2)
+    feed([[:1,2s:5\n67:X<cr>]])
+    check_undo_redo(ns, marks[1], 0, 3, 0, 3)
+    check_undo_redo(ns, marks[2], 0, 4, 0, 5)
+    check_undo_redo(ns, marks[3], 1, 0, 0, 5)
+    check_undo_redo(ns, marks[4], 1, 5, 0, 8)
+    check_undo_redo(ns, marks[5], 2, 0, 1, 0)
+    check_undo_redo(ns, marks[6], 1, 2, 0, 5)
+  end)
+
+  it('substitions with multiple newlines in pattern', function()
+    feed('A<cr>67890<cr>xx<esc>')
+    set_extmark(ns, marks[1], 0, 4)
+    set_extmark(ns, marks[2], 0, 5)
+    set_extmark(ns, marks[3], 1, 0)
+    set_extmark(ns, marks[4], 1, 5)
+    set_extmark(ns, marks[5], 2, 0)
+    feed([[:1,2s:\n.*\n:X<cr>]])
+    check_undo_redo(ns, marks[1], 0, 4, 0, 4)
+    check_undo_redo(ns, marks[2], 0, 5, 0, 6)
+    check_undo_redo(ns, marks[3], 1, 0, 0, 6)
+    check_undo_redo(ns, marks[4], 1, 5, 0, 6)
+    check_undo_redo(ns, marks[5], 2, 0, 0, 6)
+  end)
+
+  it('substitions over multiple lines with replace in substition', function()
+    feed('A<cr>67890<cr>xx<esc>')
+    set_extmark(ns, marks[1], 0, 1)
+    set_extmark(ns, marks[2], 0, 2)
+    set_extmark(ns, marks[3], 0, 4)
+    set_extmark(ns, marks[4], 1, 0)
+    set_extmark(ns, marks[5], 2, 0)
+    feed([[:1,2s:3:\r<cr>]])
+    check_undo_redo(ns, marks[1], 0, 1, 0, 1)
+    check_undo_redo(ns, marks[2], 0, 2, 1, 0)
+    check_undo_redo(ns, marks[3], 0, 4, 1, 1)
+    check_undo_redo(ns, marks[4], 1, 0, 2, 0)
+    check_undo_redo(ns, marks[5], 2, 0, 3, 0)
+    feed('u')
+    feed([[:1,2s:3:\rxx<cr>]])
+    eq({1, 3}, curbufmeths.get_extmark_by_id(ns, marks[3]))
+  end)
+
+  it('substitions over multiple lines with replace in substition', function()
+    feed('A<cr>x3<cr>xx<esc>')
+    set_extmark(ns, marks[1], 1, 0)
+    set_extmark(ns, marks[2], 1, 1)
+    set_extmark(ns, marks[3], 1, 2)
+    feed([[:2,2s:3:\r<cr>]])
+    check_undo_redo(ns, marks[1], 1, 0, 1, 0)
+    check_undo_redo(ns, marks[2], 1, 1, 2, 0)
+    check_undo_redo(ns, marks[3], 1, 2, 2, 0)
+  end)
+
+  it('substitions over multiple lines with replace in substition', function()
+    feed('A<cr>x3<cr>xx<esc>')
+    set_extmark(ns, marks[1], 0, 1)
+    set_extmark(ns, marks[2], 0, 2)
+    set_extmark(ns, marks[3], 0, 4)
+    set_extmark(ns, marks[4], 1, 1)
+    set_extmark(ns, marks[5], 2, 0)
+    feed([[:1,2s:3:\r<cr>]])
+    check_undo_redo(ns, marks[1], 0, 1, 0, 1)
+    check_undo_redo(ns, marks[2], 0, 2, 1, 0)
+    check_undo_redo(ns, marks[3], 0, 4, 1, 1)
+    check_undo_redo(ns, marks[4], 1, 1, 3, 0)
+    check_undo_redo(ns, marks[5], 2, 0, 4, 0)
+    feed('u')
+    feed([[:1,2s:3:\rxx<cr>]])
+    check_undo_redo(ns, marks[3], 0, 4, 1, 3)
+  end)
+
+  it('substitions with newline in match and sub, delta is 0', function()
+    feed('A<cr>67890<cr>xx<esc>')
+    set_extmark(ns, marks[1], 0, 3)
+    set_extmark(ns, marks[2], 0, 4)
+    set_extmark(ns, marks[3], 0, 5)
+    set_extmark(ns, marks[4], 1, 0)
+    set_extmark(ns, marks[5], 1, 5)
+    set_extmark(ns, marks[6], 2, 0)
+    feed([[:1,1s:5\n:\r<cr>]])
+    check_undo_redo(ns, marks[1], 0, 3, 0, 3)
+    check_undo_redo(ns, marks[2], 0, 4, 1, 0)
+    check_undo_redo(ns, marks[3], 0, 5, 1, 0)
+    check_undo_redo(ns, marks[4], 1, 0, 1, 0)
+    check_undo_redo(ns, marks[5], 1, 5, 1, 5)
+    check_undo_redo(ns, marks[6], 2, 0, 2, 0)
+  end)
+
+  it('substitions with newline in match and sub, delta > 0', function()
+    feed('A<cr>67890<cr>xx<esc>')
+    set_extmark(ns, marks[1], 0, 3)
+    set_extmark(ns, marks[2], 0, 4)
+    set_extmark(ns, marks[3], 0, 5)
+    set_extmark(ns, marks[4], 1, 0)
+    set_extmark(ns, marks[5], 1, 5)
+    set_extmark(ns, marks[6], 2, 0)
+    feed([[:1,1s:5\n:\r\r<cr>]])
+    check_undo_redo(ns, marks[1], 0, 3, 0, 3)
+    check_undo_redo(ns, marks[2], 0, 4, 2, 0)
+    check_undo_redo(ns, marks[3], 0, 5, 2, 0)
+    check_undo_redo(ns, marks[4], 1, 0, 2, 0)
+    check_undo_redo(ns, marks[5], 1, 5, 2, 5)
+    check_undo_redo(ns, marks[6], 2, 0, 3, 0)
+  end)
+
+  it('substitions with newline in match and sub, delta < 0', function()
+    feed('A<cr>67890<cr>xx<cr>xx<esc>')
+    set_extmark(ns, marks[1], 0, 3)
+    set_extmark(ns, marks[2], 0, 4)
+    set_extmark(ns, marks[3], 0, 5)
+    set_extmark(ns, marks[4], 1, 0)
+    set_extmark(ns, marks[5], 1, 5)
+    set_extmark(ns, marks[6], 2, 1)
+    set_extmark(ns, marks[7], 3, 0)
+    feed([[:1,2s:5\n.*\n:\r<cr>]])
+    check_undo_redo(ns, marks[1], 0, 3, 0, 3)
+    check_undo_redo(ns, marks[2], 0, 4, 1, 0)
+    check_undo_redo(ns, marks[3], 0, 5, 1, 0)
+    check_undo_redo(ns, marks[4], 1, 0, 1, 0)
+    check_undo_redo(ns, marks[5], 1, 5, 1, 0)
+    check_undo_redo(ns, marks[6], 2, 1, 1, 1)
+    check_undo_redo(ns, marks[7], 3, 0, 2, 0)
+  end)
+
+  it('substitions with backrefs, newline inserted into sub', function()
+    feed('A<cr>67890<cr>xx<cr>xx<esc>')
+    set_extmark(ns, marks[1], 0, 3)
+    set_extmark(ns, marks[2], 0, 4)
+    set_extmark(ns, marks[3], 0, 5)
+    set_extmark(ns, marks[4], 1, 0)
+    set_extmark(ns, marks[5], 1, 5)
+    set_extmark(ns, marks[6], 2, 0)
+    feed([[:1,1s:5\(\n\):\0\1<cr>]])
+    check_undo_redo(ns, marks[1], 0, 3, 0, 3)
+    check_undo_redo(ns, marks[2], 0, 4, 2, 0)
+    check_undo_redo(ns, marks[3], 0, 5, 2, 0)
+    check_undo_redo(ns, marks[4], 1, 0, 2, 0)
+    check_undo_redo(ns, marks[5], 1, 5, 2, 5)
+    check_undo_redo(ns, marks[6], 2, 0, 3, 0)
+  end)
+
+  it('substitions a ^', function()
+    set_extmark(ns, marks[1], 0, 0)
+    set_extmark(ns, marks[2], 0, 1)
+    feed([[:s:^:x<cr>]])
+    check_undo_redo(ns, marks[1], 0, 0, 0, 1)
+    check_undo_redo(ns, marks[2], 0, 1, 0, 2)
+  end)
+
+  it('using <c-a> without increase in order of magnitude', function()
+    -- do_addsub in ops.c
+    feed('ddiabc998xxx<esc>Tc')
+    set_extmark(ns, marks[1], 0, 2)
+    set_extmark(ns, marks[2], 0, 3)
+    set_extmark(ns, marks[3], 0, 5)
+    set_extmark(ns, marks[4], 0, 6)
+    set_extmark(ns, marks[5], 0, 7)
+    feed('<c-a>')
+    check_undo_redo(ns, marks[1], 0, 2, 0, 2)
+    check_undo_redo(ns, marks[2], 0, 3, 0, 6)
+    check_undo_redo(ns, marks[3], 0, 5, 0, 6)
+    check_undo_redo(ns, marks[4], 0, 6, 0, 6)
+    check_undo_redo(ns, marks[5], 0, 7, 0, 7)
+  end)
+
+  it('using <c-a> when increase in order of magnitude', function()
+    -- do_addsub in ops.c
+    feed('ddiabc999xxx<esc>Tc')
+    set_extmark(ns, marks[1], 0, 2)
+    set_extmark(ns, marks[2], 0, 3)
+    set_extmark(ns, marks[3], 0, 5)
+    set_extmark(ns, marks[4], 0, 6)
+    set_extmark(ns, marks[5], 0, 7)
+    feed('<c-a>')
+    check_undo_redo(ns, marks[1], 0, 2, 0, 2)
+    check_undo_redo(ns, marks[2], 0, 3, 0, 7)
+    check_undo_redo(ns, marks[3], 0, 5, 0, 7)
+    check_undo_redo(ns, marks[4], 0, 6, 0, 7)
+    check_undo_redo(ns, marks[5], 0, 7, 0, 8)
+  end)
+
+  it('using <c-a> when negative and without decrease in order of magnitude', function()
+    feed('ddiabc-999xxx<esc>T-')
+    set_extmark(ns, marks[1], 0, 2)
+    set_extmark(ns, marks[2], 0, 3)
+    set_extmark(ns, marks[3], 0, 6)
+    set_extmark(ns, marks[4], 0, 7)
+    set_extmark(ns, marks[5], 0, 8)
+    feed('<c-a>')
+    check_undo_redo(ns, marks[1], 0, 2, 0, 2)
+    check_undo_redo(ns, marks[2], 0, 3, 0, 7)
+    check_undo_redo(ns, marks[3], 0, 6, 0, 7)
+    check_undo_redo(ns, marks[4], 0, 7, 0, 7)
+    check_undo_redo(ns, marks[5], 0, 8, 0, 8)
+  end)
+
+  it('using <c-a> when negative and decrease in order of magnitude', function()
+    feed('ddiabc-1000xxx<esc>T-')
+    set_extmark(ns, marks[1], 0, 2)
+    set_extmark(ns, marks[2], 0, 3)
+    set_extmark(ns, marks[3], 0, 7)
+    set_extmark(ns, marks[4], 0, 8)
+    set_extmark(ns, marks[5], 0, 9)
+    feed('<c-a>')
+    check_undo_redo(ns, marks[1], 0, 2, 0, 2)
+    check_undo_redo(ns, marks[2], 0, 3, 0, 7)
+    check_undo_redo(ns, marks[3], 0, 7, 0, 7)
+    check_undo_redo(ns, marks[4], 0, 8, 0, 7)
+    check_undo_redo(ns, marks[5], 0, 9, 0, 8)
+  end)
+
+  it('using <c-x> without decrease in order of magnitude', function()
+    -- do_addsub in ops.c
+    feed('ddiabc999xxx<esc>Tc')
+    set_extmark(ns, marks[1], 0, 2)
+    set_extmark(ns, marks[2], 0, 3)
+    set_extmark(ns, marks[3], 0, 5)
+    set_extmark(ns, marks[4], 0, 6)
+    set_extmark(ns, marks[5], 0, 7)
+    feed('<c-x>')
+    check_undo_redo(ns, marks[1], 0, 2, 0, 2)
+    check_undo_redo(ns, marks[2], 0, 3, 0, 6)
+    check_undo_redo(ns, marks[3], 0, 5, 0, 6)
+    check_undo_redo(ns, marks[4], 0, 6, 0, 6)
+    check_undo_redo(ns, marks[5], 0, 7, 0, 7)
+  end)
+
+  it('using <c-x> when decrease in order of magnitude', function()
+    -- do_addsub in ops.c
+    feed('ddiabc1000xxx<esc>Tc')
+    set_extmark(ns, marks[1], 0, 2)
+    set_extmark(ns, marks[2], 0, 3)
+    set_extmark(ns, marks[3], 0, 6)
+    set_extmark(ns, marks[4], 0, 7)
+    set_extmark(ns, marks[5], 0, 8)
+    feed('<c-x>')
+    check_undo_redo(ns, marks[1], 0, 2, 0, 2)
+    check_undo_redo(ns, marks[2], 0, 3, 0, 6)
+    check_undo_redo(ns, marks[3], 0, 6, 0, 6)
+    check_undo_redo(ns, marks[4], 0, 7, 0, 6)
+    check_undo_redo(ns, marks[5], 0, 8, 0, 7)
+  end)
+
+  it('using <c-x> when negative and without increase in order of magnitude', function()
+    feed('ddiabc-998xxx<esc>T-')
+    set_extmark(ns, marks[1], 0, 2)
+    set_extmark(ns, marks[2], 0, 3)
+    set_extmark(ns, marks[3], 0, 6)
+    set_extmark(ns, marks[4], 0, 7)
+    set_extmark(ns, marks[5], 0, 8)
+    feed('<c-x>')
+    check_undo_redo(ns, marks[1], 0, 2, 0, 2)
+    check_undo_redo(ns, marks[2], 0, 3, 0, 7)
+    check_undo_redo(ns, marks[3], 0, 6, 0, 7)
+    check_undo_redo(ns, marks[4], 0, 7, 0, 7)
+    check_undo_redo(ns, marks[5], 0, 8, 0, 8)
+  end)
+
+  it('using <c-x> when negative and increase in order of magnitude', function()
+    feed('ddiabc-999xxx<esc>T-')
+    set_extmark(ns, marks[1], 0, 2)
+    set_extmark(ns, marks[2], 0, 3)
+    set_extmark(ns, marks[3], 0, 6)
+    set_extmark(ns, marks[4], 0, 7)
+    set_extmark(ns, marks[5], 0, 8)
+    feed('<c-x>')
+    check_undo_redo(ns, marks[1], 0, 2, 0, 2)
+    check_undo_redo(ns, marks[2], 0, 3, 0, 8)
+    check_undo_redo(ns, marks[3], 0, 6, 0, 8)
+    check_undo_redo(ns, marks[4], 0, 7, 0, 8)
+    check_undo_redo(ns, marks[5], 0, 8, 0, 9)
+  end)
+
+  it('throws consistent error codes', function()
+    local ns_invalid = ns2 + 1
+    eq("Invalid ns_id", pcall_err(set_extmark, ns_invalid, marks[1], positions[1][1], positions[1][2]))
+    eq("Invalid ns_id", pcall_err(curbufmeths.del_extmark, ns_invalid, marks[1]))
+    eq("Invalid ns_id", pcall_err(get_extmarks, ns_invalid, positions[1], positions[2]))
+    eq("Invalid ns_id", pcall_err(curbufmeths.get_extmark_by_id, ns_invalid, marks[1]))
+  end)
+
+  it('when col = line-length, set the mark on eol', function()
+    set_extmark(ns, marks[1], 0, -1)
+    local rv = curbufmeths.get_extmark_by_id(ns, marks[1])
+    eq({0, init_text:len()}, rv)
+    -- Test another
+    set_extmark(ns, marks[1], 0, -1)
+    rv = curbufmeths.get_extmark_by_id(ns, marks[1])
+    eq({0, init_text:len()}, rv)
+  end)
+
+  it('when col = line-length, set the mark on eol', function()
+    local invalid_col = init_text:len() + 1
+    eq("col value outside range", pcall_err(set_extmark, ns, marks[1], 0, invalid_col))
+  end)
+
+  it('fails when line > line_count', function()
+    local invalid_col = init_text:len() + 1
+    local invalid_lnum = 3
+    eq('line value outside range', pcall_err(set_extmark, ns, marks[1], invalid_lnum, invalid_col))
+    eq({}, curbufmeths.get_extmark_by_id(ns, marks[1]))
+  end)
+
+  it('bug from check_col in extmark_set', function()
+    -- This bug was caused by extmark_set always using check_col. check_col
+    -- always uses the current buffer. This wasn't working during undo so we
+    -- now use check_col and check_lnum only when they are required.
+    feed('A<cr>67890<cr>xx<esc>')
+    feed('A<cr>12345<cr>67890<cr>xx<esc>')
+    set_extmark(ns, marks[1], 3, 4)
+    feed([[:1,5s:5\n:5 <cr>]])
+    check_undo_redo(ns, marks[1], 3, 4, 2, 6)
+  end)
+
+  it('in read-only buffer', function()
+    command("view! runtime/doc/help.txt")
+    eq(true, curbufmeths.get_option('ro'))
+    local id = set_extmark(ns, 0, 0, 2)
+    eq({{id, 0, 2}}, get_extmarks(ns,0, -1))
+  end)
+
+  it('can set a mark to other buffer', function()
+    local buf = request('nvim_create_buf', 0, 1)
+    request('nvim_buf_set_lines', buf, 0, -1, 1, {"", ""})
+    local id = bufmeths.set_extmark(buf, ns, 0, 1, 0, {})
+    eq({{id, 1, 0}}, bufmeths.get_extmarks(buf, ns, 0, -1, {}))
+  end)
+
+  it('does not crash with append/delete/undo seqence', function()
+     meths.exec([[
+      let ns = nvim_create_namespace('myplugin')
+      call nvim_buf_set_extmark(0, ns, 0, 0, 0, {})
+      call append(0, '')
+      %delete
+      undo]],false)
+    eq(2, meths.eval('1+1')) -- did not crash
+  end)
+end)
+
+describe('Extmarks buffer api with many marks', function()
+  local ns1
+  local ns2
+  local ns_marks = {}
+  before_each(function()
+    clear()
+    ns1 = request('nvim_create_namespace', "ns1")
+    ns2 = request('nvim_create_namespace', "ns2")
+    ns_marks = {[ns1]={}, [ns2]={}}
+    local lines = {}
+    for i = 1,30 do
+      lines[#lines+1] = string.rep("x ",i)
+    end
+    curbufmeths.set_lines(0, -1, true, lines)
+    local ns = ns1
+    local q = 0
+    for i = 0,29 do
+      for j = 0,i do
+        local id = set_extmark(ns,0, i,j)
+        eq(nil, ns_marks[ns][id])
+        ok(id > 0)
+        ns_marks[ns][id] = {i,j}
+        ns = ns1+ns2-ns
+        q = q + 1
+      end
+    end
+    eq(233, #ns_marks[ns1])
+    eq(232, #ns_marks[ns2])
+
+  end)
+
+  local function get_marks(ns)
+    local mark_list = get_extmarks(ns, 0, -1)
+    local marks = {}
+    for _, mark in ipairs(mark_list) do
+      local id, row, col = unpack(mark)
+      eq(nil, marks[id], "duplicate mark")
+      marks[id] = {row,col}
+    end
+    return marks
+  end
+
+  it("can get marks", function()
+    eq(ns_marks[ns1], get_marks(ns1))
+    eq(ns_marks[ns2], get_marks(ns2))
+  end)
+
+  it("can clear all marks in ns", function()
+    curbufmeths.clear_namespace(ns1, 0, -1)
+    eq({}, get_marks(ns1))
+    eq(ns_marks[ns2], get_marks(ns2))
+    curbufmeths.clear_namespace(ns2, 0, -1)
+    eq({}, get_marks(ns1))
+    eq({}, get_marks(ns2))
+  end)
+
+  it("can clear line range", function()
+    curbufmeths.clear_namespace(ns1, 10, 20)
+    for id, mark in pairs(ns_marks[ns1]) do
+      if 10 <= mark[1] and mark[1] < 20 then
+        ns_marks[ns1][id] = nil
+      end
+    end
+    eq(ns_marks[ns1], get_marks(ns1))
+    eq(ns_marks[ns2], get_marks(ns2))
+  end)
+
+  it("can delete line", function()
+    feed('10Gdd')
+    for _, marks in pairs(ns_marks) do
+      for id, mark in pairs(marks) do
+        if mark[1] == 9 then
+          marks[id] = {9,0}
+        elseif mark[1] >= 10 then
+          mark[1] = mark[1] - 1
+        end
+      end
+    end
+    eq(ns_marks[ns1], get_marks(ns1))
+    eq(ns_marks[ns2], get_marks(ns2))
+  end)
+
+  it("can delete lines", function()
+    feed('10G10dd')
+    for _, marks in pairs(ns_marks) do
+      for id, mark in pairs(marks) do
+        if 9 <= mark[1] and mark[1] < 19 then
+          marks[id] = {9,0}
+        elseif mark[1] >= 19 then
+          mark[1] = mark[1] - 10
+        end
+      end
+    end
+    eq(ns_marks[ns1], get_marks(ns1))
+    eq(ns_marks[ns2], get_marks(ns2))
+  end)
+
+  it("can wipe buffer", function()
+    command('bwipe!')
+    eq({}, get_marks(ns1))
+    eq({}, get_marks(ns2))
+  end)
+end)