Merge remote-tracking branch 'upstream/master' into mix_20240309

34 files changed, 2077 insertions, 681 deletions

diff --git a/test/functional/lua/api_spec.lua b/test/functional/lua/api_spec.lua
index acd56a0ddb..56969150bd 100644
--- a/test/functional/lua/api_spec.lua
+++ b/test/functional/lua/api_spec.lua
@@ -1,15 +1,16 @@
 -- Test suite for testing interactions with API bindings
-local helpers = require('test.functional.helpers')(after_each)
-
-local exc_exec = helpers.exc_exec
-local remove_trace = helpers.remove_trace
-local fn = helpers.fn
-local clear = helpers.clear
-local eval = helpers.eval
+local t = require('test.testutil')
+local n = require('test.functional.testnvim')()
+
+local exc_exec = n.exc_exec
+local remove_trace = t.remove_trace
+local fn = n.fn
+local clear = n.clear
+local eval = n.eval
 local NIL = vim.NIL
-local eq = helpers.eq
-local exec_lua = helpers.exec_lua
-local pcall_err = helpers.pcall_err
+local eq = t.eq
+local exec_lua = n.exec_lua
+local pcall_err = t.pcall_err
 
 before_each(clear)
 
diff --git a/test/functional/lua/base64_spec.lua b/test/functional/lua/base64_spec.lua
index 21fd536a98..529f5f56e8 100644
--- a/test/functional/lua/base64_spec.lua
+++ b/test/functional/lua/base64_spec.lua
@@ -1,9 +1,11 @@
-local helpers = require('test.functional.helpers')(after_each)
-local clear = helpers.clear
-local exec_lua = helpers.exec_lua
-local eq = helpers.eq
-local pcall_err = helpers.pcall_err
-local matches = helpers.matches
+local t = require('test.testutil')
+local n = require('test.functional.testnvim')()
+
+local clear = n.clear
+local exec_lua = n.exec_lua
+local eq = t.eq
+local pcall_err = t.pcall_err
+local matches = t.matches
 
 describe('vim.base64', function()
   before_each(clear)
@@ -42,6 +44,7 @@ describe('vim.base64', function()
         ̦H̬̤̗̤͝e͜ ̜̥̝̻͍̟́w̕h̖̯͓o̝͙̖͎̱̮ ҉̺̙̞̟͈W̷̼̭a̺̪͍į͈͕̭͙̯̜t̶̼̮s̘͙͖̕ ̠̫̠B̻͍͙͉̳ͅe̵h̵̬͇̫͙i̹͓̳̳̮͎̫̕n͟d̴̪̜̖ ̰͉̩͇͙̲͞ͅT͖̼͓̪͢h͏͓̮̻e̬̝̟ͅ ̤̹̝W͙̞̝͔͇͝ͅa͏͓͔̹̼̣l̴͔̰̤̟͔ḽ̫.͕
         Z̮̞̠͙͔ͅḀ̗̞͈̻̗Ḷ͙͎̯̹̞͓G̻O̭̗̮
       ]],
+      'Hello\0world',
     }
 
     for _, v in ipairs(values) do
diff --git a/test/functional/lua/buffer_updates_spec.lua b/test/functional/lua/buffer_updates_spec.lua
index 714e1b951f..d4af7e4732 100644
--- a/test/functional/lua/buffer_updates_spec.lua
+++ b/test/functional/lua/buffer_updates_spec.lua
@@ -1,17 +1,19 @@
 -- Test suite for testing interactions with API bindings
-local helpers = require('test.functional.helpers')(after_each)
-
-local command = helpers.command
-local api = helpers.api
-local fn = helpers.fn
-local clear = helpers.clear
-local eq = helpers.eq
-local fail = helpers.fail
-local exec_lua = helpers.exec_lua
-local feed = helpers.feed
-local expect_events = helpers.expect_events
-local write_file = helpers.write_file
-local dedent = helpers.dedent
+local t = require('test.testutil')
+local n = require('test.functional.testnvim')()
+local Screen = require('test.functional.ui.screen')
+
+local command = n.command
+local api = n.api
+local fn = n.fn
+local clear = n.clear
+local eq = t.eq
+local fail = t.fail
+local exec_lua = n.exec_lua
+local feed = n.feed
+local expect_events = t.expect_events
+local write_file = t.write_file
+local dedent = t.dedent
 
 local origlines = {
   'original line 1',
@@ -291,11 +293,11 @@ describe('lua buffer event callbacks: on_lines', function()
 
     exec_lua(code)
     command('q!')
-    helpers.assert_alive()
+    n.assert_alive()
 
     exec_lua(code)
     command('bd!')
-    helpers.assert_alive()
+    n.assert_alive()
   end)
 
   it('#12718 lnume', function()
@@ -312,31 +314,71 @@ describe('lua buffer event callbacks: on_lines', function()
     feed('G0')
     feed('p')
     -- Is the last arg old_byte_size correct? Doesn't matter for this PR
-    eq(api.nvim_get_var('linesev'), { 'lines', 1, 4, 2, 3, 5, 4 })
+    eq({ 'lines', 1, 4, 2, 3, 5, 4 }, api.nvim_get_var('linesev'))
 
     feed('2G0')
     feed('p')
-    eq(api.nvim_get_var('linesev'), { 'lines', 1, 5, 1, 4, 4, 8 })
+    eq({ 'lines', 1, 5, 1, 4, 4, 8 }, api.nvim_get_var('linesev'))
 
     feed('1G0')
     feed('P')
-    eq(api.nvim_get_var('linesev'), { 'lines', 1, 6, 0, 3, 3, 9 })
+    eq({ 'lines', 1, 6, 0, 3, 3, 9 }, api.nvim_get_var('linesev'))
   end)
 
-  it(
-    'calling nvim_buf_call() from callback does not cause Normal mode CTRL-A to misbehave #16729',
-    function()
-      exec_lua([[
+  it('nvim_buf_call() from callback does not cause wrong Normal mode CTRL-A #16729', function()
+    exec_lua([[
       vim.api.nvim_buf_attach(0, false, {
         on_lines = function(...)
           vim.api.nvim_buf_call(0, function() end)
         end,
       })
     ]])
-      feed('itest123<Esc><C-A>')
-      eq('test124', api.nvim_get_current_line())
-    end
-  )
+    feed('itest123<Esc><C-A>')
+    eq('test124', api.nvim_get_current_line())
+  end)
+
+  it('setting extmark in on_lines callback works', function()
+    local screen = Screen.new(40, 6)
+    screen:attach()
+
+    api.nvim_buf_set_lines(0, 0, -1, true, { 'aaa', 'bbb', 'ccc' })
+    exec_lua([[
+      local ns = vim.api.nvim_create_namespace('')
+      vim.api.nvim_buf_attach(0, false, {
+        on_lines = function(_, _, _, row, _, end_row)
+          vim.api.nvim_buf_clear_namespace(0, ns, row, end_row)
+          for i = row, end_row - 1 do
+            local id = vim.api.nvim_buf_set_extmark(0, ns, i, 0, {
+              virt_text = {{ 'NEW' .. tostring(i), 'WarningMsg' }},
+            })
+          end
+        end,
+      })
+    ]])
+
+    feed('o')
+    screen:expect({
+      grid = [[
+        aaa                                     |
+        ^ {19:NEW1}                                   |
+        bbb                                     |
+        ccc                                     |
+        {1:~                                       }|
+        {5:-- INSERT --}                            |
+      ]],
+    })
+    feed('<CR>')
+    screen:expect({
+      grid = [[
+        aaa                                     |
+         {19:NEW1}                                   |
+        ^ {19:NEW2}                                   |
+        bbb                                     |
+        ccc                                     |
+        {5:-- INSERT --}                            |
+      ]],
+    })
+  end)
 end)
 
 describe('lua: nvim_buf_attach on_bytes', function()
@@ -426,14 +468,14 @@ describe('lua: nvim_buf_attach on_bytes', function()
 
     it('opening lines', function()
       local check_events = setup_eventcheck(verify, origlines)
-      -- api.nvim_set_option_value('autoindent', true, {})
+      api.nvim_set_option_value('autoindent', false, {})
       feed 'Go'
       check_events {
         { 'test1', 'bytes', 1, 3, 7, 0, 114, 0, 0, 0, 1, 0, 1 },
       }
       feed '<cr>'
       check_events {
-        { 'test1', 'bytes', 1, 5, 7, 0, 114, 0, 0, 0, 1, 0, 1 },
+        { 'test1', 'bytes', 1, 4, 7, 0, 114, 0, 0, 0, 1, 0, 1 },
       }
     end)
 
@@ -447,7 +489,7 @@ describe('lua: nvim_buf_attach on_bytes', function()
       feed '<cr>'
       check_events {
         { 'test1', 'bytes', 1, 4, 7, 0, 114, 0, 4, 4, 0, 0, 0 },
-        { 'test1', 'bytes', 1, 5, 7, 0, 114, 0, 0, 0, 1, 4, 5 },
+        { 'test1', 'bytes', 1, 4, 7, 0, 114, 0, 0, 0, 1, 4, 5 },
       }
     end)
 
@@ -477,7 +519,7 @@ describe('lua: nvim_buf_attach on_bytes', function()
       api.nvim_set_option_value('filetype', 'c', {})
       feed 'A<CR>'
       check_events {
-        { 'test1', 'bytes', 1, 4, 0, 10, 10, 0, 0, 0, 1, 3, 4 },
+        { 'test1', 'bytes', 1, 3, 0, 10, 10, 0, 0, 0, 1, 3, 4 },
       }
 
       feed '<ESC>'
@@ -493,7 +535,7 @@ describe('lua: nvim_buf_attach on_bytes', function()
       feed '<CR>'
       check_events {
         { 'test1', 'bytes', 1, 6, 1, 2, 13, 0, 1, 1, 0, 0, 0 },
-        { 'test1', 'bytes', 1, 7, 1, 2, 13, 0, 0, 0, 1, 3, 4 },
+        { 'test1', 'bytes', 1, 6, 1, 2, 13, 0, 0, 0, 1, 3, 4 },
       }
     end)
 
@@ -541,7 +583,7 @@ describe('lua: nvim_buf_attach on_bytes', function()
 
       feed 'cc'
       check_events {
-        { 'test1', 'bytes', 1, 4, 0, 0, 0, 0, 15, 15, 0, 0, 0 },
+        { 'test1', 'bytes', 1, 3, 0, 0, 0, 0, 15, 15, 0, 0, 0 },
       }
 
       feed '<ESC>'
@@ -924,7 +966,7 @@ describe('lua: nvim_buf_attach on_bytes', function()
       command('e! Xtest-undofile')
       command('set undodir=. | set undofile')
 
-      local ns = helpers.request('nvim_create_namespace', 'ns1')
+      local ns = n.request('nvim_create_namespace', 'ns1')
       api.nvim_buf_set_extmark(0, ns, 0, 0, {})
 
       eq({ '12345', 'hello world' }, api.nvim_buf_get_lines(0, 0, -1, true))
@@ -1225,6 +1267,25 @@ describe('lua: nvim_buf_attach on_bytes', function()
       }
     end)
 
+    it('prompt buffer', function()
+      local check_events = setup_eventcheck(verify, {})
+      api.nvim_set_option_value('buftype', 'prompt', {})
+      feed('i')
+      check_events {
+        { 'test1', 'bytes', 1, 3, 0, 0, 0, 0, 0, 0, 0, 2, 2 },
+      }
+      feed('<CR>')
+      check_events {
+        { 'test1', 'bytes', 1, 4, 1, 0, 3, 0, 0, 0, 1, 0, 1 },
+        { 'test1', 'bytes', 1, 5, 1, 0, 3, 0, 0, 0, 0, 2, 2 },
+      }
+      feed('<CR>')
+      check_events {
+        { 'test1', 'bytes', 1, 6, 2, 0, 6, 0, 0, 0, 1, 0, 1 },
+        { 'test1', 'bytes', 1, 7, 2, 0, 6, 0, 0, 0, 0, 2, 2 },
+      }
+    end)
+
     local function test_lockmarks(mode)
       local description = (mode ~= '') and mode or '(baseline)'
       it('test_lockmarks ' .. description .. ' %delete _', function()
diff --git a/test/functional/lua/command_line_completion_spec.lua b/test/functional/lua/command_line_completion_spec.lua
index b88a38082f..2ba432133b 100644
--- a/test/functional/lua/command_line_completion_spec.lua
+++ b/test/functional/lua/command_line_completion_spec.lua
@@ -1,8 +1,9 @@
-local helpers = require('test.functional.helpers')(after_each)
+local t = require('test.testutil')
+local n = require('test.functional.testnvim')()
 
-local clear = helpers.clear
-local eq = helpers.eq
-local exec_lua = helpers.exec_lua
+local clear = n.clear
+local eq = t.eq
+local exec_lua = n.exec_lua
 
 local get_completions = function(input, env)
   return exec_lua('return {vim._expand_pat(...)}', input, env)
diff --git a/test/functional/lua/commands_spec.lua b/test/functional/lua/commands_spec.lua
index b8d0638ce5..57b084d3d6 100644
--- a/test/functional/lua/commands_spec.lua
+++ b/test/functional/lua/commands_spec.lua
@@ -1,24 +1,25 @@
 -- Test suite for checking :lua* commands
-local helpers = require('test.functional.helpers')(after_each)
+local t = require('test.testutil')
+local n = require('test.functional.testnvim')()
 local Screen = require('test.functional.ui.screen')
 
-local eq = helpers.eq
+local eq = t.eq
 local NIL = vim.NIL
-local eval = helpers.eval
-local feed = helpers.feed
-local clear = helpers.clear
-local matches = helpers.matches
-local api = helpers.api
-local exec_lua = helpers.exec_lua
-local exec_capture = helpers.exec_capture
-local fn = helpers.fn
-local source = helpers.source
-local dedent = helpers.dedent
-local command = helpers.command
-local exc_exec = helpers.exc_exec
-local pcall_err = helpers.pcall_err
-local write_file = helpers.write_file
-local remove_trace = helpers.remove_trace
+local eval = n.eval
+local feed = n.feed
+local clear = n.clear
+local matches = t.matches
+local api = n.api
+local exec_lua = n.exec_lua
+local exec_capture = n.exec_capture
+local fn = n.fn
+local source = n.source
+local dedent = t.dedent
+local command = n.command
+local exc_exec = n.exc_exec
+local pcall_err = t.pcall_err
+local write_file = t.write_file
+local remove_trace = t.remove_trace
 
 before_each(clear)
 
diff --git a/test/functional/lua/comment_spec.lua b/test/functional/lua/comment_spec.lua
new file mode 100644
index 0000000000..bbf061a2ab
--- /dev/null
+++ b/test/functional/lua/comment_spec.lua
@@ -0,0 +1,651 @@
+local t = require('test.testutil')
+local n = require('test.functional.testnvim')()
+
+local api = n.api
+local clear = n.clear
+local eq = t.eq
+local exec_capture = n.exec_capture
+local exec_lua = n.exec_lua
+local feed = n.feed
+
+-- Reference text
+-- aa
+--  aa
+--   aa
+--
+--   aa
+--  aa
+-- aa
+local example_lines = { 'aa', ' aa', '  aa', '', '  aa', ' aa', 'aa' }
+
+local set_commentstring = function(commentstring)
+  api.nvim_set_option_value('commentstring', commentstring, { buf = 0 })
+end
+
+local get_lines = function(from, to)
+  from, to = from or 0, to or -1
+  return api.nvim_buf_get_lines(0, from, to, false)
+end
+
+local set_lines = function(lines, from, to)
+  from, to = from or 0, to or -1
+  api.nvim_buf_set_lines(0, from, to, false, lines)
+end
+
+local set_cursor = function(row, col)
+  api.nvim_win_set_cursor(0, { row, col })
+end
+
+local get_cursor = function()
+  return api.nvim_win_get_cursor(0)
+end
+
+local setup_treesitter = function()
+  -- NOTE: This leverages bundled Vimscript and Lua tree-sitter parsers
+  api.nvim_set_option_value('filetype', 'vim', { buf = 0 })
+  exec_lua('vim.treesitter.start()')
+end
+
+before_each(function()
+  clear({ args_rm = { '--cmd' }, args = { '--clean' } })
+end)
+
+describe('commenting', function()
+  before_each(function()
+    set_lines(example_lines)
+    set_commentstring('# %s')
+  end)
+
+  describe('toggle_lines()', function()
+    local toggle_lines = function(...)
+      exec_lua('require("vim._comment").toggle_lines(...)', ...)
+    end
+
+    it('works', function()
+      toggle_lines(3, 5)
+      eq(get_lines(2, 5), { '  # aa', '  #', '  # aa' })
+
+      toggle_lines(3, 5)
+      eq(get_lines(2, 5), { '  aa', '', '  aa' })
+    end)
+
+    it("works with different 'commentstring' options", function()
+      local validate = function(lines_before, lines_after, lines_again)
+        set_lines(lines_before)
+        toggle_lines(1, #lines_before)
+        eq(get_lines(), lines_after)
+        toggle_lines(1, #lines_before)
+        eq(get_lines(), lines_again or lines_before)
+      end
+
+      -- Single whitespace inside comment parts (main case)
+      set_commentstring('# %s #')
+      -- - General case
+      validate(
+        { 'aa', '  aa', 'aa  ', '  aa  ' },
+        { '# aa #', '#   aa #', '# aa   #', '#   aa   #' }
+      )
+      -- - Tabs
+      validate(
+        { 'aa', '\taa', 'aa\t', '\taa\t' },
+        { '# aa #', '# \taa #', '# aa\t #', '# \taa\t #' }
+      )
+      -- - With indent
+      validate({ ' aa', '  aa' }, { ' # aa #', ' #  aa #' })
+      -- - With blank/empty lines
+      validate(
+        { '  aa', '', '  ', '\t' },
+        { '  # aa #', '  ##', '  ##', '  ##' },
+        { '  aa', '', '', '' }
+      )
+
+      set_commentstring('# %s')
+      validate({ 'aa', '  aa', 'aa  ', '  aa  ' }, { '# aa', '#   aa', '# aa  ', '#   aa  ' })
+      validate({ 'aa', '\taa', 'aa\t', '\taa\t' }, { '# aa', '# \taa', '# aa\t', '# \taa\t' })
+      validate({ ' aa', '  aa' }, { ' # aa', ' #  aa' })
+      validate(
+        { '  aa', '', '  ', '\t' },
+        { '  # aa', '  #', '  #', '  #' },
+        { '  aa', '', '', '' }
+      )
+
+      set_commentstring('%s #')
+      validate({ 'aa', '  aa', 'aa  ', '  aa  ' }, { 'aa #', '  aa #', 'aa   #', '  aa   #' })
+      validate({ 'aa', '\taa', 'aa\t', '\taa\t' }, { 'aa #', '\taa #', 'aa\t #', '\taa\t #' })
+      validate({ ' aa', '  aa' }, { ' aa #', '  aa #' })
+      validate(
+        { '  aa', '', '  ', '\t' },
+        { '  aa #', '  #', '  #', '  #' },
+        { '  aa', '', '', '' }
+      )
+
+      -- No whitespace in parts
+      set_commentstring('#%s#')
+      validate({ 'aa', '  aa', 'aa  ', '  aa  ' }, { '#aa#', '#  aa#', '#aa  #', '#  aa  #' })
+      validate({ 'aa', '\taa', 'aa\t', '\taa\t' }, { '#aa#', '#\taa#', '#aa\t#', '#\taa\t#' })
+      validate({ ' aa', '  aa' }, { ' #aa#', ' # aa#' })
+      validate(
+        { '  aa', '', '  ', '\t' },
+        { '  #aa#', '  ##', '  ##', '  ##' },
+        { '  aa', '', '', '' }
+      )
+
+      set_commentstring('#%s')
+      validate({ 'aa', '  aa', 'aa  ', '  aa  ' }, { '#aa', '#  aa', '#aa  ', '#  aa  ' })
+      validate({ 'aa', '\taa', 'aa\t', '\taa\t' }, { '#aa', '#\taa', '#aa\t', '#\taa\t' })
+      validate({ ' aa', '  aa' }, { ' #aa', ' # aa' })
+      validate({ '  aa', '', '  ', '\t' }, { '  #aa', '  #', '  #', '  #' }, { '  aa', '', '', '' })
+
+      set_commentstring('%s#')
+      validate({ 'aa', '  aa', 'aa  ', '  aa  ' }, { 'aa#', '  aa#', 'aa  #', '  aa  #' })
+      validate({ 'aa', '\taa', 'aa\t', '\taa\t' }, { 'aa#', '\taa#', 'aa\t#', '\taa\t#' })
+      validate({ ' aa', '  aa' }, { ' aa#', '  aa#' })
+      validate({ '  aa', '', '  ', '\t' }, { '  aa#', '  #', '  #', '  #' }, { '  aa', '', '', '' })
+
+      -- Extra whitespace inside comment parts
+      set_commentstring('#  %s  #')
+      validate(
+        { 'aa', '  aa', 'aa  ', '  aa  ' },
+        { '#  aa  #', '#    aa  #', '#  aa    #', '#    aa    #' }
+      )
+      validate(
+        { 'aa', '\taa', 'aa\t', '\taa\t' },
+        { '#  aa  #', '#  \taa  #', '#  aa\t  #', '#  \taa\t  #' }
+      )
+      validate({ ' aa', '  aa' }, { ' #  aa  #', ' #   aa  #' })
+      validate(
+        { '  aa', '', '  ', '\t' },
+        { '  #  aa  #', '  ##', '  ##', '  ##' },
+        { '  aa', '', '', '' }
+      )
+
+      set_commentstring('#  %s')
+      validate({ 'aa', '  aa', 'aa  ', '  aa  ' }, { '#  aa', '#    aa', '#  aa  ', '#    aa  ' })
+      validate({ 'aa', '\taa', 'aa\t', '\taa\t' }, { '#  aa', '#  \taa', '#  aa\t', '#  \taa\t' })
+      validate({ ' aa', '  aa' }, { ' #  aa', ' #   aa' })
+      validate(
+        { '  aa', '', '  ', '\t' },
+        { '  #  aa', '  #', '  #', '  #' },
+        { '  aa', '', '', '' }
+      )
+
+      set_commentstring('%s  #')
+      validate({ 'aa', '  aa', 'aa  ', '  aa  ' }, { 'aa  #', '  aa  #', 'aa    #', '  aa    #' })
+      validate({ 'aa', '\taa', 'aa\t', '\taa\t' }, { 'aa  #', '\taa  #', 'aa\t  #', '\taa\t  #' })
+      validate({ ' aa', '  aa' }, { ' aa  #', '  aa  #' })
+      validate(
+        { '  aa', '', '  ', '\t' },
+        { '  aa  #', '  #', '  #', '  #' },
+        { '  aa', '', '', '' }
+      )
+
+      -- Whitespace outside of comment parts
+      set_commentstring(' # %s # ')
+      validate(
+        { 'aa', '  aa', 'aa  ', '  aa  ' },
+        { ' # aa # ', ' #   aa # ', ' # aa   # ', ' #   aa   # ' }
+      )
+      validate(
+        { 'aa', '\taa', 'aa\t', '\taa\t' },
+        { ' # aa # ', ' # \taa # ', ' # aa\t # ', ' # \taa\t # ' }
+      )
+      validate({ ' aa', '  aa' }, { '  # aa # ', '  #  aa # ' })
+      validate(
+        { '  aa', '', '  ', '\t' },
+        { '   # aa # ', '  ##', '  ##', '  ##' },
+        { '  aa', '', '', '' }
+      )
+
+      set_commentstring(' # %s ')
+      validate(
+        { 'aa', '  aa', 'aa  ', '  aa  ' },
+        { ' # aa ', ' #   aa ', ' # aa   ', ' #   aa   ' }
+      )
+      validate(
+        { 'aa', '\taa', 'aa\t', '\taa\t' },
+        { ' # aa ', ' # \taa ', ' # aa\t ', ' # \taa\t ' }
+      )
+      validate({ ' aa', '  aa' }, { '  # aa ', '  #  aa ' })
+      validate(
+        { '  aa', '', '  ', '\t' },
+        { '   # aa ', '  #', '  #', '  #' },
+        { '  aa', '', '', '' }
+      )
+
+      set_commentstring(' %s # ')
+      validate(
+        { 'aa', '  aa', 'aa  ', '  aa  ' },
+        { ' aa # ', '   aa # ', ' aa   # ', '   aa   # ' }
+      )
+      validate(
+        { 'aa', '\taa', 'aa\t', '\taa\t' },
+        { ' aa # ', ' \taa # ', ' aa\t # ', ' \taa\t # ' }
+      )
+      validate({ ' aa', '  aa' }, { '  aa # ', '   aa # ' })
+      validate(
+        { '  aa', '', '  ', '\t' },
+        { '   aa # ', '  #', '  #', '  #' },
+        { '  aa', '', '', '' }
+      )
+
+      -- LaTeX
+      set_commentstring('% %s')
+      validate({ 'aa', '  aa', 'aa  ', '  aa  ' }, { '% aa', '%   aa', '% aa  ', '%   aa  ' })
+      validate({ 'aa', '\taa', 'aa\t', '\taa\t' }, { '% aa', '% \taa', '% aa\t', '% \taa\t' })
+      validate({ ' aa', '  aa' }, { ' % aa', ' %  aa' })
+      validate(
+        { '  aa', '', '  ', '\t' },
+        { '  % aa', '  %', '  %', '  %' },
+        { '  aa', '', '', '' }
+      )
+    end)
+
+    it('respects tree-sitter injections', function()
+      setup_treesitter()
+
+      local lines = {
+        'set background=dark',
+        'lua << EOF',
+        'print(1)',
+        'vim.api.nvim_exec2([[',
+        '    set background=light',
+        ']])',
+        'EOF',
+      }
+
+      -- Single line comments
+      local validate = function(line, ref_output)
+        set_lines(lines)
+        toggle_lines(line, line)
+        eq(get_lines(line - 1, line)[1], ref_output)
+      end
+
+      validate(1, '"set background=dark')
+      validate(2, '"lua << EOF')
+      validate(3, '-- print(1)')
+      validate(4, '-- vim.api.nvim_exec2([[')
+      validate(5, '    "set background=light')
+      validate(6, '-- ]])')
+      validate(7, '"EOF')
+
+      -- Multiline comments should be computed based on first line 'commentstring'
+      set_lines(lines)
+      toggle_lines(1, 3)
+      local out_lines = get_lines()
+      eq(out_lines[1], '"set background=dark')
+      eq(out_lines[2], '"lua << EOF')
+      eq(out_lines[3], '"print(1)')
+    end)
+
+    it('correctly computes indent', function()
+      toggle_lines(2, 4)
+      eq(get_lines(1, 4), { ' # aa', ' #  aa', ' #' })
+    end)
+
+    it('correctly detects comment/uncomment', function()
+      local validate = function(from, to, ref_lines)
+        set_lines({ '', 'aa', '# aa', '# aa', 'aa', '' })
+        toggle_lines(from, to)
+        eq(get_lines(), ref_lines)
+      end
+
+      -- It should uncomment only if all non-blank lines are comments
+      validate(3, 4, { '', 'aa', 'aa', 'aa', 'aa', '' })
+      validate(2, 4, { '', '# aa', '# # aa', '# # aa', 'aa', '' })
+      validate(3, 5, { '', 'aa', '# # aa', '# # aa', '# aa', '' })
+      validate(1, 6, { '#', '# aa', '# # aa', '# # aa', '# aa', '#' })
+
+      -- Blank lines should be ignored when making a decision
+      set_lines({ '# aa', '', '  ', '\t', '# aa' })
+      toggle_lines(1, 5)
+      eq(get_lines(), { 'aa', '', '  ', '\t', 'aa' })
+    end)
+
+    it('correctly matches comment parts during checking and uncommenting', function()
+      local validate = function(from, to, ref_lines)
+        set_lines({ '/*aa*/', '/* aa */', '/*  aa  */' })
+        toggle_lines(from, to)
+        eq(get_lines(), ref_lines)
+      end
+
+      -- Should first try to match 'commentstring' parts exactly with their
+      -- whitespace, with fallback on trimmed parts
+      set_commentstring('/*%s*/')
+      validate(1, 3, { 'aa', ' aa ', '  aa  ' })
+      validate(2, 3, { '/*aa*/', ' aa ', '  aa  ' })
+      validate(3, 3, { '/*aa*/', '/* aa */', '  aa  ' })
+
+      set_commentstring('/* %s */')
+      validate(1, 3, { 'aa', 'aa', ' aa ' })
+      validate(2, 3, { '/*aa*/', 'aa', ' aa ' })
+      validate(3, 3, { '/*aa*/', '/* aa */', ' aa ' })
+
+      set_commentstring('/*  %s  */')
+      validate(1, 3, { 'aa', ' aa ', 'aa' })
+      validate(2, 3, { '/*aa*/', ' aa ', 'aa' })
+      validate(3, 3, { '/*aa*/', '/* aa */', 'aa' })
+
+      set_commentstring(' /*%s*/ ')
+      validate(1, 3, { 'aa', ' aa ', '  aa  ' })
+      validate(2, 3, { '/*aa*/', ' aa ', '  aa  ' })
+      validate(3, 3, { '/*aa*/', '/* aa */', '  aa  ' })
+    end)
+
+    it('uncomments on inconsistent indent levels', function()
+      set_lines({ '# aa', ' # aa', '  # aa' })
+      toggle_lines(1, 3)
+      eq(get_lines(), { 'aa', ' aa', '  aa' })
+    end)
+
+    it('respects tabs', function()
+      api.nvim_set_option_value('expandtab', false, { buf = 0 })
+      set_lines({ '\t\taa', '\t\taa' })
+
+      toggle_lines(1, 2)
+      eq(get_lines(), { '\t\t# aa', '\t\t# aa' })
+
+      toggle_lines(1, 2)
+      eq(get_lines(), { '\t\taa', '\t\taa' })
+    end)
+
+    it('works with trailing whitespace', function()
+      -- Without right-hand side
+      set_commentstring('# %s')
+      set_lines({ ' aa', ' aa  ', '  ' })
+      toggle_lines(1, 3)
+      eq(get_lines(), { ' # aa', ' # aa  ', ' #' })
+      toggle_lines(1, 3)
+      eq(get_lines(), { ' aa', ' aa  ', '' })
+
+      -- With right-hand side
+      set_commentstring('%s #')
+      set_lines({ ' aa', ' aa  ', '  ' })
+      toggle_lines(1, 3)
+      eq(get_lines(), { ' aa #', ' aa   #', ' #' })
+      toggle_lines(1, 3)
+      eq(get_lines(), { ' aa', ' aa  ', '' })
+
+      -- Trailing whitespace after right side should be preserved for non-blanks
+      set_commentstring('%s #')
+      set_lines({ ' aa #  ', ' aa #\t', ' #  ', ' #\t' })
+      toggle_lines(1, 4)
+      eq(get_lines(), { ' aa  ', ' aa\t', '', '' })
+    end)
+  end)
+
+  describe('Operator', function()
+    it('works in Normal mode', function()
+      set_cursor(2, 2)
+      feed('gc', 'ap')
+      eq(get_lines(), { '# aa', '#  aa', '#   aa', '#', '  aa', ' aa', 'aa' })
+      -- Cursor moves to start line
+      eq(get_cursor(), { 1, 0 })
+
+      -- Supports `v:count`
+      set_lines(example_lines)
+      set_cursor(2, 0)
+      feed('2gc', 'ap')
+      eq(get_lines(), { '# aa', '#  aa', '#   aa', '#', '#   aa', '#  aa', '# aa' })
+    end)
+
+    it('allows dot-repeat in Normal mode', function(