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

16 files changed, 1952 insertions, 490 deletions

diff --git a/test/functional/api/autocmd_spec.lua b/test/functional/api/autocmd_spec.lua
index e89abf6c64..3f9883f43f 100644
--- a/test/functional/api/autocmd_spec.lua
+++ b/test/functional/api/autocmd_spec.lua
@@ -1,14 +1,15 @@
-local helpers = require('test.functional.helpers')(after_each)
-
-local clear = helpers.clear
-local command = helpers.command
-local eq = helpers.eq
-local neq = helpers.neq
-local exec_lua = helpers.exec_lua
-local matches = helpers.matches
-local api = helpers.api
-local source = helpers.source
-local pcall_err = helpers.pcall_err
+local t = require('test.testutil')
+local n = require('test.functional.testnvim')()
+
+local clear = n.clear
+local command = n.command
+local eq = t.eq
+local neq = t.neq
+local exec_lua = n.exec_lua
+local matches = t.matches
+local api = n.api
+local source = n.source
+local pcall_err = t.pcall_err
 
 before_each(clear)
 
@@ -355,6 +356,44 @@ describe('autocmd api', function()
       test({ 'list' })
       test({ foo = 'bar' })
     end)
+
+    it('function in arbitrary data is passed to all autocmds #28353', function()
+      eq(
+        1303,
+        exec_lua([[
+          local res = 1
+
+          local fun = function(m, x)
+            res = res * m + x
+          end
+
+          local group = vim.api.nvim_create_augroup('MyTest', { clear = false })
+
+          vim.api.nvim_create_autocmd('User', {
+            group = group,
+            callback = function(payload)
+              payload.data.fun(10, payload.data.x)
+            end,
+            pattern = 'MyEvent',
+          })
+          vim.api.nvim_create_autocmd('User', {
+            group = group,
+            callback = function(payload)
+              payload.data.fun(100, payload.data.x)
+            end,
+            pattern = 'MyEvent',
+          })
+
+          vim.api.nvim_exec_autocmds('User', {
+            group = group,
+            pattern = 'MyEvent',
+            data = { x = 3, fun = fun },
+          })
+
+          return res
+        ]])
+      )
+    end)
   end)
 
   describe('nvim_get_autocmds', function()
@@ -610,15 +649,17 @@ describe('autocmd api', function()
       it('can retrieve a callback from an autocmd', function()
         local content = 'I Am A Callback'
         api.nvim_set_var('content', content)
-
-        local result = exec_lua([[
+        exec_lua([[
           local cb = function() return vim.g.content end
           vim.api.nvim_create_autocmd("User", {
             pattern = "TestTrigger",
             desc = "A test autocommand with a callback",
             callback = cb,
           })
-          local aus = vim.api.nvim_get_autocmds({ event = 'User', pattern = 'TestTrigger'})
+        ]])
+
+        local result = exec_lua([[
+          local aus = vim.api.nvim_get_autocmds({ event = 'User', pattern = 'TestTrigger' })
           local first = aus[1]
           return {
             cb = {
@@ -627,9 +668,14 @@ describe('autocmd api', function()
             }
           }
         ]])
+        eq({ cb = { type = 'function', can_retrieve = true } }, result)
 
-        eq('function', result.cb.type)
-        eq(true, result.cb.can_retrieve)
+        -- Also test with Vimscript
+        source([[
+          let s:aus = nvim_get_autocmds({'event': 'User', 'pattern': 'TestTrigger'})
+          let g:result = s:aus[0].callback()
+        ]])
+        eq(content, api.nvim_get_var('result'))
       end)
 
       it(
diff --git a/test/functional/api/buffer_spec.lua b/test/functional/api/buffer_spec.lua
index 78d220ff57..cf69958fd8 100644
--- a/test/functional/api/buffer_spec.lua
+++ b/test/functional/api/buffer_spec.lua
@@ -1,21 +1,23 @@
-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 clear = helpers.clear
-local eq = helpers.eq
-local ok = helpers.ok
-local describe_lua_and_rpc = helpers.describe_lua_and_rpc(describe)
-local api = helpers.api
-local fn = helpers.fn
-local request = helpers.request
-local exc_exec = helpers.exc_exec
-local exec_lua = helpers.exec_lua
-local feed_command = helpers.feed_command
-local insert = helpers.insert
+
+local clear = n.clear
+local eq = t.eq
+local ok = t.ok
+local describe_lua_and_rpc = n.describe_lua_and_rpc(describe)
+local api = n.api
+local fn = n.fn
+local request = n.request
+local exc_exec = n.exc_exec
+local exec_lua = n.exec_lua
+local feed_command = n.feed_command
+local insert = n.insert
 local NIL = vim.NIL
-local command = helpers.command
-local feed = helpers.feed
-local pcall_err = helpers.pcall_err
-local assert_alive = helpers.assert_alive
+local command = n.command
+local feed = n.feed
+local pcall_err = t.pcall_err
+local assert_alive = n.assert_alive
 
 describe('api/buf', function()
   before_each(clear)
@@ -121,6 +123,65 @@ describe('api/buf', function()
       eq({ 5, 2 }, api.nvim_win_get_cursor(win2))
     end)
 
+    it('cursor position is maintained consistently with viewport', function()
+      local screen = Screen.new(20, 12)
+      screen:set_default_attr_ids {
+        [1] = { bold = true, foreground = Screen.colors.Blue1 },
+        [2] = { reverse = true, bold = true },
+        [3] = { reverse = true },
+      }
+      screen:attach()
+
+      local lines = { 'line1', 'line2', 'line3', 'line4', 'line5', 'line6' }
+      local buf = api.nvim_get_current_buf()
+
+      api.nvim_buf_set_lines(buf, 0, -1, true, lines)
+
+      command('6')
+      command('new')
+      screen:expect {
+        grid = [[
+        ^                    |
+        {1:~                   }|*4
+        {2:[No Name]           }|
+        line5               |
+        line6               |
+        {1:~                   }|*2
+        {3:[No Name] [+]       }|
+                            |
+      ]],
+      }
+
+      lines[5] = 'boogalo 5'
+      api.nvim_buf_set_lines(buf, 0, -1, true, lines)
+      screen:expect {
+        grid = [[
+        ^                    |
+        {1:~                   }|*4
+        {2:[No Name]           }|
+        boogalo 5           |
+        line6               |
+        {1:~                   }|*2
+        {3:[No Name] [+]       }|
+                            |
+      ]],
+      }
+
+      command('wincmd w')
+      screen:expect {
+        grid = [[
+                            |
+        {1:~                   }|*4
+        {3:[No Name]           }|
+        boogalo 5           |
+        ^line6               |
+        {1:~                   }|*2
+        {2:[No Name] [+]       }|
+                            |
+      ]],
+      }
+    end)
+
     it('line_count has defined behaviour for unloaded buffers', function()
       -- we'll need to know our bufnr for when it gets unloaded
       local bufnr = api.nvim_buf_get_number(0)
@@ -323,20 +384,20 @@ describe('api/buf', function()
         ]],
         }
 
-        -- inserting just before topline scrolls up
         api.nvim_buf_set_lines(buf, 3, 3, true, { 'mmm' })
         screen:expect {
           grid = [[
           ^                    |
           {1:~                   }|*4
           {2:[No Name]           }|
-          mmm                 |
           wwweeee             |
           xxx                 |
           yyy                 |
+          zzz                 |
           {3:[No Name] [+]       }|
                               |
         ]],
+          unchanged = true,
         }
       end)
 
@@ -402,7 +463,6 @@ describe('api/buf', function()
         ]],
         }
 
-        -- inserting just before topline scrolls up
         api.nvim_buf_set_lines(buf, 3, 3, true, { 'mmm' })
         screen:expect {
           grid = [[
@@ -412,10 +472,10 @@ describe('api/buf', function()
           mmm                 |
           wwweeee             |
           {2:[No Name] [+]       }|
-          mmm                 |
           wwweeee             |
           xxx                 |
           yyy                 |
+          zzz                 |
           {3:[No Name] [+]       }|
                               |
         ]],
@@ -1316,12 +1376,7 @@ describe('api/buf', function()
           -- immediate call to nvim_win_get_cursor should have returned the same position
           eq({ 2, 12 }, cursor)
           -- coladd should be 0
-          eq(
-            0,
-            exec_lua([[
-            return vim.fn.winsaveview().coladd
-          ]])
-          )
+          eq(0, fn.winsaveview().coladd)
         end)
 
         it('does not change cursor screen column when cursor >EOL and row got shorter', function()
@@ -1335,9 +1390,7 @@ describe('api/buf', function()
           -- turn on virtualedit
           command('set virtualedit=all')
           -- move cursor after eol
-          exec_lua([[
-            vim.fn.winrestview({ coladd = 5 })
-          ]])
+          fn.winrestview({ coladd = 5 })
 
           local cursor = exec_lua([[
             vim.api.nvim_buf_set_text(0, 0, 15, 2, 11, {
@@ -1356,12 +1409,7 @@ describe('api/buf', function()
           -- immediate call to nvim_win_get_cursor should have returned the same position
           eq({ 2, 26 }, cursor)
           -- coladd should be increased so that cursor stays in the same screen column
-          eq(
-            13,
-            exec_lua([[
-            return vim.fn.winsaveview().coladd
-          ]])
-          )
+          eq(13, fn.winsaveview().coladd)
         end)
 
         it(
@@ -1377,9 +1425,7 @@ describe('api/buf', function()
             -- turn on virtualedit
             command('set virtualedit=all')
             -- move cursor after eol
-            exec_lua([[
-            vim.fn.winrestview({ coladd = 21 })
-          ]])
+            fn.winrestview({ coladd = 21 })
 
             local cursor = exec_lua([[
             vim.api.nvim_buf_set_text(0, 0, 15, 2, 11, {
@@ -1398,12 +1444,7 @@ describe('api/buf', function()
             -- immediate call to nvim_win_get_cursor should have returned the same position
             eq({ 1, 38 }, cursor)
             -- coladd should be increased so that cursor stays in the same screen column
-            eq(
-              2,
-              exec_lua([[
-            return vim.fn.winsaveview().coladd
-          ]])
-            )
+            eq(2, fn.winsaveview().coladd)
           end
         )
 
@@ -1420,9 +1461,7 @@ describe('api/buf', function()
             -- turn on virtualedit
             command('set virtualedit=all')
             -- move cursor after eol just a bit
-            exec_lua([[
-            vim.fn.winrestview({ coladd = 3 })
-          ]])
+            fn.winrestview({ coladd = 3 })
 
             local cursor = exec_lua([[
             vim.api.nvim_buf_set_text(0, 0, 15, 2, 11, {
@@ -1441,12 +1480,7 @@ describe('api/buf', function()
             -- immediate call to nvim_win_get_cursor should have returned the same position
             eq({ 1, 22 }, cursor)
             -- coladd should become 0
-            eq(
-              0,
-              exec_lua([[
-            return vim.fn.winsaveview().coladd
-          ]])
-            )
+            eq(0, fn.winsaveview().coladd)
           end
         )
 
@@ -1464,9 +1498,7 @@ describe('api/buf', function()
             -- turn on virtualedit
             command('set virtualedit=all')
             -- move cursor after eol
-            exec_lua([[
-            vim.fn.winrestview({ coladd = 28 })
-          ]])
+            fn.winrestview({ coladd = 28 })
 
             local cursor = exec_lua([[
             vim.api.nvim_buf_set_text(0, 0, 15, 3, 11, {
@@ -1485,12 +1517,7 @@ describe('api/buf', function()
             -- immediate call to nvim_win_get_cursor should have returned the same position
             eq({ 2, 26 }, cursor)
             -- coladd should be increased so that cursor stays in the same screen column
-            eq(
-              13,
-              exec_lua([[
-            return vim.fn.winsaveview().coladd
-          ]])
-            )
+            eq(13, fn.winsaveview().coladd)
           end
         )
       end)
@@ -1686,12 +1713,11 @@ describe('api/buf', function()
       api.nvim_buf_set_text(0, 0, 0, 1, 3, { 'XXX', 'YYY' })
 
       screen:expect([[
-  XXX                 |
-  YYY                 |
-  ^                    |
-  ~                   |
-                      |
-
+        XXX                 |
+        YYY                 |
+        ^                    |
+        {1:~                   }|
+                            |
       ]])
     end)
 
@@ -2024,6 +2050,37 @@ describe('api/buf', function()
       eq(1, fn.filereadable(new_name))
       os.remove(new_name)
     end)
+
+    describe("with 'autochdir'", function()
+      local topdir
+      local oldbuf
+      local newbuf
+
+      before_each(function()
+        command('set shellslash')
+        topdir = fn.getcwd()
+        t.mkdir(topdir .. '/Xacd')
+
+        oldbuf = api.nvim_get_current_buf()
+        command('vnew')
+        newbuf = api.nvim_get_current_buf()
+        command('set autochdir')
+      end)
+
+      after_each(function()
+        n.rmdir(topdir .. '/Xacd')
+      end)
+
+      it('does not change cwd with non-current buffer', function()
+        api.nvim_buf_set_name(oldbuf, topdir .. '/Xacd/foo.txt')
+        eq(topdir, fn.getcwd())
+      end)
+
+      it('changes cwd with current buffer', function()
+        api.nvim_buf_set_name(newbuf, topdir .. '/Xacd/foo.txt')
+        eq(topdir .. '/Xacd', fn.getcwd())
+      end)
+    end)
   end)
 
   describe('nvim_buf_is_loaded', function()
diff --git a/test/functional/api/buffer_updates_spec.lua b/test/functional/api/buffer_updates_spec.lua
index 262ca40e28..e030b45396 100644
--- a/test/functional/api/buffer_updates_spec.lua
+++ b/test/functional/api/buffer_updates_spec.lua
@@ -1,13 +1,15 @@
-local helpers = require('test.functional.helpers')(after_each)
-local clear = helpers.clear
-local eq, ok = helpers.eq, helpers.ok
-local fn = helpers.fn
-local api = helpers.api
-local command, eval, next_msg = helpers.command, helpers.eval, helpers.next_msg
-local nvim_prog = helpers.nvim_prog
-local pcall_err = helpers.pcall_err
+local t = require('test.testutil')
+local n = require('test.functional.testnvim')()
+
+local clear = n.clear
+local eq, ok = t.eq, t.ok
+local fn = n.fn
+local api = n.api
+local command, eval, next_msg = n.command, n.eval, n.next_msg
+local nvim_prog = n.nvim_prog
+local pcall_err = t.pcall_err
 local sleep = vim.uv.sleep
-local write_file = helpers.write_file
+local write_file = t.write_file
 
 local origlines = {
   'original line 1',
@@ -34,7 +36,7 @@ local function sendkeys(keys)
 end
 
 local function open(activate, lines)
-  local filename = helpers.tmpname()
+  local filename = t.tmpname()
   write_file(filename, table.concat(lines, '\n') .. '\n', true)
   command('edit ' .. filename)
   local b = api.nvim_get_current_buf()
@@ -511,11 +513,11 @@ describe('API: buffer events:', function()
 
     -- create several new sessions, in addition to our main API
     local sessions = {}
-    local pipe = helpers.new_pipename()
+    local pipe = n.new_pipename()
     eval("serverstart('" .. pipe .. "')")
-    sessions[1] = helpers.connect(pipe)
-    sessions[2] = helpers.connect(pipe)
-    sessions[3] = helpers.connect(pipe)
+    sessions[1] = n.connect(pipe)
+    sessions[2] = n.connect(pipe)
+    sessions[3] = n.connect(pipe)
 
     local function request(sessionnr, method, ...)
       local status, rv = sessions[sessionnr]:request(method, ...)
@@ -814,7 +816,7 @@ describe('API: buffer events:', function()
     clear()
     sleep(250)
     -- response
-    eq(true, helpers.request('nvim_buf_attach', 0, false, {}))
+    eq(true, n.request('nvim_buf_attach', 0, false, {}))
     -- notification
     eq({
       [1] = 'notification',
diff --git a/test/functional/api/command_spec.lua b/test/functional/api/command_spec.lua
index f73b9c8b13..a16c6a88e3 100644
--- a/test/functional/api/command_spec.lua
+++ b/test/functional/api/command_spec.lua
@@ -1,17 +1,18 @@
-local helpers = require('test.functional.helpers')(after_each)
+local t = require('test.testutil')
+local n = require('test.functional.testnvim')()
 
 local NIL = vim.NIL
-local clear = helpers.clear
-local command = helpers.command
-local eq = helpers.eq
-local api = helpers.api
-local matches = helpers.matches
-local source = helpers.source
-local pcall_err = helpers.pcall_err
-local exec_lua = helpers.exec_lua
-local assert_alive = helpers.assert_alive
-local feed = helpers.feed
-local fn = helpers.fn
+local clear = n.clear
+local command = n.command
+local eq = t.eq
+local api = n.api
+local matches = t.matches
+local source = n.source
+local pcall_err = t.pcall_err
+local exec_lua = n.exec_lua
+local assert_alive = n.assert_alive
+local feed = n.feed
+local fn = n.fn
 
 describe('nvim_get_commands', function()
   local cmd_dict = {
diff --git a/test/functional/api/extmark_spec.lua b/test/functional/api/extmark_spec.lua
index 2acfbfc949..7b2fe209ba 100644
--- a/test/functional/api/extmark_spec.lua
+++ b/test/functional/api/extmark_spec.lua
@@ -1,20 +1,21 @@
-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 request = helpers.request
-local eq = helpers.eq
-local ok = helpers.ok
-local pcall_err = helpers.pcall_err
-local insert = helpers.insert
-local feed = helpers.feed
-local clear = helpers.clear
-local command = helpers.command
-local exec = helpers.exec
-local api = helpers.api
-local assert_alive = helpers.assert_alive
+local request = n.request
+local eq = t.eq
+local ok = t.ok
+local pcall_err = t.pcall_err
+local insert = n.insert
+local feed = n.feed
+local clear = n.clear
+local command = n.command
+local exec = n.exec
+local api = n.api
+local assert_alive = n.assert_alive
 
 local function expect(contents)
-  return eq(contents, helpers.curbuf_contents())
+  return eq(contents, n.curbuf_contents())
 end
 
 local function set_extmark(ns_id, id, line, col, opts)
@@ -460,7 +461,7 @@ describe('API/extmarks', function()
     -- This shouldn't seg fault
     screen:expect([[
       12345^ 1        |
-      ~              |*8
+      {1:~              }|*8
                      |
     ]])
   end)
@@ -513,7 +514,7 @@ describe('API/extmarks', function()
     insert('abc')
     screen:expect([[
       ab^c12345       |
-      ~              |*8
+      {1:~              }|*8
                      |
     ]])
     local rv = get_extmark_by_id(ns, marks[1])
@@ -1568,7 +1569,7 @@ describe('API/extmarks', function()
       sign_text = '>>',
       spell = true,
       virt_lines = {
-        { { 'lines', 'Macro' }, { '???' } },
+        { { 'lines', 'Macro' }, { '???' }, { ';;;', '' } },
         { { 'stack', { 'Type', 'Search' } }, { '!!!' } },
       },
       virt_lines_above = true,
@@ -1603,7 +1604,7 @@ describe('API/extmarks', function()
         sign_text = '>>',
         spell = true,
         virt_lines = {
-          { { 'lines', 'Macro' }, { '???' } },
+          { { 'lines', 'Macro' }, { '???' }, { ';;;', '' } },
           { { 'stack', { 'Type', 'Search' } }, { '!!!' } },
         },
         virt_lines_above = true,
@@ -1734,16 +1735,17 @@ describe('API/extmarks', function()
     command('d2')
     screen:expect([[
       S2^aaa bbb ccc                           |
-        aaa bbb ccc                           |*3
-                                              |*2
+      {7:  }aaa bbb ccc                           |*3
+      {7:  }                                      |
+                                              |
     ]])
     -- mark is restored with undo_restore == true
     command('silent undo')
     screen:expect([[
-      S1  ^aaa bbb ccc                         |
-      S1S2aaa bbb ccc                         |
-      S2  aaa bbb ccc                         |
-          aaa bbb ccc                         |*2
+      S1{7:  }^aaa bbb ccc                         |
+      S2S1aaa bbb ccc                         |
+      S2{7:  }aaa bbb ccc                         |
+      {7:    }aaa bbb ccc                         |*2
                                               |
     ]])
     -- decor is not removed twice
@@ -1894,6 +1896,24 @@ describe('Extmarks buffer api with many marks', function()
     end
     eq(ns_marks[ns1], get_marks(ns1))
     eq(ns_marks[ns2], get_marks(ns2))
+
+    api.nvim_buf_clear_namespace(0, ns1, 0, 10)
+    for id, mark in pairs(ns_marks[ns1]) do
+      if mark[1] < 10 then
+        ns_marks[ns1][id] = nil
+      end
+    end
+    eq(ns_marks[ns1], get_marks(ns1))
+    eq(ns_marks[ns2], get_marks(ns2))
+
+    api.nvim_buf_clear_namespace(0, ns1, 20, -1)
+    for id, mark in pairs(ns_marks[ns1]) do
+      if 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()
@@ -1964,7 +1984,7 @@ describe('API/win_extmark', function()
       grid = [[
       non ui-watched line |
       ui-watched lin^e     |
-      ~                   |
+      {1:~                   }|
                           |
     ]],
       extmarks = {
@@ -2052,7 +2072,7 @@ describe('API/win_extmark', function()
       grid = [[
       ui-watched linupdat^e|
       e                   |
-      ~                   |
+      {1:~                   }|
                           |
     ]],
       extmarks = {
@@ -2079,9 +2099,9 @@ describe('API/win_extmark', function()
       grid = [[
         ## grid 1
           [4:--------------------]|*3
-          [No Name] [+]       |
+          {3:[No Name] [+]       }|
           [2:--------------------]|*2
-          [No Name] [+]       |
+          {2:[No Name] [+]       }|
           [3:--------------------]|
         ## grid 2
           non ui-watched line |
@@ -2091,7 +2111,7 @@ describe('API/win_extmark', function()
         ## grid 4
           non ui-watched line |
           ui-watched lin^e     |
-          ~                   |
+          {1:~                   }|
     ]],
       extmarks = {
         [2] = {
@@ -2112,13 +2132,13 @@ describe('API/win_extmark', function()
       grid = [[
         ## grid 1
           [4:--------------------]|*3
-          [No Name] [+]       |
+          {3:[No Name] [+]       }|
           [2:--------------------]|*2
-          [No Name] [+]       |
+          {2:[No Name] [+]       }|
           [3:--------------------]|
         ## grid 2
           non ui-watched line |
-          ui-watched linupd@@@|
+          ui-watched linupd{1:@@@}|
         ## grid 3
                               |
         ## grid 4
diff --git a/test/functional/api/highlight_spec.lua b/test/functional/api/highlight_spec.lua
index 1973d3e1c7..dd0611f184 100644
--- a/test/functional/api/highlight_spec.lua
+++ b/test/functional/api/highlight_spec.lua
@@ -1,14 +1,16 @@
-local helpers = require('test.functional.helpers')(after_each)
-local clear = helpers.clear
+local t = require('test.testutil')
+local n = require('test.functional.testnvim')()
 local Screen = require('test.functional.ui.screen')
-local eq, eval = helpers.eq, helpers.eval
-local command = helpers.command
-local exec_capture = helpers.exec_capture
-local api = helpers.api
-local fn = helpers.fn
-local pcall_err = helpers.pcall_err
-local ok = helpers.ok
-local assert_alive = helpers.assert_alive
+
+local clear = n.clear
+local eq, eval = t.eq, n.eval
+local command = n.command
+local exec_capture = n.exec_capture
+local api = n.api
+local fn = n.fn
+local pcall_err = t.pcall_err
+local ok = t.ok
+local assert_alive = n.assert_alive
 
 describe('API: highlight', function()
   clear()
diff --git a/test/functional/api/keymap_spec.lua b/test/functional/api/keymap_spec.lua
index 0decd710e9..995711507f 100644
--- a/test/functional/api/keymap_spec.lua
+++ b/test/functional/api/keymap_spec.lua
@@ -1,17 +1,19 @@
-local helpers = require('test.functional.helpers')(after_each)
-
-local clear = helpers.clear
-local command = helpers.command
-local eq, neq = helpers.eq, helpers.neq
-local exec_lua = helpers.exec_lua
-local exec = helpers.exec
-local feed = helpers.feed
-local fn = helpers.fn
-local api = helpers.api
-local source = helpers.source
-local pcall_err = helpers.pcall_err
-
-local shallowcopy = helpers.shallowcopy
+local t = require('test.testutil')
+local n = require('test.functional.testnvim')()
+
+local clear = n.clear
+local command = n.command
+local eq, neq = t.eq, t.neq
+local exec_lua = n.exec_lua
+local exec = n.exec
+local feed = n.feed
+local fn = n.fn
+local api = n.api
+local matches = t.matches
+local source = n.source
+local pcall_err = t.pcall_err
+
+local shallowcopy = t.shallowcopy
 local sleep = vim.uv.sleep
 
 local sid_api_client = -9
@@ -398,7 +400,9 @@ describe('nvim_get_keymap', function()
       0,
       exec_lua([[
       GlobalCount = 0
-      vim.api.nvim_set_keymap('n', 'asdf', '', {callback = function() GlobalCount = GlobalCount + 1 end })
+      vim.api.nvim_set_keymap('n', 'asdf', '', {
+        callback = function() GlobalCount = GlobalCount + 1 end,
+      })
       return GlobalCount
     ]])
     )
@@ -738,7 +742,7 @@ describe('nvim_set_keymap, nvim_del_keymap', function()
     end
   end
 
-  it('can set mappings containing literal keycodes', function()
+  it('can set mappings containing C0 control codes', function()
     api.nvim_set_keymap('n', '\n\r\n', 'rhs', {})
     local expected = generate_mapargs('n', '<NL><CR><NL>', 'rhs')
     eq(expected, get_mapargs('n', '<NL><CR><NL>'))
@@ -951,7 +955,9 @@ describe('nvim_set_keymap, nvim_del_keymap', function()
       0,
       exec_lua [[
       GlobalCount = 0
-      vim.api.nvim_set_keymap('n', 'asdf', '', {callback = function() GlobalCount = GlobalCount + 1 end })
+      vim.api.nvim_set_keymap('n', 'asdf', '', {
+        callback = function() GlobalCount = GlobalCount + 1 end,
+      })
       return GlobalCount
     ]]
     )
@@ -963,34 +969,38 @@ describe('nvim_set_keymap, nvim_del_keymap', function()
 
   it(':map command shows lua mapping correctly', function()
     exec_lua [[
-      vim.api.nvim_set_keymap('n', 'asdf', '', {callback = function() print('jkl;') end })
+      vim.api.nvim_set_keymap('n', 'asdf', '', {
+        callback = function() print('jkl;') end,
+      })
     ]]
-    assert.truthy(
-      string.match(
-        exec_lua [[return vim.api.nvim_exec2(':nmap asdf', { output = true }).output]],
-        '^\nn  asdf          <Lua %d+>'
-      )
+    matches(
+      '^\nn  asdf          <Lua %d+>',
+      exec_lua [[return vim.api.nvim_exec2(':nmap asdf', { output = true }).output]]
     )
   end)
 
   it('mapcheck() returns lua mapping correctly', function()
     exec_lua [[
-      vim.api.nvim_set_keymap('n', 'asdf', '', {callback = function() print('jkl;') end })
+      vim.api.nvim_set_keymap('n', 'asdf', '', {
+        callback = function() print('jkl;') end,
+      })
     ]]
-    assert.truthy(string.match(fn.mapcheck('asdf', 'n'), '^<Lua %d+>'))
+    matches('^<Lua %d+>', fn.mapcheck('asdf', 'n'))
   end)
 
-  it('maparg() returns lua mapping correctly', function()
+  it('maparg() and maplist() return lua mapping correctly', function()
     eq(
       0,
       exec_lua([[
       GlobalCount = 0
-      vim.api.nvim_set_keymap('n', 'asdf', '', {callback = function() GlobalCount = GlobalCount + 1 end })
+      vim.api.nvim_set_keymap('n', 'asdf', '', {
+        callback = function() GlobalCount = GlobalCount + 1 end,
+      })
       return GlobalCount
     ]])
     )
 
-    assert.truthy(string.match(fn.maparg('asdf', 'n'), '^<Lua %d+>'))
+    matches('^<Lua %d+>', fn.maparg('asdf', 'n'))
 
     local mapargs = fn.maparg('asdf', 'n', false, true)
     mapargs.callback = nil
@@ -1010,11 +1020,20 @@ describe('nvim_set_keymap, nvim_del_keymap', function()
       call maparg('asdf', 'n', v:false, v:true).callback()
     ]])
     eq(2, exec_lua([[return GlobalCount]]))
+
+    api.nvim_eval([[
+      maplist()->filter({_, m -> m.lhs == 'asdf'})->foreach({_, m -> m.callback()})
+    ]])
+    eq(3, exec_lua([[return GlobalCount]]))
   end)
 
   it('can make lua expr mappings replacing keycodes', function()
     exec_lua [[
-      vim.api.nvim_set_keymap('n', 'aa', '', {callback = function() return '<Insert>π<C-V><M-π>foo<lt><Esc>' end, expr = true, replace_keycodes = true })
+      vim.api.nvim_set_keymap('n', 'aa', '', {
+        callback = function() return '<Insert>π<C-V><M-π>foo<lt><Esc>' end,
+        expr = true,
+        replace_keycodes = true,
+      })
     ]]
 
     feed('aa')
@@ -1024,7 +1043,10 @@ describe('nvim_set_keymap, nvim_del_keymap', function()
 
   it('can make lua expr mappings without replacing keycodes', function()
     exec_lua [[
-      vim.api.nvim_set_keymap('i', 'aa', '', {callback = function() return '<space>' end, expr = true })
+      vim.api.nvim_set_keymap('i', 'aa', '', {
+        callback = function() return '<space>' end,
+        expr = true,
+      })
     ]]
 
     feed('iaa<esc>')
@@ -1034,7 +1056,10 @@ describe('nvim_set_keymap, nvim_del_keymap', function()
 
   it('lua expr mapping returning nil is equivalent to returning an empty string', function()
     exec_lua [[
-      vim.api.nvim_set_keymap('i', 'aa', '', {callback = function() return nil end, expr = true })
+      vim.api.nvim_set_keymap('i', 'aa', '', {
+        callback = function() return nil end,
+        expr = true,
+      })
     ]]
 
     feed('iaa<esc>')
@@ -1047,7 +1072,9 @@ describe('nvim_set_keymap, nvim_del_keymap', function()
       0,
       exec_lua [[
       VisibleCount = 0
-      vim.api.nvim_set_keymap('i', '<F2>', '', {callback = function() VisibleCount = VisibleCount + vim.fn.pumvisible() end})
+      vim.api.nvim_set_keymap('i', '<F2>', '', {
+        callback = function() VisibleCount = VisibleCount + vim.fn.pumvisible() end,
+      })
       return VisibleCount
     ]]
     )
@@ -1060,7 +1087,9 @@ describe('nvim_set_keymap, nvim_del_keymap', function()
       0,
       exec_lua [[
       OpCount = 0
-      vim.api.nvim_set_keymap('o', '<F2>', '', {callback = function() OpCount = OpCount + 1 end})
+      vim.api.nvim_set_keymap('o', '<F2>', '', {
+        callback = function() OpCount = OpCount + 1 end,
+      })
       return OpCount
     ]]
     )
@@ -1075,7 +1104,9 @@ describe('nvim_set_keymap, nvim_del_keymap', function()
       0,
       exec_lua [[
       GlobalCount = 0
-      vim.api.nvim_set_keymap('n', 'asdf', '', {callback = function() GlobalCount = GlobalCount + 1 end })
+      vim.api.nvim_set_keymap('n', 'asdf', '', {
+        callback = function() GlobalCount = GlobalCount + 1 end,
+      })
       return GlobalCount
     ]]
     )
@@ -1085,7 +1116,9 @@ describe('nvim_set_keymap, nvim_del_keymap', function()
     eq(1, exec_lua [[return GlobalCount]])
 
     exec_lua [[
-      vim.api.nvim_set_keymap('n', 'asdf', '', {callback = function() GlobalCount = GlobalCount - 1 end })
+      vim.api.nvim_set_keymap('n', 'asdf', '', {
+        callback = function() GlobalCount = GlobalCount - 1 end,
+      })
     ]]
 
     feed('asdf\n')
@@ -1098,7 +1131,9 @@ describe('nvim_set_keymap, nvim_del_keymap', function()
       0,
       exec_lua [[
       GlobalCount = 0
-      vim.api.nvim_set_keymap('n', 'asdf', '', {callback = function() GlobalCount = GlobalCount + 1 end })
+      vim.api.nvim_set_keymap('n', 'asdf', '', {
+        callback = function() GlobalCount = GlobalCount + 1 end,
+      })
       return GlobalCount
     ]]
     )
@@ -1107,14 +1142,12 @@ describe('nvim_set_keymap, nvim_del_keymap', function()
 
     eq(1, exec_lua [[return GlobalCount]])
 
-    exec_lua [[
-      vim.api.nvim_del_keymap('n', 'asdf' )
-    ]]
+    exec_lua [[vim.api.nvim_del_keymap('n', 'asdf' )]]
 
     feed('asdf\n')
 
     eq(1, exec_lua [[return GlobalCount]])
-    eq('\nNo mapping found', helpers.exec_capture('nmap asdf'))
+    eq('\nNo mapping found', n.exec_capture('nmap asdf'))
   end)
 
   it('no double-free when unmapping simplifiable lua mappings', function()
@@ -1122,7 +1155,9 @@ describe('nvim_set_keymap, nvim_del_keymap', function()
       0,
       exec_lua [[
       GlobalCount = 0
-      vim.api.nvim_set_keymap('n', '<C-I>', '', {callback = function() GlobalCount = GlobalCount + 1 end })
+      vim.api.nvim_set_keymap('n', '<C-I>', '', {
+        callback = function() GlobalCount = GlobalCount + 1 end,
+      })
       return GlobalCount
     ]]
     )
@@ -1131,29 +1166,30 @@ describe('nvim_set_keymap, nvim_del_keymap', function()
 
     eq(1, exec_lua [[return GlobalCount]])
 
-    exec_lua [[
-      vim.api.nvim_del_keymap('n', '<C-I>')
-    ]]
+    exec_lua [[vim.api.nvim_del_keymap('n', '<C-I>')]]
 
     feed('<C-I>\n')
 
     eq(1, exec_lua [[return GlobalCount]])
-    eq('\nNo mapping found', helpers.exec_capture('nmap <C-I>'))
+    eq('\nNo mapping found', n.exec_capture('nmap <C-I>'))
   end)
 
   it('can set descriptions on mappings', function()
     api.nvim_set_keymap('n', 'lhs', 'rhs', { desc = 'map description' })
     eq(generate_mapargs('n', 'lhs', 'rhs', { desc = 'map description' }), get_mapargs('n', 'lhs'))
-    eq('\nn  lhs           rhs\n                 map description', helpers.exec_capture('nmap lhs'))
+    eq('\nn  lhs           rhs\n                 map description', n.exec_capture('nmap lhs'))
   end)
 
   it('can define !-mode abbreviations with lua callbacks', function()
     exec_lua [[
       GlobalCount = 0
-      vim.api.nvim_set_keymap('!a', 'foo', '', {expr = true, callback = function()
-        GlobalCount = GlobalCount + 1
-        return tostring(GlobalCount)
-      end})
+      vim.api.nvim_set_keymap('!a', 'foo', '', {
+        expr = true,
+        callback = function()
+          GlobalCount = GlobalCount + 1
+          return tostring(GlobalCount)
+        end,
+      })
     ]]
 
     feed 'iThe foo and the bar and the foo again<esc>'
@@ -1166,10 +1202,13 @@ describe('nvim_set_keymap, nvim_del_keymap', function()
   it('can define insert mode abbreviations with lua callbacks', function()
     exec_lua [[
       GlobalCount = 0
-      vim.api.nvim_set_keymap('ia', 'foo', '', {expr = true, callback = function()
-        GlobalCount = GlobalCount + 1
-        return tostring(GlobalCount)
-      end})
+      vim.api.nvim_set_keymap('ia', 'foo', '', {
+        expr = true,
+        callback = function()
+          GlobalCount = GlobalCount + 1
+          return tostring(GlobalCount)
+        end,
+      })
     ]]
 
     feed 'iThe foo and the bar and the foo again<esc>'
@@ -1182,10 +1221,13 @@ describe('nvim_set_keymap, nvim_del_keymap', function()
   it('can define cmdline mode abbreviations with lua callbacks', function()
     exec_lua [[
       GlobalCount = 0
-      vim.api.nvim_set_keymap('ca', 'foo', '', {expr = true, callback = function()
-        GlobalCount = GlobalCount + 1
-        return tostring(GlobalCount)
-      end})
+      vim.api.nvim_set_keymap('ca', 'foo', '', {
+        expr = true,
+        callback = function()
+          GlobalCount = GlobalCount + 1
+          return tostring(GlobalCount)
+        end,
+      })
     ]]
 
     feed 'iThe foo and the bar and the foo again<esc>'
@@ -1290,7 +1332,7 @@ describe('nvim_buf_set_keymap, nvim_buf_del_keymap', function()
 
   it('does not crash when setting mapping in a non-existing buffer #13541', function()
     pcall_err(api.nvim_buf_set_keymap, 100, '', 'lsh', 'irhs<Esc>', {})
-    helpers.assert_alive()
+    n.assert_alive()
   end)
 
   it('can make lua mappings', function()
@@ -1298,7 +1340,9 @@ describe('nvim_buf_set_keymap, nvim_buf_del_keymap', function()
       0,
       exec_lua [[
       GlobalCount = 0
-      vim.api.nvim_buf_set_keymap(0, 'n', 'asdf', '', {callback = function() GlobalCount = GlobalCount + 1 end })
+      vim.api.nvim_buf_set_keymap(0, 'n', 'asdf', '', {
+        callback = function() GlobalCount = GlobalCount + 1 end,
+      })
       return GlobalCount
     ]]
     )
@@ -1310,7 +1354,11 @@ describe('nvim_buf_set_keymap, nvim_buf_del_keymap', function()
 
   it('can make lua expr mappings replacing keycodes', function()
     exec_lua [[
-      vim.api.nvim_buf_set_keymap(0, 'n', 'aa', '', {callback = function() return '<Insert>π<C-V><M-π>foo<lt><Esc>' end, expr = true, replace_keycodes = true })
+      vim.api.nvim_buf_set_keymap(0, 'n', 'aa', '', {
+        callback = function() return '<Insert>π<C-V><M-π>foo<lt><Esc>' end,
+        expr = true,
+        replace_keycodes = true,
+      })
     ]]
 
     feed('aa')
@@ -1320,7 +1368,10 @@ describe('nvim_buf_set_keymap, nvim_buf_del_keymap', function()
 
   it('can make lua expr mappings without replacing keycodes', function()
     exec_lua [[
-      vim.api.nvim_buf_set_keymap(0, 'i', 'aa', '', {callback = function() return '<space>' end, expr = true })
+      vim.api.nvim_buf_set_keymap(0, 'i', 'aa', '', {
+        callback = function() return '<space>' end,
+        expr = true,
+      })
     ]]
 
     feed('iaa<esc>')
@@ -1333,7 +1384,9 @@ describe('nvim_buf_set_keymap, nvim_buf_del_keymap', function()
       0,
       exec_lua [[
       GlobalCount = 0
-      vim.api.nvim_buf_set_keymap(0, 'n', 'asdf', '', {callback = function() GlobalCount = GlobalCount + 1 end })
+      vim.api.nvim_buf_set_keymap(0, 'n', 'asdf', '', {
+        callback = function() GlobalCount = GlobalCount + 1 end,
+      })
       return GlobalCount
     ]]
     )
@@ -1343,7 +1396,9 @@ describe('nvim_buf_set_keymap, nvim_buf_del_keymap', function()
     eq(1, exec_lua [[return GlobalCount]])
 
     exec_lua [[
-      vim.api.nvim_buf_set_keymap(0, 'n', 'asdf', '', {callback = function() GlobalCount = GlobalCount - 1 end })
+      vim.api.nvim_buf_set_keymap(0, 'n', 'asdf', '', {
+        callback = function() GlobalCount = GlobalCount - 1 end,
+      })
     ]]
 
     feed('asdf\n')
@@ -1356,7 +1411,9 @@ describe('nvim_buf_set_keymap, nvim_buf_del_keymap', function()
       0,
       exec_lua [[
       GlobalCount = 0
-      vim.api.nvim_buf_set_keymap(0, 'n', 'asdf', '', {callback = function() GlobalCount = GlobalCount + 1 end })
+      vim.api.nvim_buf_set_keymap(0, 'n', 'asdf', '', {
+        callback = function() GlobalCount = GlobalCount + 1 end,
+      })
       return GlobalCount
     ]]
     )
@@ -1365,14 +1422,12 @@ describe('nvim_buf_set_keymap, nvim_buf_del_keymap', function()
 
     eq(1, exec_lua [[return GlobalCount]])
 
-    exec_lua [[
-      vim.api.nvim_buf_del_keymap(0, 'n', 'asdf' )
-    ]]
+    exec_lua [[vim.api.nvim_buf_del_keymap(0, 'n', 'asdf' )]]
 
     feed('asdf\n')
 
     eq(1, exec_lua [[return GlobalCount]])
-    eq('\nNo mapping found', helpers.exec_capture('nmap asdf'))
+    eq('\nNo mapping found', n.exec_capture('nmap asdf'))
   end)
 
   it('no double-free when unmapping simplifiable lua mappings', function()
@@ -1380,7 +1435,9 @@ describe('nvim_buf_set_keymap, nvim_buf_del_keymap', function()
       0,
       exec_lua [[
       GlobalCount = 0
-      vim.api.nvim_buf_set_keymap(0, 'n', '<C-I>', '', {callback = function() GlobalCount = GlobalCount + 1 end })
+      vim.api.nvim_buf_set_keymap(0, 'n', '<C-I>', '', {
+        callback = function() GlobalCount = GlobalCount + 1 end,
+      })
       return GlobalCount
     ]]
     )
@@ -1389,13 +1446,11 @@ describe('nvim_buf_set_keymap, nvim_buf_del_keymap', function()
 
     eq(1, exec_lua [[return GlobalCount]])
 
-    exec_lua [[
-      vim.api.nvim_buf_del_keymap(0, 'n', '<C-I>')
-    ]]
+    exec_lua [[vim.api.nvim_buf_del_keymap(0, 'n', '<C-I>')]]
 
     feed('<C-I>\n')
 
     eq(1, exec_lua [[return GlobalCount]])
-    eq('\nNo mapping found', helpers.exec_capture('nmap <C-I>'))
+    eq('\nNo mapping found', n.exec_capture('nmap <C-I>'))
   end)
 end)
diff --git a/test/functional/api/menu_spec.lua b/test/functional/api/menu_spec.lua
index 44b9039393..76eef164c9 100644
--- a/test/functional/api/menu_spec.lua
+++ b/test/functional/api/menu_spec.lua
@@ -1,9 +1,9 @@
-local helpers = require('test.functional.helpers')(after_each)
+local n = require('test.functional.testnvim')()
 local Screen = require('test.functional.ui.screen')
 
-local clear = helpers.clear
-local command = helpers.command
-local feed = helpers.feed
+local clear = n.clear
+local command = n.command
+local feed = n.feed
 
 describe('update_menu notification', function()
   local screen
diff --git a/test/functional/api/proc_spec.lua b/test/functional/api/proc_spec.lua
index 50c441792c..d2dd655b17 100644
--- a/test/functional/api/proc_spec.lua
+++ b/test/functional/api/proc_spec.lua
@@ -1,14 +1,15 @@
-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 fn = helpers.fn
-local neq = helpers.neq
-local nvim_argv = helpers.nvim_argv
-local request = helpers.request
-local retry = helpers.retry
+local clear = n.clear
+local eq = t.eq
+local fn = n.fn
+local neq = t.neq
+local nvim_argv = n.nvim_argv
+local request = n.request
+local retry = t.retry
 local NIL = vim.NIL
-local is_os = helpers.is_os
+local is_os = t.is_os
 
 describe('API', function()
   before_each(clear)
diff --git a/test/functional/api/server_notifications_spec.lua b/test/functional/api/server_notifications_spec.lua
index d1608a951c..7b4c4e8312 100644
--- a/test/functional/api/server_notifications_spec.lua
+++ b/test/functional/api/server_notifications_spec.lua
@@ -1,11 +1,12 @@
-local helpers = require('test.functional.helpers')(after_each)
-local assert_log = helpers.assert_log
-local eq, clear, eval, command, next_msg =
-  helpers.eq, helpers.clear, helpers.eval, helpers.command, helpers.next_msg
-local api = helpers.api
-local exec_lua = helpers.exec_lua
-local retry = helpers.retry
-local assert_alive = helpers.assert_alive
+local t = require('test.testutil')
+local n = require('test.functional.testnvim')()
+
+local eq, clear, eval, command, next_msg = t.eq, n.clear, n.eval, n.command, n.next_msg
+local api = n.api
+local exec_lua = n.exec_lua
+local retry = t.retry
+local assert_alive = n.assert_alive
+local check_close = n.check_close
 
 local testlog = 'Xtest-server-notify-log'
 
@@ -18,6 +19,7 @@ describe('notify', function()
   end)
 
   after_each(function()
+    check_close()
     os.remove(testlog)
   end)
 
@@ -31,18 +33,18 @@ describe('notify', function()
     end)
   end)
 
-  describe('passing 0 as the channel id', function()
-    it('sends the notification/args to all subscribed channels', function()
-      api.nvim_subscribe('event2')
+  describe('channel id 0', function()
+    it('broadcasts the notification/args to all channels', function()
       eval('rpcnotify(0, "event1", 1, 2, 3)')
       eval('rpcnotify(0, "event2", 4, 5, 6)')
       eval('rpcnotify(0, "event2", 7, 8, 9)')
+      eq({ 'notification', 'event1', { 1, 2, 3 } }, next_msg())
       eq({ 'notification', 'event2', { 4, 5, 6 } }, next_msg())
       eq({ 'notification', 'event2', { 7, 8, 9 } }, next_msg())
-      api.nvim_unsubscribe('event2')
-      api.nvim_subscribe('event1')
+
       eval('rpcnotify(0, "event2", 10, 11, 12)')
       eval('rpcnotify(0, "event1", 13, 14, 15)')
+      eq({ 'notification', 'event2', { 10, 11, 12 } }, next_msg())
       eq({ 'notification', 'event1', { 13, 14, 15 } }, next_msg())
     end)
 
@@ -75,17 +77,6 @@ describe('notify', function()
     end)
   end)
 
-  it('unsubscribe non-existing event #8745', function()
-    clear { env = {
-      NVIM_LOG_FILE = testlog,
-    } }
-    api.nvim_subscribe('event1')
-    api.nvim_unsubscribe('doesnotexist')
-    assert_log("tried to unsubscribe unknown event 'doesnotexist'", testlog, 10)
-    api.nvim_unsubscribe('event1')
-    assert_alive()
-  end)
-
   it('cancels stale events on channel close', function()
     local catchan = eval("jobstart(['cat'], {'rpc': v:true})")
     local catpath = eval('exepath("cat")')
@@ -94,7 +85,6 @@ describe('notify', function()
       exec_lua(
         [[
       vim.rpcnotify(..., "nvim_call_function", 'chanclose', {..., 'rpc'})
-      vim.rpcnotify(..., "nvim_subscribe", "daily_rant")
       return vim.api.nvim_get_chan_info(...)
     ]],
         catchan
diff --git a/test/functional/api/server_requests_spec.lua b/test/functional/api/server_requests_spec.lua
index 298dbac217..bdd340f6c6 100644
--- a/test/functional/api/server_requests_spec.lua
+++ b/test/functional/api/server_requests_spec.lua
@@ -1,17 +1,18 @@
 -- Test server -> client RPC scenarios. Note: unlike `rpcnotify`, to evaluate
 -- `rpcrequest` calls we need the client event loop to be running.
-local helpers = require('test.functional.helpers')(after_each)
-
-local clear, eval = helpers.clear, helpers.eval
-local eq, neq, run, stop = helpers.eq, helpers.neq, helpers.run, helpers.stop
-local nvim_prog, command, fn = helpers.nvim_prog, helpers.command, helpers.fn
-local source, next_msg = helpers.source, helpers.next_msg
-local ok = helpers.ok
-local api = helpers.api
-local spawn, merge_args = helpers.spawn, helpers.merge_args
-local set_session = helpers.set_session
-local pcall_err = helpers.pcall_err
-local assert_alive = helpers.assert_alive
+local t = require('test.testutil')
+local n = require('test.functional.testnvim')()
+
+local clear, eval = n.clear, n.eval
+local eq, neq, run, stop = t.eq, t.neq, n.run, n.stop
+local nvim_prog, command, fn = n.nvim_prog, n.command, n.fn
+local source, next_msg = n.source, n.next_msg
+local ok = t.ok
+local api = n.api
+local spawn, merge_args = n.spawn, n.merge_args
+local set_session = n.set_session
+local pcall_err = t.pcall_err
+local assert_alive = n.assert_alive
 
 describe('server -> client', function()
   local cid
@@ -91,19 +92,19 @@ describe('server -> client', function()
 
       local function on_request(method, args)
         eq('rcall', method)
-        local n = unpack(args) * 2
-        if n <= 16 then
+        local _n = unpack(args) * 2
+        if _n <= 16 then
           local cmd
-          if n == 4 then
-            cmd = 'let g:result2 = rpcrequest(' .. cid .. ', "rcall", ' .. n .. ')'
-          elseif n == 8 then
-            cmd = 'let g:result3 = rpcrequest(' .. cid .. ', "rcall", ' .. n .. ')'
-          elseif n == 16 then
-            cmd = 'let g:result4 = rpcrequest(' .. cid .. ', "rcall", ' .. n .. ')'
+          if _n == 4 then
+            cmd = 'let g:result2 = rpcrequest(' .. cid .. ', "rcall", ' .. _n .. ')'
+          elseif _n == 8 then
+            cmd = 'let g:result3 = rpcrequest(' .. cid .. ', "rcall", ' .. _n .. ')'
+          elseif _n == 16 then
+            cmd = 'let g:result4 = rpcrequest(' .. cid .. ', "rcall", ' .. _n .. ')'
           end
           command(cmd)
         end
-        return n
+        return _n
       end
       run(on_request, nil, on_setup)
     end)
@@ -259,7 +260,7 @@ describe('server -> client', function()
       pcall(fn.jobstop, jobid)
     end)
 
-    if helpers.skip(helpers.is_os('win')) then
+    if t.skip(t.is_os('win')) then
       return
     end
 
@@ -280,7 +281,7 @@ describe('server -> client', function()
   end)
 
   describe('connecting to another (peer) nvim', function()
-    local nvim_argv = merge_args(helpers.nvim_argv, { '--headless' })
+    local nvim_argv = merge_args(n.nvim_argv, { '--headless' })
     local function connect_test(server, mode, address)
       local serverpid = fn.getpid()
       local client = spawn(nvim_argv, false, nil, true)
@@ -363,6 +364,24 @@ describe('server -> client', function()
       server:close()
       client:close()
     end)
+
+    it('via stdio, with many small flushes does not crash #23781', function()
+      source([[
+      let chan = jobstart([v:progpath, '--embed', '--headless', '-n', '-u', 'NONE', '-i', 'NONE'], { 'rpc':v:false })
+      call chansend(chan, 0Z94)
+      sleep 50m
+      call chansend(chan, 0Z00)
+      call chansend(chan, 0Z01)
+      call chansend(chan, 0ZAC)
+      call chansend(chan, 0Z6E76696D5F636F6D6D616E64)
+      call chansend(chan, 0Z91)
+      call chansend(chan, 0ZA5)
+      call chansend(chan, 0Z71616C6C21)
+      let g:statuses = jobwait([chan])
+      ]])
+      eq(eval('g:statuses'), { 0 })
+      assert_alive()
+    end)
   end)
 
   describe('connecting to its own pipe address', function()
diff --git a/test/functional/api/tabpage_spec.lua b/test/functional/api/tabpage_spec.lua
index 36955c4ace..74858475c8 100644
--- a/test/functional/api/tabpage_spec.lua
+++ b/test/functional/api/tabpage_spec.lua
@@ -1,11 +1,15 @@
-local helpers = require('test.functional.helpers')(after_each)
-local clear, eq, ok = helpers.clear, helpers.eq, helpers.ok
-local api = helpers.api
-local fn = helpers.fn
-local request = helpers.request
+local t = require('test.testutil')
+local n = require('test.functional.testnvim')()
+
+local clear, eq, ok = n.clear, t.eq, t.ok
+local exec = n.exec
+local feed = n.feed
+local api = n.api
+local fn = n.fn
+local request = n.request
 local NIL = vim.NIL
-local pcall_err = helpers.pcall_err
-local command = helpers.command
+local pcall_err = t.pcall_err
+local command = n.command
 
 describe('api/tabpage', function()
   before_each(clear)
@@ -86,6 +90,30 @@ describe('api/tabpage', function()
         pcall_err(api.nvim_tabpage_set_win, tab1, win3)
       )
     end)
+
+    it('does not switch window when textlocked or in the cmdwin', function()
+      local target_win = api.nvim_get_current_win()
+      feed('q:')
+      local cur_win = api.nvim_get_current_win()
+      eq(
+        'Vim:E11: Invalid in command-line window; <CR> executes, CTRL-C quits',
+        pcall_err(api.nvim_tabpage_set_win, 0, target_win)
+      )
+      eq(cur_win, api.nvim_get_current_win())
+      command('quit!')
+
+      exec(([[
+        new
+        call setline(1, 'foo')
+        setlocal debug=throw indentexpr=nvim_tabpage_set_win(0,%d)
+      ]]):format(target_win))
+      cur_win = api.nvim_get_current_win()
+      eq(
+        'Vim(normal):E5555: API call: Vim:E565: Not allowed to change text or change window',
+        pcall_err(command, 'normal! ==')
+      )
+      eq(cur_win, api.nvim_get_current_win())
+    end)
   end)
 
   describe('{get,set,del}_var', function()
diff --git a/test/functional/api/ui_spec.lua b/test/functional/api/ui_spec.lua
index 3e1f1ec965..2145db7f8a 100644
--- a/test/functional/api/ui_spec.lua
+++ b/test/functional/api/ui_spec.lua
@@ -1,14 +1,16 @@
-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 clear = helpers.clear
-local command = helpers.command
-local eq = helpers.eq
-local eval = helpers.eval
-local exec = helpers.exec
-local feed = helpers.feed
-local api = helpers.api
-local request = helpers.request
-local pcall_err = helpers.pcall_err
+
+local clear = n.clear
+local command = n.command
+local eq = t.eq
+local eval = n.eval
+local exec = n.exec
+local feed = n.feed
+local api = n.api
+local request = n.request
+local pcall_err = t.pcall_err
 
 describe('nvim_ui_attach()', function()
   before_each(function()
diff --git a/test/functional/api/version_spec.lua b/test/functional/api/version_spec.lua
index c304f1aa88..5dad9978b7 100644
--- a/test/functional/api/version_spec.lua
+++ b/test/functional/api/version_spec.lua
@@ -1,6 +1,8 @@
-local helpers = require('test.functional.helpers')(after_each)
-local clear, fn, eq = helpers.clear, helpers.fn, helpers.eq
-local api = helpers.api
+local t = require('test.testutil')
+local n = require('test.functional.testnvim')()
+
+local clear, fn, eq = n.clear, n.fn, t.eq
+local api = n.api
 
 local function read_mpack_file(fname)
   local fd = io.open(fname, 'rb')
diff --git a/test/functional/api/vim_spec.lua b/test/functional/api/vim_spec.lua
index 9a4a457637..fd0535aa51 100644
--- a/test/functional/api/vim_spec.lua
+++ b/test/functional/api/vim_spec.lua
@@ -1,42 +1,43 @@
-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 uv = vim.uv
 
 local fmt = string.format
-local dedent = helpers.dedent
-local assert_alive = helpers.assert_alive
+local dedent = t.dedent
+local assert_alive = n.assert_alive
 local NIL = vim.NIL
-local clear, eq, neq = helpers.clear, helpers.eq, helpers.neq
-local command = helpers.command
-local command_output = helpers.api.nvim_command_output
-local exec = helpers.exec
-local exec_capture = helpers.exec_capture
-local eval = helpers.eval
-local expect = helpers.expect
-local fn = helpers.fn
-local api = helpers.api
-local matches = helpers.matches
+local clear, eq, neq = n.clear, t.eq, t.neq
+local command = n.command
+local command_output = n.api.nvim_command_output
+local exec = n.exec
+local exec_capture = n.exec_capture
+local eval = n.eval
+local expect = n.expect
+local fn = n.fn
+local api = n.api
+local matches = t.matches
 local pesc = vim.pesc
-local mkdir_p = helpers.mkdir_p
-local ok, nvim_async, feed = helpers.ok, helpers.nvim_async, helpers.feed
-local async_meths = helpers.async_meths
-local is_os = helpers.is_os
-local parse_context = helpers.parse_context
-local request = helpers.request
-local rmdir = helpers.rmdir
-local source = helpers.source
-local next_msg = helpers.next_msg
-local tmpname = helpers.tmpname
-local write_file = helpers.write_file
-local exec_lua = helpers.exec_lua
-local exc_exec = helpers.exc_exec
-local insert = helpers.insert
-local skip = helpers.skip
-
-local pcall_err = helpers.pcall_err
+local mkdir_p = n.mkdir_p
+local ok, nvim_async, feed = t.ok, n.nvim_async, n.feed
+local async_meths = n.async_meths
+local is_os = t.is_os
+local parse_context = n.parse_context
+local request = n.request
+local rmdir = n.rmdir
+local source = n.source
+local next_msg = n.next_msg
+local tmpname = t.tmpname
+local write_file = t.write_file
+local exec_lua = n.exec_lua
+local exc_exec = n.exc_exec
+local insert = n.insert
+local skip = t.skip
+
+local pcall_err = t.pcall_err
 local format_string = require('test.format_string').format_string
-local intchar2lua = helpers.intchar2lua
-local mergedicts_copy = helpers.mergedicts_copy
+local intchar2lua = t.intchar2lua
+local mergedicts_copy = t.mergedicts_copy
 local endswith = vim.endswith
 
 describe('API', function()
@@ -559,6 +560,16 @@ describe('API', function()
       eq('Vim:E121: Undefined variable: bogus', pcall_err(request, 'nvim_eval', 'bogus expression'))
       eq('', eval('v:errmsg')) -- v:errmsg was not updated.
     end)
+
+    it('can return Lua function to Lua code', function()
+      eq(
+        [["a string with \"double quotes\" and 'single quotes'"]],
+        exec_lua([=[
+          local fun = vim.api.nvim_eval([[luaeval('string.format')]])
+          return fun('%q', [[a string with "double quotes" and 'single quotes']])
+        ]=])
+      )
+    end)
   end)
 
   describe('nvim_call_function', function()
@@ -624,6 +635,16 @@ describe('API', function()
         pcall_err(request, 'nvim_call_function', 'Foo', too_many_args)
       )
     end)
+
+    it('can return Lua function to Lua code', function()
+      eq(
+        [["a string with \"double quotes\" and 'single quotes'"]],
+        exec_lua([=[
+          local fun = vim.api.nvim_call_function('luaeval', { 'string.format' })
+          return fun('%q', [[a string with "double quotes" and 'single quotes']])
+        ]=])
+      )
+    end)
   end)
 
   describe('nvim_call_dict_function', function()
@@ -702,18 +723,18 @@ describe('API', function()
     end)
 
     after_each(function()
-      helpers.rmdir('Xtestdir')
+      n.rmdir('Xtestdir')
     end)
 
     it('works', function()
       api.nvim_set_current_dir('Xtestdir')
-      eq(fn.getcwd(), start_dir .. helpers.get_pathsep() .. 'Xtestdir')
+      eq(start_dir .. n.get_pathsep() .. 'Xtestdir', fn.getcwd())
     end)
 
     it('sets previous directory', function()
       api.nvim_set_current_dir('Xtestdir')
       command('cd -')
-      eq(fn.getcwd(), start_dir)
+      eq(start_dir, fn.getcwd())
     end)
   end)
 
@@ -1269,7 +1290,7 @@ describe('API', function()
       api.nvim_paste('', true, 3)
       screen:expect([[
                             |
-        ~                   |*2
+        {1:~                   }|*2
         :Foo^                |
       ]])
     end)
@@ -1280,8 +1301,8 @@ describe('API', function()
       api.nvim_paste('normal! \023\022\006\027', true, -1)
       screen:expect([[
                             |
-        ~                   |*2
-        :normal! ^W^V^F^[^   |
+        {1:~                   }|*2
+        :normal! {18:^W^V^F^[}^   |
       ]])
     end)
     it('crlf=false does not break lines at CR, CRLF', function()
@@ -1467,7 +1488,7 @@ describe('API', function()
       eq(NIL, api.nvim_get_var('Unknown_script_func'))
 
       -- Check if autoload works properly
-      local pathsep = helpers.get_pathsep()
+      local pathsep = n.get_pathsep()
       local xconfig = 'Xhome' .. pathsep .. 'Xconfig'
       local xdata = 'Xhome' .. pathsep .. 'Xdata'
       local autoload_folder = table.concat({ xconfig, 'nvim', 'autoload' }, pathsep)
@@ -1593,14 +1614,12 @@ describe('API', function()
       api.nvim_set_option_value('equalalways', false, {})
       local status, rv = pcall(command_output, 'verbose set equalalways?')
       eq(true, status)
-      ok(
-        nil ~= string.find(rv, 'noequalalways\n' .. '\tLast set from API client %(channel id %d+%)')
-      )
+      matches('noequalalways\n' .. '\tLast set from API client %(channel id %d+%)', rv)
 
       api.nvim_exec_lua('vim.api.nvim_set_option_value("equalalways", true, {})', {})
       status, rv = pcall(command_output, 'verbose set equalalways?')
       eq(true, status)
-      eq('  equalalways\n\tLast set from Lua', rv)
+      eq('  equalalways\n\tLast set from Lua (run Nvim with -V1 for more details)', rv)
     end)
 
     it('updates whether the option has ever been set #25025', function()
@@ -1953,7 +1972,7 @@ describe('API', function()
 
   describe('RPC (K_EVENT)', function()
     it('does not complete ("interrupt") normal-mode operator-pending #6166', function()
-      helpers.insert([[
+      n.insert([[
         FIRST LINE
         SECOND LINE]])
       api.nvim_input('gg')
@@ -1981,16 +2000,16 @@ describe('API', function()
       -- Make any RPC request (can be non-async: op-pending does not block).
       api.nvim_get_current_buf()
       screen:expect([[
-       ^a$                  |
-       b$                  |
-       c$                  |
+       ^a{1:$}                  |
+       b{1:$}                  |
+       c{1:$}                  |
                            |
       ]])
     end)
 
     it('does not complete ("interrupt") normal-mode map-pending #6166', function()
       command("nnoremap dd :let g:foo='it worked...'<CR>")
-      helpers.insert([[
+      n.insert([[
         FIRST LINE
         SECOND LINE]])
       api.nvim_input('gg')
@@ -2002,13 +2021,13 @@ describe('API', function()
       expect([[
         FIRST LINE
         SECOND LINE]])
-      eq('it worked...', helpers.eval('g:foo'))
+      eq('it worked...', n.eval('g:foo'))
     end)
 
     it('does not complete ("interrupt") insert-mode map-pending #6166', function()
       command('inoremap xx foo')
       command('set timeoutlen=9999')
-      helpers.insert([[
+      n.insert([[
         FIRST LINE
         SECOND LINE]])
       api.nvim_input('ix')
@@ -2155,35 +2174,32 @@ describe('API', function()
 
   describe('nvim_replace_termcodes', function()
     it('escapes K_SPECIAL as K_SPECIAL KS_SPECIAL KE_FILLER', function()
-      eq('\128\254X', helpers.api.nvim_replace_termcodes('\128', true, true, true))
+      eq('\128\254X', n.api.nvim_replace_termcodes('\128', true, true, true))
     end)
 
     it('leaves non-K_SPECIAL string unchanged', function()
-      eq('abc', helpers.api.nvim_replace_termcodes('abc', true, true, true))
+      eq('abc', n.api.nvim_replace_termcodes('abc', true, true, true))
     end)
 
     it('converts <expressions>', function()
-      eq('\\', helpers.api.nvim_replace_termcodes('<Leader>', true, true, true))
+      eq('\\', n.api.nvim_replace_termcodes('<Leader>', true, true, true))
     end)
 
     it('converts <LeftMouse> to K_SPECIAL KS_EXTRA KE_LEFTMOUSE', function()
       -- K_SPECIAL KS_EXTRA KE_LEFTMOUSE
       -- 0x80      0xfd     0x2c
       -- 128       253      44
-      eq('\128\253\44', helpers.api.nvim_replace_termcodes('<LeftMouse>', true, true, true))
+      eq('\128\253\44', n.api.nvim_replace_termcodes('<LeftMouse>', true, true, true))
     end)
 
     it('converts keycodes', function()
-      eq(
-        '\nx\27x\rx<x',
-        helpers.api.nvim_replace_termcodes('<NL>x<Esc>x<CR>x<lt>x', true, true, true)
-      )
+      eq('\nx\27x\rx<x', n.api.nvim_replace_termcodes('<NL>x<Esc>x<CR>x<lt>x', true, true, true))
     end)
 
     it('does not convert keycodes if special=false', function()
       eq(
         '<NL>x<Esc>x<CR>x<lt>x',
-        helpers.api.nvim_replace_termcodes('<NL>x<Esc>x<CR>x<lt>x', true, true, false)
+        n.api.nvim_replace_termcodes('<NL>x<Esc>x<CR>x<lt>x', true, true, false)
       )
     end)
 
@@ -2212,18 +2228,18 @@ describe('API', function()
         api.nvim_feedkeys(':let x1="…"\n', '', true)
 
         -- Both nvim_replace_termcodes and nvim_feedkeys escape \x80
-        local inp = helpers.api.nvim_replace_termcodes(':let x2="…"<CR>', true, true, true)
+        local inp = n.api.nvim_replace_termcodes(':let x2="…"<CR>', true, true, true)
         api.nvim_feedkeys(inp, '', true) -- escape_ks=true
 
         -- nvim_feedkeys with K_SPECIAL escaping disabled
-        inp = helpers.api.nvim_replace_termcodes(':let x3="…"<CR>', true, true, true)
+        inp = n.api.nvim_replace_termcodes(':let x3="…"<CR>', true, true, true)
         api.nvim_feedkeys(inp, '', false) -- escape_ks=false
 
-        helpers.stop()
+        n.stop()
       end
 
       -- spin the loop a bit
-      helpers.run(nil, nil, on_setup)
+      n.run(nil, nil, on_setup)
 
       eq('…', api.nvim_get_var('x1'))
       -- Because of the double escaping this is neq
@@ -2366,7 +2382,7 @@ describe('API', function()
         {0:~                                       }|*6
         {1:very fail}                               |
       ]])
-      helpers.poke_eventloop()
+      n.poke_eventloop()
 
       -- shows up to &cmdheight lines
       async_meths.nvim_err_write('more fail\ntoo fail\n')
@@ -2678,7 +2694,7 @@ describe('API', function()
 
   describe('nvim_list_runtime_paths', function()
     setup(function()
-      local pathsep = helpers.get_pathsep()
+      local pathsep = n.get_pathsep()
       mkdir_p('Xtest' .. pathsep .. 'a')
       mkdir_p('Xtest' .. pathsep .. 'b')
     end)
@@ -2723,7 +2739,7 @@ describe('API', function()
   it('can throw exceptions', function()
     local status, err = pcall(api.nvim_get_option_value, 'invalid-option', {})
     eq(false, status)
-    ok(err:match("Unknown option 'invalid%-option'") ~= nil)
+    matches("Unknown option 'invalid%-option'", err)
   end)
 
   it('does not truncate error message <1 MB #5984', function()
@@ -2736,10 +2752,7 @@ describe('API', function()
   it('does not leak memory on incorrect argument types', function()
     local status, err = pcall(api.nvim_set_current_dir, { 'not', 'a', 'dir' })
     eq(false, status)
-    ok(
-      err:match(': Wrong type for argument 1 when calling nvim_set_current_dir, expecting String')
-        ~= nil
-    )
+    matches(': Wrong type for argument 1 when calling nvim_set_current_dir, expecting String', err)
   end)
 
   describe('nvim_parse_expression', function()
@@ -3135,10 +3148,60 @@ describe('API', function()
       -- nowadays this works because we don't execute any spurious autocmds at all #24824
       assert_alive()
     end)
+
+    it('no memory leak when autocommands load the buffer immediately', function()
+      exec([[
+        autocmd BufNew * ++once call bufload(expand("<abuf>")->str2nr())
+                             \| let loaded = bufloaded(expand("<abuf>")->str2nr())
+      ]])
+      api.nvim_create_buf(false, true)
+      eq(1, eval('g:loaded'))
+    end)
+
+    it('creating scratch buffer where autocommands set &swapfile works', function()
+      exec([[
+        autocmd BufNew * ++once execute expand("<abuf>") "buffer"
+                             \| file foobar
+                             \| setlocal swapfile
+      ]])
+      local new_buf = api.nvim_create_buf(false, true)
+      neq('', fn.swapname(new_buf))
+    end)
+
+    it('fires expected autocommands', function()
+      exec([=[
+        " Append the &buftype to check autocommands trigger *after* the buffer was configured to be
+        " scratch, if applicable.
+        autocmd BufNew * let fired += [["BufNew", expand("<abuf>")->str2nr(),
+                                      \ getbufvar(expand("<abuf>")->str2nr(), "&buftype")]]
+        autocmd BufAdd * let fired += [["BufAdd", expand("<abuf>")->str2nr(),
+                                      \ getbufvar(expand("<abuf>")->str2nr(), "&buftype")]]
+
+        " Don't want to see OptionSet; buffer options set from passing true for "scratch", etc.
+        " should be configured invisibly, and before autocommands.
+        autocmd OptionSet * let fired += [["OptionSet", expand("<amatch>")]]
+
+        let fired = []
+      ]=])
+      local new_buf = api.nvim_create_buf(false, false)
+      eq({ { 'BufNew', new_buf, '' } }, eval('g:fired'))
+
+      command('let fired = []')
+      new_buf = api.nvim_create_buf(false, true)
+      eq({ { 'BufNew', new_buf, 'nofile' } }, eval('g:fired'))
+
+      command('let fired = []')
+      new_buf = api.nvim_create_buf(true, false)
+      eq({ { 'BufNew', new_buf, '' }, { 'BufAdd', new_buf, '' } }, eval('g:fired'))
+
+      command('let fired = []')
+      new_buf = api.nvim_create_buf(true, true)
+      eq({ { 'BufNew', new_buf, 'nofile' }, { 'BufAdd', new_buf, 'nofile' } }, eval('g:fired'))
+    end)
   end)
 
   describe('nvim_get_runtime_file', function()
-    local p = helpers.alter_slashes
+    local p = n.alter_slashes
     it('can find files', function()
       eq({}, api.nvim_get_runtime_file('bork.borkbork', false))
       eq({}, api.nvim_get_runtime_file('bork.borkbork', true))
@@ -3365,13 +3428,13 @@ describe('API', function()
         {desc="(global option, fallback requested) points to global",          linenr=9, sid=1, args={'completeopt', {}}},
       }
 
-      for _, t in pairs(tests) do
-        it(t.desc, function()
+      for _, test in pairs(tests) do
+        it(test.desc, function()
           -- Switch to the target buffer/window so that curbuf/curwin are used.
           api.nvim_set_current_win(wins[2])
-          local info = api.nvim_get_option_info2(unpack(t.args))
-          eq(t.linenr, info.last_set_linenr)
-          eq(t.sid, info.last_set_sid)
+          local info = api.nvim_get_option_info2(unpack(test.args))
+          eq(test.linenr, info.last_set_linenr)
+          eq(test.sid, info.last_set_sid)
         end)
       end
 
@@ -3492,9 +3555,9 @@ describe('API', function()
         false,
         { width = 79, height = 31, row = 1, col = 1, relative = 'editor' }
       )
-      local t = api.nvim_open_term(b, {})
+      local term = api.nvim_open_term(b, {})
 
-      api.nvim_chan_send(t, io.open('test/functional/fixtures/smile2.cat', 'r'):read('*a'))
+      api.nvim_chan_send(term, io.open('test/functional/fixtures/smile2.cat', 'r'):read('*a'))
       screen:expect {
         grid = [[
         ^                                                                                                    |
@@ -3620,7 +3683,7 @@ describe('API', function()
       api.nvim_buf_set_name(buf, 'mybuf')
       local mark = api.nvim_get_mark('F', {})
       -- Compare the path tail only
-      assert(string.find(mark[4], 'mybuf$'))
+      matches('mybuf$', mark[4])
       eq({ 2, 2, buf, mark[4] }, mark)
     end)
     it('validation', function()
@@ -3855,13 +3918,13 @@ describe('API', function()
           norm 4G
         ]])
         eq({
-          str = '││aabb 4 ',
+          str = '││bbaa 4 ',
           width = 9,
           highlights = {
             { group = 'CursorLineFold', start = 0 },
             { group = 'Normal', start = 6 },
-            { group = 'IncSearch', start = 6 },
-            { group = 'ErrorMsg', start = 8 },
+            { group = 'ErrorMsg', start = 6 },
+            { group = 'IncSearch', start = 8 },
             { group = 'Normal', start = 10 },
           },
         }, api.nvim_eval_statusline(
@@ -4953,4 +5016,218 @@ describe('API', function()
       eq(false, exec_lua('return _G.success'))
     end)
   end)
+
+  it('nvim__redraw', function()
+    local screen = Screen.new(60, 5)
+    screen:attach()
+    local win = api.nvim_get_current_win()
+    eq('at least one action required', pcall_err(api.nvim__redraw, {}))
+    eq('at least one action required', pcall_err(api.nvim__redraw, { buf = 0 }))
+    eq('at least one action required', pcall_err(api.nvim__redraw, { win = 0 }))
+    eq("cannot use both 'buf' and 'win'", pcall_err(api.nvim__redraw, { buf = 0, win = 0 }))
+    feed(':echo getchar()<CR>')
+    fn.setline(1, 'foobar')
+    command('vnew')
+    fn.setline(1, 'foobaz')
+    -- Can flush pending screen updates
+    api.nvim__redraw({ flush = true })
+    screen:expect({
+      grid = [[
+        foobaz                        │foobar                       |
+        {1:~                             }│{1:~                            }|*2
+        {3:[No Name] [+]                  }{2:[No Name] [+]                }|
+        ^:echo getchar()                                             |
+      ]],
+    })
+    -- Can update the grid cursor position #20793
+    api.nvim__redraw({ cursor = true })
+    screen:expect({
+      grid = [[
+        ^foobaz                        │foobar                       |
+        {1:~                             }│{1:~                            }|*2
+        {3:[No Name] [+]                  }{2:[No Name] [+]                }|
+        :echo getchar()                                             |
+      ]],
+    })
+    -- Also in non-current window
+    api.nvim__redraw({ cursor = true, win = win })
+    screen:expect({
+      grid = [[
+        foobaz                        │^foobar                       |
+        {1:~                             }│{1:~                            }|*2
+        {3:[No Name] [+]                  }{2:[No Name] [+]                }|
+        :echo getchar()                                             |
+      ]],
+    })
+    -- Can update the 'statusline' in a single window
+    api.nvim_set_option_value('statusline', 'statusline1', { win = 0 })
+    api.nvim_set_option_value('statusline', 'statusline2', { win = win })
+    api.nvim__redraw({ cursor = true, win = 0, statusline = true })
+    screen:expect({
+      grid = [[
+        ^foobaz                        │foobar                       |
+        {1:~                             }│{1:~                            }|*2
+        {3:statusline1                    }{2:[No Name] [+]                }|
+        :echo getchar()                                             |
+      ]],
+    })
+    api.nvim__redraw({ win = win, statusline = true })
+    screen:expect({
+      grid = [[
+        ^foobaz                        │foobar                       |
+        {1:~                             }│{1:~                            }|*2
+        {3:statusline1                    }{2:statusline2                  }|
+        :echo getchar()                                             |
+      ]],
+    })
+    -- Can update the 'statusline' in all windows
+    api.nvim_set_option_value('statusline', '', { win = win })
+    api.nvim_set_option_value('statusline', 'statusline3', {})
+    api.nvim__redraw({ statusline = true })
+    screen:expect({
+      grid = [[
+        ^foobaz                        │foobar                       |
+        {1:~                             }│{1:~                            }|*2
+        {3:statusline3                    }{2:statusline3                  }|
+        :echo getchar()                                             |
+      ]],
+    })
+    -- Can update the 'statuscolumn'
+    api.nvim_set_option_value('statuscolumn', 'statuscolumn', { win = win })
+    api.nvim__redraw({ statuscolumn = true })
+    screen:expect({
+      grid = [[
+        ^foobaz                        │{8:statuscolumn}foobar           |
+        {1:~                             }│{1:~                            }|*2
+        {3:statusline3                    }{2:statusline3                  }|
+        :echo getchar()                                             |
+      ]],
+    })
+    -- Can update the 'winbar'
+    api.nvim_set_option_value('winbar', 'winbar', { win = 0 })
+    api.nvim__redraw({ win = 0, winbar = true })
+    screen:expect({
+      grid = [[
+        {5:^winbar                        }│{8:statuscolumn}foobar           |
+        foobaz                        │{1:~                            }|
+        {1:~                             }│{1:~                            }|
+        {3:statusline3                    }{2:statusline3                  }|
+        :echo getchar()                                             |
+      ]],
+    })
+    -- Can update the 'tabline'
+    api.nvim_set_option_value('showtabline', 2, {})
+    api.nvim_set_option_value('tabline', 'tabline', {})
+    api.nvim__redraw({ tabline = true })
+    screen:expect({
+      grid = [[
+        {2:^tabline                                                     }|
+        {5:winbar                        }│{8:statuscolumn}foobar           |
+        foobaz                        │{1:~                            }|
+        {3:statusline3                    }{2:statusline3                  }|
+        :echo getchar()                                             |
+      ]],
+    })
+    -- Can update multiple status widgets
+    api.nvim_set_option_value('tabline', 'tabline2', {})
+    api.nvim_set_option_value('statusline', 'statusline4', {})
+    api.nvim__redraw({ statusline = true, tabline = true })
+    screen:expect({
+      grid = [[
+        {2:^tabline2                                                    }|
+        {5:winbar                        }│{8:statuscolumn}foobar           |
+        foobaz                        │{1:~                            }|
+        {3:statusline4                    }{2:statusline4                  }|
+        :echo getchar()                                             |
+      ]],
+    })
+    -- Can update all status widgets
+    api.nvim_set_option_value('tabline', 'tabline3', {})
+    api.nvim_set_option_value('statusline', 'statusline5', {})
+    api.nvim_set_option_value('statuscolumn', 'statuscolumn2', {})
+    api.nvim_set_option_value('winbar', 'winbar2', {})
+    api.nvim__redraw({ statuscolumn = true, statusline = true, tabline = true, winbar = true })
+    screen:expect({
+      grid = [[
+        {2:^tabline3                                                    }|
+        {5:winbar2                       }│{5:winbar2                      }|
+        {8:statuscolumn2}foobaz           │{8:statuscolumn}foobar           |
+        {3:statusline5                    }{2:statusline5                  }|
+        :echo getchar()                                             |
+      ]],
+    })
+    -- Can update status widget for a specific window
+    feed('<CR><CR>')
+    command('let g:status=0')
+    api.nvim_set_option_value('statusline', '%{%g:status%}', { win = 0 })
+    command('vsplit')
+    screen:expect({
+      grid = [[
+        {2:tabline3                                                    }|
+        {5:winbar2             }│{5:winbar2            }│{5:winbar2            }|
+        {8:statuscolumn2}^foobaz │{8:statuscolumn2}foobaz│{8:statuscolumn}foobar |
+        {3:0                    }{2:0                   statusline5        }|
+        13                                                          |
+      ]],
+    })
+    command('let g:status=1')
+    api.nvim__redraw({ win = 0, statusline = true })
+    screen:expect({
+      grid = [[
+        {2:tabline3                                                    }|
+        {5:winbar2             }│{5:winbar2            }│{5:winbar2            }|
+        {8:statuscolumn2}^foobaz │{8:statuscolumn2}foobaz│{8:statuscolumn}foobar |
+        {3:1                    }{2:0                   statusline5        }|
+        13                                                          |
+      ]],
+    })
+    -- Can update status widget for a specific buffer
+    command('let g:status=2')
+    api.nvim__redraw({ buf = 0, statusline = true })
+    screen:expect({
+      grid = [[
+        {2:tabline3                                                    }|
+        {5:winbar2             }│{5:winbar2            }│{5:winbar2            }|
+        {8:statuscolumn2}^foobaz │{8:statuscolumn2}foobaz│{8:statuscolumn}foobar |
+        {3:2                    }{2:2                   statusline5        }|
+        13                                                          |
+      ]],
+    })
+    -- valid = true does not draw any lines on its own
+    exec_lua([[
+      _G.lines = 0
+      ns = vim.api.nvim_create_namespace('')
+      vim.api.nvim_set_decoration_provider(ns, {
+        on_win = function()
+          if _G.do_win then
+            vim.api.nvim_buf_set_extmark(0, ns, 0, 0, { hl_group = 'IncSearch', end_col = 6 })
+          end
+        end,
+        on_line = function()
+          _G.lines = _G.lines + 1
+        end,
+      })
+    ]])
+    local lines = exec_lua('return lines')
+    api.nvim__redraw({ buf = 0, valid = true, flush = true })
+    eq(lines, exec_lua('return _G.lines'))
+    -- valid = false does
+    api.nvim__redraw({ buf = 0, valid = false, flush = true })
+    neq(lines, exec_lua('return _G.lines'))
+    -- valid = true does redraw lines if affected by on_win callback
+    exec_lua('_G.do_win = true')
+    api.nvim__redraw({ buf = 0, valid = true, flush = true })
+    screen:expect({
+      grid = [[
+        {2:tabline3                                                    }|
+        {5:winbar2             }│{5:winbar2            }│{5:winbar2            }|
+        {8:statuscolumn2}{2:^foobaz} │{8:statuscolumn2}{2:foobaz}│{8:statuscolumn}foobar |
+        {3:2                    }{2:2                   statusline5        }|
+        13                                                          |
+      ]],
+    })
+    -- takes buffer line count from correct buffer with "win" and {0, -1} "range"
+    api.nvim__redraw({ win = 0, range = { 0, -1 } })
+    n.assert_alive()
+  end)
 end)
diff --git a/test/functional/api/window_spec.lua b/test/functional/api/window_spec.lua
index 097a546ef2..15b9b0945c 100644
--- a/test/functional/api/window_spec.lua
+++ b/test/functional/api/window_spec.lua
@@ -1,27 +1,29 @@
-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 clear, curbuf, curbuf_contents, curwin, eq, neq, matches, ok, feed, insert, eval =
-  helpers.clear,
-  helpers.api.nvim_get_current_buf,
-  helpers.curbuf_contents,
-  helpers.api.nvim_get_current_win,
-  helpers.eq,
-  helpers.neq,
-  helpers.matches,
-  helpers.ok,
-  helpers.feed,
-  helpers.insert,
-  helpers.eval
-local poke_eventloop = helpers.poke_eventloop
-local exec = helpers.exec
-local exec_lua = helpers.exec_lua
-local fn = helpers.fn
-local request = helpers.request
+  n.clear,
+  n.api.nvim_get_current_buf,
+  n.curbuf_contents,
+  n.api.nvim_get_current_win,
+  t.eq,
+  t.neq,
+  t.matches,
+  t.ok,
+  n.feed,
+  n.insert,
+  n.eval
+local poke_eventloop = n.poke_eventloop
+local exec = n.exec
+local exec_lua = n.exec_lua
+local fn = n.fn
+local request = n.request
 local NIL = vim.NIL
-local api = helpers.api
-local command = helpers.command
-local pcall_err = helpers.pcall_err
-local assert_alive = helpers.assert_alive
+local api = n.api
+local command = n.command
+local pcall_err = t.pcall_err
+local assert_alive = n.assert_alive
 
 describe('API/win', function()
   before_each(clear)
@@ -111,6 +113,44 @@ describe('API/win', function()
       api.nvim_win_set_buf(new_win, next_buf)
       eq(next_buf, api.nvim_win_get_buf(new_win))
     end)
+
+    describe("with 'autochdir'", function()
+      local topdir
+      local otherbuf
+      local oldwin
+      local newwin
+
+      before_each(function()
+        command('set shellslash')
+        topdir = fn.getcwd()
+        t.mkdir(topdir .. '/Xacd')
+        t.mkdir(topdir .. '/Xacd/foo')
+        otherbuf = api.nvim_create_buf(false, true)
+        api.nvim_buf_set_name(otherbuf, topdir .. '/Xacd/baz.txt')
+
+        command('set autochdir')
+        command('edit Xacd/foo/bar.txt')
+        eq(topdir .. '/Xacd/foo', fn.getcwd())
+
+        oldwin = api.nvim_get_current_win()
+        command('vsplit')
+        newwin = api.nvim_get_current_win()
+      end)
+
+      after_each(function()
+        n.rmdir(topdir .. '/Xacd')
+      end)
+
+      it('does not change cwd with non-current window', function()
+        api.nvim_win_set_buf(oldwin, otherbuf)
+        eq(topdir .. '/Xacd/foo', fn.getcwd())
+      end)
+
+      it('changes cwd with current window', function()
+        api.nvim_win_set_buf(newwin, otherbuf)
+        eq(topdir .. '/Xacd', fn.getcwd())
+      end)
+    end)
   end)
 
   describe('{get,set}_cursor', function()
@@ -1147,27 +1187,6 @@ describe('API/win', function()
   end)
 
   describe('open_win', function()
-    it('noautocmd option works', function()
-      command('autocmd BufEnter,BufLeave,BufWinEnter * let g:fired = 1')
-      api.nvim_open_win(api.nvim_create_buf(true, true), true, {
-        relative = 'win',
-        row = 3,
-        col = 3,
-        width = 12,
-        height = 3,
-        noautocmd = true,
-      })
-      eq(0, fn.exists('g:fired'))
-      api.nvim_open_win(api.nvim_create_buf(true, true), true, {
-        relative = 'win',
-        row = 3,
-        col = 3,
-        width = 12,
-        height = 3,
-      })
-      eq(1, fn.exists('g:fired'))
-    end)
-
     it('disallowed in cmdwin if enter=true or buf=cmdwin_buf', function()
       local new_buf = api.nvim_create_buf(true, true)
       feed('q:')
@@ -1233,81 +1252,151 @@ describe('API/win', function()
       eq(wins_before, api.nvim_list_wins())
     end)
 
-    it('creates a split window', function()
-      local win = api.nvim_open_win(0, true, {
-        vertical = false,
-      })
-      eq('', api.nvim_win_get_config(win).relative)
+    describe('creates a split window above', function()
+      local function test_open_win_split_above(key, val)
+        local initial_win = api.nvim_get_current_win()
+        local win = api.nvim_open_win(0, true, {
+          [key] = val,
+          height = 10,
+        })
+        eq('', api.nvim_win_get_config(win).relative)
+        eq(10, api.nvim_win_get_height(win))
+        local layout = fn.winlayout()
+        eq({
+          'col',
+          {
+            { 'leaf', win },
+            { 'leaf', initial_win },
+          },
+        }, layout)
+      end
+
+      it("with split = 'above'", function()
+        test_open_win_split_above('split', 'above')
+      end)
+
+      it("with vertical = false and 'nosplitbelow'", function()
+        api.nvim_set_option_value('splitbelow', false, {})
+        test_open_win_split_above('vertical', false)
+      end)
     end)
 
-    it('creates split windows in the correct direction', function()
-      local initial_win = api.nvim_get_current_win()
-      local win = api.nvim_open_win(0, true, {
-        vertical = true,
-      })
-      eq('', api.nvim_win_get_config(win).relative)
+    describe('creates a split window below', function()
+      local function test_open_win_split_below(key, val)
+        local initial_win = api.nvim_get_current_win()
+        local win = api.nvim_open_win(0, true, {
+          [key] = val,
+          height = 15,
+        })
+        eq('', api.nvim_win_get_config(win).relative)
+        eq(15, api.nvim_win_get_height(win))
+        local layout = fn.winlayout()
+        eq({
+          'col',
+          {
+            { 'leaf', initial_win },
+            { 'leaf', win },
+          },
+        }, layout)
+      end
 
-      local layout = fn.winlayout()
+      it("with split = 'below'", function()
+        test_open_win_split_below('split', 'below')
+      end)
 
-      eq({
-        'row',
-        {
-          { 'leaf', win },
-          { 'leaf', initial_win },
-        },
-      }, layout)
+      it("with vertical = false and 'splitbelow'", function()
+        api.nvim_set_option_value('splitbelow', true, {})
+        test_open_win_split_below('vertical', false)
+      end)
     end)
 
-    it("respects the 'split' option", function()
-      local initial_win = api.nvim_get_current_win()
-      local win = api.nvim_open_win(0, true, {
-        split = 'below',
-      })
-      eq('', api.nvim_win_get_config(win).relative)
+    describe('creates a split window to the left', function()
+      local function test_open_win_split_left(key, val)
+        local initial_win = api.nvim_get_current_win()
+        local win = api.nvim_open_win(0, true, {
+          [key] = val,
+          width = 25,
+        })
+        eq('', api.nvim_win_get_config(win).relative)
+        eq(25, api.nvim_win_get_width(win))
+        local layout = fn.winlayout()
+        eq({
+          'row',
+          {
+            { 'leaf', win },
+            { 'leaf', initial_win },
+          },
+        }, layout)
+      end
 
-      local layout = fn.winlayout()
+      it("with split = 'left'", function()
+        test_open_win_split_left('split', 'left')
+      end)
 
-      eq({
-        'col',
-        {
-          { 'leaf', initial_win },
-          { 'leaf', win },
-        },
-      }, layout)
+      it("with vertical = true and 'nosplitright'", function()
+        api.nvim_set_option_value('splitright', false, {})
+        test_open_win_split_left('vertical', true)
+      end)
     end)
 
-    it(
-      "doesn't change tp_curwin when splitting window in non-current tab with enter=false",
-      function()
-        local tab1 = api.nvim_get_current_tabpage()
-        local tab1_win = api.nvim_get_current_win()
+    describe('creates a split window to the right', function()
+      local function test_open_win_split_right(key, val)
+        local initial_win = api.nvim_get_current_win()
+        local win = api.nvim_open_win(0, true, {
+          [key] = val,
+          width = 30,
+        })
+        eq('', api.nvim_win_get_config(win).relative)
+        eq(30, api.nvim_win_get_width(win))
+        local layout = fn.winlayout()
+        eq({
+          'row',
+          {
+            { 'leaf', initial_win },
+            { 'leaf', win },
+          },
+        }, layout)
+      end
+
+      it("with split = 'right'", function()
+        test_open_win_split_right('split', 'right')
+      end)
 
-        helpers.command('tabnew')
-        local tab2 = api.nvim_get_current_tabpage()
-        local tab2_win = api.nvim_get_current_win()
+      it("with vertical = true and 'splitright'", function()
+        api.nvim_set_option_value('splitright', true, {})
+        test_open_win_split_right('vertical', true)
+      end)
+    end)
 
-        eq({ tab1_win, tab2_win }, api.nvim_list_wins())
-        eq({ tab1, tab2 }, api.nvim_list_tabpages())
+    it("doesn't change tp_curwin when splitting window in another tab with enter=false", function()
+      local tab1 = api.nvim_get_current_tabpage()
+      local tab1_win = api.nvim_get_current_win()
 
-        api.nvim_set_current_tabpage(tab1)
-        eq(tab1_win, api.nvim_get_current_win())
+      n.command('tabnew')
+      local tab2 = api.nvim_get_current_tabpage()
+      local tab2_win = api.nvim_get_current_win()
 
-        local tab2_prevwin = fn.tabpagewinnr(tab2, '#')
+      eq({ tab1_win, tab2_win }, api.nvim_list_wins())
+      eq({ tab1, tab2 }, api.nvim_list_tabpages())
 
-        -- split in tab2 whine in tab2, with enter = false
-        local tab2_win2 = api.nvim_open_win(api.nvim_create_buf(false, true), false, {
-          win = tab2_win,
-          split = 'right',
-        })
-        eq(tab1_win, api.nvim_get_current_win()) -- we should still be in the first tp
-        eq(tab1_win, api.nvim_tabpage_get_win(tab1))
+      api.nvim_set_current_tabpage(tab1)
+      eq(tab1_win, api.nvim_get_current_win())
 
-        eq(tab2_win, api.nvim_tabpage_get_win(tab2)) -- tab2's tp_curwin should not have changed
-        eq(tab2_prevwin, fn.tabpagewinnr(tab2, '#')) -- tab2's tp_prevwin should not have changed
-        eq({ tab1_win, tab2_win, tab2_win2 }, api.nvim_list_wins())
-        eq({ tab2_win, tab2_win2 }, api.nvim_tabpage_list_wins(tab2))
-      end
-    )
+      local tab2_prevwin = fn.tabpagewinnr(tab2, '#')
+
+      -- split in tab2 whine in tab2, with enter = false
+      local tab2_win2 = api.nvim_open_win(api.nvim_create_buf(false, true), false, {
+        win = tab2_win,
+        split = 'right',
+      })
+      eq(tab1_win, api.nvim_get_current_win()) -- we should still be in the first tp
+      eq(tab1_win, api.nvim_tabpage_get_win(tab1))
+
+      eq(tab2_win, api.nvim_tabpage_get_win(tab2)) -- tab2's tp_curwin should not have changed
+      eq(tab2_prevwin, fn.tabpagewinnr(tab2, '#')) -- tab2's tp_prevwin should not have changed
+      eq({ tab1_win, tab2_win, tab2_win2 }, api.nvim_list_wins())
+      eq({ tab2_win, tab2_win2 }, api.nvim_tabpage_list_wins(tab2))
+    end)
 
     it('creates splits in the correct location', function()
       local first_win = api.nvim_get_current_win()
@@ -1364,6 +1453,400 @@ describe('API/win', function()
         },
       }, layout)
     end)
+
+    it('opens floating windows in other tabpages', function()
+      local first_win = api.nvim_get_current_win()
+      local first_tab = api.nvim_get_current_tabpage()
+
+      command('tabnew')
+      local new_tab = api.nvim_get_current_tabpage()
+      local win = api.nvim_open_win(0, false, {
+        relative = 'win',
+        win = first_win,
+        width = 5,
+        height = 5,
+        row = 1,
+        col = 1,
+      })
+      eq(api.nvim_win_get_tabpage(win), first_tab)
+      eq(api.nvim_get_current_tabpage(), new_tab)
+    end)
+
+    it('switches to new windows in non-current tabpages when enter=true', function()
+      local first_win = api.nvim_get_current_win()
+      local first_tab = api.nvim_get_current_tabpage()
+      command('tabnew')
+      local win = api.nvim_open_win(0, true, {
+        relative = 'win',
+        win = first_win,
+        width = 5,
+        height = 5,
+        row = 1,
+        col = 1,
+      })
+      eq(api.nvim_win_get_tabpage(win), first_tab)
+      eq(api.nvim_get_current_tabpage(), first_tab)
+    end)
+
+    local function setup_tabbed_autocmd_test()
+      local info = {}
+      info.orig_buf = api.nvim_get_current_buf()
+      info.other_buf = api.nvim_create_buf(true, true)
+      info.tab1_curwin = api.nvim_get_current_win()
+      info.tab1 = api.nvim_get_current_tabpage()
+      command('tab split | split')
+      info.tab2_curwin = api.nvim_get_current_win()
+      info.tab2 = api.nvim_get_current_tabpage()
+      exec([=[
+        tabfirst
+        let result = []
+        autocmd TabEnter * let result += [["TabEnter", nvim_get_current_tabpage()]]
+        autocmd TabLeave * let result += [["TabLeave", nvim_get_current_tabpage()]]
+        autocmd WinEnter * let result += [["WinEnter", win_getid()]]
+        autocmd WinLeave * let result += [["WinLeave", win_getid()]]
+        autocmd WinNew * let result += [["WinNew", win_getid()]]
+        autocmd WinClosed * let result += [["WinClosed", str2nr(expand("<afile>"))]]
+        autocmd BufEnter * let result += [["BufEnter", win_getid(), bufnr()]]
+        autocmd BufLeave * let result += [["BufLeave", win_getid(), bufnr()]]
+        autocmd BufWinEnter * let result += [["BufWinEnter", win_getid(), bufnr()]]
+        autocmd BufWinLeave * let result += [["BufWinLeave", win_getid(), bufnr()]]
+      ]=])
+      return info
+    end
+
+    it('noautocmd option works', function()
+      local info = setup_tabbed_autocmd_test()
+
+      api.nvim_open_win(
+        info.other_buf,
+        true,
+        { split = 'left', win = info.tab2_curwin, noautocmd = true }
+      )
+      eq({}, eval('result'))
+
+      api.nvim_open_win(
+        info.orig_buf,
+        true,
+        { relative = 'editor', row = 0, col = 0, width = 10, height = 10, noautocmd = true }
+      )
+      eq({}, eval('result'))
+    end)
+
+    it('fires expected autocmds when creating splits without entering', function()
+      local info = setup_tabbed_autocmd_test()
+
+      -- For these, don't want BufWinEnter if visiting the same buffer, like :{s}buffer.
+      -- Same tabpage, same buffer.
+      local new_win = api.nvim_open_win(0, false, { split = 'left', win = info.tab1_curwin })
+      eq({
+        { 'WinNew', new_win },
+      }, eval('result'))
+      eq(info.tab1_curwin, api.nvim_get_current_win())
+
+      -- Other tabpage, same buffer.
+      command('let result = []')
+      new_win = api.nvim_open_win(0, false, { split = 'left', win = info.tab2_curwin })
+      eq({
+        { 'WinNew', new_win },
+      }, eval('result'))
+      eq(info.tab1_curwin, api.nvim_get_current_win())
+
+      -- Same tabpage, other buffer.
+      command('let result = []')
+      new_win = api.nvim_open_win(info.other_buf, false, { split = 'left', win = info.tab1_curwin })
+      eq({
+        { 'WinNew', new_win },
+        { 'BufWinEnter', new_win, info.other_buf },
+      }, eval('result'))
+      eq(info.tab1_curwin, api.nvim_get_current_win())
+
+      -- Other tabpage, other buffer.
+      command('let result = []')
+      new_win = api.nvim_open_win(info.other_buf, false, { split = 'left', win = info.tab2_curwin })
+      eq({
+        { 'WinNew', new_win },
+        { 'BufWinEnter', new_win, info.other_buf },
+      }, eval('result'))
+      eq(info.tab1_curwin, api.nvim_get_current_win())
+    end)
+
+    it('fires expected autocmds when creating and entering splits', function()
+      local info = setup_tabbed_autocmd_test()
+
+      -- Same tabpage, same buffer.
+      local new_win = api.nvim_open_win(0, true, { split = 'left', win = info.tab1_curwin })
+      eq({
+        { 'WinNew', new_win },
+        { 'WinLeave', info.tab1_curwin },
+        { 'WinEnter', new_win },
+      }, eval('result'))
+
+      -- Same tabpage, other buffer.
+      api.nvim_set_current_win(info.tab1_curwin)
+      command('let result = []')
+      new_win = api.nvim_open_win(info.other_buf, true, { split = 'left', win = info.tab1_curwin })
+      eq({
+        { 'WinNew', new_win },
+        { 'WinLeave', info.tab1_curwin },
+        { 'WinEnter', new_win },
+        { 'BufLeave', new_win, info.orig_buf },
+        { 'BufEnter', new_win, info.other_buf },
+        { 'BufWinEnter', new_win, info.other_buf },
+      }, eval('result'))
+
+      -- For these, the other tabpage's prevwin and curwin will change like we switched from its old
+      -- curwin to the new window, so the extra events near TabEnter reflect that.
+      -- Other tabpage, same buffer.
+      api.nvim_set_current_win(info.tab1_curwin)
+      command('let result = []')
+      new_win = api.nvim_open_win(0, true, { split = 'left', win = info.tab2_curwin })
+      eq({
+        { 'WinNew', new_win },
+        { 'WinLeave', info.tab1_curwin },
+        { 'TabLeave', info.tab1 },
+
+        { 'WinEnter', info.tab2_curwin },
+        { 'TabEnter', info.tab2 },
+        { 'WinLeave', info.tab2_curwin },
+        { 'WinEnter', new_win },
+      }, eval('result'))
+
+      -- Other tabpage, other buffer.
+      api.nvim_set_current_win(info.tab2_curwin)
+      api.nvim_set_current_win(info.tab1_curwin)
+      command('let result = []')
+      new_win = api.nvim_open_win(info.other_buf, true, { split = 'left', win = info.tab2_curwin })
+      eq({
+        { 'WinNew', new_win },
+        { 'WinLeave', info.tab1_curwin },
+        { 'TabLeave', info.tab1 },
+
+        { 'WinEnter', info.tab2_curwin },
+        { 'TabEnter', info.tab2 },
+        { 'WinLeave', info.tab2_curwin },
+        { 'WinEnter', new_win },
+
+        { 'BufLeave', new_win, info.orig_buf },
+        { 'BufEnter', new_win, info.other_buf },
+        { 'BufWinEnter', new_win, info.other_buf },
+      }, eval('result'))
+
+      -- Other tabpage, other buffer; but other tabpage's curwin has a new buffer active.
+      api.nvim_set_current_win(info.tab2_curwin)
+      local new_buf = api.nvim_create_buf(true, true)
+      api.nvim_set_current_buf(new_buf)
+      api.nvim_set_current_win(info.tab1_curwin)
+      command('let result = []')
+      new_win = api.nvim_open_win(info.other_buf, true, { split = 'left', win = info.tab2_curwin })
+      eq({
+        { 'WinNew', new_win },
+        { 'BufLeave', info.tab1_curwin, info.orig_buf },
+        { 'WinLeave', info.tab1_curwin },
+        { 'TabLeave', info.tab1 },
+
+        { 'WinEnter', info.tab2_curwin },
+        { 'TabEnter', info.tab2 },
+        { 'BufEnter', info.tab2_curwin, new_buf },
+        { 'WinLeave', info.tab2_curwin },
+        { 'WinEnter', new_win },
+        { 'BufLeave', new_win, new_buf },
+        { 'BufEnter', new_win, info.other_buf },
+        { 'BufWinEnter', new_win, info.other_buf },
+      }, eval('result'))
+    end)
+
+    it('OK when new window is moved to other tabpage by autocommands', function()
+      -- Use nvim_win_set_config in the autocommands, as other methods of moving a window to a
+      -- different tabpage (e.g: wincmd T) actually creates a new window.
+      local tab0 = api.nvim_get_current_tabpage()
+      local tab0_win = api.nvim_get_current_win()
+      command('tabnew')
+      local new_buf = api.nvim_create_buf(true, true)
+      local tab1 = api.nvim_get_current_tabpage()
+      local tab1_parent = api.nvim_get_current_win()
+      command(
+        'tabfirst | autocmd WinNew * ++once call nvim_win_set_config(0, #{split: "left", win: '
+          .. tab1_parent
+          .. '})'
+      )
+      local new_win = api.nvim_open_win(new_buf, true, { split = 'left' })
+      eq(tab1, api.nvim_get_current_tabpage())
+      eq(new_win, api.nvim_get_current_win())
+      eq(new_buf, api.nvim_get_current_buf())
+
+      -- nvim_win_set_config called after entering. It doesn't follow a curwin that is moved to a
+      -- different tabpage, but instead moves to the win filling the space, which is tab0_win.
+      command(
+        'tabfirst | autocmd WinEnter * ++once call nvim_win_set_config(0, #{split: "left", win: '
+          .. tab1_parent
+          .. '})'
+      )
+      new_win = api.nvim_open_win(new_buf, true, { split = 'left' })
+      eq(tab0, api.nvim_get_current_tabpage())
+      eq(tab0_win, api.nvim_get_current_win())
+      eq(tab1, api.nvim_win_get_tabpage(new_win))
+      eq(new_buf, api.nvim_win_get_buf(new_win))
+
+      command(
+        'tabfirst | autocmd BufEnter * ++once call nvim_win_set_config(0, #{split: "left", win: '
+          .. tab1_parent
+          .. '})'
+      )
+      new_win = api.nvim_open_win(new_buf, true, { split = 'left' })
+      eq(tab0, api.nvim_get_current_tabpage())
+      eq(tab0_win, api.nvim_get_current_win())
+      eq(tab1, api.nvim_win_get_tabpage(new_win))
+      eq(new_buf, api.nvim_win_get_buf(new_win))
+    end)
+
+    it('does not fire BufWinEnter if win_set_buf fails', function()
+      exec([[
+        set nohidden modified
+        autocmd WinNew * ++once only!
+        let fired = v:false
+        autocmd BufWinEnter * ++once let fired = v:true
+      ]])
+      eq(
+        'Failed to set buffer 2',
+        pcall_err(api.nvim_open_win, api.nvim_create_buf(true, true), false, { split = 'left' })
+      )
+      eq(false, eval('fired'))
+    end)
+
+    it('fires Buf* autocommands when `!enter` if window is entered via autocommands', function()
+      exec([[
+        autocmd WinNew * ++once only!
+        let fired = v:false
+        autocmd BufEnter * ++once let fired = v:true
+      ]])
+      api.nvim_open_win(api.nvim_create_buf(true, true), false, { split = 'left' })
+      eq(true, eval('fired'))
+    end)
+
+    it('no heap-use-after-free if target buffer deleted by autocommands', function()
+      local cur_buf = api.nvim_get_current_buf()
+      local new_buf = api.nvim_create_buf(true, true)
+      command('autocmd WinNew * ++once call nvim_buf_delete(' .. new_buf .. ', #{force: 1})')
+      api.nvim_open_win(new_buf, true, { split = 'left' })
+      eq(cur_buf, api.nvim_get_current_buf())
+    end)
+
+    it('checks if splitting disallowed', function()
+      command('split | autocmd WinEnter * ++once call nvim_open_win(0, 0, #{split: "right"})')
+      matches("E242: Can't split a window while closing another$", pcall_err(command, 'quit'))
+
+      command('only | autocmd BufHidden * ++once call nvim_open_win(0, 0, #{split: "left"})')
+      matches(
+        'E1159: Cannot split a window when closing the buffer$',
+        pcall_err(command, 'new | quit')
+      )
+
+      local w = api.nvim_get_current_win()
+      command(
+        'only | new | autocmd BufHidden * ++once call nvim_open_win(0, 0, #{split: "left", win: '
+          .. w
+          .. '})'
+      )
+      matches(
+        'E1159: Cannot split a window when closing the buffer$',
+        pcall_err(api.nvim_win_close, w, true)
+      )
+
+      -- OK when using window to different buffer than `win`s.
+      w = api.nvim_get_current_win()
+      command(
+        'only | autocmd BufHidden * ++once call nvim_open_win(0, 0, #{split: "left", win: '
+          .. w
+          .. '})'
+      )
+      command('new | quit')
+    end)
+
+    it('restores last known cursor position if BufWinEnter did not move it', function()
+      -- This test mostly exists to ensure BufWinEnter is executed before enter_buffer's epilogue.
+      local buf = api.nvim_get_current_buf()
+      insert([[
+        foo
+        bar baz .etc
+        i love autocommand bugs!
+        supercalifragilisticexpialidocious
+        marvim is actually a human
+        llanfairpwllgwyngyllgogerychwyrndrobwllllantysiliogogogoch
+      ]])
+      api.nvim_win_set_cursor(0, { 5, 2 })
+      command('set nostartofline | enew')
+      local new_win = api.nvim_open_win(buf, false, { split = 'left' })
+      eq({ 5, 2 }, api.nvim_win_get_cursor(new_win))
+
+      exec([[
+        only!
+        autocmd BufWinEnter * ++once normal! j6l
+      ]])
+      new_win = api.nvim_open_win(buf, false, { split = 'left' })
+      eq({ 2, 6 }, api.nvim_win_get_cursor(new_win))
+    end)
+
+    it('does not block all win_set_buf autocommands if !enter and !noautocmd', function()
+      local new_buf = fn.bufadd('foobarbaz')
+      exec([[
+        let triggered = ""
+        autocmd BufReadCmd * ++once let triggered = bufname()
+      ]])
+      api.nvim_open_win(new_buf, false, { split = 'left' })
+      eq('foobarbaz', eval('triggered'))
+    end)
+
+    it('sets error when no room', function()
+      matches('E36: Not enough room$', pcall_err(command, 'execute "split|"->repeat(&lines)'))
+      matches(
+        'E36: Not enough room$',
+        pcall_err(api.nvim_open_win, 0, true, { split = 'above', win = 0 })
+      )
+      matches(
+        'E36: Not enough room$',
+        pcall_err(api.nvim_open_win, 0, true, { split = 'below', win = 0 })
+      )
+    end)
+
+    describe("with 'autochdir'", function()
+      local topdir
+      local otherbuf
+
+      before_each(function()
+        command('set shellslash')
+        topdir = fn.getcwd()
+        t.mkdir(topdir .. '/Xacd')
+        t.mkdir(topdir .. '/Xacd/foo')
+        otherbuf = api.nvim_create_buf(false, true)
+        api.nvim_buf_set_name(otherbuf, topdir .. '/Xacd/baz.txt')
+
+        command('set autochdir')
+        command('edit Xacd/foo/bar.txt')
+        eq(topdir .. '/Xacd/foo', fn.getcwd())
+      end)
+
+      after_each(function()
+        n.rmdir(topdir .. '/Xacd')
+      end)
+
+      it('does not change cwd with enter=false #15280', function()
+        api.nvim_open_win(
+          otherbuf,
+          false,
+          { relative = 'editor', height = 5, width = 5, row = 5, col = 5 }
+        )
+        eq(topdir .. '/Xacd/foo', fn.getcwd())
+      end)
+
+      it('changes cwd with enter=true', function()
+        api.nvim_open_win(
+          otherbuf,
+          true,
+          { relative = 'editor', height = 5, width = 5, row = 5, col = 5 }
+        )
+        eq(topdir .. '/Xacd', fn.getcwd())
+      end)
+    end)
   end)
 
   describe('set_config', function()
@@ -1471,6 +1954,15 @@ describe('API/win', function()
       config = api.nvim_win_get_config(win)
       eq('', config.relative)
       eq('below', config.split)
+
+      eq(
+        "non-float with 'win' requires at least 'split' or 'vertical'",
+        pcall_err(api.nvim_win_set_config, 0, { win = 0 })
+      )
+      eq(
+        "non-float with 'win' requires at least 'split' or 'vertical'",
+        pcall_err(api.nvim_win_set_config, 0, { win = 0, relative = '' })
+      )
     end)
 
     it('creates top-level splits', function()
@@ -1663,6 +2155,474 @@ describe('API/win', function()
         },
       }, fn.winlayout())
     end)
+
+    it('closing new curwin when moving window to other tabpage works', function()
+      command('split | tabnew')
+      local t2_win = api.nvim_get_current_win()
+      command('tabfirst | autocmd WinEnter * ++once quit')
+      local t1_move_win = api.nvim_get_current_win()
+      -- win_set_config fails to switch away from "t1_move_win" because the WinEnter autocmd that
+      -- closed the window we're switched to returns us to "t1_move_win", as it filled the space.
+      eq(
+        'Failed to switch away from window ' .. t1_move_win,
+        pcall_err(api.nvim_win_set_config, t1_move_win, { win = t2_win, split = 'left' })
+      )
+      eq(t1_move_win, api.nvim_get_current_win())
+
+      command('split | split | autocmd WinEnter * ++once quit')
+      t1_move_win = api.nvim_get_current_win()
+      -- In this case, we closed the window that we got switched to, but doing so didn't switch us
+      -- back to "t1_move_win", which is fine.
+      api.nvim_win_set_config(t1_move_win, { win = t2_win, split = 'left' })
+      neq(t1_move_win, api.nvim_get_current_win())
+    end)
+
+    it('messing with "win" or "parent" when moving "win" to other tabpage', function()
+      command('split | tabnew')
+      local t2 = api.nvim_get_current_tabpage()
+      local t2_win1 = api.nvim_get_current_win()
+      command('split')
+      local t2_win2 = api.nvim_get_current_win()
+      command('split')
+      local t2_win3 = api.nvim_get_current_win()
+
+      command('tabfirst | autocmd WinEnter * ++once call nvim_win_close(' .. t2_win1 .. ', 1)')
+      local cur_win = api.nvim_get_current_win()
+      eq(
+        'Windows to split were closed',
+        pcall_err(api.nvim_win_set_config, 0, { win = t2_win1, split = 'left' })
+      )
+      eq(cur_win, api.nvim_get_current_win())
+
+      command('split | autocmd WinLeave * ++once quit!')
+      cur_win = api.nvim_get_current_win()
+      eq(
+        'Windows to split were closed',
+        pcall_err(api.nvim_win_set_config, 0, { win = t2_win2, split = 'left' })
+      )
+      neq(cur_win, api.nvim_get_current_win())
+
+      exec([[
+        split
+        autocmd WinLeave * ++once
+              \ call nvim_win_set_config(0, #{relative:'editor', row:0, col:0, width:5, height:5})
+      ]])
+      cur_win = api.nvim_get_current_win()
+      eq(
+        'Floating state of windows to split changed',
+        pcall_err(api.nvim_win_set_config, 0, { win = t2_win3, split = 'left' })
+      )
+      eq('editor', api.nvim_win_get_config(0).relative)
+      eq(cur_win, api.nvim_get_current_win())
+
+      command('autocmd WinLeave * ++once wincmd J')
+      cur_win = api.nvim_get_current_win()
+      eq(
+        'Floating state of windows to split changed',
+        pcall_err(api.nvim_win_set_config, 0, { win = t2_win3, split = 'left' })
+      )
+      eq('', api.nvim_win_get_config(0).relative)
+      eq(cur_win, api.nvim_get_current_win())
+
+      -- Try to make "parent" floating. This should give the same error as before, but because
+      -- changing a split from another tabpage into a float isn't supported yet, check for that
+      -- error instead for now.
+      -- Use ":silent!" to avoid the one second delay from printing the error message.
+      exec(([[
+        autocmd WinLeave * ++once silent!
+              \ call nvim_win_set_config(%d, #{relative:'editor', row:0, col:0, width:5, height:5})
+      ]]):format(t2_win3))
+      cur_win = api.nvim_get_current_win()
+      api.nvim_win_set_config(0, { win = t2_win3, split = 'left' })
+      matches(
+        'Cannot change window from different tabpage into float$',
+        api.nvim_get_vvar('errmsg')
+      )
+      -- The error doesn't abort moving the window (or maybe it should, if that's wanted?)
+      neq(cur_win, api.nvim_get_current_win())
+      eq(t2, api.nvim_win_get_tabpage(cur_win))
+    end)
+
+    it('expected autocmds when moving window to other tabpage', function()
+      local new_curwin = api.nvim_get_current_win()
+      command('split')
+      local win = api.nvim_get_current_win()
+      command('tabnew')
+      local parent = api.nvim_get_current_win()
+      exec([[
+        tabfirst
+        let result = []
+        autocmd WinEnter * let result += ["Enter", win_getid()]
+        autocmd WinLeave * let result += ["Leave", win_getid()]
+        autocmd WinNew * let result += ["New", win_getid()]
+      ]])
+      api.nvim_win_set_config(0, { win = parent, split = 'left' })
+      -- Shouldn't see WinNew, as we're not creating any new windows, just moving existing ones.
+      eq({ 'Leave', win, 'Enter', new_curwin }, eval('result'))
+    end)
+
+    it('no autocmds when moving window within same tabpage', function()
+      local parent = api.nvim_get_current_win()
+      exec([[
+        split
+        let result = []
+        autocmd WinEnter * let result += ["Enter", win_getid()]
+        autocmd WinLeave * let result += ["Leave", win_getid()]
+        autocmd WinNew * let result += ["New", win_getid()]
+      ]])
+      api.nvim_win_set_config(0, { win = parent, split = 'left' })
+      -- Shouldn't see any of those events, as we remain in the same window.
+      eq({}, eval('result'))
+    end)
+
+    it('checks if splitting disallowed', function()
+      command('split | autocmd WinEnter * ++once call nvim_win_set_config(0, #{split: "right"})')
+      matches("E242: Can't split a window while closing another$", pcall_err(command, 'quit'))
+
+      command('autocmd BufHidden * ++once call nvim_win_set_config(0, #{split: "left"})')
+      matches(
+        'E1159: Cannot split a window when closing the buffer$',
+        pcall_err(command, 'new | quit')
+      )
+
+      -- OK when using window to different buffer.
+      local w = api.nvim_get_current_win()
+      command('autocmd BufHidden * ++once call nvim_win_set_config(' .. w .. ', #{split: "left"})')
+      command('new | quit')
+    end)
+
+    --- Returns a function to get information about the window layout, sizes and positions of a
+    --- tabpage.
+    local function define_tp_info_function()
+      exec_lua([[
+        function tp_info(tp)
+          return {
+            layout = vim.fn.winlayout(vim.api.nvim_tabpage_get_number(tp)),
+            pos_sizes = vim.tbl_map(
+              function(w)
+                local pos = vim.fn.win_screenpos(w)
+                return {
+                  row = pos[1],
+                  col = pos[2],
+                  width = vim.fn.winwidth(w),
+                  height = vim.fn.winheight(w)
+                }
+              end,
+              vim.api.nvim_tabpage_list_wins(tp)
+            )
+          }
+        end
+      ]])
+
+      return function(tp)
+        return exec_lua('return tp_info(...)', tp)
+      end
+    end
+
+    it('attempt to move window with no room', function()
+      -- Fill the 2nd tabpage full of windows until we run out of room.
+      -- Use &laststatus=0 to ensure restoring missing statuslines doesn't affect things.
+      command('set laststatus=0 | tabnew')
+      matches('E36: Not enough room$', pcall_err(command, 'execute "split|"->repeat(&lines)'))
+      command('vsplit | wincmd | | wincmd p')
+      local t2 = api.nvim_get_current_tabpage()
+      local t2_cur_win = api.nvim_get_current_win()
+      local t2_top_split = fn.win_getid(1)
+      local t2_bot_split = fn.win_getid(fn.winnr('$'))
+      local t2_float = api.nvim_open_win(
+        0,
+        false,
+        { relative = 'editor', row = 0, col = 0, width = 10, height = 10 }
+      )
+      local t2_float_config = api.nvim_win_get_config(t2_float)
+      local tp_info = define_tp_info_function()
+      local t2_info = tp_info(t2)
+      matches(
+        'E36: Not enough room$',
+        pcall_err(api.nvim_win_set_config, 0, { win = t2_top_split, split = 'above' })
+      )
+      matches(
+        'E36: Not enough room$',
+        pcall_err(api.nvim_win_set_config, 0, { win = t2_top_split, split = 'below' })
+      )
+      matches(
+        'E36: Not enough room$',
+        pcall_err(api.nvim_win_set_config, 0, { win = t2_bot_split, split = 'above' })
+      )
+      matches(
+        'E36: Not enough room$',
+        pcall_err(api.nvim_win_set_config, 0, { win = t2_bot_split, split = 'below' })
+      )
+      matches(
+        'E36: Not enough room$',
+        pcall_err(api.nvim_win_set_config, t2_float, { win = t2_top_split, split = 'above' })
+      )
+      matches(
+        'E36: Not enough room$',
+        pcall_err(api.nvim_win_set_config, t2_float, { win = t2_top_split, split = 'below' })
+      )
+      matches(
+        'E36: Not enough room$',
+        pcall_err(api.nvim_win_set_config, t2_float, { win = t2_bot_split, split = 'above' })
+      )
+      matches(
+        'E36: Not enough room$',
+        pcall_err(api.nvim_win_set_config, t2_float, { win = t2_bot_split, split = 'below' })
+      )
+      eq(t2_cur_win, api.nvim_get_current_win())
+      eq(t2_info, tp_info(t2))
+      eq(t2_float_config, api.nvim_win_get_config(t2_float))
+
+      -- Try to move windows from the 1st tabpage to the 2nd.
+      command('tabfirst | split | wincmd _')
+      local t1 = api.nvim_get_current_tabpage()
+      local t1_cur_win = api.nvim_get_current_win()
+      local t1_float = api.nvim_open_win(
+        0,
+        false,
+        { relative = 'editor', row = 5, col = 3, width = 7, height = 6 }
+      )
+      local t1_float_config = api.nvim_win_get_config(t1_float)
+      local t1_info = tp_info(t1)
+      matches(
+        'E36: Not enough room$',
+        pcall_err(api.nvim_win_set_config, 0, { win = t2_top_split, split = 'above' })
+      )
+      matches(
+        'E36: Not enough room$',
+        pcall_err(api.nvim_win_set_config, 0, { win = t2_top_split, split = 'below' })
+      )
+      matches(
+        'E36: Not enough room$',
+        pcall_err(api.nvim_win_set_config, 0, { win = t2_bot_split, split = 'above' })
+      )
+      matches(
+        'E36: Not enough room$',
+        pcall_err(api.nvim_win_set_config, 0, { win = t2_bot_split, split = 'below' })
+      )
+      matches(
+        'E36: Not enough room$',
+        pcall_err(api.nvim_win_set_config, t1_float, { win = t2_top_split, split = 'above' })
+      )
+      matches(
+        'E36: Not enough room$',
+        pcall_err(api.nvim_win_set_config, t1_float, { win = t2_top_split, split = 'below' })
+      )
+      matches(
+        'E36: Not enough room$',
+        pcall_err(api.nvim_win_set_config, t1_float, { win = t2_bot_split, split = 'above' })
+      )
+      matches(
+        'E36: Not enough room$',
+        pcall_err(api.nvim_win_set_config, t1_float, { win = t2_bot_split, split = 'below' })
+      )
+      eq(t1_cur_win, api.nvim_get_current_win())
+      eq(t1_info, tp_info(t1))
+      eq(t1_float_config, api.nvim_win_get_config(t1_float))
+    end)
+
+    it('attempt to move window from other tabpage with no room', function()
+      -- Fill up the 1st tabpage with horizontal splits, then create a 2nd with only a few. Go back
+      -- to the 1st and try to move windows from the 2nd (while it's non-current) to it. Check that
+      -- window positions and sizes in the 2nd are unchanged.
+      command('set laststatus=0')
+      matches('E36: Not enough room$', pcall_err(command, 'execute "split|"->repeat(&lines)'))
+
+      command('tab split')
+      local t2 = api.nvim_get_current_tabpage()
+      local t2_top = api.nvim_get_current_win()
+      command('belowright split')
+      local t2_mid_left = api.nvim_get_current_win()
+      command('belowright vsplit')
+      local t2_mid_right = api.nvim_get_current_win()
+      command('split | wincmd J')
+      local t2_bot = api.nvim_get_current_win()
+      local tp_info = define_tp_info_function()
+      local t2_info = tp_info(t2)
+      eq({
+        'col',
+        {
+          { 'leaf', t2_top },
+          {
+            'row',
+            {
+              { 'leaf', t2_mid_left },
+              { 'leaf', t2_mid_right },
+            },
+          },
+          { 'leaf', t2_bot },
+        },
+      }, t2_info.layout)
+
+      local function try_move_t2_wins_to_t1()
+        for _, w in ipairs({ t2_bot, t2_mid_left, t2_mid_right, t2_top }) do
+          matches(
+            'E36: Not enough room$',
+            pcall_err(api.nvim_win_set_config, w, { win = 0, split = 'below' })
+          )
+          eq(t2_info, tp_info(t2))
+        end
+      end
+      command('tabfirst')
+      try_move_t2_wins_to_t1()
+      -- Go to the 2nd tabpage to ensure nothing changes after win_comp_pos, last_status, .etc.
+      -- from enter_tabpage.
+      command('tabnext')
+      eq(t2_info, tp_info(t2))
+
+      -- Check things are fine with the global statusline too, for good measure.
+      -- Set it while the 2nd tabpage is current, so last_status runs for it.
+      command('set laststatus=3')
+      t2_info = tp_info(t2)
+      command('tabfirst')
+      try_move_t2_wins_to_t1()
+    end)
+
+    it('handles cmdwin and textlock restrictions', function()
+      command('tabnew')
+      local t2 = api.nvim_get_current_tabpage()
+      local t2_win = api.nvim_get_current_win()
+      command('tabfirst')
+      local t1_move_win = api.nvim_get_current_win()
+      command('split')
+
+      -- Can't move the cmdwin, or its old curwin to a different tabpage.
+      local old_curwin = api.nvim_get_current_win()
+      feed('q:')
+      eq(
+        'E11: Invalid in command-line window; <CR> executes, CTRL-C quits',
+        pcall_err(api.nvim_win_set_config, 0, { split = 'left', win = t2_win })
+      )
+      eq(
+        'E11: Invalid in command-line window; <CR> executes, CTRL-C quits',
+        pcall_err(api.nvim_win_set_config, old_curwin, { split = 'left', win = t2_win })
+      )
+      -- But we can move other windows.
+      api.nvim_win_set_config(t1_move_win, { split = 'left', win = t2_win })
+      eq(t2, api.nvim_win_get_tabpage(t1_move_win))
+      command('quit!')
+
+      -- Can't configure windows such that the cmdwin would become the only non-float.
+      command('only!')
+      feed('q:')
+      eq(
+        'E11: Invalid in command-line window; <CR> executes, CTRL-C quits',
+        pcall_err(
+          api.nvim_win_set_config,
+          old_curwin,
+          { relative = 'editor', row = 0, col = 0, width = 5, height = 5 }
+        )
+      )
+      -- old_curwin is now no longer the only other non-float, so we can make it floating now.
+      local t1_new_win = api.nvim_open_win(
+        api.nvim_create_buf(true, true),
+        false,
+        { split = 'left', win = old_curwin }
+      )
+      api.nvim_win_set_config(
+        old_curwin,
+        { relative = 'editor', row = 0, col = 0, width = 5, height = 5 }
+      )
+      eq('editor', api.nvim_win_get_config(old_curwin).relative)
+      -- ...which means we shouldn't be able to also make the new window floating too!
+      eq(
+        'E11: Invalid in command-line window; <CR> executes, CTRL-C quits',
+        pcall_err(
+          api.nvim_win_set_config,
+          t1_new_win,
+          { relative = 'editor', row = 0, col = 0, width = 5, height = 5 }
+        )
+      )
+      -- Nothing ought to stop us from making the cmdwin itself floating, though...
+      api.nvim_win_set_config(0, { relative = 'editor', row = 0, col = 0, width = 5, height = 5 })
+      eq('editor', api.nvim_win_get_config(0).relative)
+      -- We can't make our new window from before floating too, as it's now the only non-float.
+      eq(
+        'Cannot change last window into float',
+        pcall_err(
+          api.nvim_win_set_config,
+          t1_new_win,
+          { relative = 'editor', row = 0, col = 0, width = 5, height = 5 }
+        )
+      )
+      command('quit!')
+
+      -- Can't switch away from window before moving it to a different tabpage during textlock.
+      exec(([[
+        new
+        call setline(1, 'foo')
+        setlocal debug=throw indentexpr=nvim_win_set_config(0,#{split:'left',win:%d})
+      ]]):format(t2_win))
+      local cur_win = api.nvim_get_current_win()
+      matches(
+        'E565: Not allowed to change text or change window$',
+        pcall_err(command, 'normal! ==')
+      )
+      eq(cur_win, api.nvim_get_current_win())
+    end)
+
+    it('updates statusline when moving bottom split', function()
+      local screen = Screen.new(10, 10)
+      screen:set_default_attr_ids({
+        [0] = { bold = true, foreground = Screen.colors.Blue }, -- NonText
+        [1] = { bold = true, reverse = true }, -- StatusLine
+      })
+      screen:attach()
+      exec([[
+        set laststatus=0
+        belowright split
+        call nvim_win_set_config(0, #{split: 'above', win: win_getid(winnr('#'))})
+      ]])
+      screen:expect([[
+        ^            |
+        {0:~           }|*3
+        {1:[No Name]   }|
+                    |
+        {0:~           }|*3
+                    |
+      ]])
+    end)
+
+    it("updates tp_curwin of moved window's original tabpage", function()
+      local t1 = api.nvim_get_current_tabpage()
+      command('tab split | split')
+      local t2 = api.nvim_get_current_tabpage()
+      local t2_alt_win = api.nvim_get_current_win()
+      command('vsplit')
+      local t2_cur_win = api.nvim_get_current_win()
+      command('tabprevious')
+      eq(t2_cur_win, api.nvim_tabpage_get_win(t2))
+
+      -- tp_curwin is unchanged when moved within the same tabpage.
+      api.nvim_win_set_config(t2_cur_win, { split = 'left', win = t2_alt_win })
+      eq(t2_cur_win, api.nvim_tabpage_get_win(t2))
+
+      -- Also unchanged if the move failed.
+      command('let &winwidth = &columns | let &winminwidth = &columns')
+      matches(
+        'E36: Not enough room$',
+        pcall_err(api.nvim_win_set_config, t2_cur_win, { split = 'left', win = 0 })
+      )
+      eq(t2_cur_win, api.nvim_tabpage_get_win(t2))
+      command('set winminwidth& winwidth&')
+
+      -- But is changed if successfully moved to a different tabpage.
+      api.nvim_win_set_config(t2_cur_win, { split = 'left', win = 0 })
+      eq(t2_alt_win, api.nvim_tabpage_get_win(t2))
+      eq(t1, api.nvim_win_get_tabpage(t2_cur_win))
+
+      -- Now do it for a float, which has different altwin logic.
+      command('tabnext')
+      t2_cur_win =
+        api.nvim_open_win(0, true, { relative = 'editor', row = 5, col = 5, width = 5, height = 5 })
+      eq(t2_alt_win, fn.win_getid(fn.winnr('#')))
+      command('tabprevious')
+      eq(t2_cur_win, api.nvim_tabpage_get_win(t2))
+
+      api.nvim_win_set_config(t2_cur_win, { split = 'left', win = 0 })
+      eq(t2_alt_win, api.nvim_tabpage_get_win(t2))
+      eq(t1, api.nvim_win_get_tabpage(t2_cur_win))
+    end)
   end)
 
   describe('get_config', function()