neovim/test/functional/api/vim_spec.lua

local helpers = require('test.functional.helpers')(after_each)
local Screen = require('test.functional.ui.screen')
local luv = require('luv')

local fmt = string.format
local assert_alive = helpers.assert_alive
local NIL = helpers.NIL
local clear, nvim, eq, neq = helpers.clear, helpers.nvim, helpers.eq, helpers.neq
local command = helpers.command
local exec = helpers.exec
local exec_capture = helpers.exec_capture
local eval = helpers.eval
local expect = helpers.expect
local funcs = helpers.funcs
local meths = helpers.meths
local matches = helpers.matches
local pesc = helpers.pesc
local mkdir_p = helpers.mkdir_p
local ok, nvim_async, feed = helpers.ok, helpers.nvim_async, helpers.feed
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 expect_exit = helpers.expect_exit
local skip = helpers.skip

local pcall_err = helpers.pcall_err
local format_string = helpers.format_string
local intchar2lua = helpers.intchar2lua
local mergedicts_copy = helpers.mergedicts_copy
local endswith = helpers.endswith

describe('API', function()
  before_each(clear)

  it('validates requests', function()
    -- RPC
    matches('Invalid method: bogus$',
      pcall_err(request, 'bogus'))
    matches('Invalid method: … の り 。…$',
      pcall_err(request, '… の り 。…'))
    matches('Invalid method: <empty>$',
      pcall_err(request, ''))

    -- Non-RPC: rpcrequest(v:servername) uses internal channel.
    matches('Invalid method: … の り 。…$',
      pcall_err(request, 'nvim_eval',
        [=[rpcrequest(sockconnect('pipe', v:servername, {'rpc':1}), '… の り 。…')]=]))
    matches('Invalid method: bogus$',
      pcall_err(request, 'nvim_eval',
        [=[rpcrequest(sockconnect('pipe', v:servername, {'rpc':1}), 'bogus')]=]))

    -- XXX: This must be the last one, else next one will fail:
    --      "Packer instance already working. Use another Packer ..."
    matches("can't serialize object of type .$",
      pcall_err(request, nil))
  end)

  it('handles errors in async requests', function()
    local error_types = meths.get_api_info()[2].error_types
    nvim_async('bogus')
    eq({'notification', 'nvim_error_event',
        {error_types.Exception.id, 'Invalid method: nvim_bogus'}}, next_msg())
    -- error didn't close channel.
    assert_alive()
  end)

  it('failed async request emits nvim_error_event', function()
    local error_types = meths.get_api_info()[2].error_types
    nvim_async('command', 'bogus')
    eq({'notification', 'nvim_error_event',
        {error_types.Exception.id, 'Vim:E492: Not an editor command: bogus'}},
        next_msg())
    -- error didn't close channel.
    assert_alive()
  end)

  it('does not set CA_COMMAND_BUSY #7254', function()
    nvim('command', 'split')
    nvim('command', 'autocmd WinEnter * startinsert')
    nvim('command', 'wincmd w')
    eq({mode='i', blocking=false}, nvim("get_mode"))
  end)

  describe('nvim_exec2', function()
    it('always returns table', function()
      -- In built version this results into `vim.empty_dict()`
      eq({}, nvim('exec2', 'echo "Hello"', {}))
      eq({}, nvim('exec2', 'echo "Hello"', { output = false }))
      eq({ output = 'Hello' }, nvim('exec2', 'echo "Hello"', { output = true }))
    end)

    it('default options', function()
      -- Should be equivalent to { output = false }
      nvim('exec2', "let x0 = 'a'", {})
      eq('a', nvim('get_var', 'x0'))
    end)

    it('one-line input', function()
      nvim('exec2', "let x1 = 'a'", { output = false })
      eq('a', nvim('get_var', 'x1'))
    end)

    it(':verbose set {option}?', function()
      nvim('exec2', 'set nowrap', { output = false })
      eq({ output = 'nowrap\n\tLast set from anonymous :source' },
        nvim('exec2', 'verbose set wrap?', { output = true }))

      -- Using script var to force creation of a script item
      nvim('exec2', [[
        let s:a = 1
        set nowrap
      ]], { output = false })
      eq({ output = 'nowrap\n\tLast set from anonymous :source (script id 1)' },
        nvim('exec2', 'verbose set wrap?', { output = true }))
    end)

    it('multiline input', function()
      -- Heredoc + empty lines.
      nvim('exec2', "let x2 = 'a'\n", { output = false })
      eq('a', nvim('get_var', 'x2'))
      nvim('exec2','lua <<EOF\n\n\n\ny=3\n\n\nEOF', { output = false })
      eq(3, nvim('eval', "luaeval('y')"))

      eq({}, nvim('exec2', 'lua <<EOF\ny=3\nEOF', { output = false }))
      eq(3, nvim('eval', "luaeval('y')"))

      -- Multiple statements
      nvim('exec2', 'let x1=1\nlet x2=2\nlet x3=3\n', { output = false })
      eq(1, nvim('eval', 'x1'))
      eq(2, nvim('eval', 'x2'))
      eq(3, nvim('eval', 'x3'))

      -- Functions
      nvim('exec2', 'function Foo()\ncall setline(1,["xxx"])\nendfunction', { output = false })
      eq('', nvim('get_current_line'))
      nvim('exec2', 'call Foo()', { output = false })
      eq('xxx', nvim('get_current_line'))

      -- Autocmds
      nvim('exec2','autocmd BufAdd * :let x1 = "Hello"', { output = false })
      nvim('command', 'new foo')
      eq('Hello', request('nvim_eval', 'g:x1'))

      -- Line continuations
      nvim('exec2', [[
        let abc = #{
          \ a: 1,
         "\ b: 2,
          \ c: 3
          \ }]], { output = false })
      eq({a = 1, c = 3}, request('nvim_eval', 'g:abc'))

      -- try no spaces before continuations to catch off-by-one error
      nvim('exec2', 'let ab = #{\n\\a: 98,\n"\\ b: 2\n\\}', { output = false })
      eq({a = 98}, request('nvim_eval', 'g:ab'))

      -- Script scope (s:)
      eq({ output = 'ahoy! script-scoped varrrrr' }, nvim('exec2', [[
          let s:pirate = 'script-scoped varrrrr'
          function! s:avast_ye_hades(s) abort
            return a:s .. ' ' .. s:pirate
          endfunction
          echo <sid>avast_ye_hades('ahoy!')
        ]], { output = true }))

      eq({ output = "{'output': 'ahoy! script-scoped varrrrr'}" }, nvim('exec2', [[
          let s:pirate = 'script-scoped varrrrr'
          function! Avast_ye_hades(s) abort
            return a:s .. ' ' .. s:pirate
          endfunction
          echo nvim_exec2('echo Avast_ye_hades(''ahoy!'')', {'output': v:true})
        ]], { output = true }))

      matches('Vim%(echo%):E121: Undefined variable: s:pirate$',
        pcall_err(request, 'nvim_exec2', [[
          let s:pirate = 'script-scoped varrrrr'
          call nvim_exec2('echo s:pirate', {'output': v:true})
        ]], { output = false }))

      -- Script items are created only on script var access
      eq({ output = '1\n0' }, nvim('exec2', [[
          echo expand("<SID>")->empty()
          let s:a = 123
          echo expand("<SID>")->empty()
        ]], { output = true }))

      eq({ output = '1\n0' }, nvim('exec2', [[
          echo expand("<SID>")->empty()
          function s:a() abort
          endfunction
          echo expand("<SID>")->empty()
        ]], { output = true }))
    end)

    it('non-ASCII input', function()
      nvim('exec2', [=[
        new
        exe "normal! i ax \n Ax "
        :%s/ax/--a1234--/g | :%s/Ax/--A1234--/g
      ]=], { output = false })
      nvim('command', '1')
      eq(' --a1234-- ', nvim('get_current_line'))
      nvim('command', '2')
      eq(' --A1234-- ', nvim('get_current_line'))

      nvim('exec2', [[
        new
        call setline(1,['xxx'])
        call feedkeys('r')
        call feedkeys('ñ', 'xt')
      ]], { output = false })
      eq('ñxx', nvim('get_current_line'))
    end)

    it('execution error', function()
      eq('nvim_exec2(): Vim:E492: Not an editor command: bogus_command',
        pcall_err(request, 'nvim_exec2', 'bogus_command', {}))
      eq('', nvim('eval', 'v:errmsg'))  -- v:errmsg was not updated.
      eq('', eval('v:exception'))

      eq('nvim_exec2(): Vim(buffer):E86: Buffer 23487 does not exist',
        pcall_err(request, 'nvim_exec2', 'buffer 23487', {}))
      eq('', eval('v:errmsg'))  -- v:errmsg was not updated.
      eq('', eval('v:exception'))
    end)

    it('recursion', function()
      local fname = tmpname()
      write_file(fname, 'let x1 = "set from :source file"\n')
      -- nvim_exec2
      --   :source
      --     nvim_exec2
      request('nvim_exec2', [[
        let x2 = substitute('foo','o','X','g')
        let x4 = 'should be overwritten'
        call nvim_exec2("source ]]..fname..[[\nlet x3 = substitute('foo','foo','set by recursive nvim_exec2','g')\nlet x5='overwritten'\nlet x4=x5\n", {'output': v:false})
      ]], { output = false })
      eq('set from :source file', request('nvim_get_var', 'x1'))
      eq('fXX', request('nvim_get_var', 'x2'))
      eq('set by recursive nvim_exec2', request('nvim_get_var', 'x3'))
      eq('overwritten', request('nvim_get_var', 'x4'))
      eq('overwritten', request('nvim_get_var', 'x5'))
      os.remove(fname)
    end)

    it('traceback', function()
      local fname = tmpname()
      write_file(fname, 'echo "hello"\n')
      local sourcing_fname = tmpname()
      write_file(sourcing_fname, 'call nvim_exec2("source '..fname..'", {"output": v:false})\n')
      meths.exec2('set verbose=2', { output = false })
      local traceback_output = 'line 0: sourcing "'..sourcing_fname..'"\n'..
        'line 0: sourcing "'..fname..'"\n'..
        'hello\n'..
        'finished sourcing '..fname..'\n'..
        'continuing in nvim_exec2() called at '..sourcing_fname..':1\n'..
        'finished sourcing '..sourcing_fname..'\n'..
        'continuing in nvim_exec2() called at nvim_exec2():0'
      eq({ output = traceback_output },
        meths.exec2('call nvim_exec2("source '..sourcing_fname..'", {"output": v:false})', { output = true }))
      os.remove(fname)
      os.remove(sourcing_fname)
    end)

    it('returns output', function()
      eq({ output = 'this is spinal tap' },
         nvim('exec2', 'lua <<EOF\n\n\nprint("this is spinal tap")\n\n\nEOF', { output = true }))
      eq({ output = '' }, nvim('exec2', 'echo', { output = true }))
      eq({ output = 'foo 42' }, nvim('exec2', 'echo "foo" 42', { output = true }))
    end)

    it('displays messages when opts.output=false', function()
      local screen = Screen.new(40, 8)
      screen:attach()
      screen:set_default_attr_ids({
        [0] = {bold=true, foreground=Screen.colors.Blue},
      })
      meths.exec2("echo 'hello'", { output = false })
      screen:expect{grid=[[
        ^                                        |
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        hello                                   |
      ]]}
    end)

    it('doesn\'t display messages when output=true', function()
      local screen = Screen.new(40, 6)
      screen:attach()
      screen:set_default_attr_ids({
        [0] = {bold=true, foreground=Screen.colors.Blue},
      })
      meths.exec2("echo 'hello'", { output = true })
      screen:expect{grid=[[
        ^                                        |
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
                                                |
      ]]}
      exec([[
        func Print()
          call nvim_exec2('echo "hello"', { 'output': v:true })
        endfunc
      ]])
      feed([[:echon 1 | call Print() | echon 5<CR>]])
      screen:expect{grid=[[
        ^                                        |
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        15                                      |
      ]]}
    end)
  end)

  describe('nvim_command', function()
    it('works', function()
      local fname = tmpname()
      nvim('command', 'new')
      nvim('command', 'edit '..fname)
      nvim('command', 'normal itesting\napi')
      nvim('command', 'w')
      local f = assert(io.open(fname))
      if is_os('win') then
        eq('testing\r\napi\r\n', f:read('*a'))
      else
        eq('testing\napi\n', f:read('*a'))
      end
      f:close()
      os.remove(fname)
    end)

    it('Vimscript validation error: fails with specific error', function()
      local status, rv = pcall(nvim, "command", "bogus_command")
      eq(false, status)                       -- nvim_command() failed.
      eq("E492:", string.match(rv, "E%d*:"))  -- Vimscript error was returned.
      eq('', nvim('eval', 'v:errmsg'))        -- v:errmsg was not updated.
      eq('', eval('v:exception'))
    end)

    it('Vimscript execution error: fails with specific error', function()
      local status, rv = pcall(nvim, "command", "buffer 23487")
      eq(false, status)                 -- nvim_command() failed.
      eq("E86: Buffer 23487 does not exist", string.match(rv, "E%d*:.*"))
      eq('', eval('v:errmsg'))  -- v:errmsg was not updated.
      eq('', eval('v:exception'))
    end)

    it('gives E493 instead of prompting on backwards range', function()
      command('split')
      eq('Vim(windo):E493: Backwards range given: 2,1windo echo',
         pcall_err(command, '2,1windo echo'))
    end)
  end)

  describe('nvim_command_output', function()
    it('does not induce hit-enter prompt', function()
      nvim("ui_attach", 80, 20, {})
      -- Induce a hit-enter prompt use nvim_input (non-blocking).
      nvim('command', 'set cmdheight=1')
      nvim('input', [[:echo "hi\nhi2"<CR>]])

      -- Verify hit-enter prompt.
      eq({mode='r', blocking=true}, nvim("get_mode"))
      nvim('input', [[<C-c>]])

      -- Verify NO hit-enter prompt.
      nvim('command_output', [[echo "hi\nhi2"]])
      eq({mode='n', blocking=false}, nvim("get_mode"))
    end)

    it('captures command output', function()
      eq('this is\nspinal tap',
         nvim('command_output', [[echo "this is\nspinal tap"]]))
      eq('no line ending!',
         nvim('command_output', [[echon "no line ending!"]]))
    end)

    it('captures empty command output', function()
      eq('', nvim('command_output', 'echo'))
    end)

    it('captures single-char command output', function()
      eq('x', nvim('command_output', 'echo "x"'))
    end)

    it('captures multiple commands', function()
      eq('foo\n  1 %a   "[No Name]"                    line 1',
        nvim('command_output', 'echo "foo" | ls'))
    end)

    it('captures nested execute()', function()
      eq('\nnested1\nnested2\n  1 %a   "[No Name]"                    line 1',
        nvim('command_output',
          [[echo execute('echo "nested1\nnested2"') | ls]]))
    end)

    it('captures nested nvim_command_output()', function()
      eq('nested1\nnested2\n  1 %a   "[No Name]"                    line 1',
        nvim('command_output',
          [[echo nvim_command_output('echo "nested1\nnested2"') | ls]]))
    end)

    it('returns shell |:!| output', function()
      local win_lf = is_os('win') and '\r' or ''
      eq(':!echo foo\r\n\nfoo'..win_lf..'\n', nvim('command_output', [[!echo foo]]))
    end)

    it('Vimscript validation error: fails with specific error', function()
      local status, rv = pcall(nvim, "command_output", "bogus commannnd")
      eq(false, status)                 -- nvim_command_output() failed.
      eq("E492: Not an editor command: bogus commannnd",
         string.match(rv, "E%d*:.*"))
      eq('', eval('v:errmsg'))  -- v:errmsg was not updated.
      -- Verify NO hit-enter prompt.
      eq({mode='n', blocking=false}, nvim("get_mode"))
    end)

    it('Vimscript execution error: fails with specific error', function()
      local status, rv = pcall(nvim, "command_output", "buffer 42")
      eq(false, status)                 -- nvim_command_output() failed.
      eq("E86: Buffer 42 does not exist", string.match(rv, "E%d*:.*"))
      eq('', eval('v:errmsg'))  -- v:errmsg was not updated.
      -- Verify NO hit-enter prompt.
      eq({mode='n', blocking=false}, nvim("get_mode"))
    end)

    it('Does not cause heap buffer overflow with large output', function()
      eq(eval('string(range(1000000))'),
         nvim('command_output', 'echo range(1000000)'))
    end)
  end)

  describe('nvim_eval', function()
    it('works', function()
      nvim('command', 'let g:v1 = "a"')
      nvim('command', 'let g:v2 = [1, 2, {"v3": 3}]')
      eq({v1 = 'a', v2 = { 1, 2, { v3 = 3 } } }, nvim('eval', 'g:'))
    end)

    it('handles NULL-initialized strings correctly', function()
      eq(1, nvim('eval',"matcharg(1) == ['', '']"))
      eq({'', ''}, nvim('eval','matcharg(1)'))
    end)

    it('works under deprecated name', function()
      eq(2, request("vim_eval", "1+1"))
    end)

    it("Vimscript error: returns error details, does NOT update v:errmsg", function()
      eq('Vim:E121: Undefined variable: bogus',
        pcall_err(request, 'nvim_eval', 'bogus expression'))
      eq('', eval('v:errmsg'))  -- v:errmsg was not updated.
    end)
  end)

  describe('nvim_call_function', function()
    it('works', function()
      nvim('call_function', 'setqflist', { { { filename = 'something', lnum = 17 } }, 'r' })
      eq(17, nvim('call_function', 'getqflist', {})[1].lnum)
      eq(17, nvim('call_function', 'eval', {17}))
      eq('foo', nvim('call_function', 'simplify', {'this/./is//redundant/../../../foo'}))
    end)

    it("Vimscript validation error: returns specific error, does NOT update v:errmsg", function()
      eq('Vim:E117: Unknown function: bogus function',
        pcall_err(request, 'nvim_call_function', 'bogus function', {'arg1'}))
      eq('Vim:E119: Not enough arguments for function: atan',
        pcall_err(request, 'nvim_call_function', 'atan', {}))
      eq('', eval('v:exception'))
      eq('', eval('v:errmsg'))  -- v:errmsg was not updated.
    end)

    it("Vimscript error: returns error details, does NOT update v:errmsg", function()
      eq('Vim:E808: Number or Float required',
        pcall_err(request, 'nvim_call_function', 'atan', {'foo'}))
      eq('Vim:Invalid channel stream "xxx"',
        pcall_err(request, 'nvim_call_function', 'chanclose', {999, 'xxx'}))
      eq('Vim:E900: Invalid channel id',
        pcall_err(request, 'nvim_call_function', 'chansend', {999, 'foo'}))
      eq('', eval('v:exception'))
      eq('', eval('v:errmsg'))  -- v:errmsg was not updated.
    end)

    it("Vimscript exception: returns exception details, does NOT update v:errmsg", function()
      source([[
        function! Foo() abort
          throw 'wtf'
        endfunction
      ]])
      eq('function Foo, line 1: wtf', pcall_err(request, 'nvim_call_function', 'Foo', {}))
      eq('', eval('v:exception'))
      eq('', eval('v:errmsg'))  -- v:errmsg was not updated.
    end)

    it('validation', function()
      local too_many_args = { 'x', 'x', 'x', 'x', 'x', 'x', 'x', 'x', 'x', 'x', 'x', 'x', 'x', 'x', 'x', 'x', 'x', 'x', 'x', 'x', 'x' }
      source([[
        function! Foo(...) abort
          echo a:000
        endfunction
      ]])
      -- E740
      eq('Function called with too many arguments',
        pcall_err(request, 'nvim_call_function', 'Foo', too_many_args))
    end)
  end)

  describe('nvim_call_dict_function', function()
    it('invokes Vimscript dict function', function()
      source([[
        function! F(name) dict
          return self.greeting.', '.a:name.'!'
        endfunction
        let g:test_dict_fn = { 'greeting':'Hello', 'F':function('F') }

        let g:test_dict_fn2 = { 'greeting':'Hi' }
        function g:test_dict_fn2.F2(name)
          return self.greeting.', '.a:name.' ...'
        endfunction
      ]])

      -- :help Dictionary-function
      eq('Hello, World!', nvim('call_dict_function', 'g:test_dict_fn', 'F', {'World'}))
      -- Funcref is sent as NIL over RPC.
      eq({ greeting = 'Hello', F = NIL }, nvim('get_var', 'test_dict_fn'))

      -- :help numbered-function
      eq('Hi, Moon ...', nvim('call_dict_function', 'g:test_dict_fn2', 'F2', {'Moon'}))
      -- Funcref is sent as NIL over RPC.
      eq({ greeting = 'Hi', F2 = NIL }, nvim('get_var', 'test_dict_fn2'))

      -- Function specified via RPC dict.
      source('function! G() dict\n  return "@".(self.result)."@"\nendfunction')
      eq('@it works@', nvim('call_dict_function', { result = 'it works', G = 'G'}, 'G', {}))
    end)

    it('validation', function()
      command('let g:d={"baz":"zub","meep":[]}')
      eq('Not found: bogus',
        pcall_err(request, 'nvim_call_dict_function', 'g:d', 'bogus', {1,2}))
      eq('Not a function: baz',
        pcall_err(request, 'nvim_call_dict_function', 'g:d', 'baz', {1,2}))
      eq('Not a function: meep',
        pcall_err(request, 'nvim_call_dict_function', 'g:d', 'meep', {1,2}))
      eq('Vim:E117: Unknown function: f',
        pcall_err(request, 'nvim_call_dict_function', { f = '' }, 'f', {1,2}))
      eq('Not a function: f',
        pcall_err(request, 'nvim_call_dict_function', "{ 'f': '' }", 'f', {1,2}))
      eq('dict argument type must be String or Dictionary',
        pcall_err(request, 'nvim_call_dict_function', 42, 'f', {1,2}))
      eq('Failed to evaluate dict expression',
        pcall_err(request, 'nvim_call_dict_function', 'foo', 'f', {1,2}))
      eq('dict not found',
        pcall_err(request, 'nvim_call_dict_function', '42', 'f', {1,2}))
      eq('Invalid (empty) function name',
        pcall_err(request, 'nvim_call_dict_function', "{ 'f': '' }", '', {1,2}))
    end)
  end)

  describe('nvim_set_current_dir', function()
    local start_dir

    before_each(function()
      funcs.mkdir("Xtestdir")
      start_dir = funcs.getcwd()
    end)

    after_each(function()
      helpers.rmdir("Xtestdir")
    end)

    it('works', function()
      meths.set_current_dir("Xtestdir")
      eq(funcs.getcwd(), start_dir .. helpers.get_pathsep() .. "Xtestdir")
    end)

    it('sets previous directory', function()
      meths.set_current_dir("Xtestdir")
      command('cd -')
      eq(funcs.getcwd(), start_dir)
    end)
  end)

  describe('nvim_exec_lua', function()
    it('works', function()
      meths.exec_lua('vim.api.nvim_set_var("test", 3)', {})
      eq(3, meths.get_var('test'))

      eq(17, meths.exec_lua('a, b = ...\nreturn a + b', {10,7}))

      eq(NIL, meths.exec_lua('function xx(a,b)\nreturn a..b\nend',{}))
      eq("xy", meths.exec_lua('return xx(...)', {'x','y'}))

      -- Deprecated name: nvim_execute_lua.
      eq("xy", meths.execute_lua('return xx(...)', {'x','y'}))
    end)

    it('reports errors', function()
      eq([[Error loading lua: [string "<nvim>"]:0: '=' expected near '+']],
        pcall_err(meths.exec_lua, 'a+*b', {}))

      eq([[Error loading lua: [string "<nvim>"]:0: unexpected symbol near '1']],
        pcall_err(meths.exec_lua, '1+2', {}))

      eq([[Error loading lua: [string "<nvim>"]:0: unexpected symbol]],
        pcall_err(meths.exec_lua, 'aa=bb\0', {}))

      eq([[attempt to call global 'bork' (a nil value)]],
        pcall_err(meths.exec_lua, 'bork()', {}))

      eq('did\nthe\nfail',
        pcall_err(meths.exec_lua, 'error("did\\nthe\\nfail")', {}))
    end)

    it('uses native float values', function()
      eq(2.5, meths.exec_lua("return select(1, ...)", {2.5}))
      eq("2.5", meths.exec_lua("return vim.inspect(...)", {2.5}))

      -- "special" float values are still accepted as return values.
      eq(2.5, meths.exec_lua("return vim.api.nvim_eval('2.5')", {}))
      eq("{\n  [false] = 2.5,\n  [true] = 3\n}", meths.exec_lua("return vim.inspect(vim.api.nvim_eval('2.5'))", {}))
    end)
  end)

  describe('nvim_notify', function()
    it('can notify a info message', function()
      nvim("notify", "hello world", 2, {})
    end)

    it('can be overridden', function()
      command("lua vim.notify = function(...) return 42 end")
      eq(42, meths.exec_lua("return vim.notify('Hello world')", {}))
      nvim("notify", "hello world", 4, {})
    end)
  end)

  describe('nvim_input', function()
    it("Vimscript error: does NOT fail, updates v:errmsg", function()
      local status, _ = pcall(nvim, "input", ":call bogus_fn()<CR>")
      local v_errnum = string.match(nvim("eval", "v:errmsg"), "E%d*:")
      eq(true, status)        -- nvim_input() did not fail.
      eq("E117:", v_errnum)   -- v:errmsg was updated.
    end)

    it('does not crash even if trans_special result is largest #11788, #12287', function()
      command("call nvim_input('<M-'.nr2char(0x40000000).'>')")
      eq(1, eval('1'))
    end)
  end)

  describe('nvim_paste', function()
    it('validation', function()
      eq("Invalid 'phase': -2",
        pcall_err(request, 'nvim_paste', 'foo', true, -2))
      eq("Invalid 'phase': 4",
        pcall_err(request, 'nvim_paste', 'foo', true, 4))
    end)
    local function run_streamed_paste_tests()
      it('stream: multiple chunks form one undo-block', function()
        nvim('paste', '1/chunk 1 (start)\n', true, 1)
        nvim('paste', '1/chunk 2 (end)\n', true, 3)
        local expected1 = [[
          1/chunk 1 (start)
          1/chunk 2 (end)
          ]]
        expect(expected1)
        nvim('paste', '2/chunk 1 (start)\n', true, 1)
        nvim('paste', '2/chunk 2\n', true, 2)
        expect([[
          1/chunk 1 (start)
          1/chunk 2 (end)
          2/chunk 1 (start)
          2/chunk 2
          ]])
        nvim('paste', '2/chunk 3\n', true, 2)
        nvim('paste', '2/chunk 4 (end)\n', true, 3)
        expect([[
          1/chunk 1 (start)
          1/chunk 2 (end)
          2/chunk 1 (start)
          2/chunk 2
          2/chunk 3
          2/chunk 4 (end)
          ]])
        feed('u')  -- Undo.
        expect(expected1)
      end)
      it('stream: Insert mode', function()
        -- If nvim_paste() calls :undojoin without making any changes, this makes it an error.
        feed('afoo<Esc>u')
        feed('i')
        nvim('paste', 'aaaaaa', false, 1)
        nvim('paste', 'bbbbbb', false, 2)
        nvim('paste', 'cccccc', false, 2)
        nvim('paste', 'dddddd', false, 3)
        expect('aaaaaabbbbbbccccccdddddd')
        feed('<Esc>u')
        expect('')
      end)
      describe('stream: Normal mode', function()
        describe('on empty line', function()
          before_each(function()
            -- If nvim_paste() calls :undojoin without making any changes, this makes it an error.
            feed('afoo<Esc>u')
          end)
          after_each(function()
            feed('u')
            expect('')
          end)
          it('pasting one line', function()
            nvim('paste', 'aaaaaa', false, 1)
            nvim('paste', 'bbbbbb', false, 2)
            nvim('paste', 'cccccc', false, 2)
            nvim('paste', 'dddddd', false, 3)
            expect('aaaaaabbbbbbccccccdddddd')
          end)
          it('pasting multiple lines', function()
            nvim('paste', 'aaaaaa\n', false, 1)
            nvim('paste', 'bbbbbb\n', false, 2)
            nvim('paste', 'cccccc\n', false, 2)
            nvim('paste', 'dddddd', false, 3)
            expect([[
            aaaaaa
            bbbbbb
            cccccc
            dddddd]])
          end)
        end)
        describe('not at the end of a line', function()
          before_each(function()
            feed('i||<Esc>')
            -- If nvim_paste() calls :undojoin without making any changes, this makes it an error.
            feed('afoo<Esc>u')
            feed('0')
          end)
          after_each(function()
            feed('u')
            expect('||')
          end)
          it('pasting one line', function()
            nvim('paste', 'aaaaaa', false, 1)
            nvim('paste', 'bbbbbb', false, 2)
            nvim('paste', 'cccccc', false, 2)
            nvim('paste', 'dddddd', false, 3)
            expect('|aaaaaabbbbbbccccccdddddd|')
          end)
          it('pasting multiple lines', function()
            nvim('paste', 'aaaaaa\n', false, 1)
            nvim('paste', 'bbbbbb\n', false, 2)
            nvim('paste', 'cccccc\n', false, 2)
            nvim('paste', 'dddddd', false, 3)
            expect([[
            |aaaaaa
            bbbbbb
            cccccc
            dddddd|]])
          end)
        end)
        describe('at the end of a line', function()
          before_each(function()
            feed('i||<Esc>')
            -- If nvim_paste() calls :undojoin without making any changes, this makes it an error.
            feed('afoo<Esc>u')
            feed('2|')
          end)
          after_each(function()
            feed('u')
            expect('||')
          end)
          it('pasting one line', function()
            nvim('paste', 'aaaaaa', false, 1)
            nvim('paste', 'bbbbbb', false, 2)
            nvim('paste', 'cccccc', false, 2)
            nvim('paste', 'dddddd', false, 3)
            expect('||aaaaaabbbbbbccccccdddddd')
          end)
          it('pasting multiple lines', function()
            nvim('paste', 'aaaaaa\n', false, 1)
            nvim('paste', 'bbbbbb\n', false, 2)
            nvim('paste', 'cccccc\n', false, 2)
            nvim('paste', 'dddddd', false, 3)
            expect([[
              ||aaaaaa
              bbbbbb
              cccccc
              dddddd]])
          end)
        end)
      end)
      describe('stream: Visual mode', function()
        describe('neither end at the end of a line', function()
          before_each(function()
            feed('i|xxx<CR>xxx|<Esc>')
            -- If nvim_paste() calls :undojoin without making any changes, this makes it an error.
            feed('afoo<Esc>u')
            feed('3|vhk')
          end)
          after_each(function()
            feed('u')
            expect([[
            |xxx
            xxx|]])
          end)
          it('with non-empty chunks', function()
            nvim('paste', 'aaaaaa', false, 1)
            nvim('paste', 'bbbbbb', false, 2)
            nvim('paste', 'cccccc', false, 2)
            nvim('paste', 'dddddd', false, 3)
            expect('|aaaaaabbbbbbccccccdddddd|')
          end)
          it('with empty first chunk', function()
            nvim('paste', '', false, 1)
            nvim('paste', 'bbbbbb', false, 2)
            nvim('paste', 'cccccc', false, 2)
            nvim('paste', 'dddddd', false, 3)
            expect('|bbbbbbccccccdddddd|')
          end)
          it('with all chunks empty', function()
            nvim('paste', '', false, 1)
            nvim('paste', '', false, 2)
            nvim('paste', '', false, 2)
            nvim('paste', '', false, 3)
            expect('||')
          end)
        end)
        describe('cursor at the end of a line', function()
          before_each(function()
            feed('i||xxx<CR>xxx<Esc>')
            -- If nvim_paste() calls :undojoin without making any changes, this makes it an error.
            feed('afoo<Esc>u')
            feed('3|vko')
          end)
          after_each(function()
            feed('u')
            expect([[
              ||xxx
              xxx]])
          end)
          it('with non-empty chunks', function()
            nvim('paste', 'aaaaaa', false, 1)
            nvim('paste', 'bbbbbb', false, 2)
            nvim('paste', 'cccccc', false, 2)
            nvim('paste', 'dddddd', false, 3)
            expect('||aaaaaabbbbbbccccccdddddd')
          end)
          it('with empty first chunk', function()
            nvim('paste', '', false, 1)
            nvim('paste', 'bbbbbb', false, 2)
            nvim('paste', 'cccccc', false, 2)
            nvim('paste', 'dddddd', false, 3)
            expect('||bbbbbbccccccdddddd')
          end)
        end)
        describe('other end at the end of a line', function()
          before_each(function()
            feed('i||xxx<CR>xxx<Esc>')
            -- If nvim_paste() calls :undojoin without making any changes, this makes it an error.
            feed('afoo<Esc>u')
            feed('3|vk')
          end)
          after_each(function()
            feed('u')
            expect([[
              ||xxx
              xxx]])
          end)
          it('with non-empty chunks', function()
            nvim('paste', 'aaaaaa', false, 1)
            nvim('paste', 'bbbbbb', false, 2)
            nvim('paste', 'cccccc', false, 2)
            nvim('paste', 'dddddd', false, 3)
            expect('||aaaaaabbbbbbccccccdddddd')
          end)
          it('with empty first chunk', function()
            nvim('paste', '', false, 1)
            nvim('paste', 'bbbbbb', false, 2)
            nvim('paste', 'cccccc', false, 2)
            nvim('paste', 'dddddd', false, 3)
            expect('||bbbbbbccccccdddddd')
          end)
        end)
      end)
      describe('stream: linewise Visual mode', function()
        before_each(function()
          feed('i123456789<CR>987654321<CR>123456789<Esc>')
          -- If nvim_paste() calls :undojoin without making any changes, this makes it an error.
          feed('afoo<Esc>u')
        end)
        after_each(function()
          feed('u')
          expect([[
            123456789
            987654321
            123456789]])
        end)
        describe('selecting the start of a file', function()
          before_each(function()
            feed('ggV')
          end)
          it('pasting text without final new line', function()
            nvim('paste', 'aaaaaa\n', false, 1)
            nvim('paste', 'bbbbbb\n', false, 2)
            nvim('paste', 'cccccc\n', false, 2)
            nvim('paste', 'dddddd', false, 3)
            expect([[
              aaaaaa
              bbbbbb
              cccccc
              dddddd987654321
              123456789]])
          end)
          it('pasting text with final new line', function()
            nvim('paste', 'aaaaaa\n', false, 1)
            nvim('paste', 'bbbbbb\n', false, 2)
            nvim('paste', 'cccccc\n', false, 2)
            nvim('paste', 'dddddd\n', false, 3)
            expect([[
              aaaaaa
              bbbbbb
              cccccc
              dddddd
              987654321
              123456789]])
          end)
        end)
        describe('selecting the middle of a file', function()
          before_each(function()
            feed('2ggV')
          end)
          it('pasting text without final new line', function()
            nvim('paste', 'aaaaaa\n', false, 1)
            nvim('paste', 'bbbbbb\n', false, 2)
            nvim('paste', 'cccccc\n', false, 2)
            nvim('paste', 'dddddd', false, 3)
            expect([[
              123456789
              aaaaaa
              bbbbbb
              cccccc
              dddddd123456789]])
          end)
          it('pasting text with final new line', function()
            nvim('paste', 'aaaaaa\n', false, 1)
            nvim('paste', 'bbbbbb\n', false, 2)
            nvim('paste', 'cccccc\n', false, 2)
            nvim('paste', 'dddddd\n', false, 3)
            expect([[
              123456789
              aaaaaa
              bbbbbb
              cccccc
              dddddd
              123456789]])
          end)
        end)
        describe('selecting the end of a file', function()
          before_each(function()
            feed('3ggV')
          end)
          it('pasting text without final new line', function()
            nvim('paste', 'aaaaaa\n', false, 1)
            nvim('paste', 'bbbbbb\n', false, 2)
            nvim('paste', 'cccccc\n', false, 2)
            nvim('paste', 'dddddd', false, 3)
            expect([[
              123456789
              987654321
              aaaaaa
              bbbbbb
              cccccc
              dddddd]])
          end)
          it('pasting text with final new line', function()
            nvim('paste', 'aaaaaa\n', false, 1)
            nvim('paste', 'bbbbbb\n', false, 2)
            nvim('paste', 'cccccc\n', false, 2)
            nvim('paste', 'dddddd\n', false, 3)
            expect([[
              123456789
              987654321
              aaaaaa
              bbbbbb
              cccccc
              dddddd
              ]])
          end)
        end)
        describe('selecting the whole file', function()
          before_each(function()
            feed('ggVG')
          end)
          it('pasting text without final new line', function()
            nvim('paste', 'aaaaaa\n', false, 1)
            nvim('paste', 'bbbbbb\n', false, 2)
            nvim('paste', 'cccccc\n', false, 2)
            nvim('paste', 'dddddd', false, 3)
            expect([[
              aaaaaa
              bbbbbb
              cccccc
              dddddd]])
          end)
          it('pasting text with final new line', function()
            nvim('paste', 'aaaaaa\n', false, 1)
            nvim('paste', 'bbbbbb\n', false, 2)
            nvim('paste', 'cccccc\n', false, 2)
            nvim('paste', 'dddddd\n', false, 3)
            expect([[
              aaaaaa
              bbbbbb
              cccccc
              dddddd
              ]])
          end)
        end)
      end)
    end
    describe('without virtualedit,', function()
      run_streamed_paste_tests()
    end)
    describe('with virtualedit=onemore,', function()
      before_each(function()
        command('set virtualedit=onemore')
      end)
      run_streamed_paste_tests()
    end)
    it('non-streaming', function()
      -- With final "\n".
      nvim('paste', 'line 1\nline 2\nline 3\n', true, -1)
      expect([[
        line 1
        line 2
        line 3
        ]])
      eq({0,4,1,0}, funcs.getpos('.'))  -- Cursor follows the paste.
      eq(false, nvim('get_option_value', 'paste', {}))
      command('%delete _')
      -- Without final "\n".
      nvim('paste', 'line 1\nline 2\nline 3', true, -1)
      expect([[
        line 1
        line 2
        line 3]])
      eq({0,3,6,0}, funcs.getpos('.'))
      command('%delete _')
      -- CRLF #10872
      nvim('paste', 'line 1\r\nline 2\r\nline 3\r\n', true, -1)
      expect([[
        line 1
        line 2
        line 3
        ]])
      eq({0,4,1,0}, funcs.getpos('.'))
      command('%delete _')
      -- CRLF without final "\n".
      nvim('paste', 'line 1\r\nline 2\r\nline 3\r', true, -1)
      expect([[
        line 1
        line 2
        line 3
        ]])
      eq({0,4,1,0}, funcs.getpos('.'))
      command('%delete _')
      -- CRLF without final "\r\n".
      nvim('paste', 'line 1\r\nline 2\r\nline 3', true, -1)
      expect([[
        line 1
        line 2
        line 3]])
      eq({0,3,6,0}, funcs.getpos('.'))
      command('%delete _')
      -- Various other junk.
      nvim('paste', 'line 1\r\n\r\rline 2\nline 3\rline 4\r', true, -1)
      expect('line 1\n\n\nline 2\nline 3\nline 4\n')
      eq({0,7,1,0}, funcs.getpos('.'))
      eq(false, nvim('get_option_value', 'paste', {}))
    end)
    it('Replace-mode', function()
      -- Within single line
      nvim('put', {'aabbccdd', 'eeffgghh', 'iijjkkll'}, "c", true, false)
      command('normal l')
      command('startreplace')
      nvim('paste', '123456', true, -1)
      expect([[
      a123456d
      eeffgghh
      iijjkkll]])
      command('%delete _')
      -- Across lines
      nvim('put', {'aabbccdd', 'eeffgghh', 'iijjkkll'}, "c", true, false)
      command('normal l')
      command('startreplace')
      nvim('paste', '123\n456', true, -1)
      expect([[
      a123
      456d
      eeffgghh
      iijjkkll]])
    end)
    it('when searching in Visual mode', function()
      feed('v/')
      nvim('paste', 'aabbccdd', true, -1)
      eq('aabbccdd', funcs.getcmdline())
      expect('')
    end)
    it('mappings are disabled in Cmdline mode', function()
      command('cnoremap a b')
      feed(':')
      nvim('paste', 'a', true, -1)
      eq('a', funcs.getcmdline())
    end)
    it('pasted text is saved in cmdline history when <CR> comes from mapping #20957', function()
      command('cnoremap <CR> <CR>')
      feed(':')
      nvim('paste', 'echo', true, -1)
      eq('', funcs.histget(':'))
      feed('<CR>')
      eq('echo', funcs.histget(':'))
    end)
    it('pasting with empty last chunk in Cmdline mode', function()
      local screen = Screen.new(20, 4)
      screen:attach()
      feed(':')
      nvim('paste', 'Foo', true, 1)
      nvim('paste', '', true, 3)
      screen:expect([[
                            |
        ~                   |
        ~                   |
        :Foo^                |
      ]])
    end)
    it('pasting text with control characters in Cmdline mode', function()
      local screen = Screen.new(20, 4)
      screen:attach()
      feed(':')
      nvim('paste', 'normal! \023\022\006\027', true, -1)
      screen:expect([[
                            |
        ~                   |
        ~                   |
        :normal! ^W^V^F^[^   |
      ]])
    end)
    it('crlf=false does not break lines at CR, CRLF', function()
      nvim('paste', 'line 1\r\n\r\rline 2\nline 3\rline 4\r', false, -1)
      expect('line 1\r\n\r\rline 2\nline 3\rline 4\r')
      eq({0,3,14,0}, funcs.getpos('.'))
    end)
    it('vim.paste() failure', function()
      nvim('exec_lua', 'vim.paste = (function(lines, phase) error("fake fail") end)', {})
      eq('fake fail',
        pcall_err(request, 'nvim_paste', 'line 1\nline 2\nline 3', false, 1))
    end)
  end)

  describe('nvim_put', function()
    it('validation', function()
      eq("Invalid 'line': expected String, got Integer",
        pcall_err(request, 'nvim_put', {42}, 'l', false, false))
      eq("Invalid 'type': 'x'",
        pcall_err(request, 'nvim_put', {'foo'}, 'x', false, false))
    end)
    it("fails if 'nomodifiable'", function()
      command('set nomodifiable')
      eq([[Vim:E21: Cannot make changes, 'modifiable' is off]],
        pcall_err(request, 'nvim_put', {'a','b'}, 'l', true, true))
    end)
    it('inserts text', function()
      -- linewise
      nvim('put', {'line 1','line 2','line 3'}, 'l', true, true)
      expect([[

        line 1
        line 2
        line 3]])
      eq({0,4,1,0}, funcs.getpos('.'))
      command('%delete _')
      -- charwise
      nvim('put', {'line 1','line 2','line 3'}, 'c', true, false)
      expect([[
        line 1
        line 2
        line 3]])
      eq({0,1,1,0}, funcs.getpos('.'))  -- follow=false
      -- blockwise
      nvim('put', {'AA','BB'}, 'b', true, true)
      expect([[
        lAAine 1
        lBBine 2
        line 3]])
      eq({0,2,4,0}, funcs.getpos('.'))
      command('%delete _')
      -- Empty lines list.
      nvim('put', {}, 'c', true, true)
      eq({0,1,1,0}, funcs.getpos('.'))
      expect([[]])
      -- Single empty line.
      nvim('put', {''}, 'c', true, true)
      eq({0,1,1,0}, funcs.getpos('.'))
      expect([[
      ]])
      nvim('put', {'AB'}, 'c', true, true)
      -- after=false, follow=true
      nvim('put', {'line 1','line 2'}, 'c', false, true)
      expect([[
        Aline 1
        line 2B]])
      eq({0,2,7,0}, funcs.getpos('.'))
      command('%delete _')
      nvim('put', {'AB'}, 'c', true, true)
      -- after=false, follow=false
      nvim('put', {'line 1','line 2'}, 'c', false, false)
      expect([[
        Aline 1
        line 2B]])
      eq({0,1,2,0}, funcs.getpos('.'))
      eq('', nvim('eval', 'v:errmsg'))
    end)

    it('detects charwise/linewise text (empty {type})', function()
      -- linewise (final item is empty string)
      nvim('put', {'line 1','line 2','line 3',''}, '', true, true)
      expect([[

        line 1
        line 2
        line 3]])
      eq({0,4,1,0}, funcs.getpos('.'))
      command('%delete _')
      -- charwise (final item is non-empty)
      nvim('put', {'line 1','line 2','line 3'}, '', true, true)
      expect([[
        line 1
        line 2
        line 3]])
      eq({0,3,6,0}, funcs.getpos('.'))
    end)

    it('allows block width', function()
      -- behave consistently with setreg(); support "\022{NUM}" return by getregtype()
      meths.put({'line 1','line 2','line 3'}, 'l', false, false)
      expect([[
        line 1
        line 2
        line 3
        ]])

      -- larger width create spaces
      meths.put({'a', 'bc'}, 'b3', false, false)
      expect([[
        a  line 1
        bc line 2
        line 3
        ]])
      -- smaller width is ignored
      meths.put({'xxx', 'yyy'}, '\0221', false, true)
      expect([[
        xxxa  line 1
        yyybc line 2
        line 3
        ]])
      eq("Invalid 'type': 'bx'",
         pcall_err(meths.put, {'xxx', 'yyy'}, 'bx', false, true))
      eq("Invalid 'type': 'b3x'",
         pcall_err(meths.put, {'xxx', 'yyy'}, 'b3x', false, true))
    end)
  end)

  describe('nvim_strwidth', function()
    it('works', function()
      eq(3, nvim('strwidth', 'abc'))
      -- 6 + (neovim)
      -- 19 * 2 (each japanese character occupies two cells)
      eq(44, nvim('strwidth', 'neovimのデザインかなりまともなのになってる。'))
    end)

    it('cannot handle NULs', function()
      eq(0, nvim('strwidth', '\0abc'))
    end)
  end)

  describe('nvim_get_current_line, nvim_set_current_line', function()
    it('works', function()
      eq('', nvim('get_current_line'))
      nvim('set_current_line', 'abc')
      eq('abc', nvim('get_current_line'))
    end)
  end)

  describe('set/get/del variables', function()
    it('validation', function()
      eq('Key not found: bogus', pcall_err(meths.get_var, 'bogus'))
      eq('Key not found: bogus', pcall_err(meths.del_var, 'bogus'))
    end)

    it('nvim_get_var, nvim_set_var, nvim_del_var', function()
      nvim('set_var', 'lua', {1, 2, {['3'] = 1}})
      eq({1, 2, {['3'] = 1}}, nvim('get_var', 'lua'))
      eq({1, 2, {['3'] = 1}}, nvim('eval', 'g:lua'))
      eq(1, funcs.exists('g:lua'))
      meths.del_var('lua')
      eq(0, funcs.exists('g:lua'))
      eq("Key not found: lua", pcall_err(meths.del_var, 'lua'))
      meths.set_var('lua', 1)

      -- Set locked g: var.
      command('lockvar lua')
      eq('Key is locked: lua', pcall_err(meths.del_var, 'lua'))
      eq('Key is locked: lua', pcall_err(meths.set_var, 'lua', 1))

      exec([[
        function Test()
        endfunction
        function s:Test()
        endfunction
        let g:Unknown_func = function('Test')
        let g:Unknown_script_func = function('s:Test')
      ]])
      eq(NIL, meths.get_var('Unknown_func'))
      eq(NIL, meths.get_var('Unknown_script_func'))

      -- Check if autoload works properly
      local pathsep = helpers.get_pathsep()
      local xconfig = 'Xhome' .. pathsep .. 'Xconfig'
      local xdata = 'Xhome' .. pathsep .. 'Xdata'
      local autoload_folder = table.concat({xconfig, 'nvim', 'autoload'}, pathsep)
      local autoload_file = table.concat({autoload_folder , 'testload.vim'}, pathsep)
      mkdir_p(autoload_folder)
      write_file(autoload_file , [[let testload#value = 2]])

      clear{ args_rm={'-u'}, env={ XDG_CONFIG_HOME=xconfig, XDG_DATA_HOME=xdata } }
      eq(2, meths.get_var('testload#value'))
      rmdir('Xhome')
    end)

    it('nvim_get_vvar, nvim_set_vvar', function()
      -- Set readonly v: var.
      eq('Key is read-only: count',
        pcall_err(request, 'nvim_set_vvar', 'count', 42))
      -- Set writable v: var.
      meths.set_vvar('errmsg', 'set by API')
      eq('set by API', meths.get_vvar('errmsg'))
    end)

    it('vim_set_var returns the old value', function()
      local val1 = {1, 2, {['3'] = 1}}
      local val2 = {4, 7}
      eq(NIL, request('vim_set_var', 'lua', val1))
      eq(val1, request('vim_set_var', 'lua', val2))
    end)

    it('vim_del_var returns the old value', function()
      local val1 = {1, 2, {['3'] = 1}}
      local val2 = {4, 7}
      eq(NIL,  request('vim_set_var', 'lua', val1))
      eq(val1, request('vim_set_var', 'lua', val2))
      eq(val2, request('vim_del_var', 'lua'))
    end)

    it('truncates values with NULs in them', function()
      nvim('set_var', 'xxx', 'ab\0cd')
      eq('ab', nvim('get_var', 'xxx'))
    end)
  end)

  describe('nvim_get_option_value, nvim_set_option_value', function()
    it('works', function()
      ok(nvim('get_option_value', 'equalalways', {}))
      nvim('set_option_value', 'equalalways', false, {})
      ok(not nvim('get_option_value', 'equalalways', {}))
    end)

    it('works to get global value of local options', function()
      eq(false, nvim('get_option_value', 'lisp', {}))
      eq(8, nvim('get_option_value', 'shiftwidth', {}))
    end)

    it('works to set global value of local options', function()
      nvim('set_option_value', 'lisp', true, {scope='global'})
      eq(true, nvim('get_option_value', 'lisp', {scope='global'}))
      eq(false, nvim('get_option_value', 'lisp', {}))
      eq(nil, nvim('command_output', 'setglobal lisp?'):match('nolisp'))
      eq('nolisp', nvim('command_output', 'setlocal lisp?'):match('nolisp'))
      nvim('set_option_value', 'shiftwidth', 20, {scope='global'})
      eq('20', nvim('command_output', 'setglobal shiftwidth?'):match('%d+'))
      eq('8', nvim('command_output', 'setlocal shiftwidth?'):match('%d+'))
    end)

    it('updates where the option was last set from', function()
      nvim('set_option_value', 'equalalways', false, {})
      local status, rv = pcall(nvim, 'command_output',
        'verbose set equalalways?')
      eq(true, status)
      ok(nil ~= string.find(rv, 'noequalalways\n'..
        '\tLast set from API client %(channel id %d+%)'))

      nvim('exec_lua', 'vim.api.nvim_set_option_value("equalalways", true, {})', {})
      status, rv = pcall(nvim, 'command_output',
        'verbose set equalalways?')
      eq(true, status)
      eq('  equalalways\n\tLast set from Lua', rv)
    end)
  end)

  describe('nvim_get_option_value, nvim_set_option_value', function()
    it('works', function()
      ok(nvim('get_option_value', 'equalalways', {}))
      nvim('set_option_value', 'equalalways', false, {})
      ok(not nvim('get_option_value', 'equalalways', {}))
    end)

    it('validation', function()
      eq("Invalid 'scope': expected 'local' or 'global'",
        pcall_err(nvim, 'get_option_value', 'scrolloff', {scope = 'bogus'}))
      eq("Invalid 'scope': expected 'local' or 'global'",
        pcall_err(nvim, 'set_option_value', 'scrolloff', 1, {scope = 'bogus'}))
      eq("Invalid 'scope': expected String, got Integer",
        pcall_err(nvim, 'get_option_value', 'scrolloff', {scope = 42}))
      eq("Invalid 'value': expected Integer/Boolean/String, got Array",
        pcall_err(nvim, 'set_option_value', 'scrolloff', {}, {}))
      eq("Invalid value for option 'scrolloff': expected Number, got Boolean true",
        pcall_err(nvim, 'set_option_value', 'scrolloff', true, {}))
      eq("Invalid value for option 'scrolloff': expected Number, got String \"wrong\"",
        pcall_err(nvim, 'set_option_value', 'scrolloff', 'wrong', {}))
    end)

    it('can get local values when global value is set', function()
      eq(0, nvim('get_option_value', 'scrolloff', {}))
      eq(-1, nvim('get_option_value', 'scrolloff', {scope = 'local'}))
    end)

    it('can set global and local values', function()
      nvim('set_option_value', 'makeprg', 'hello', {})
      eq('hello', nvim('get_option_value', 'makeprg', {}))
      eq('', nvim('get_option_value', 'makeprg', {scope = 'local'}))
      nvim('set_option_value', 'makeprg', 'world', {scope = 'local'})
      eq('world', nvim('get_option_value', 'makeprg', {scope = 'local'}))
      nvim('set_option_value', 'makeprg', 'goodbye', {scope = 'global'})
      eq('goodbye', nvim('get_option_value', 'makeprg', {scope = 'global'}))
      nvim('set_option_value', 'makeprg', 'hello', {})
      eq('hello', nvim('get_option_value', 'makeprg', {scope = 'global'}))
      eq('hello', nvim('get_option_value', 'makeprg', {}))
      eq('', nvim('get_option_value', 'makeprg', {scope = 'local'}))
    end)

    it('clears the local value of an option with nil', function()
      -- Set global value
      nvim('set_option_value', 'shiftwidth', 42, {})
      eq(42, nvim('get_option_value', 'shiftwidth', {}))

      -- Set local value
      nvim('set_option_value', 'shiftwidth', 8, {scope = 'local'})
      eq(8, nvim('get_option_value', 'shiftwidth', {}))
      eq(8, nvim('get_option_value', 'shiftwidth', {scope = 'local'}))
      eq(42, nvim('get_option_value', 'shiftwidth', {scope = 'global'}))

      -- Clear value without scope
      nvim('set_option_value', 'shiftwidth', NIL, {})
      eq(42, nvim('get_option_value', 'shiftwidth', {}))
      eq(42, nvim('get_option_value', 'shiftwidth', {scope = 'local'}))

      -- Clear value with explicit scope
      nvim('set_option_value', 'shiftwidth', 8, {scope = 'local'})
      nvim('set_option_value', 'shiftwidth', NIL, {scope = 'local'})
      eq(42, nvim('get_option_value', 'shiftwidth', {}))
      eq(42, nvim('get_option_value', 'shiftwidth', {scope = 'local'}))

      -- Now try with options with a special "local is unset" value (e.g. 'undolevels')
      nvim('set_option_value', 'undolevels', 1000, {})
      eq(1000, nvim('get_option_value', 'undolevels', {scope = 'local'}))
      nvim('set_option_value', 'undolevels', NIL, {scope = 'local'})
      eq(-123456, nvim('get_option_value', 'undolevels', {scope = 'local'}))

      nvim('set_option_value', 'autoread', true, {})
      eq(true, nvim('get_option_value', 'autoread', {scope = 'local'}))
      nvim('set_option_value', 'autoread', NIL, {scope = 'local'})
      eq(NIL, nvim('get_option_value', 'autoread', {scope = 'local'}))
    end)

    it('set window options', function()
      nvim('set_option_value', 'colorcolumn', '4,3', {})
      eq('4,3', nvim('get_option_value', 'colorcolumn', {scope = 'local'}))
      command("set modified hidden")
      command("enew") -- edit new buffer, window option is preserved
      eq('4,3', nvim('get_option_value', 'colorcolumn', {scope = 'local'}))
    end)

    it('set local window options', function()
      nvim('set_option_value', 'colorcolumn', '4,3', {win=0, scope='local'})
      eq('4,3', nvim('get_option_value', 'colorcolumn', {win = 0, scope = 'local'}))
      command("set modified hidden")
      command("enew") -- edit new buffer, window option is reset
      eq('', nvim('get_option_value', 'colorcolumn', {win = 0, scope = 'local'}))
    end)

    it('get buffer or window-local options', function()
      nvim('command', 'new')
      local buf = nvim('get_current_buf').id
      nvim('set_option_value', 'tagfunc', 'foobar', {buf=buf})
      eq('foobar', nvim('get_option_value', 'tagfunc', {buf = buf}))

      local win = nvim('get_current_win').id
      nvim('set_option_value', 'number', true, {win=win})
      eq(true, nvim('get_option_value', 'number', {win = win}))
    end)

    it('getting current buffer option does not adjust cursor #19381', function()
      nvim('command', 'new')
      local buf = nvim('get_current_buf').id
      local win = nvim('get_current_win').id
      insert('some text')
      feed('0v$')
      eq({1, 9}, nvim('win_get_cursor', win))
      nvim('get_option_value', 'filetype', {buf = buf})
      eq({1, 9}, nvim('win_get_cursor', win))
    end)

    it('can get default option values for filetypes', function()
      command('filetype plugin on')
      for ft, opts in pairs {
        lua = { commentstring = '-- %s' },
        vim = { commentstring = '"%s' },
        man = { tagfunc = 'v:lua.require\'man\'.goto_tag' },
        xml = { formatexpr = 'xmlformat#Format()' }
      } do
        for option, value in pairs(opts) do
          eq(value, nvim('get_option_value', option, { filetype = ft }))
        end
      end

      command'au FileType lua setlocal commentstring=NEW\\ %s'

      eq('NEW %s', nvim('get_option_value', 'commentstring', { filetype = 'lua' }))
    end)

    it('errors for bad FileType autocmds', function()
      command'au FileType lua setlocal commentstring=BAD'
      eq([[FileType Autocommands for "lua": Vim(setlocal):E537: 'commentstring' must be empty or contain %s: commentstring=BAD]],
         pcall_err(nvim, 'get_option_value', 'commentstring', { filetype = 'lua' }))
    end)

  end)

  describe('nvim_{get,set}_current_buf, nvim_list_bufs', function()
    it('works', function()
      eq(1, #nvim('list_bufs'))
      eq(nvim('list_bufs')[1], nvim('get_current_buf'))
      nvim('command', 'new')
      eq(2, #nvim('list_bufs'))
      eq(nvim('list_bufs')[2], nvim('get_current_buf'))
      nvim('set_current_buf', nvim('list_bufs')[1])
      eq(nvim('list_bufs')[1], nvim('get_current_buf'))
    end)
  end)

  describe('nvim_{get,set}_current_win, nvim_list_wins', function()
    it('works', function()
      eq(1, #nvim('list_wins'))
      eq(nvim('list_wins')[1], nvim('get_current_win'))
      nvim('command', 'vsplit')
      nvim('command', 'split')
      eq(3, #nvim('list_wins'))
      eq(nvim('list_wins')[1], nvim('get_current_win'))
      nvim('set_current_win', nvim('list_wins')[2])
      eq(nvim('list_wins')[2], nvim('get_current_win'))
    end)
  end)

  describe('nvim_{get,set}_current_tabpage, nvim_list_tabpages', function()
    it('works', function()
      eq(1, #nvim('list_tabpages'))
      eq(nvim('list_tabpages')[1], nvim('get_current_tabpage'))
      nvim('command', 'tabnew')
      eq(2, #nvim('list_tabpages'))
      eq(2, #nvim('list_wins'))
      eq(nvim('list_wins')[2], nvim('get_current_win'))
      eq(nvim('list_tabpages')[2], nvim('get_current_tabpage'))
      nvim('set_current_win', nvim('list_wins')[1])
      -- Switching window also switches tabpages if necessary
      eq(nvim('list_tabpages')[1], nvim('get_current_tabpage'))
      eq(nvim('list_wins')[1], nvim('get_current_win'))
      nvim('set_current_tabpage', nvim('list_tabpages')[2])
      eq(nvim('list_tabpages')[2], nvim('get_current_tabpage'))
      eq(nvim('list_wins')[2], nvim('get_current_win'))
    end)
  end)

  describe('nvim_get_mode', function()
    it("during normal-mode `g` returns blocking=true", function()
      nvim("input", "o")                -- add a line
      eq({mode='i', blocking=false}, nvim("get_mode"))
      nvim("input", [[<C-\><C-N>]])
      eq(2, nvim("eval", "line('.')"))
      eq({mode='n', blocking=false}, nvim("get_mode"))

      nvim("input", "g")
      eq({mode='n', blocking=true}, nvim("get_mode"))

      nvim("input", "k")                -- complete the operator
      eq(1, nvim("eval", "line('.')"))  -- verify the completed operator
      eq({mode='n', blocking=false}, nvim("get_mode"))
    end)

    it("returns the correct result multiple consecutive times", function()
      for _ = 1,5 do
        eq({mode='n', blocking=false}, nvim("get_mode"))
      end
      nvim("input", "g")
      for _ = 1,4 do
        eq({mode='n', blocking=true}, nvim("get_mode"))
      end
      nvim("input", "g")
      for _ = 1,7 do
        eq({mode='n', blocking=false}, nvim("get_mode"))
      end
    end)

    it("during normal-mode CTRL-W, returns blocking=true", function()
      nvim("input", "<C-W>")
      eq({mode='n', blocking=true}, nvim("get_mode"))

      nvim("input", "s")                  -- complete the operator
      eq(2, nvim("eval", "winnr('$')"))   -- verify the completed operator
      eq({mode='n', blocking=false}, nvim("get_mode"))
    end)

    it("during press-enter prompt without UI returns blocking=false", function()
      eq({mode='n', blocking=false}, nvim("get_mode"))
      command("echom 'msg1'")
      command("echom 'msg2'")
      command("echom 'msg3'")
      command("echom 'msg4'")
      command("echom 'msg5'")
      eq({mode='n', blocking=false}, nvim("get_mode"))
      nvim("input", ":messages<CR>")
      eq({mode='n', blocking=false}, nvim("get_mode"))
    end)

    it("during press-enter prompt returns blocking=true", function()
      nvim("ui_attach", 80, 20, {})
      eq({mode='n', blocking=false}, nvim("get_mode"))
      command("echom 'msg1'")
      command("echom 'msg2'")
      command("echom 'msg3'")
      command("echom 'msg4'")
      command("echom 'msg5'")
      eq({mode='n', blocking=false}, nvim("get_mode"))
      nvim("input", ":messages<CR>")
      eq({mode='r', blocking=true}, nvim("get_mode"))
    end)

    it("during getchar() returns blocking=false", function()
      nvim("input", ":let g:test_input = nr2char(getchar())<CR>")
      -- Events are enabled during getchar(), RPC calls are *not* blocked. #5384
      eq({mode='n', blocking=false}, nvim("get_mode"))
      eq(0, nvim("eval", "exists('g:test_input')"))
      nvim("input", "J")
      eq("J", nvim("eval", "g:test_input"))
      eq({mode='n', blocking=false}, nvim("get_mode"))
    end)

    -- TODO: bug #6247#issuecomment-286403810
    it("batched with input", function()
      nvim("ui_attach", 80, 20, {})
      eq({mode='n', blocking=false}, nvim("get_mode"))
      command("echom 'msg1'")
      command("echom 'msg2'")
      command("echom 'msg3'")
      command("echom 'msg4'")
      command("echom 'msg5'")

      local req = {
        {'nvim_get_mode', {}},
        {'nvim_input',    {':messages<CR>'}},
        {'nvim_get_mode', {}},
        {'nvim_eval',     {'1'}},
      }
      eq({ { {mode='n', blocking=false},
             13,
             {mode='n', blocking=false},  -- TODO: should be blocked=true ?
             1 },
           NIL}, meths.call_atomic(req))
      eq({mode='r', blocking=true}, nvim("get_mode"))
    end)
    it("during insert-mode map-pending, returns blocking=true #6166", function()
      command("inoremap xx foo")
      nvim("input", "ix")
      eq({mode='i', blocking=true}, nvim("get_mode"))
    end)
    it("during normal-mode gU, returns blocking=false #6166", function()
      nvim("input", "gu")
      eq({mode='no', blocking=false}, nvim("get_mode"))
    end)

    it("at '-- More --' prompt returns blocking=true #11899", function()
      command('set more')
      feed(':digraphs<cr>')
      eq({mode='rm', blocking=true}, nvim("get_mode"))
    end)

    it('after <Nop> mapping returns blocking=false #17257', function()
      command('nnoremap <F2> <Nop>')
      feed('<F2>')
      eq({mode='n', blocking=false}, nvim("get_mode"))
    end)

    it('after empty string <expr> mapping returns blocking=false #17257', function()
      command('nnoremap <expr> <F2> ""')
      feed('<F2>')
      eq({mode='n', blocking=false}, nvim("get_mode"))
    end)
  end)

  describe('RPC (K_EVENT)', function()
    it('does not complete ("interrupt") normal-mode operator-pending #6166', function()
      helpers.insert([[
        FIRST LINE
        SECOND LINE]])
      nvim('input', 'gg')
      nvim('input', 'gu')
      -- Make any RPC request (can be non-async: op-pending does not block).
      nvim('get_current_buf')
      -- Buffer should not change.
      expect([[
        FIRST LINE
        SECOND LINE]])
      -- Now send input to complete the operator.
      nvim('input', 'j')
      expect([[
        first line
        second line]])
    end)

    it('does not complete ("interrupt") `d` #3732', function()
      local screen = Screen.new(20, 4)
      screen:attach()
      command('set listchars=eol:$')
      command('set list')
      feed('ia<cr>b<cr>c<cr><Esc>kkk')
      feed('d')
      -- Make any RPC request (can be non-async: op-pending does not block).
      nvim('get_current_buf')
      screen:expect([[
       ^a$                  |
       b$                  |
       c$                  |
                           |
      ]])
    end)

    it('does not complete ("interrupt") normal-mode map-pending #6166', function()
      command("nnoremap dd :let g:foo='it worked...'<CR>")
      helpers.insert([[
        FIRST LINE
        SECOND LINE]])
      nvim('input', 'gg')
      nvim('input', 'd')
      -- Make any RPC request (must be async, because map-pending blocks).
      nvim('get_api_info')
      -- Send input to complete the mapping.
      nvim('input', 'd')
      expect([[
        FIRST LINE
        SECOND LINE]])
      eq('it worked...', helpers.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([[
        FIRST LINE
        SECOND LINE]])
      nvim('input', 'ix')
      -- Make any RPC request (must be async, because map-pending blocks).
      nvim('get_api_info')
      -- Send input to complete the mapping.
      nvim('input', 'x')
      expect([[
        FIRST LINE
        SECOND LINfooE]])
    end)

    it('does not interrupt Insert mode i_CTRL-O #10035', function()
      feed('iHello World<c-o>')
      eq({mode='niI', blocking=false}, meths.get_mode())  -- fast event
      eq(2, eval('1+1'))  -- causes K_EVENT key
      eq({mode='niI', blocking=false}, meths.get_mode())  -- still in ctrl-o mode
      feed('dd')
      eq({mode='i', blocking=false}, meths.get_mode())  -- left ctrl-o mode
      expect('') -- executed the command
    end)

    it('does not interrupt Select mode v_CTRL-O #15688', function()
      feed('iHello World<esc>gh<c-o>')
      eq({mode='vs', blocking=false}, meths.get_mode())  -- fast event
      eq({mode='vs', blocking=false}, meths.get_mode())  -- again #15288
      eq(2, eval('1+1'))  -- causes K_EVENT key
      eq({mode='vs', blocking=false}, meths.get_mode())  -- still in ctrl-o mode
      feed('^')
      eq({mode='s', blocking=false}, meths.get_mode())  -- left ctrl-o mode
      feed('h')
      eq({mode='i', blocking=false}, meths.get_mode())  -- entered insert mode
      expect('h')  -- selection is the whole line and is replaced
    end)

    it('does not interrupt Insert mode i_0_CTRL-D #13997', function()
      command('set timeoutlen=9999')
      feed('i<Tab><Tab>a0')
      eq(2, eval('1+1'))  -- causes K_EVENT key
      feed('<C-D>')
      expect('a')  -- recognized i_0_CTRL-D
    end)

    it("does not interrupt with 'digraph'", function()
      command('set digraph')
      feed('i,')
      eq(2, eval('1+1'))  -- causes K_EVENT key
      feed('<BS>')
      eq(2, eval('1+1'))  -- causes K_EVENT key
      feed('.')
      expect('…')  -- digraph ",." worked
      feed('<Esc>')
      feed(':,')
      eq(2, eval('1+1'))  -- causes K_EVENT key
      feed('<BS>')
      eq(2, eval('1+1'))  -- causes K_EVENT key
      feed('.')
      eq('…', funcs.getcmdline())  -- digraph ",." worked
    end)
  end)

  describe('nvim_get_context', function()
    it('validation', function()
      eq("Invalid key: 'blah'",
        pcall_err(nvim, 'get_context', {blah={}}))
      eq("Invalid 'types': expected Array, got Integer",
        pcall_err(nvim, 'get_context', {types=42}))
      eq("Invalid 'type': 'zub'",
        pcall_err(nvim, 'get_context', {types={'jumps', 'zub', 'zam',}}))
    end)
    it('returns map of current editor state', function()
      local opts = {types={'regs', 'jumps', 'bufs', 'gvars'}}
      eq({}, parse_context(nvim('get_context', {})))

      feed('i1<cr>2<cr>3<c-[>ddddddqahjklquuu')
      feed('gg')
      feed('G')
      command('edit! BUF1')
      command('edit BUF2')
      nvim('set_var', 'one', 1)
      nvim('set_var', 'Two', 2)
      nvim('set_var', 'THREE', 3)

      local expected_ctx = {
        ['regs'] = {
          {['rt'] = 1, ['rc'] = {'1'}, ['n'] = 49, ['ru'] = true},
          {['rt'] = 1, ['rc'] = {'2'}, ['n'] = 50},
          {['rt'] = 1, ['rc'] = {'3'}, ['n'] = 51},
          {['rc'] = {'hjkl'}, ['n'] = 97},
        },

        ['jumps'] = eval(([[
        filter(map(add(
        getjumplist()[0], { 'bufnr': bufnr('%'), 'lnum': getcurpos()[1] }),
        'filter(
        { "f": expand("#".v:val.bufnr.":p"), "l": v:val.lnum },
        { k, v -> k != "l" || v != 1 })'), '!empty(v:val.f)')
        ]]):gsub('\n', '')),

        ['bufs'] = eval([[
        filter(map(getbufinfo(), '{ "f": v:val.name }'), '!empty(v:val.f)')
        ]]),

        ['gvars'] = {{'one', 1}, {'Two', 2}, {'THREE', 3}},
      }

      eq(expected_ctx, parse_context(nvim('get_context', opts)))
      eq(expected_ctx, parse_context(nvim('get_context', {})))
      eq(expected_ctx, parse_context(nvim('get_context', {types={}})))
    end)
  end)

  describe('nvim_load_context', function()
    it('sets current editor state to given context dictionary', function()
      local opts = {types={'regs', 'jumps', 'bufs', 'gvars'}}
      eq({}, parse_context(nvim('get_context', opts)))

      nvim('set_var', 'one', 1)
      nvim('set_var', 'Two', 2)
      nvim('set_var', 'THREE', 3)
      local ctx = nvim('get_context', opts)
      nvim('set_var', 'one', 'a')
      nvim('set_var', 'Two', 'b')
      nvim('set_var', 'THREE', 'c')
      eq({'a', 'b' ,'c'}, eval('[g:one, g:Two, g:THREE]'))
      nvim('load_context', ctx)
      eq({1, 2 ,3}, eval('[g:one, g:Two, g:THREE]'))
    end)
  end)

  describe('nvim_replace_termcodes', function()
    it('escapes K_SPECIAL as K_SPECIAL KS_SPECIAL KE_FILLER', function()
      eq('\128\254X', helpers.nvim('replace_termcodes', '\128', true, true, true))
    end)

    it('leaves non-K_SPECIAL string unchanged', function()
      eq('abc', helpers.nvim('replace_termcodes', 'abc', true, true, true))
    end)

    it('converts <expressions>', function()
      eq('\\', helpers.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.nvim('replace_termcodes',
                                     '<LeftMouse>', true, true, true))
    end)

    it('converts keycodes', function()
      eq('\nx\27x\rx<x', helpers.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.nvim('replace_termcodes',
         '<NL>x<Esc>x<CR>x<lt>x', true, true, false))
    end)

    it('does not crash when transforming an empty string', function()
      -- Actually does not test anything, because current code will use NULL for
      -- an empty string.
      --
      -- Problem here is that if String argument has .data in allocated memory
      -- then `return str` in vim_replace_termcodes body will make Neovim free
      -- `str.data` twice: once when freeing arguments, then when freeing return
      -- value.
      eq('', meths.replace_termcodes('', true, true, true))
    end)
  end)

  describe('nvim_feedkeys', function()
    it('K_SPECIAL escaping', function()
      local function on_setup()
        -- notice the special char(…) \xe2\80\xa6
        nvim('feedkeys', ':let x1="…"\n', '', true)

        -- Both nvim_replace_termcodes and nvim_feedkeys escape \x80
        local inp = helpers.nvim('replace_termcodes', ':let x2="…"<CR>', true, true, true)
        nvim('feedkeys', inp, '', true)   -- escape_ks=true

        -- nvim_feedkeys with K_SPECIAL escaping disabled
        inp = helpers.nvim('replace_termcodes', ':let x3="…"<CR>', true, true, true)
        nvim('feedkeys', inp, '', false)  -- escape_ks=false

        helpers.stop()
      end

      -- spin the loop a bit
      helpers.run(nil, nil, on_setup)

      eq('…', nvim('get_var', 'x1'))
      -- Because of the double escaping this is neq
      neq('…', nvim('get_var', 'x2'))
      eq('…', nvim('get_var', 'x3'))
    end)
  end)

  describe('nvim_out_write', function()
    it('prints long messages correctly #20534', function()
      exec([[
        set more
        redir => g:out
          silent! call nvim_out_write('a')
          silent! call nvim_out_write('a')
          silent! call nvim_out_write('a')
          silent! call nvim_out_write("\n")
          silent! call nvim_out_write('a')
          silent! call nvim_out_write('a')
          silent! call nvim_out_write(repeat('a', 5000) .. "\n")
          silent! call nvim_out_write('a')
          silent! call nvim_out_write('a')
          silent! call nvim_out_write('a')
          silent! call nvim_out_write("\n")
        redir END
      ]])
      eq('\naaa\n' .. ('a'):rep(5002) .. '\naaa', meths.get_var('out'))
    end)

    it('blank line in message works', function()
      local screen = Screen.new(40, 8)
      screen:attach()
      screen:set_default_attr_ids({
        [0] = {bold = true, foreground = Screen.colors.Blue},
        [1] = {bold = true, foreground = Screen.colors.SeaGreen},
        [2] = {bold = true, reverse = true},
      })
      feed([[:call nvim_out_write("\na\n")<CR>]])
      screen:expect{grid=[[
                                                |
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {2:                                        }|
                                                |
        a                                       |
        {1:Press ENTER or type command to continue}^ |
      ]]}
      feed('<CR>')
      feed([[:call nvim_out_write("b\n\nc\n")<CR>]])
      screen:expect{grid=[[
                                                |
        {0:~                                       }|
        {0:~                                       }|
        {2:                                        }|
        b                                       |
                                                |
        c                                       |
        {1:Press ENTER or type command to continue}^ |
      ]]}
    end)
  end)

  describe('nvim_err_write', function()
    local screen

    before_each(function()
      screen = Screen.new(40, 8)
      screen:attach()
      screen:set_default_attr_ids({
        [0] = {bold=true, foreground=Screen.colors.Blue},
        [1] = {foreground = Screen.colors.White, background = Screen.colors.Red},
        [2] = {bold = true, foreground = Screen.colors.SeaGreen},
        [3] = {bold = true, reverse = true},
      })
    end)

    it('can show one line', function()
      nvim_async('err_write', 'has bork\n')
      screen:expect([[
        ^                                        |
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {1:has bork}                                |
      ]])
    end)

    it('shows return prompt when more than &cmdheight lines', function()
      nvim_async('err_write', 'something happened\nvery bad\n')
      screen:expect([[
                                                |
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {3:                                        }|
        {1:something happened}                      |
        {1:very bad}                                |
        {2:Press ENTER or type command to continue}^ |
      ]])
    end)

    it('shows return prompt after all lines are shown', function()
      nvim_async('err_write', 'FAILURE\nERROR\nEXCEPTION\nTRACEBACK\n')
      screen:expect([[
                                                |
        {0:~                                       }|
        {3:                                        }|
        {1:FAILURE}                                 |
        {1:ERROR}                                   |
        {1:EXCEPTION}                               |
        {1:TRACEBACK}                               |
        {2:Press ENTER or type command to continue}^ |
      ]])
    end)

    it('handles multiple calls', function()
      -- without linebreak text is joined to one line
      nvim_async('err_write', 'very ')
      nvim_async('err_write', 'fail\n')
      screen:expect([[
        ^                                        |
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {1:very fail}                               |
      ]])
      helpers.poke_eventloop()

      -- shows up to &cmdheight lines
      nvim_async('err_write', 'more fail\ntoo fail\n')
      screen:expect([[
                                                |
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {3:                                        }|
        {1:more fail}                               |
        {1:too fail}                                |
        {2:Press ENTER or type command to continue}^ |
      ]])
      feed('<cr>')  -- exit the press ENTER screen
    end)
  end)

  describe('nvim_err_writeln', function()
    local screen

    before_each(function()
      screen = Screen.new(40, 8)
      screen:attach()
      screen:set_default_attr_ids({
        [0] = {bold=true, foreground=Screen.colors.Blue},
        [1] = {foreground = Screen.colors.White, background = Screen.colors.Red},
        [2] = {bold = true, foreground = Screen.colors.SeaGreen},
        [3] = {bold = true, reverse = true},
      })
    end)

    it('shows only one return prompt after all lines are shown', function()
      nvim_async('err_writeln', 'FAILURE\nERROR\nEXCEPTION\nTRACEBACK')
      screen:expect([[
                                                |
        {0:~                                       }|
        {3:                                        }|
        {1:FAILURE}                                 |
        {1:ERROR}                                   |
        {1:EXCEPTION}                               |
        {1:TRACEBACK}                               |
        {2:Press ENTER or type command to continue}^ |
      ]])
      feed('<CR>')
      screen:expect([[
        ^                                        |
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
                                                |
      ]])
    end)
  end)

  describe('nvim_list_chans, nvim_get_chan_info', function()
    before_each(function()
      command('autocmd ChanOpen * let g:opened_event = deepcopy(v:event)')
      command('autocmd ChanInfo * let g:info_event = deepcopy(v:event)')
    end)
    local testinfo = {
      stream = 'stdio',
      id = 1,
      mode = 'rpc',
      client = {},
    }
    local stderr = {
      stream = 'stderr',
      id = 2,
      mode = 'bytes',
    }

    it('returns {} for invalid channel', function()
      eq({}, meths.get_chan_info(0))
      eq({}, meths.get_chan_info(-1))
      -- more preallocated numbers might be added, try something high
      eq({}, meths.get_chan_info(10))
    end)

    it('stream=stdio channel', function()
      eq({[1]=testinfo,[2]=stderr}, meths.list_chans())
      eq(testinfo, meths.get_chan_info(1))
      eq(stderr, meths.get_chan_info(2))

      meths.set_client_info("functionaltests",
                            {major=0, minor=3, patch=17},
                            'ui',
                            {do_stuff={n_args={2,3}}},
                            {license= 'Apache2'})
      local info = {
        stream = 'stdio',
        id = 1,
        mode = 'rpc',
        client = {
          name='functionaltests',
          version={major=0, minor=3, patch=17},
          type='ui',
          methods={do_stuff={n_args={2,3}}},
          attributes={license='Apache2'},
        },
      }
      eq({info=info}, meths.get_var("info_event"))
      eq({[1]=info, [2]=stderr}, meths.list_chans())
      eq(info, meths.get_chan_info(1))
    end)

    it('stream=job channel', function()
      eq(3, eval("jobstart(['cat'], {'rpc': v:true})"))
      local catpath = eval('exepath("cat")')
      local info = {
        stream='job',
        id=3,
        argv={ catpath },
        mode='rpc',
        client={},
      }
      eq({info=info}, meths.get_var("opened_event"))
      eq({[1]=testinfo,[2]=stderr,[3]=info}, meths.list_chans())
      eq(info, meths.get_chan_info(3))
      eval('rpcrequest(3, "nvim_set_client_info", "amazing-cat", {}, "remote",'..
                       '{"nvim_command":{"n_args":1}},'.. -- and so on
                       '{"description":"The Amazing Cat"})')
      info = {
        stream='job',
        id=3,
        argv={ catpath },
        mode='rpc',
        client = {
          name='amazing-cat',
          version={major=0},
          type='remote',
          methods={nvim_command={n_args=1}},
          attributes={description="The Amazing Cat"},
        },
      }
      eq({info=info}, meths.get_var("info_event"))
      eq({[1]=testinfo,[2]=stderr,[3]=info}, meths.list_chans())

      eq("Vim:Error invoking 'nvim_set_current_buf' on channel 3 (amazing-cat):\nWrong type for argument 1 when calling nvim_set_current_buf, expecting Buffer",
         pcall_err(eval, 'rpcrequest(3, "nvim_set_current_buf", -1)'))
    end)

    it('stream=job :terminal channel', function()
      command(':terminal')
      eq({id=1}, meths.get_current_buf())
      eq(3, meths.get_option_value('channel', {buf=1}))

      local info = {
        stream='job',
        id=3,
        argv={ eval('exepath(&shell)') },
        mode='terminal',
        buffer = 1,
        pty='?',
      }
      local event = meths.get_var("opened_event")
      if not is_os('win') then
        info.pty = event.info.pty
        neq(nil, string.match(info.pty, "^/dev/"))
      end
      eq({info=info}, event)
      info.buffer = {id=1}
      eq({[1]=testinfo,[2]=stderr,[3]=info}, meths.list_chans())
      eq(info, meths.get_chan_info(3))

      -- :terminal with args + running process.
      command(':exe "terminal" shellescape(v:progpath) "-u NONE -i NONE"')
      eq(-1, eval('jobwait([&channel], 0)[0]'))  -- Running?
      local expected2 = {
        stream = 'job',
        id = 4,
        argv = (
          is_os('win') and {
            eval('&shell'),
            '/s',
            '/c',
            fmt('"%s -u NONE -i NONE"', eval('shellescape(v:progpath)')),
          } or {
            eval('&shell'),
            eval('&shellcmdflag'),
            fmt('%s -u NONE -i NONE', eval('shellescape(v:progpath)')),
          }
        ),
        mode = 'terminal',
        buffer = 2,
        pty = '?',
      }
      local actual2 = eval('nvim_get_chan_info(&channel)')
      expected2.pty = actual2.pty
      eq(expected2, actual2)

      -- :terminal with args + stopped process.
      eq(1, eval('jobstop(&channel)'))
      eval('jobwait([&channel], 1000)')  -- Wait.
      expected2.pty = (is_os('win') and '?' or '')  -- pty stream was closed.
      eq(expected2, eval('nvim_get_chan_info(&channel)'))
    end)
  end)

  describe('nvim_call_atomic', function()
    it('works', function()
      meths.buf_set_lines(0, 0, -1, true, {'first'})
      local req = {
        {'nvim_get_current_line', {}},
        {'nvim_set_current_line', {'second'}},
      }
      eq({{'first', NIL}, NIL}, meths.call_atomic(req))
      eq({'second'}, meths.buf_get_lines(0, 0, -1, true))
    end)

    it('allows multiple return values', function()
      local req = {
        {'nvim_set_var', {'avar', true}},
        {'nvim_set_var', {'bvar', 'string'}},
        {'nvim_get_var', {'avar'}},
        {'nvim_get_var', {'bvar'}},
      }
      eq({{NIL, NIL, true, 'string'}, NIL}, meths.call_atomic(req))
    end)

    it('is aborted by errors in call', function()
      local error_types = meths.get_api_info()[2].error_types
      local req = {
        {'nvim_set_var', {'one', 1}},
        {'nvim_buf_set_lines', {}},
        {'nvim_set_var', {'two', 2}},
      }
      eq({{NIL}, {1, error_types.Exception.id,
                  'Wrong number of arguments: expecting 5 but got 0'}},
         meths.call_atomic(req))
      eq(1, meths.get_var('one'))
      eq(false, pcall(meths.get_var, 'two'))

      -- still returns all previous successful calls
      req = {
        {'nvim_set_var', {'avar', 5}},
        {'nvim_set_var', {'bvar', 'string'}},
        {'nvim_get_var', {'avar'}},
        {'nvim_buf_get_lines', {0, 10, 20, true}},
        {'nvim_get_var', {'bvar'}},
      }
      eq({{NIL, NIL, 5}, {3, error_types.Validation.id, 'Index out of bounds'}},
        meths.call_atomic(req))

      req = {
        {'i_am_not_a_method', {'xx'}},
        {'nvim_set_var', {'avar', 10}},
      }
      eq({{}, {0, error_types.Exception.id, 'Invalid method: i_am_not_a_method'}},
         meths.call_atomic(req))
      eq(5, meths.get_var('avar'))
    end)

    it('validation', function()
      local req = {
        {'nvim_set_var', {'avar', 1}},
        {'nvim_set_var'},
        {'nvim_set_var', {'avar', 2}},
      }
      eq("Invalid 'calls' item: expected 2-item Array",
         pcall_err(meths.call_atomic, req))
      -- call before was done, but not after
      eq(1, meths.get_var('avar'))

      req = {
        { 'nvim_set_var', { 'bvar', { 2, 3 } } },
        12,
      }
      eq("Invalid 'calls' item: expected Array, got Integer",
         pcall_err(meths.call_atomic, req))
      eq({2,3}, meths.get_var('bvar'))

      req = {
        {'nvim_set_current_line', 'little line'},
        {'nvim_set_var', {'avar', 3}},
      }
      eq("Invalid call args: expected Array, got String",
         pcall_err(meths.call_atomic, req))
      -- call before was done, but not after
      eq(1, meths.get_var('avar'))
      eq({''}, meths.buf_get_lines(0, 0, -1, true))
    end)
  end)

  describe('nvim_list_runtime_paths', function()
    setup(function()
      local pathsep = helpers.get_pathsep()
      mkdir_p('Xtest'..pathsep..'a')
      mkdir_p('Xtest'..pathsep..'b')
    end)
    teardown(function()
      rmdir 'Xtest'
    end)
    before_each(function()
      meths.set_current_dir 'Xtest'
    end)

    it('returns nothing with empty &runtimepath', function()
      meths.set_option_value('runtimepath', '', {})
      eq({}, meths.list_runtime_paths())
    end)
    it('returns single runtimepath', function()
      meths.set_option_value('runtimepath', 'a', {})
      eq({'a'}, meths.list_runtime_paths())
    end)
    it('returns two runtimepaths', function()
      meths.set_option_value('runtimepath', 'a,b', {})
      eq({'a', 'b'}, meths.list_runtime_paths())
    end)
    it('returns empty strings when appropriate', function()
      meths.set_option_value('runtimepath', 'a,,b', {})
      eq({'a', '', 'b'}, meths.list_runtime_paths())
      meths.set_option_value('runtimepath', ',a,b', {})
      eq({'', 'a', 'b'}, meths.list_runtime_paths())
      -- Trailing "," is ignored. Use ",," if you really really want CWD.
      meths.set_option_value('runtimepath', 'a,b,', {})
      eq({'a', 'b'}, meths.list_runtime_paths())
      meths.set_option_value('runtimepath', 'a,b,,', {})
      eq({'a', 'b', ''}, meths.list_runtime_paths())
    end)
    it('truncates too long paths', function()
      local long_path = ('/a'):rep(8192)
      meths.set_option_value('runtimepath', long_path, {})
      local paths_list = meths.list_runtime_paths()
      eq({}, paths_list)
    end)
  end)

  it('can throw exceptions', function()
    local status, err = pcall(nvim, 'get_option_value', 'invalid-option', {})
    eq(false, status)
    ok(err:match("Invalid 'option': 'invalid%-option'") ~= nil)
  end)

  it('does not truncate error message <1 MB #5984', function()
    local very_long_name = 'A'..('x'):rep(10000)..'Z'
    local status, err = pcall(nvim, 'get_option_value', very_long_name, {})
    eq(false, status)
    eq(very_long_name, err:match('Ax+Z?'))
  end)

  it("does not leak memory on incorrect argument types", function()
    local status, err = pcall(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)
  end)

  describe('nvim_parse_expression', function()
    before_each(function()
      meths.set_option_value('isident', '', {})
    end)

    local function simplify_east_api_node(line, east_api_node)
      if east_api_node == NIL then
        return nil
      end
      if east_api_node.children then
        for k, v in pairs(east_api_node.children) do
          east_api_node.children[k] = simplify_east_api_node(line, v)
        end
      end
      local typ = east_api_node.type
      if typ == 'Register' then
        typ = typ .. ('(name=%s)'):format(
          tostring(intchar2lua(east_api_node.name)))
        east_api_node.name = nil
      elseif typ == 'PlainIdentifier' then
        typ = typ .. ('(scope=%s,ident=%s)'):format(
          tostring(intchar2lua(east_api_node.scope)), east_api_node.ident)
        east_api_node.scope = nil
        east_api_node.ident = nil
      elseif typ == 'PlainKey' then
        typ = typ .. ('(key=%s)'):format(east_api_node.ident)
        east_api_node.ident = nil
      elseif typ == 'Comparison' then
        typ = typ .. ('(type=%s,inv=%u,ccs=%s)'):format(
          east_api_node.cmp_type, east_api_node.invert and 1 or 0,
          east_api_node.ccs_strategy)
        east_api_node.ccs_strategy = nil
        east_api_node.cmp_type = nil
        east_api_node.invert = nil
      elseif typ == 'Integer' then
        typ = typ .. ('(val=%u)'):format(east_api_node.ivalue)
        east_api_node.ivalue = nil
      elseif typ == 'Float' then
        typ = typ .. format_string('(val=%e)', east_api_node.fvalue)
        east_api_node.fvalue = nil
      elseif typ == 'SingleQuotedString' or typ == 'DoubleQuotedString' then
        typ = format_string('%s(val=%q)', typ, east_api_node.svalue)
        east_api_node.svalue = nil
      elseif typ == 'Option' then
        typ = ('%s(scope=%s,ident=%s)'):format(
          typ,
          tostring(intchar2lua(east_api_node.scope)),
          east_api_node.ident)
        east_api_node.ident = nil
        east_api_node.scope = nil
      elseif typ == 'Environment' then
        typ = ('%s(ident=%s)'):format(typ, east_api_node.ident)
        east_api_node.ident = nil
      elseif typ == 'Assignment' then
        local aug = east_api_node.augmentation
        if aug == '' then aug = 'Plain' end
        typ = ('%s(%s)'):format(typ, aug)
        east_api_node.augmentation = nil
      end
      typ = ('%s:%u:%u:%s'):format(
        typ, east_api_node.start[1], east_api_node.start[2],
        line:sub(east_api_node.start[2] + 1,
                 east_api_node.start[2] + 1 + east_api_node.len - 1))
      assert(east_api_node.start[2] + east_api_node.len - 1 <= #line)
      for k, _ in pairs(east_api_node.start) do
        assert(({true, true})[k])
      end
      east_api_node.start = nil
      east_api_node.type = nil
      east_api_node.len = nil
      local can_simplify = true
      for _, _ in pairs(east_api_node) do
        if can_simplify then can_simplify = false end
      end
      if can_simplify then
        return typ
      else
        east_api_node[1] = typ
        return east_api_node
      end
    end
    local function simplify_east_api(line, east_api)
      if east_api.error then
        east_api.err = east_api.error
        east_api.error = nil
        east_api.err.msg = east_api.err.message
        east_api.err.message = nil
      end
      if east_api.ast then
        east_api.ast = {simplify_east_api_node(line, east_api.ast)}
        if #east_api.ast == 0 then
          east_api.ast = nil
        end
      end
      if east_api.len == #line then
        east_api.len = nil
      end
      return east_api
    end
    local function simplify_east_hl(line, east_hl)
      for i, v in ipairs(east_hl) do
        east_hl[i] = ('%s:%u:%u:%s'):format(
          v[4],
          v[1],
          v[2],
          line:sub(v[2] + 1, v[3]))
      end
      return east_hl
    end
    local FLAGS_TO_STR = {
      [0] = "",
      [1] = "m",
      [2] = "E",
      [3] = "mE",
      [4] = "l",
      [5] = "lm",
      [6] = "lE",
      [7] = "lmE",
    }
    local function _check_parsing(opts, str, exp_ast, exp_highlighting_fs,
                                  nz_flags_exps)
      if type(str) ~= 'string' then
        return
      end
      local zflags = opts.flags[1]
      nz_flags_exps = nz_flags_exps or {}
      for _, flags in ipairs(opts.flags) do
        local err, msg = pcall(function()
          local east_api = meths.parse_expression(str, FLAGS_TO_STR[flags], true)
          local east_hl = east_api.highlight
          east_api.highlight = nil
          local ast = simplify_east_api(str, east_api)
          local hls = simplify_east_hl(str, east_hl)
          local exps = {
            ast = exp_ast,
            hl_fs = exp_highlighting_fs,
          }
          local add_exps = nz_flags_exps[flags]
          if not add_exps and flags == 3 + zflags then
            add_exps = nz_flags_exps[1 + zflags] or nz_flags_exps[2 + zflags]
          end
          if add_exps then
            if add_exps.ast then
              exps.ast = mergedicts_copy(exps.ast, add_exps.ast)
            end
            if add_exps.hl_fs then
              exps.hl_fs = mergedicts_copy(exps.hl_fs, add_exps.hl_fs)
            end
          end
          eq(exps.ast, ast)
          if exp_highlighting_fs then
            local exp_highlighting = {}
            local next_col = 0
            for i, h in ipairs(exps.hl_fs) do
              exp_highlighting[i], next_col = h(next_col)
            end
            eq(exp_highlighting, hls)
          end
        end)
        if not err then
          if type(msg) == 'table' then
            local merr, new_msg = pcall(
              format_string, 'table error:\n%s\n\n(%r)', msg.message, msg)
            if merr then
              msg = new_msg
            else
              msg = format_string('table error without .message:\n(%r)',
                                  msg)
            end
          elseif type(msg) ~= 'string' then
            msg = format_string('non-string non-table error:\n%r', msg)
          end
          error(format_string('Error while processing test (%r, %s):\n%s',
                              str, FLAGS_TO_STR[flags], msg))
        end
      end
    end
    local function hl(group, str, shift)
      return function(next_col)
        local col = next_col + (shift or 0)
        return (('%s:%u:%u:%s'):format(
          'Nvim' .. group,
          0,
          col,
          str)), (col + #str)
      end
    end
    local function fmtn(typ, args, rest)
      if (typ == 'UnknownFigure'
          or typ == 'DictLiteral'
          or typ == 'CurlyBracesIdentifier'
          or typ == 'Lambda') then
        return ('%s%s'):format(typ, rest)
      elseif typ == 'DoubleQuotedString' or typ == 'SingleQuotedString' then
        if args:sub(-4) == 'NULL' then
          args = args:sub(1, -5) .. '""'
        end
        return ('%s(%s)%s'):format(typ, args, rest)
      end
    end
    require('test.unit.viml.expressions.parser_tests')(
        it, _check_parsing, hl, fmtn)
  end)

  describe('nvim_list_uis', function()
    it('returns empty if --headless', function()
      -- Test runner defaults to --headless.
      eq({}, nvim("list_uis"))
    end)
    it('returns attached UIs', function()
      local screen = Screen.new(20, 4)
      screen:attach({override=true})
      local expected = {
        {
          chan = 1,
          ext_cmdline = false,
          ext_hlstate = false,
          ext_linegrid = screen._options.ext_linegrid or false,
          ext_messages = false,
          ext_multigrid = false,
          ext_popupmenu = false,
          ext_tabline = false,
          ext_termcolors = false,
          ext_wildmenu = false,
          height = 4,
          override = true,
          rgb = true,
          stdin_tty = false,
          stdout_tty = false,
          term_background = '',
          term_colors = 0,
          term_name = '',
          width = 20,
        }
      }

      eq(expected, nvim("list_uis"))

      screen:detach()
      screen = Screen.new(44, 99)
      screen:attach({ rgb = false })
      expected[1].rgb = false
      expected[1].override = false
      expected[1].width = 44
      expected[1].height = 99
      eq(expected, nvim("list_uis"))
    end)
  end)

  describe('nvim_create_namespace', function()
    it('works', function()
      eq({}, meths.get_namespaces())
      eq(1, meths.create_namespace("ns-1"))
      eq(2, meths.create_namespace("ns-2"))
      eq(1, meths.create_namespace("ns-1"))
      eq({["ns-1"]=1, ["ns-2"]=2}, meths.get_namespaces())
      eq(3, meths.create_namespace(""))
      eq(4, meths.create_namespace(""))
      eq({["ns-1"]=1, ["ns-2"]=2}, meths.get_namespaces())
    end)
  end)

  describe('nvim_create_buf', function()
    it('works', function()
      eq({id=2}, meths.create_buf(true, false))
      eq({id=3}, meths.create_buf(false, false))
      eq('  1 %a   "[No Name]"                    line 1\n'..
         '  2  h   "[No Name]"                    line 0',
         meths.command_output("ls"))
      -- current buffer didn't change
      eq({id=1}, meths.get_current_buf())

      local screen = Screen.new(20, 4)
      screen:attach()
      meths.buf_set_lines(2, 0, -1, true, {"some text"})
      meths.set_current_buf(2)
      screen:expect([[
        ^some text           |
        {1:~                   }|
        {1:~                   }|
                            |
      ]], {
        [1] = {bold = true, foreground = Screen.colors.Blue1},
      })
    end)

    it('can change buftype before visiting', function()
      meths.set_option_value("hidden", false, {})
      eq({id=2}, meths.create_buf(true, false))
      meths.set_option_value("buftype", "nofile", {buf=2})
      meths.buf_set_lines(2, 0, -1, true, {"test text"})
      command("split | buffer 2")
      eq({id=2}, meths.get_current_buf())
      -- if the buf_set_option("buftype") didn't work, this would error out.
      command("close")
      eq({id=1}, meths.get_current_buf())
    end)

    it("does not trigger BufEnter, BufWinEnter", function()
      command("let g:fired = v:false")
      command("au BufEnter,BufWinEnter * let g:fired = v:true")

      eq({id=2}, meths.create_buf(true, false))
      meths.buf_set_lines(2, 0, -1, true, {"test", "text"})

      eq(false, eval('g:fired'))
    end)

    it('scratch-buffer', function()
      eq({id=2}, meths.create_buf(false, true))
      eq({id=3}, meths.create_buf(true, true))
      eq({id=4}, meths.create_buf(true, true))
      local scratch_bufs = { 2, 3, 4 }
      eq('  1 %a   "[No Name]"                    line 1\n'..
         '  3  h   "[Scratch]"                    line 0\n'..
         '  4  h   "[Scratch]"                    line 0',
         exec_capture('ls'))
      -- current buffer didn't change
      eq({id=1}, meths.get_current_buf())

      local screen = Screen.new(20, 4)
      screen:set_default_attr_ids({
        [1] = {bold = true, foreground = Screen.colors.Blue1},
      })
      screen:attach()

      --
      -- Editing a scratch-buffer does NOT change its properties.
      --
      local edited_buf = 2
      meths.buf_set_lines(edited_buf, 0, -1, true, {"some text"})
      for _,b in ipairs(scratch_bufs) do
        eq('nofile', meths.get_option_value('buftype', {buf=b}))
        eq('hide', meths.get_option_value('bufhidden', {buf=b}))
        eq(false, meths.get_option_value('swapfile', {buf=b}))
        eq(false, meths.get_option_value('modeline', {buf=b}))
      end

      --
      -- Visiting a scratch-buffer DOES NOT change its properties.
      --
      meths.set_current_buf(edited_buf)
      screen:expect([[
        ^some text           |
        {1:~                   }|
        {1:~                   }|
                            |
      ]])
      eq('nofile', meths.get_option_value('buftype', {buf=edited_buf}))
      eq('hide', meths.get_option_value('bufhidden', {buf=edited_buf}))
      eq(false, meths.get_option_value('swapfile', {buf=edited_buf}))
      eq(false, meths.get_option_value('modeline', {buf=edited_buf}))

      -- Scratch buffer can be wiped without error.
      command('bwipe')
      screen:expect([[
        ^                    |
        {1:~                   }|
        {1:~                   }|
                            |
      ]])
    end)

    it('does not cause heap-use-after-free on exit while setting options', function()
      command('au OptionSet * q')
      expect_exit(command, 'silent! call nvim_create_buf(0, 1)')
    end)
  end)

  describe('nvim_get_runtime_file', function()
    local p = helpers.alter_slashes
    it('can find files', function()
      eq({}, meths.get_runtime_file("bork.borkbork", false))
      eq({}, meths.get_runtime_file("bork.borkbork", true))
      eq(1, #meths.get_runtime_file("autoload/msgpack.vim", false))
      eq(1, #meths.get_runtime_file("autoload/msgpack.vim", true))
      local val = meths.get_runtime_file("autoload/remote/*.vim", true)
      eq(2, #val)
      if endswith(val[1], "define.vim") then
        ok(endswith(val[1], p"autoload/remote/define.vim"))
        ok(endswith(val[2], p"autoload/remote/host.vim"))
      else
        ok(endswith(val[1], p"autoload/remote/host.vim"))
        ok(endswith(val[2], p"autoload/remote/define.vim"))
      end
      val = meths.get_runtime_file("autoload/remote/*.vim", false)
      eq(1, #val)
      ok(endswith(val[1], p"autoload/remote/define.vim")
         or endswith(val[1], p"autoload/remote/host.vim"))

      val = meths.get_runtime_file("lua", true)
      eq(1, #val)
      ok(endswith(val[1], p"lua"))

      val = meths.get_runtime_file("lua/vim", true)
      eq(1, #val)
      ok(endswith(val[1], p"lua/vim"))
    end)

    it('can find directories', function()
      local val = meths.get_runtime_file("lua/", true)
      eq(1, #val)
      ok(endswith(val[1], p"lua/"))

      val = meths.get_runtime_file("lua/vim/", true)
      eq(1, #val)
      ok(endswith(val[1], p"lua/vim/"))

      eq({}, meths.get_runtime_file("foobarlang/", true))
    end)
    it('can handle bad patterns', function()
      skip(is_os('win'))

      eq("Vim:E220: Missing }.", pcall_err(meths.get_runtime_file, "{", false))

      eq('Vim(echo):E5555: API call: Vim:E220: Missing }.',
        exc_exec("echo nvim_get_runtime_file('{', v:false)"))
    end)
  end)

  describe('nvim_get_all_options_info', function()
    it('should have key value pairs of option names', function()
      local options_info = meths.get_all_options_info()
      neq(nil, options_info.listchars)
      neq(nil, options_info.tabstop)

      eq(meths.get_option_info'winhighlight', options_info.winhighlight)
    end)

    it('should not crash when echoed', function()
      meths.exec2("echo nvim_get_all_options_info()", { output = true })
    end)
  end)

  describe('nvim_get_option_info', function()
    it('should error for unknown options', function()
      eq("Invalid option (not found): 'bogus'", pcall_err(meths.get_option_info, 'bogus'))
    end)

    it('should return the same options for short and long name', function()
      eq(meths.get_option_info'winhl', meths.get_option_info'winhighlight')
    end)

    it('should have information about window options', function()
      eq({
        allows_duplicates = false,
        commalist = true;
        default = "";
        flaglist = false;
        global_local = false;
        last_set_chan = 0;
        last_set_linenr = 0;
        last_set_sid = 0;
        name = "winhighlight";
        scope = "win";
        shortname = "winhl";
        type = "string";
        was_set = false;
      }, meths.get_option_info'winhl')
    end)

    it('should have information about buffer options', function()
      eq({
        allows_duplicates = true,
        commalist = false,
        default = "",
        flaglist = false,
        global_local = false,
        last_set_chan = 0,
        last_set_linenr = 0,
        last_set_sid = 0,
        name = "filetype",
        scope = "buf",
        shortname = "ft",
        type = "string",
        was_set = false
      }, meths.get_option_info'filetype')
    end)

    it('should have information about global options', function()
      -- precondition: the option was changed from its default
      -- in test setup.
      eq(false, meths.get_option_value('showcmd', {}))

      eq({
        allows_duplicates = true,
        commalist = false,
        default = true,
        flaglist = false,
        global_local = false,
        last_set_chan = 0,
        last_set_linenr = 0,
        last_set_sid = -2,
        name = "showcmd",
        scope = "global",
        shortname = "sc",
        type = "boolean",
        was_set = true
      }, meths.get_option_info'showcmd')

      meths.set_option_value('showcmd', true, {})

      eq({
        allows_duplicates = true,
        commalist = false,
        default = true,
        flaglist = false,
        global_local = false,
        last_set_chan = 1,
        last_set_linenr = 0,
        last_set_sid = -9,
        name = "showcmd",
        scope = "global",
        shortname = "sc",
        type = "boolean",
        was_set = true
      }, meths.get_option_info'showcmd')
    end)
  end)

  describe('nvim_get_option_info2', function()
    local fname
    local bufs
    local wins

    before_each(function()
      fname = tmpname()
      write_file(fname, [[
        setglobal dictionary=mydict " 1, global-local (buffer)
        setlocal  formatprg=myprg   " 2, global-local (buffer)
        setglobal equalprg=prg1     " 3, global-local (buffer)
        setlocal  equalprg=prg2     " 4, global-local (buffer)
        setglobal fillchars=stl:x   " 5, global-local (window)
        setlocal  listchars=eol:c   " 6, global-local (window)
        setglobal showbreak=aaa     " 7, global-local (window)
        setlocal  showbreak=bbb     " 8, global-local (window)
        setglobal completeopt=menu  " 9, global
      ]])

      exec_lua 'vim.cmd.vsplit()'
      meths.create_buf(false, false)

      bufs = meths.list_bufs()
      wins = meths.list_wins()

      meths.win_set_buf(wins[1].id, bufs[1].id)
      meths.win_set_buf(wins[2].id, bufs[2].id)

      meths.set_current_win(wins[2].id)
      meths.exec('source ' .. fname, false)

      meths.set_current_win(wins[1].id)
    end)

    after_each(function()
      os.remove(fname)
    end)

    it('should return option information', function()
      eq(meths.get_option_info('dictionary'),  meths.get_option_info2('dictionary',  {})) -- buffer
      eq(meths.get_option_info('fillchars'),   meths.get_option_info2('fillchars',   {})) -- window
      eq(meths.get_option_info('completeopt'), meths.get_option_info2('completeopt', {})) -- global
    end)

    describe('last set', function()
      local tests = {
        {desc="(buf option, global requested, global set) points to global",   linenr=1, sid=1, args={'dictionary', {scope='global'}}},
        {desc="(buf option, global requested, local set) is not set",          linenr=0, sid=0, args={'formatprg',  {scope='global'}}},
        {desc="(buf option, global requested, both set) points to global",     linenr=3, sid=1, args={'equalprg',   {scope='global'}}},
        {desc="(buf option, local requested, global set) is not set",          linenr=0, sid=0, args={'dictionary', {scope='local'}}},
        {desc="(buf option, local requested, local set) points to local",      linenr=2, sid=1, args={'formatprg',  {scope='local'}}},
        {desc="(buf option, local requested, both set) points to local",       linenr=4, sid=1, args={'equalprg',   {scope='local'}}},
        {desc="(buf option, fallback requested, global set) points to global", linenr=1, sid=1, args={'dictionary', {}}},
        {desc="(buf option, fallback requested, local set) points to local",   linenr=2, sid=1, args={'formatprg',  {}}},
        {desc="(buf option, fallback requested, both set) points to local",    linenr=4, sid=1, args={'equalprg',   {}}},
        {desc="(win option, global requested, global set) points to global",   linenr=5, sid=1, args={'fillchars', {scope='global'}}},
        {desc="(win option, global requested, local set) is not set",          linenr=0, sid=0, args={'listchars', {scope='global'}}},
        {desc="(win option, global requested, both set) points to global",     linenr=7, sid=1, args={'showbreak', {scope='global'}}},
        {desc="(win option, local requested, global set) is not set",          linenr=0, sid=0, args={'fillchars', {scope='local'}}},
        {desc="(win option, local requested, local set) points to local",      linenr=6, sid=1, args={'listchars', {scope='local'}}},
        {desc="(win option, local requested, both set) points to local",       linenr=8, sid=1, args={'showbreak', {scope='local'}}},
        {desc="(win option, fallback requested, global set) points to global", linenr=5, sid=1, args={'fillchars', {}}},
        {desc="(win option, fallback requested, local set) points to local",   linenr=6, sid=1, args={'listchars', {}}},
        {desc="(win option, fallback requested, both set) points to local",    linenr=8, sid=1, args={'showbreak', {}}},
        {desc="(global option, global requested) points to global",            linenr=9, sid=1, args={'completeopt', {scope='global'}}},
        {desc="(global option, local requested) is not set",                   linenr=0, sid=0, args={'completeopt', {scope='local'}}},
        {desc="(global option, fallback requested) points to global",          linenr=9, sid=1, args={'completeopt', {}}},
      }

      for _, t in pairs(tests) do
        it(t.desc, function()
          -- Switch to the target buffer/window so that curbuf/curwin are used.
          meths.set_current_win(wins[2].id)
          local info = meths.get_option_info2(unpack(t.args))
          eq(t.linenr, info.last_set_linenr)
          eq(t.sid, info.last_set_sid)
        end)
      end

      it('is provided for cross-buffer requests', function()
        local info = meths.get_option_info2('formatprg', {buf=bufs[2].id})
        eq(2, info.last_set_linenr)
        eq(1, info.last_set_sid)
      end)

      it('is provided for cross-window requests', function()
        local info = meths.get_option_info2('listchars', {win=wins[2].id})
        eq(6, info.last_set_linenr)
        eq(1, info.last_set_sid)
      end)
    end)
  end)

  describe('nvim_echo', function()
    local screen

    before_each(function()
      screen = Screen.new(40, 8)
      screen:attach()
      screen:set_default_attr_ids({
        [0] = {bold = true, foreground = Screen.colors.Blue},
        [1] = {bold = true, foreground = Screen.colors.SeaGreen},
        [2] = {bold = true, reverse = true},
        [3] = {foreground = Screen.colors.Brown, bold = true}, -- Statement
        [4] = {foreground = Screen.colors.SlateBlue}, -- Special
      })
      command('highlight Statement gui=bold guifg=Brown')
      command('highlight Special guifg=SlateBlue')
    end)

    it('should clear cmdline message before echo', function()
      feed(':call nvim_echo([["msg"]], v:false, {})<CR>')
      screen:expect{grid=[[
        ^                                        |
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        msg                                     |
      ]]}
    end)

    it('can show highlighted line', function()
      nvim_async("echo", {{"msg_a"}, {"msg_b", "Statement"}, {"msg_c", "Special"}}, true, {})
      screen:expect{grid=[[
        ^                                        |
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        msg_a{3:msg_b}{4:msg_c}                         |
      ]]}
    end)

    it('can show highlighted multiline', function()
      nvim_async("echo", {{"msg_a\nmsg_a", "Statement"}, {"msg_b", "Special"}}, true, {})
      screen:expect{grid=[[
                                                |
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {2:                                        }|
        {3:msg_a}                                   |
        {3:msg_a}{4:msg_b}                              |
        {1:Press ENTER or type command to continue}^ |
      ]]}
    end)

    it('can save message history', function()
      nvim('command', 'set cmdheight=2') -- suppress Press ENTER
      nvim("echo", {{"msg\nmsg"}, {"msg"}}, true, {})
      eq("msg\nmsgmsg", exec_capture('messages'))
    end)

    it('can disable saving message history', function()
      nvim('command', 'set cmdheight=2') -- suppress Press ENTER
      nvim_async("echo", {{"msg\nmsg"}, {"msg"}}, false, {})
      eq("", exec_capture('messages'))
    end)
  end)


  describe('nvim_open_term', function()
    local screen

    before_each(function()
      screen = Screen.new(100, 35)
      screen:attach()
      screen:set_default_attr_ids({
        [0] = {bold=true, foreground=Screen.colors.Blue},
        [1] = {background = Screen.colors.Plum1};
        [2] = {background = tonumber('0xffff40'), bg_indexed = true};
        [3] = {background = Screen.colors.Plum1, fg_indexed = true, foreground = tonumber('0x00e000')};
        [4] = {bold = true, reverse = true, background = Screen.colors.Plum1};
        [5] = {foreground = Screen.colors.Blue, background = Screen.colors.LightMagenta, bold = true};
        [6] = {bold = true};
        [7] = {reverse = true, background = Screen.colors.LightMagenta};
      })
    end)

    it('can batch process sequences', function()
      local b = meths.create_buf(true,true)
      meths.open_win(b, false, {width=79, height=31, row=1, col=1, relative='editor'})
      local t = meths.open_term(b, {})

      meths.chan_send(t, io.open("test/functional/fixtures/smile2.cat", "r"):read("*a"))
      screen:expect{grid=[[
        ^                                                                                                    |
        {0:~}{1::smile                                                                         }{0:                    }|
        {0:~}{1:                            }{2:oooo$$$$$$$$$$$$oooo}{1:                               }{0:                    }|
        {0:~}{1:                        }{2:oo$$$$$$$$$$$$$$$$$$$$$$$$o}{1:                            }{0:                    }|
        {0:~}{1:                     }{2:oo$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$o}{1:         }{2:o$}{1:   }{2:$$}{1: }{2:o$}{1:      }{0:                    }|
        {0:~}{1:     }{2:o}{1: }{2:$}{1: }{2:oo}{1:        }{2:o$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$o}{1:       }{2:$$}{1: }{2:$$}{1: }{2:$$o$}{1:     }{0:                    }|
        {0:~}{1:  }{2:oo}{1: }{2:$}{1: }{2:$}{1: "}{2:$}{1:      }{2:o$$$$$$$$$}{1:    }{2:$$$$$$$$$$$$$}{1:    }{2:$$$$$$$$$o}{1:       }{2:$$$o$$o$}{1:      }{0:                    }|
        {0:~}{1:  "}{2:$$$$$$o$}{1:     }{2:o$$$$$$$$$}{1:      }{2:$$$$$$$$$$$}{1:      }{2:$$$$$$$$$$o}{1:    }{2:$$$$$$$$}{1:       }{0:                    }|
        {0:~}{1:    }{2:$$$$$$$}{1:    }{2:$$$$$$$$$$$}{1:      }{2:$$$$$$$$$$$}{1:      }{2:$$$$$$$$$$$$$$$$$$$$$$$}{1:       }{0:                    }|
        {0:~}{1:    }{2:$$$$$$$$$$$$$$$$$$$$$$$}{1:    }{2:$$$$$$$$$$$$$}{1:    }{2:$$$$$$$$$$$$$$}{1:  """}{2:$$$}{1:         }{0:                    }|
        {0:~}{1:     "}{2:$$$}{1:""""}{2:$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$}{1:     "}{2:$$$}{1:        }{0:                    }|
        {0:~}{1:      }{2:$$$}{1:   }{2:o$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$}{1:     "}{2:$$$o}{1:      }{0:                    }|
        {0:~}{1:     }{2:o$$}{1:"   }{2:$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$}{1:       }{2:$$$o}{1:     }{0:                    }|
        {0:~}{1:     }{2:$$$}{1:    }{2:$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$}{1:" "}{2:$$$$$$ooooo$$$$o}{1:   }{0:                    }|
        {0:~}{1:    }{2:o$$$oooo$$$$$}{1:  }{2:$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$}{1:   }{2:o$$$$$$$$$$$$$$$$$}{1:  }{0:                    }|
        {0:~}{1:    }{2:$$$$$$$$}{1:"}{2:$$$$}{1:   }{2:$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$}{1:     }{2:$$$$}{1:""""""""        }{0:                    }|
        {0:~}{1:   """"       }{2:$$$$}{1:    "}{2:$$$$$$$$$$$$$$$$$$$$$$$$$$$$}{1:"      }{2:o$$$}{1:                 }{0:                    }|
        {0:~}{1:              "}{2:$$$o}{1:     """}{2:$$$$$$$$$$$$$$$$$$}{1:"}{2:$$}{1:"         }{2:$$$}{1:                  }{0:                    }|
        {0:~}{1:                }{2:$$$o}{1:          "}{2:$$}{1:""}{2:$$$$$$}{1:""""           }{2:o$$$}{1:                   }{0:                    }|
        {0:~}{1:                 }{2:$$$$o}{1:                                }{2:o$$$}{1:"                    }{0:                    }|
        {0:~}{1:                  "}{2:$$$$o}{1:      }{2:o$$$$$$o}{1:"}{2:$$$$o}{1:        }{2:o$$$$}{1:                      }{0:                    }|
        {0:~}{1:                    "}{2:$$$$$oo}{1:     ""}{2:$$$$o$$$$$o}{1:   }{2:o$$$$}{1:""                       }{0:                    }|
        {0:~}{1:                       ""}{2:$$$$$oooo}{1:  "}{2:$$$o$$$$$$$$$}{1:"""                          }{0:                    }|
        {0:~}{1:                          ""}{2:$$$$$$$oo}{1: }{2:$$$$$$$$$$}{1:                               }{0:                    }|
        {0:~}{1:                                  """"}{2:$$$$$$$$$$$}{1:                              }{0:                    }|
        {0:~}{1:                                      }{2:$$$$$$$$$$$$}{1:                             }{0:                    }|
        {0:~}{1:                                       }{2:$$$$$$$$$$}{1:"                             }{0:                    }|
        {0:~}{1:                                        "}{2:$$$}{1:""""                               }{0:                    }|
        {0:~}{1:                                                                               }{0:                    }|
        {0:~}{3:Press ENTER or type command to continue}{1:                                        }{0:                    }|
        {0:~}{4:term://~/config2/docs/pres//32693:vim --clean +smile         29,39          All}{0:                    }|
        {0:~}{1::call nvim__screenshot("smile2.cat")                                           }{0:                    }|
        {0:~                                                                                                   }|
        {0:~                                                                                                   }|
                                                                                                            |
      ]]}
    end)

    it('can handle input', function()
      screen:try_resize(50, 10)
      eq({3, 2}, exec_lua [[
        buf = vim.api.nvim_create_buf(1,1)

        stream = ''
        do_the_echo = false
        function input(_,t1,b1,data)
          stream = stream .. data
          _G.vals = {t1, b1}
          if do_the_echo then
            vim.api.nvim_chan_send(t1, data)
          end
        end

        term = vim.api.nvim_open_term(buf, {on_input=input})
        vim.api.nvim_open_win(buf, true, {width=40, height=5, row=1, col=1, relative='editor'})
        return {term, buf}
      ]])

      screen:expect{grid=[[
                                                          |
        {0:~}{1:^                                        }{0:         }|
        {0:~}{1:                                        }{0:         }|
        {0:~}{1:                                        }{0:         }|
        {0:~}{1:                                        }{0:         }|
        {0:~}{1:                                        }{0:         }|
        {0:~                                                 }|
        {0:~                                                 }|
        {0:~                                                 }|
                                                          |
      ]]}

      feed 'iba<c-x>bla'
      screen:expect{grid=[[
                                                          |
        {0:~}{7: }{1:                                       }{0:         }|
        {0:~}{1:                                        }{0:         }|
        {0:~}{1:                                        }{0:         }|
        {0:~}{1:                                        }{0:         }|
        {0:~}{1:                                        }{0:         }|
        {0:~                                                 }|
        {0:~                                                 }|
        {0:~                                                 }|
        {6:-- TERMINAL --}                                    |
      ]]}

      eq('ba\024bla', exec_lua [[ return stream ]])
      eq({3,2}, exec_lua [[ return vals ]])

      exec_lua [[ do_the_echo = true ]]
      feed 'herrejösses!'

      screen:expect{grid=[[
                                                          |
        {0:~}{1:herrejösses!}{7: }{1:                           }{0:         }|
        {0:~}{1:                                        }{0:         }|
        {0:~}{1:                                        }{0:         }|
        {0:~}{1:                                        }{0:         }|
        {0:~}{1:                                        }{0:         }|
        {0:~                                                 }|
        {0:~                                                 }|
        {0:~                                                 }|
        {6:-- TERMINAL --}                                    |
      ]]}
      eq('ba\024blaherrejösses!', exec_lua [[ return stream ]])
    end)
  end)

  describe('nvim_del_mark', function()
    it('works', function()
      local buf = meths.create_buf(false,true)
      meths.buf_set_lines(buf, -1, -1, true, {'a', 'bit of', 'text'})
      eq(true, meths.buf_set_mark(buf, 'F', 2, 2, {}))
      eq(true, meths.del_mark('F'))
      eq({0, 0}, meths.buf_get_mark(buf, 'F'))
    end)
    it('validation', function()
      eq("Invalid mark name (must be file/uppercase): 'f'", pcall_err(meths.del_mark, 'f'))
      eq("Invalid mark name (must be file/uppercase): '!'", pcall_err(meths.del_mark, '!'))
      eq("Invalid mark name (must be a single char): 'fail'", pcall_err(meths.del_mark, 'fail'))
    end)
  end)
  describe('nvim_get_mark', function()
    it('works', function()
      local buf = meths.create_buf(false,true)
      meths.buf_set_lines(buf, -1, -1, true, {'a', 'bit of', 'text'})
      meths.buf_set_mark(buf, 'F', 2, 2, {})
      meths.buf_set_name(buf, "mybuf")
      local mark = meths.get_mark('F', {})
      -- Compare the path tail only
      assert(string.find(mark[4], "mybuf$"))
      eq({2, 2, buf.id, mark[4]}, mark)
    end)
    it('validation', function()
      eq("Invalid mark name (must be file/uppercase): 'f'", pcall_err(meths.get_mark, 'f', {}))
      eq("Invalid mark name (must be file/uppercase): '!'", pcall_err(meths.get_mark, '!', {}))
      eq("Invalid mark name (must be a single char): 'fail'", pcall_err(meths.get_mark, 'fail', {}))
    end)
    it('returns the expected when mark is not set', function()
      eq(true, meths.del_mark('A'))
      eq({0, 0, 0, ''}, meths.get_mark('A', {}))
    end)
    it('works with deleted buffers', function()
      local fname = tmpname()
      write_file(fname, 'a\nbit of\text')
      nvim("command", "edit " .. fname)
      local buf = meths.get_current_buf()

      meths.buf_set_mark(buf, 'F', 2, 2, {})
      nvim("command", "new") -- Create new buf to avoid :bd failing
      nvim("command", "bd! " .. buf.id)
      os.remove(fname)

      local mark = meths.get_mark('F', {})
      -- To avoid comparing relative vs absolute path
      local mfname = mark[4]
      local tail_patt = [[[\/][^\/]*$]]
      -- tail of paths should be equals
      eq(fname:match(tail_patt), mfname:match(tail_patt))
      eq({2, 2, buf.id, mark[4]}, mark)
    end)
  end)
  describe('nvim_eval_statusline', function()
    it('works', function()
      eq({
          str = '%StatusLineStringWithHighlights',
          width = 31
        },
        meths.eval_statusline(
          '%%StatusLineString%#WarningMsg#WithHighlights',
          {}))
    end)
    it('doesn\'t exceed maxwidth', function()
      eq({
          str = 'Should be trun>',
          width = 15
        },
        meths.eval_statusline(
          'Should be truncated%<',
          { maxwidth = 15 }))
    end)
    it('supports ASCII fillchar', function()
      eq({ str = 'a~~~b', width = 5 },
         meths.eval_statusline('a%=b', { fillchar = '~', maxwidth = 5 }))
    end)
    it('supports single-width multibyte fillchar', function()
      eq({ str = 'a━━━b', width = 5 },
         meths.eval_statusline('a%=b', { fillchar = '━', maxwidth = 5 }))
    end)
    it('treats double-width fillchar as single-width', function()
      eq({ str = 'a哦哦哦b', width = 5 },
         meths.eval_statusline('a%=b', { fillchar = '哦', maxwidth = 5 }))
    end)
    it('treats control character fillchar as single-width', function()
      eq({ str = 'a\031\031\031b', width = 5 },
         meths.eval_statusline('a%=b', { fillchar = '\031', maxwidth = 5 }))
    end)
    it('rejects multiple-character fillchar', function()
      eq("Invalid 'fillchar': expected single character",
         pcall_err(meths.eval_statusline, '', { fillchar = 'aa' }))
    end)
    it('rejects empty string fillchar', function()
      eq("Invalid 'fillchar': expected single character",
         pcall_err(meths.eval_statusline, '', { fillchar = '' }))
    end)
    it('rejects non-string fillchar', function()
      eq("Invalid 'fillchar': expected String, got Integer",
         pcall_err(meths.eval_statusline, '', { fillchar = 1 }))
    end)
    it('rejects invalid string', function()
      eq('E539: Illegal character <}>',
         pcall_err(meths.eval_statusline, '%{%}', {}))
    end)
    it('supports various items', function()
      eq({ str = '0', width = 1 },
         meths.eval_statusline('%l', { maxwidth = 5 }))
      command('set readonly')
      eq({ str = '[RO]', width = 4 },
         meths.eval_statusline('%r', { maxwidth = 5 }))
      local screen = Screen.new(80, 24)
      screen:attach()
      command('set showcmd')
      feed('1234')
      screen:expect({any = '1234'})
      eq({ str = '1234', width = 4 },
         meths.eval_statusline('%S', { maxwidth = 5 }))
      feed('56')
      screen:expect({any = '123456'})
      eq({ str = '<3456', width = 5 },
         meths.eval_statusline('%S', { maxwidth = 5 }))
    end)
    describe('highlight parsing', function()
      it('works', function()
        eq({
            str = "TextWithWarningHighlightTextWithUserHighlight",
            width = 45,
            highlights = {
              { start = 0, group = 'WarningMsg' },
              { start = 24, group = 'User1' }
            },
          },
          meths.eval_statusline(
            '%#WarningMsg#TextWithWarningHighlight%1*TextWithUserHighlight',
            { highlights = true }))
      end)
      it('works with no highlight', function()
        eq({
            str = "TextWithNoHighlight",
            width = 19,
            highlights = {
              { start = 0, group = 'StatusLine' },
            },
          },
          meths.eval_statusline(
            'TextWithNoHighlight',
            { highlights = true }))
      end)
      it('works with inactive statusline', function()
        command('split')

        eq({
            str = 'TextWithNoHighlightTextWithWarningHighlight',
            width = 43,
            highlights = {
              { start = 0, group = 'StatusLineNC' },
              { start = 19, group = 'WarningMsg' }
            }
          },
          meths.eval_statusline(
            'TextWithNoHighlight%#WarningMsg#TextWithWarningHighlight',
            { winid = meths.list_wins()[2].id, highlights = true }))
      end)
      it('works with tabline', function()
        eq({
            str = 'TextWithNoHighlightTextWithWarningHighlight',
            width = 43,
            highlights = {
              { start = 0, group = 'TabLineFill' },
              { start = 19, group = 'WarningMsg' }
            }
          },
          meths.eval_statusline(
            'TextWithNoHighlight%#WarningMsg#TextWithWarningHighlight',
            { use_tabline = true, highlights = true }))
      end)
      it('works with winbar', function()
        eq({
            str = 'TextWithNoHighlightTextWithWarningHighlight',
            width = 43,
            highlights = {
              { start = 0, group = 'WinBar' },
              { start = 19, group = 'WarningMsg' }
            }
          },
          meths.eval_statusline(
            'TextWithNoHighlight%#WarningMsg#TextWithWarningHighlight',
            { use_winbar = true, highlights = true }))
      end)
      it('works with statuscolumn', function()
        exec([[
          let &stc='%C%s%=%l '
          set cul nu nuw=3 scl=yes:2 fdc=2
          call setline(1, repeat(['aaaaa'], 5))
          let g:ns = nvim_create_namespace('')
          call sign_define('a', {'text':'aa', 'texthl':'IncSearch', 'numhl':'Normal'})
          call sign_place(2, 1, 'a', bufnr(), {'lnum':4})
          call nvim_buf_set_extmark(0, g:ns, 3, 1, { 'sign_text':'bb', 'sign_hl_group':'ErrorMsg' })
          1,5fold | 1,5 fold | foldopen!
          norm 4G
        ]])
        eq({
          str = '││aabb 4 ',
          width = 9,
          highlights = {
            { group = 'CursorLineFold', start = 0 },
            { group = 'Normal', start = 6 },
            { group = 'IncSearch', start = 6 },
            { group = 'ErrorMsg', start = 8 },
            { group = 'Normal', start = 10 }
          }
        }, meths.eval_statusline('%C%s%=%l ', { use_statuscol_lnum = 4, highlights = true }))
        eq({
          str = '3 ' ,
          width = 2,
          highlights = {
            { group = 'LineNr', start = 0 },
            { group = 'ErrorMsg', start = 1 }
          }
        }, meths.eval_statusline('%l%#ErrorMsg# ', { use_statuscol_lnum = 3, highlights = true }))
      end)
      it('no memory leak with click functions', function()
        meths.eval_statusline('%@ClickFunc@StatusLineStringWithClickFunc%T', {})
        eq({
            str = 'StatusLineStringWithClickFunc',
            width = 29
          },
          meths.eval_statusline(
            '%@ClickFunc@StatusLineStringWithClickFunc%T',
            {})
          )
      end)
    end)
  end)

  describe('nvim_parse_cmd', function()
    it('works', function()
      eq({
        cmd = 'echo',
        args = { 'foo' },
        bang = false,
        addr = 'none',
        magic = {
            file = false,
            bar = false
        },
        nargs = '*',
        nextcmd = '',
        mods = {
          browse = false,
          confirm = false,
          emsg_silent = false,
          filter = {
              pattern = "",
              force = false
          },
          hide = false,
          horizontal = false,
          keepalt = false,
          keepjumps = false,
          keepmarks = false,
          keeppatterns = false,
          lockmarks = false,
          noautocmd = false,
          noswapfile = false,
          sandbox = false,
          silent = false,
          split = "",
          tab = -1,
          unsilent = false,
          verbose = -1,
          vertical = false,
        }
      }, meths.parse_cmd('echo foo', {}))
    end)
    it('works with ranges', function()
      eq({
        cmd = 'substitute',
        args = { '/math.random/math.max/' },
        bang = false,
        range = { 4, 6 },
        addr = 'line',
        magic = {
            file = false,
            bar = false
        },
        nargs = '*',
        nextcmd = '',
        mods = {
          browse = false,
          confirm = false,
          emsg_silent = false,
          filter = {
              pattern = "",
              force = false
          },
          hide = false,
          horizontal = false,
          keepalt = false,
          keepjumps = false,
          keepmarks = false,
          keeppatterns = false,
          lockmarks = false,
          noautocmd = false,
          noswapfile = false,
          sandbox = false,
          silent = false,
          split = "",
          tab = -1,
          unsilent = false,
          verbose = -1,
          vertical = false,
        }
      }, meths.parse_cmd('4,6s/math.random/math.max/', {}))
    end)
    it('works with count', function()
      eq({
        cmd = 'buffer',
        args = {},
        bang = false,
        range = { 1 },
        count = 1,
        addr = 'buf',
        magic = {
            file = false,
            bar = true
        },
        nargs = '*',
        nextcmd = '',
        mods = {
          browse = false,
          confirm = false,
          emsg_silent = false,
          filter = {
              pattern = "",
              force = false
          },
          hide = false,
          horizontal = false,
          keepalt = false,
          keepjumps = false,
          keepmarks = false,
          keeppatterns = false,
          lockmarks = false,
          noautocmd = false,
          noswapfile = false,
          sandbox = false,
          silent = false,
          split = "",
          tab = -1,
          unsilent = false,
          verbose = -1,
          vertical = false,
        }
      }, meths.parse_cmd('buffer 1', {}))
    end)
    it('works with register', function()
      eq({
        cmd = 'put',
        args = {},
        bang = false,
        range = {},
        reg = '+',
        addr = 'line',
        magic = {
            file = false,
            bar = true
        },
        nargs = '0',
        nextcmd = '',
        mods = {
          browse = false,
          confirm = false,
          emsg_silent = false,
          filter = {
              pattern = "",
              force = false
          },
          hide = false,
          horizontal = false,
          keepalt = false,
          keepjumps = false,
          keepmarks = false,
          keeppatterns = false,
          lockmarks = false,
          noautocmd = false,
          noswapfile = false,
          sandbox = false,
          silent = false,
          split = "",
          tab = -1,
          unsilent = false,
          verbose = -1,
          vertical = false,
        }
      }, meths.parse_cmd('put +', {}))
      eq({
        cmd = 'put',
        args = {},
        bang = false,
        range = {},
        reg = '',
        addr = 'line',
        magic = {
            file = false,
            bar = true
        },
        nargs = '0',
        nextcmd = '',
        mods = {
          browse = false,
          confirm = false,
          emsg_silent = false,
          filter = {
              pattern = "",
              force = false
          },
          hide = false,
          horizontal = false,
          keepalt = false,
          keepjumps = false,
          keepmarks = false,
          keeppatterns = false,
          lockmarks = false,
          noautocmd = false,
          noswapfile = false,
          sandbox = false,
          silent = false,
          split = "",
          tab = -1,
          unsilent = false,
          verbose = -1,
          vertical = false,
        }
      }, meths.parse_cmd('put', {}))
    end)
    it('works with range, count and register', function()
      eq({
        cmd = 'delete',
        args = {},
        bang = false,
        range = { 3, 7 },
        count = 7,
        reg = '*',
        addr = 'line',
        magic = {
            file = false,
            bar = true
        },
        nargs = '0',
        nextcmd = '',
        mods = {
          browse = false,
          confirm = false,
          emsg_silent = false,
          filter = {
              pattern = "",
              force = false
          },
          hide = false,
          horizontal = false,
          keepalt = false,
          keepjumps = false,
          keepmarks = false,
          keeppatterns = false,
          lockmarks = false,
          noautocmd = false,
          noswapfile = false,
          sandbox = false,
          silent = false,
          split = "",
          tab = -1,
          unsilent = false,
          verbose = -1,
          vertical = false,
        }
      }, meths.parse_cmd('1,3delete * 5', {}))
    end)
    it('works with bang', function()
      eq({
        cmd = 'write',
        args = {},
        bang = true,
        range = {},
        addr = 'line',
        magic = {
            file = true,
            bar = true
        },
        nargs = '?',
        nextcmd = '',
        mods = {
          browse = false,
          confirm = false,
          emsg_silent = false,
          filter = {
              pattern = "",
              force = false
          },
          hide = false,
          horizontal = false,
          keepalt = false,
          keepjumps = false,
          keepmarks = false,
          keeppatterns = false,
          lockmarks = false,
          noautocmd = false,
          noswapfile = false,
          sandbox = false,
          silent = false,
          split = "",
          tab = -1,
          unsilent = false,
          verbose = -1,
          vertical = false,
        },
      }, meths.parse_cmd('w!', {}))
    end)
    it('works with modifiers', function()
      eq({
        cmd = 'split',
        args = { 'foo.txt' },
        bang = false,
        range = {},
        addr = '?',
        magic = {
            file = true,
            bar = true
        },
        nargs = '?',
        nextcmd = '',
        mods = {
          browse = false,
          confirm = false,
          emsg_silent = true,
          filter = {
              pattern = "foo",
              force = false
          },
          hide = false,
          horizontal = true,
          keepalt = false,
          keepjumps = false,
          keepmarks = false,
          keeppatterns = false,
          lockmarks = false,
          noautocmd = false,
          noswapfile = false,
          sandbox = false,
          silent = true,
          split = "topleft",
          tab = 1,
          unsilent = false,
          verbose = 15,
          vertical = false,
        },
      }, meths.parse_cmd('15verbose silent! horizontal topleft tab filter /foo/ split foo.txt', {}))
      eq({
        cmd = 'split',
        args = { 'foo.txt' },
        bang = false,
        range = {},
        addr = '?',
        magic = {
            file = true,
            bar = true
        },
        nargs = '?',
        nextcmd = '',
        mods = {
          browse = false,
          confirm = true,
          emsg_silent = false,
          filter = {
              pattern = "foo",
              force = true
          },
          hide = false,
          horizontal = false,
          keepalt = false,
          keepjumps = false,
          keepmarks = false,
          keeppatterns = false,
          lockmarks = false,
          noautocmd = false,
          noswapfile = false,
          sandbox = false,
          silent = false,
          split = "botright",
          tab = 0,
          unsilent = true,
          verbose = 0,
          vertical = false,
        },
      }, meths.parse_cmd('0verbose unsilent botright 0tab confirm filter! /foo/ split foo.txt', {}))
    end)
    it('works with user commands', function()
      command('command -bang -nargs=+ -range -addr=lines MyCommand echo foo')
      eq({
        cmd = 'MyCommand',
        args = { 'test', 'it' },
        bang = true,
        range = { 4, 6 },
        addr = 'line',
        magic = {
            file = false,
            bar = false
        },
        nargs = '+',
        nextcmd = '',
        mods = {
          browse = false,
          confirm = false,
          emsg_silent = false,
          filter = {
              pattern = "",
              force = false
          },
          hide = false,
          horizontal = false,
          keepalt = false,
          keepjumps = false,
          keepmarks = false,
          keeppatterns = false,
          lockmarks = false,
          noautocmd = false,
          noswapfile = false,
          sandbox = false,
          silent = false,
          split = "",
          tab = -1,
          unsilent = false,
          verbose = -1,
          vertical = false,
        }
      }, meths.parse_cmd('4,6MyCommand! test it', {}))
    end)
    it('works for commands separated by bar', function()
      eq({
        cmd = 'argadd',
        args = { 'a.txt' },
        bang = false,
        range = {},
        addr = 'arg',
        magic = {
            file = true,
            bar = true
        },
        nargs = '*',
        nextcmd = 'argadd b.txt',
        mods = {
          browse = false,
          confirm = false,
          emsg_silent = false,
          filter = {
              pattern = "",
              force = false
          },
          hide = false,
          horizontal = false,
          keepalt = false,
          keepjumps = false,
          keepmarks = false,
          keeppatterns = false,
          lockmarks = false,
          noautocmd = false,
          noswapfile = false,
          sandbox = false,
          silent = false,
          split = "",
          tab = -1,
          unsilent = false,
          verbose = -1,
          vertical = false,
        }
      }, meths.parse_cmd('argadd a.txt | argadd b.txt', {}))
    end)
    it('works for nargs=1', function()
      command('command -nargs=1 MyCommand echo <q-args>')
      eq({
        cmd = 'MyCommand',
        args = { 'test it' },
        bang = false,
        addr = 'none',
        magic = {
            file = false,
            bar = false
        },
        nargs = '1',
        nextcmd = '',
        mods = {
          browse = false,
          confirm = false,
          emsg_silent = false,
          filter = {
              pattern = "",
              force = false
          },
          hide = false,
          horizontal = false,
          keepalt = false,
          keepjumps = false,
          keepmarks = false,
          keeppatterns = false,
          lockmarks = false,
          noautocmd = false,
          noswapfile = false,
          sandbox = false,
          silent = false,
          split = "",
          tab = -1,
          unsilent = false,
          verbose = -1,
          vertical = false,
        }
      }, meths.parse_cmd('MyCommand test it', {}))
    end)
    it('validates command', function()
      eq('Error while parsing command line', pcall_err(meths.parse_cmd, '', {}))
      eq('Error while parsing command line', pcall_err(meths.parse_cmd, '" foo', {}))
      eq('Error while parsing command line: E492: Not an editor command: Fubar',
         pcall_err(meths.parse_cmd, 'Fubar', {}))
      command('command! Fubar echo foo')
      eq('Error while parsing command line: E477: No ! allowed',
         pcall_err(meths.parse_cmd, 'Fubar!', {}))
      eq('Error while parsing command line: E481: No range allowed',
         pcall_err(meths.parse_cmd, '4,6Fubar', {}))
      command('command! Foobar echo foo')
      eq('Error while parsing command line: E464: Ambiguous use of user-defined command',
         pcall_err(meths.parse_cmd, 'F', {}))
    end)
    it('does not interfere with printing line in Ex mode #19400', function()
      local screen = Screen.new(60, 7)
      screen:set_default_attr_ids({
        [0] = {bold = true, foreground = Screen.colors.Blue},  -- NonText
        [1] = {bold = true, reverse = true},  -- MsgSeparator
      })
      screen:attach()
      insert([[
        foo
        bar]])
      feed('gQ1')
      screen:expect([[
        foo                                                         |
        bar                                                         |
        {0:~                                                           }|
        {0:~                                                           }|
        {1:                                                            }|
        Entering Ex mode.  Type "visual" to go to Normal mode.      |
        :1^                                                          |
      ]])
      eq('Error while parsing command line', pcall_err(meths.parse_cmd, '', {}))
      feed('<CR>')
      screen:expect([[
        foo                                                         |
        bar                                                         |
        {1:                                                            }|
        Entering Ex mode.  Type "visual" to go to Normal mode.      |
        :1                                                          |
        foo                                                         |
        :^                                                           |
      ]])
    end)
    it('does not move cursor or change search history/pattern #19878 #19890', function()
      meths.buf_set_lines(0, 0, -1, true, {'foo', 'bar', 'foo', 'bar'})
      eq({1, 0}, meths.win_get_cursor(0))
      eq('', funcs.getreg('/'))
      eq('', funcs.histget('search'))
      feed(':')  -- call the API in cmdline mode to test whether it changes search history
      eq({
        cmd = 'normal',
        args = {'x'},
        bang = true,
        range = {3, 4},
        addr = 'line',
        magic = {
          file = false,
          bar = false,
        },
        nargs = '+',
        nextcmd = '',
        mods = {
          browse = false,
          confirm = false,
          emsg_silent = false,
          filter = {
            pattern = "",
            force = false,
          },
          hide = false,
          horizontal = false,
          keepalt = false,
          keepjumps = false,
          keepmarks = false,
          keeppatterns = false,
          lockmarks = false,
          noautocmd = false,
          noswapfile = false,
          sandbox = false,
          silent = false,
          split = "",
          tab = -1,
          unsilent = false,
          verbose = -1,
          vertical = false,
        }
      }, meths.parse_cmd('+2;/bar/normal! x', {}))
      eq({1, 0}, meths.win_get_cursor(0))
      eq('', funcs.getreg('/'))
      eq('', funcs.histget('search'))
    end)
    it('result can be used directly by nvim_cmd #20051', function()
      eq("foo", meths.cmd(meths.parse_cmd('echo "foo"', {}), { output = true }))
      meths.cmd(meths.parse_cmd("set cursorline", {}), {})
      eq(true, meths.get_option_value("cursorline", {}))
    end)
    it('no side-effects (error messages) in pcall() #20339', function()
      eq({ false, 'Error while parsing command line: E16: Invalid range' },
        exec_lua([=[return {pcall(vim.api.nvim_parse_cmd, "'<,'>n", {})}]=]))
      eq('', eval('v:errmsg'))
    end)
  end)

  describe('nvim_cmd', function()
    it('works', function ()
      meths.cmd({ cmd = "set", args = { "cursorline" } }, {})
      eq(true, meths.get_option_value("cursorline", {}))
    end)

    it('validation', function()
      eq("Invalid 'cmd': expected non-empty String",
        pcall_err(meths.cmd, { cmd = ""}, {}))
      eq("Invalid 'cmd': expected non-empty String",
        pcall_err(meths.cmd, { cmd = {}}, {}))
      eq("Invalid 'args': expected Array, got Boolean",
        pcall_err(meths.cmd, { cmd = "set", args = true }, {}))
      eq("Invalid 'magic': expected Dict, got Array",
        pcall_err(meths.cmd, { cmd = "set", args = {}, magic = {} }, {}))
      eq("Invalid command arg: expected non-whitespace",
        pcall_err(meths.cmd, { cmd = "set", args = {'  '}, }, {}))
      eq("Invalid command arg: expected valid type, got Array",
        pcall_err(meths.cmd, { cmd = "set", args = {{}}, }, {}))
      eq("Wrong number of arguments",
        pcall_err(meths.cmd, { cmd = "aboveleft", args = {}, }, {}))
      eq("Command cannot accept bang: print",
        pcall_err(meths.cmd, { cmd = "print", args = {}, bang = true }, {}))

      eq("Command cannot accept range: set",
        pcall_err(meths.cmd, { cmd = "set", args = {}, range = {1} }, {}))
      eq("Invalid 'range': expected Array, got Boolean",
        pcall_err(meths.cmd, { cmd = "print", args = {}, range = true }, {}))
      eq("Invalid 'range': expected <=2 elements",
        pcall_err(meths.cmd, { cmd = "print", args = {}, range = {1,2,3,4} }, {}))
      eq("Invalid range element: expected non-negative Integer",
        pcall_err(meths.cmd, { cmd = "print", args = {}, range = {-1} }, {}))

      eq("Command cannot accept count: set",
        pcall_err(meths.cmd, { cmd = "set", args = {}, count = 1 }, {}))
      eq("Invalid 'count': expected non-negative Integer",
        pcall_err(meths.cmd, { cmd = "print", args = {}, count = true }, {}))
      eq("Invalid 'count': expected non-negative Integer",
        pcall_err(meths.cmd, { cmd = "print", args = {}, count = -1 }, {}))

      eq("Command cannot accept register: set",
        pcall_err(meths.cmd, { cmd = "set", args = {}, reg = 'x' }, {}))
      eq('Cannot use register "=',
        pcall_err(meths.cmd, { cmd = "put", args = {}, reg = '=' }, {}))
      eq("Invalid 'reg': expected single character, got xx",
        pcall_err(meths.cmd, { cmd = "put", args = {}, reg = 'xx' }, {}))

      -- #20681
      eq('Invalid command: "win_getid"', pcall_err(meths.cmd, { cmd = 'win_getid'}, {}))
      eq('Invalid command: "echo "hi""', pcall_err(meths.cmd, { cmd = 'echo "hi"'}, {}))
      eq('Invalid command: "win_getid"', pcall_err(exec_lua, [[return vim.cmd.win_getid{}]]))

      -- Lua call allows empty {} for dict item.
      eq('', exec_lua([[return vim.cmd{ cmd = "set", args = {}, magic = {} }]]))
      eq('', exec_lua([[return vim.cmd{ cmd = "set", args = {}, mods = {} }]]))

      -- Lua call does not allow non-empty list-like {} for dict item.
      eq("Invalid 'magic': expected Dict, got Array",
        pcall_err(exec_lua, [[return vim.cmd{ cmd = "set", args = {}, magic = { 'a' } }]]))
      eq("Invalid key: 'bogus'",
        pcall_err(exec_lua, [[return vim.cmd{ cmd = "set", args = {}, magic = { bogus = true } }]]))
      eq("Invalid key: 'bogus'",
        pcall_err(exec_lua, [[return vim.cmd{ cmd = "set", args = {}, mods = { bogus = true } }]]))
    end)

    it('captures output', function()
      eq("foo", meths.cmd({ cmd = "echo", args = { '"foo"' } }, { output = true }))
    end)

    it('sets correct script context', function()
      meths.cmd({ cmd = "set", args = { "cursorline" } }, {})
      local str = exec_capture([[verbose set cursorline?]])
      neq(nil, str:find("cursorline\n\tLast set from API client %(channel id %d+%)"))
    end)

    it('works with range', function()
      insert [[
        line1
        line2
        line3
        line4
        you didn't expect this
        line5
        line6
      ]]
      meths.cmd({ cmd = "del", range = {2, 4} }, {})
      expect [[
        line1
        you didn't expect this
        line5
        line6
      ]]
    end)
    it('works with count', function()
      insert [[
        line1
        line2
        line3
        line4
        you didn't expect this
        line5
        line6
      ]]
      meths.cmd({ cmd = "del", range = { 2 }, count = 4 }, {})
      expect [[
        line1
        line5
        line6
      ]]
    end)
    it('works with register', function()
      insert [[
        line1
        line2
        line3
        line4
        you didn't expect this
        line5
        line6
      ]]
      meths.cmd({ cmd = "del", range = { 2, 4 }, reg = 'a' }, {})
      command('1put a')
      expect [[
        line1
        line2
        line3
        line4
        you didn't expect this
        line5
        line6
      ]]
    end)
    it('works with bang', function ()
      meths.create_user_command("Foo", 'echo "<bang>"', { bang = true })
      eq("!", meths.cmd({ cmd = "Foo", bang = true }, { output = true }))
      eq("", meths.cmd({ cmd = "Foo", bang = false }, { output = true }))
    end)
    it('works with modifiers', function()
      -- with silent = true output is still captured
      eq('1',
         meths.cmd({ cmd = 'echomsg', args = { '1' }, mods = { silent = true } },
                   { output = true }))
      -- but message isn't added to message history
      eq('', meths.cmd({ cmd = 'messages' }, { output = true }))

      meths.create_user_command("Foo", 'set verbose', {})
      eq("  verbose=1", meths.cmd({ cmd = "Foo", mods = { verbose = 1 } }, { output = true }))

      meths.create_user_command("Mods", "echo '<mods>'", {})
      eq('keepmarks keeppatterns silent 3verbose aboveleft horizontal',
         meths.cmd({ cmd = "Mods", mods = {
           horizontal = true,
           keepmarks = true,
           keeppatterns = true,
           silent = true,
           split = 'aboveleft',
           verbose = 3,
         } }, { output = true }))
      eq(0, meths.get_option_value("verbose", {}))

      command('edit foo.txt | edit bar.txt')
      eq('  1 #h   "foo.txt"                      line 1',
         meths.cmd({ cmd = "buffers", mods = { filter = { pattern = "foo", force = false } } },
                   { output = true }))
      eq('  2 %a   "bar.txt"                      line 1',
         meths.cmd({ cmd = "buffers", mods = { filter = { pattern = "foo", force = true } } },
                   { output = true }))

      -- with emsg_silent = true error is suppressed
      feed([[:lua vim.api.nvim_cmd({ cmd = 'call', mods = { emsg_silent = true } }, {})<CR>]])
      eq('', meths.cmd({ cmd = 'messages' }, { output = true }))
      -- error from the next command typed is not suppressed #21420
      feed(':call<CR><CR>')
      eq('E471: Argument required', meths.cmd({ cmd = 'messages' }, { output = true }))
    end)
    it('works with magic.file', function()
      exec_lua([[
        vim.api.nvim_create_user_command("Foo", function(opts)
          vim.api.nvim_echo({{ opts.fargs[1] }}, false, {})
        end, { nargs = 1 })
      ]])
      eq(luv.cwd(),
         meths.cmd({ cmd = "Foo", args = { '%:p:h' }, magic = { file = true } },
                   { output = true }))
    end)
    it('splits arguments correctly', function()
      exec([[
        function! FooFunc(...)
          echo a:000
        endfunction
      ]])
      meths.create_user_command("Foo", "call FooFunc(<f-args>)", { nargs = '+' })
      eq([=[['a quick', 'brown fox', 'jumps over the', 'lazy dog']]=],
         meths.cmd({ cmd = "Foo", args = { "a quick", "brown fox", "jumps over the", "lazy dog"}},
                   { output = true }))
      eq([=[['test \ \\ \"""\', 'more\ tests\"  ']]=],
         meths.cmd({ cmd = "Foo", args = { [[test \ \\ \"""\]], [[more\ tests\"  ]] } },
                   { output = true }))
    end)
    it('splits arguments correctly for Lua callback', function()
      meths.exec_lua([[
        local function FooFunc(opts)
          vim.print(opts.fargs)
        end

        vim.api.nvim_create_user_command("Foo", FooFunc, { nargs = '+' })
      ]], {})
      eq([[{ "a quick", "brown fox", "jumps over the", "lazy dog" }]],
         meths.cmd({ cmd = "Foo", args = { "a quick", "brown fox", "jumps over the", "lazy dog"}},
                   { output = true }))
      eq([[{ 'test \\ \\\\ \\"""\\', 'more\\ tests\\"  ' }]],
         meths.cmd({ cmd = "Foo", args = { [[test \ \\ \"""\]], [[more\ tests\"  ]] } },
                   { output = true }))
    end)
    it('works with buffer names', function()
      command("edit foo.txt | edit bar.txt")
      meths.cmd({ cmd = "buffer", args = { "foo.txt" } }, {})
      eq("foo.txt", funcs.fnamemodify(meths.buf_get_name(0), ":t"))
      meths.cmd({ cmd = "buffer", args = { "bar.txt" } }, {})
      eq("bar.txt", funcs.fnamemodify(meths.buf_get_name(0), ":t"))
    end)
    it('triggers CmdUndefined event if command is not found', function()
      meths.exec_lua([[
        vim.api.nvim_create_autocmd("CmdUndefined",
                                    { pattern = "Foo",
                                      callback = function()
                                        vim.api.nvim_create_user_command("Foo", "echo 'foo'", {})
                                      end
                                    })
      ]], {})
      eq("foo", meths.cmd({ cmd = "Foo" }, { output = true }))
    end)
    it('errors if command is not implemented', function()
      eq("Command not implemented: winpos", pcall_err(meths.cmd, { cmd = "winpos" }, {}))
    end)
    it('works with empty arguments list', function()
      meths.cmd({ cmd = "update" }, {})
      meths.cmd({ cmd = "buffer", count = 0 }, {})
    end)
    it('doesn\'t suppress errors when used in keymapping', function()
      meths.exec_lua([[
        vim.keymap.set("n", "[l",
                       function() vim.api.nvim_cmd({ cmd = "echo", args = {"foo"} }, {}) end)
      ]], {})
      feed("[l")
      neq(nil, string.find(eval("v:errmsg"), "E5108:"))
    end)
    it('handles 0 range #19608', function()
      meths.buf_set_lines(0, 0, -1, false, { "aa" })
      meths.cmd({ cmd = 'delete', range = { 0 } }, {})
      command('undo')
      eq({'aa'}, meths.buf_get_lines(0, 0, 1, false))
      assert_alive()
    end)
    it('supports filename expansion', function()
      meths.cmd({ cmd = 'argadd', args = { '%:p:h:t', '%:p:h:t' } }, {})
      local arg = funcs.expand('%:p:h:t')
      eq({ arg, arg }, funcs.argv())
    end)
    it("'make' command works when argument count isn't 1 #19696", function()
      command('set makeprg=echo')
      command('set shellquote=')
      matches('^:!echo ',
              meths.cmd({ cmd = 'make' }, { output = true }))
      assert_alive()
      matches('^:!echo foo bar',
              meths.cmd({ cmd = 'make', args = { 'foo', 'bar' } }, { output = true }))
      assert_alive()
      local arg_pesc = pesc(funcs.expand('%:p:h:t'))
      matches(('^:!echo %s %s'):format(arg_pesc, arg_pesc),
              meths.cmd({ cmd = 'make', args = { '%:p:h:t', '%:p:h:t' } }, { output = true }))
      assert_alive()
    end)
    it('doesn\'t display messages when output=true', function()
      local screen = Screen.new(40, 6)
      screen:attach()
      screen:set_default_attr_ids({
        [0] = {bold=true, foreground=Screen.colors.Blue},
      })
      meths.cmd({cmd = 'echo', args = {[['hello']]}}, {output = true})
      screen:expect{grid=[[
        ^                                        |
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
                                                |
      ]]}
      exec([[
        func Print()
          call nvim_cmd(#{cmd: 'echo', args: ['"hello"']}, #{output: v:true})
        endfunc
      ]])
      feed([[:echon 1 | call Print() | echon 5<CR>]])
      screen:expect{grid=[[
        ^                                        |
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        {0:~                                       }|
        15                                      |
      ]]}
    end)
    it('works with non-String args', function()
      eq('2', meths.cmd({cmd = 'echo', args = {2}}, {output = true}))
      eq('1', meths.cmd({cmd = 'echo', args = {true}}, {output = true}))
    end)
    describe('first argument as count', function()
      before_each(clear)

      it('works', function()
        command('vsplit | enew')
        meths.cmd({cmd = 'bdelete', args = {meths.get_current_buf()}}, {})
        eq(1, meths.get_current_buf().id)
      end)
      it('works with :sleep using milliseconds', function()
        local start = luv.now()
        meths.cmd({cmd = 'sleep', args = {'100m'}}, {})
        ok(luv.now() - start <= 300)
      end)
    end)
  end)
end)