Merge #9301 'runtime/lua'

21 files changed, 173 insertions, 161 deletions

diff --git a/runtime/lua/vim/shared.lua b/runtime/lua/vim/shared.lua
new file mode 100644
index 0000000000..9dca51ce9a
--- /dev/null
+++ b/runtime/lua/vim/shared.lua
@@ -0,0 +1,73 @@
+--- Shared functions
+--    - Used by Nvim and tests
+--    - Can run in vanilla Lua (do not require a running instance of Nvim)
+
+
+-- Checks if a list-like (vector) table contains `value`.
+local function tbl_contains(t, value)
+  if type(t) ~= 'table' then
+    error('t must be a table')
+  end
+  for _,v in ipairs(t) do
+    if v == value then
+      return true
+    end
+  end
+  return false
+end
+
+--- Merges two or more map-like tables.
+--
+--@see |extend()|
+--
+-- behavior: Decides what to do if a key is found in more than one map:
+--           "error": raise an error
+--           "keep":  use value from the leftmost map
+--           "force": use value from the rightmost map
+local function tbl_extend(behavior, ...)
+  if (behavior ~= 'error' and behavior ~= 'keep' and behavior ~= 'force') then
+    error('invalid "behavior": '..tostring(behavior))
+  end
+  local ret = {}
+  for i = 1, select('#', ...) do
+    local tbl = select(i, ...)
+    if tbl then
+      for k, v in pairs(tbl) do
+        if behavior ~= 'force' and ret[k] ~= nil then
+          if behavior == 'error' then
+            error('key found in more than one map: '..k)
+          end  -- Else behavior is "keep".
+        else
+          ret[k] = v
+        end
+      end
+    end
+  end
+  return ret
+end
+
+-- Flattens a list-like table: unrolls and appends nested tables to table `t`.
+local function tbl_flatten(t)
+  -- From https://github.com/premake/premake-core/blob/master/src/base/table.lua
+  local result = {}
+  local function _tbl_flatten(_t)
+    local n = #_t
+    for i = 1, n do
+      local v = _t[i]
+      if type(v) == "table" then
+        _tbl_flatten(v)
+      elseif v then
+        table.insert(result, v)
+      end
+    end
+  end
+  _tbl_flatten(t)
+  return result
+end
+
+local module = {
+  tbl_contains = tbl_contains,
+  tbl_extend = tbl_extend,
+  tbl_flatten = tbl_flatten,
+}
+return module
diff --git a/src/nvim/lua/vim.lua b/src/nvim/lua/vim.lua
index b0d0bfc74b..1a7aec6cc6 100644
--- a/src/nvim/lua/vim.lua
+++ b/src/nvim/lua/vim.lua
@@ -1,3 +1,39 @@
+-- Nvim-Lua stdlib: the `vim` module (:help lua-stdlib)
+--
+-- Lua code lives in one of three places:
+--    1. The runtime (`runtime/lua/vim/`). For "nice to have" features, e.g.
+--       the `inspect` and `lpeg` modules.
+--    2. The `vim.shared` module: code shared between Nvim and its test-suite.
+--    3. Compiled-into Nvim itself (`src/nvim/lua/`).
+--
+-- Guideline: "If in doubt, put it in the runtime".
+--
+-- Most functions should live directly on `vim.`, not sub-modules. The only
+-- "forbidden" names are those claimed by legacy `if_lua`:
+--    $ vim
+--    :lua for k,v in pairs(vim) do print(k) end
+--    buffer
+--    open
+--    window
+--    lastline
+--    firstline
+--    type
+--    line
+--    eval
+--    dict
+--    beep
+--    list
+--    command
+--
+-- Reference (#6580):
+--    - https://github.com/luafun/luafun
+--    - https://github.com/rxi/lume
+--    - http://leafo.net/lapis/reference/utilities.html
+--    - https://github.com/torch/paths
+--    - https://github.com/bakpakin/Fennel (pretty print, repl)
+--    - https://github.com/howl-editor/howl/tree/master/lib/howl/util
+
+
 -- Internal-only until comments in #8107 are addressed.
 -- Returns:
 --    {errcode}, {output}
@@ -187,10 +223,14 @@ deepcopy = function(orig)
   return deepcopy_funcs[type(orig)](orig)
 end
 
-local function __index(table, key)
-  if key == "inspect" then
-    table.inspect = require("vim.inspect")
-    return table.inspect
+local function __index(t, key)
+  if key == 'inspect' then
+    t.inspect = require('vim.inspect')
+    return t.inspect
+  elseif require('vim.shared')[key] ~= nil then
+    -- Expose all `vim.shared` functions on the `vim` module.
+    t[key] = require('vim.shared')[key]
+    return t[key]
   end
 end
 
diff --git a/src/nvim/testdir/load.vim b/src/nvim/testdir/load.vim
index 2e01338dd0..6369b8f45e 100644
--- a/src/nvim/testdir/load.vim
+++ b/src/nvim/testdir/load.vim
@@ -1,3 +1,5 @@
+" Also used by: test/functional/helpers.lua
+
 function! s:load_factor() abort
   let timeout = 200
   let times = []
@@ -23,8 +25,8 @@ function! s:load_factor() abort
 endfunction
 
 " Compute load factor only once.
-let s:load_factor = s:load_factor()
+let g:test_load_factor = s:load_factor()
 
 function! LoadAdjust(num) abort
-  return float2nr(ceil(a:num * s:load_factor))
+  return float2nr(ceil(a:num * g:test_load_factor))
 endfunction
diff --git a/src/nvim/testdir/test_timers.vim b/src/nvim/testdir/test_timers.vim
index 5b5f001e6b..9384989a35 100644
--- a/src/nvim/testdir/test_timers.vim
+++ b/src/nvim/testdir/test_timers.vim
@@ -15,17 +15,13 @@ func MyHandlerWithLists(lists, timer)
   let x = string(a:lists)
 endfunc
 
-func s:assert_inrange(lower, upper, actual)
-  return assert_inrange(a:lower, LoadAdjust(a:upper), a:actual)
-endfunc
-
 func Test_oneshot()
   let g:val = 0
   let timer = timer_start(50, 'MyHandler')
   let slept = WaitFor('g:val == 1')
   call assert_equal(1, g:val)
   if has('reltime')
-    call s:assert_inrange(40, 120, slept)
+    call assert_inrange(40, LoadAdjust(120), slept)
   else
     call assert_inrange(20, 120, slept)
   endif
@@ -37,7 +33,7 @@ func Test_repeat_three()
   let slept = WaitFor('g:val == 3')
   call assert_equal(3, g:val)
   if has('reltime')
-    call s:assert_inrange(120, 250, slept)
+    call assert_inrange(120, LoadAdjust(250), slept)
   else
     call assert_inrange(80, 200, slept)
   endif
@@ -52,7 +48,7 @@ func Test_repeat_many()
   endif
   sleep 200m
   call timer_stop(timer)
-  call s:assert_inrange((has('mac') ? 1 : 2), 4, g:val)
+  call assert_inrange((has('mac') ? 1 : 2), LoadAdjust(4), g:val)
 endfunc
 
 func Test_with_partial_callback()
@@ -66,7 +62,7 @@ func Test_with_partial_callback()
   let slept = WaitFor('g:val == 1')
   call assert_equal(1, g:val)
   if has('reltime')
-    call s:assert_inrange(40, 130, slept)
+    call assert_inrange(40, LoadAdjust(130), slept)
   else
     call assert_inrange(20, 100, slept)
   endif
@@ -129,7 +125,7 @@ func Test_paused()
   let slept = WaitFor('g:val == 1')
   call assert_equal(1, g:val)
   if has('reltime')
-    call s:assert_inrange(0, 140, slept)
+    call assert_inrange(0, LoadAdjust(140), slept)
   else
     call assert_inrange(0, 10, slept)
   endif
diff --git a/test/functional/api/keymap_spec.lua b/test/functional/api/keymap_spec.lua
index c150787425..b3f6bb7895 100644
--- a/test/functional/api/keymap_spec.lua
+++ b/test/functional/api/keymap_spec.lua
@@ -1,5 +1,4 @@
 local helpers = require('test.functional.helpers')(after_each)
-local global_helpers = require('test.helpers')
 
 local bufmeths = helpers.bufmeths
 local clear = helpers.clear
@@ -12,8 +11,8 @@ local funcs = helpers.funcs
 local meths = helpers.meths
 local source = helpers.source
 
-local shallowcopy = global_helpers.shallowcopy
-local sleep = global_helpers.sleep
+local shallowcopy = helpers.shallowcopy
+local sleep = helpers.sleep
 
 describe('nvim_get_keymap', function()
   before_each(clear)
diff --git a/test/functional/api/server_requests_spec.lua b/test/functional/api/server_requests_spec.lua
index 4d25ba0819..7d9a8269d9 100644
--- a/test/functional/api/server_requests_spec.lua
+++ b/test/functional/api/server_requests_spec.lua
@@ -1,7 +1,6 @@
 -- Test server -> client RPC scenarios. Note: unlike `rpcnotify`, to evaluate
 -- `rpcrequest` calls we need the client event loop to be running.
 local helpers = require('test.functional.helpers')(after_each)
-local Paths = require('test.config.paths')
 
 local clear, nvim, eval = helpers.clear, helpers.nvim, helpers.eval
 local eq, neq, run, stop = helpers.eq, helpers.neq, helpers.run, helpers.stop
@@ -243,8 +242,8 @@ describe('server -> client', function()
         \ 'rpc': v:true
         \ }
       ]])
-      local lua_prog = Paths.test_lua_prg
-      meths.set_var("args", {lua_prog, 'test/functional/api/rpc_fixture.lua'})
+      meths.set_var("args", {helpers.test_lua_prg,
+                             'test/functional/api/rpc_fixture.lua'})
       jobid = eval("jobstart(g:args, g:job_opts)")
       neq(0, 'jobid')
     end)
diff --git a/test/functional/api/vim_spec.lua b/test/functional/api/vim_spec.lua
index 2178abab53..a7d8dc59ec 100644
--- a/test/functional/api/vim_spec.lua
+++ b/test/functional/api/vim_spec.lua
@@ -1,6 +1,5 @@
 local helpers = require('test.functional.helpers')(after_each)
 local Screen = require('test.functional.ui.screen')
-local global_helpers = require('test.helpers')
 
 local NIL = helpers.NIL
 local clear, nvim, eq, neq = helpers.clear, helpers.nvim, helpers.eq, helpers.neq
@@ -16,10 +15,10 @@ local request = helpers.request
 local source = helpers.source
 local next_msg = helpers.next_msg
 
-local expect_err = global_helpers.expect_err
-local format_string = global_helpers.format_string
-local intchar2lua = global_helpers.intchar2lua
-local mergedicts_copy = global_helpers.mergedicts_copy
+local expect_err = helpers.expect_err
+local format_string = helpers.format_string
+local intchar2lua = helpers.intchar2lua
+local mergedicts_copy = helpers.mergedicts_copy
 
 describe('API', function()
   before_each(clear)
diff --git a/test/functional/core/channels_spec.lua b/test/functional/core/channels_spec.lua
index 0137092eb5..ddaed1c448 100644
--- a/test/functional/core/channels_spec.lua
+++ b/test/functional/core/channels_spec.lua
@@ -1,7 +1,5 @@
-local global_helpers = require('test.helpers')
-local uname = global_helpers.uname
-
 local helpers = require('test.functional.helpers')(after_each)
+local uname = helpers.uname
 local clear, eq, eval, next_msg, ok, source = helpers.clear, helpers.eq,
    helpers.eval, helpers.next_msg, helpers.ok, helpers.source
 local command, funcs, meths = helpers.command, helpers.funcs, helpers.meths
diff --git a/test/functional/eval/let_spec.lua b/test/functional/eval/let_spec.lua
index 0cbf40137e..63e18f943f 100644
--- a/test/functional/eval/let_spec.lua
+++ b/test/functional/eval/let_spec.lua
@@ -59,7 +59,7 @@ describe(':let', function()
   end)
 
   it("multibyte env var to child process #8398 #9267",  function()
-    if (not helpers.iswin()) and require('test.helpers').isCI() then
+    if (not helpers.iswin()) and helpers.isCI() then
       -- Fails on non-Windows CI. Buffering/timing issue?
       pending('fails on unix CI', function() end)
     end
diff --git a/test/functional/helpers.lua b/test/functional/helpers.lua
index fd10a6afcd..35084f6cff 100644
--- a/test/functional/helpers.lua
+++ b/test/functional/helpers.lua
@@ -8,23 +8,14 @@ local Session = require('nvim.session')
 local TcpStream = require('nvim.tcp_stream')
 local SocketStream = require('nvim.socket_stream')
 local ChildProcessStream = require('nvim.child_process_stream')
-local Paths = require('test.config.paths')
 
 local check_cores = global_helpers.check_cores
 local check_logs = global_helpers.check_logs
 local dedent = global_helpers.dedent
 local eq = global_helpers.eq
-local expect_err = global_helpers.expect_err
-local filter = global_helpers.filter
-local map = global_helpers.map
-local matches = global_helpers.matches
-local near = global_helpers.near
-local neq = global_helpers.neq
 local ok = global_helpers.ok
-local read_file = global_helpers.read_file
 local sleep = global_helpers.sleep
-local table_contains = global_helpers.table_contains
-local table_flatten = global_helpers.table_flatten
+local tbl_contains = global_helpers.tbl_contains
 local write_file = global_helpers.write_file
 
 local start_dir = lfs.currentdir()
@@ -32,7 +23,7 @@ local start_dir = lfs.currentdir()
 local nvim_prog = (
   os.getenv('NVIM_PROG')
   or os.getenv('NVIM_PRG')
-  or Paths.test_build_dir .. '/bin/nvim'
+  or global_helpers.test_build_dir .. '/bin/nvim'
 )
 -- Default settings for the test session.
 local nvim_set  = 'set shortmess+=I background=light noswapfile noautoindent'
@@ -174,7 +165,7 @@ local function expect_msg_seq(...)
         error(cat_err(final_error,
                       string.format('got %d messages (ignored %d), expected %d',
                                     #actual_seq, nr_ignored, #expected_seq)))
-      elseif table_contains(ignore, msg_type) then
+      elseif tbl_contains(ignore, msg_type) then
         nr_ignored = nr_ignored + 1
       else
         table.insert(actual_seq, msg)
@@ -348,9 +339,9 @@ local function remove_args(args, args_rm)
   end
   local last = ''
   for _, arg in ipairs(args) do
-    if table_contains(skip_following, last) then
+    if tbl_contains(skip_following, last) then
       last = ''
-    elseif table_contains(args_rm, arg) then
+    elseif tbl_contains(args_rm, arg) then
       last = arg
     else
       table.insert(new_args, arg)
@@ -747,41 +738,14 @@ local function alter_slashes(obj)
   end
 end
 
-local function compute_load_factor()
-  local timeout = 200
-  local times = {}
-
-  clear()
-
-  for _ = 1, 5 do
-    source([[
-      let g:val = 0
-      call timer_start(200, {-> nvim_set_var('val', 1)})
-      let start = reltime()
-      while 1
-        sleep 10m
-        if g:val == 1
-          let g:waited_in_ms = float2nr(reltimefloat(reltime(start)) * 1000)
-          break
-        endif
-      endwhile
-    ]])
-    table.insert(times, nvim_eval('g:waited_in_ms'))
-  end
-
-  session:close()
-  session = nil
-
-  local longest = math.max(unpack(times))
-  local factor = (longest + 50.0) / timeout
-
-  return factor
-end
-
--- Compute load factor only once.
-local load_factor = compute_load_factor()
 
+local load_factor = nil
 local function load_adjust(num)
+  if load_factor == nil then  -- Compute load factor only once.
+    clear()
+    request('nvim_command', 'source src/nvim/testdir/load.vim')
+    load_factor = request('nvim_eval', 'g:test_load_factor')
+  end
   return math.ceil(num * load_factor)
 end
 
@@ -802,33 +766,25 @@ local module = {
   curtabmeths = curtabmeths,
   curwin = curwin,
   curwinmeths = curwinmeths,
-  dedent = dedent,
-  eq = eq,
   eval = nvim_eval,
   exc_exec = exc_exec,
   expect = expect,
   expect_any = expect_any,
-  expect_err = expect_err,
   expect_msg_seq = expect_msg_seq,
   expect_twostreams = expect_twostreams,
   feed = feed,
   feed_command = feed_command,
-  filter = filter,
   funcs = funcs,
   get_pathsep = get_pathsep,
   get_session = get_session,
   insert = insert,
   iswin = iswin,
-  map = map,
-  matches = matches,
   merge_args = merge_args,
   meth_pcall = meth_pcall,
   meths = meths,
   missing_provider = missing_provider,
   mkdir = lfs.mkdir,
   load_adjust = load_adjust,
-  near = near,
-  neq = neq,
   new_pipename = new_pipename,
   next_msg = next_msg,
   nvim = nvim,
@@ -838,13 +794,11 @@ local module = {
   nvim_prog = nvim_prog,
   nvim_prog_abs = nvim_prog_abs,
   nvim_set = nvim_set,
-  ok = ok,
   os_name = os_name,
   pathroot = pathroot,
   pending_win32 = pending_win32,
   prepend_argv = prepend_argv,
   rawfeed = rawfeed,
-  read_file = read_file,
   redir_exec = redir_exec,
   request = request,
   retry = retry,
@@ -854,20 +808,17 @@ local module = {
   set_session = set_session,
   set_shell_powershell = set_shell_powershell,
   skip_fragile = skip_fragile,
-  sleep = sleep,
   source = source,
   spawn = spawn,
   stop = stop,
-  table_flatten = table_flatten,
   tabmeths = tabmeths,
   tabpage = tabpage,
-  tmpname = tmpname,
   uimeths = uimeths,
   wait = wait,
   window = window,
   winmeths = winmeths,
-  write_file = write_file,
 }
+module = global_helpers.tbl_extend('error', module, global_helpers)
 
 return function(after_each)
   if after_each then
diff --git a/test/functional/options/defaults_spec.lua b/test/functional/options/defaults_spec.lua
index 0fc2876d00..415b526051 100644
--- a/test/functional/options/defaults_spec.lua
+++ b/test/functional/options/defaults_spec.lua
@@ -1,5 +1,4 @@
 local helpers = require('test.functional.helpers')(after_each)
-local global_helpers = require('test.helpers')
 
 local Screen = require('test.functional.ui.screen')
 
@@ -16,7 +15,7 @@ local neq = helpers.neq
 local mkdir = helpers.mkdir
 local rmdir = helpers.rmdir
 local alter_slashes = helpers.alter_slashes
-local table_contains = global_helpers.table_contains
+local tbl_contains = helpers.tbl_contains
 
 describe('startup defaults', function()
   describe(':filetype', function()
@@ -262,7 +261,7 @@ describe('XDG-based defaults', function()
 
     for _,v in ipairs(rtp) do
       local m = string.match(v, [=[[/\]nvim[^/\]*[/\]site.*$]=])
-      if m and not table_contains(rv, m) then
+      if m and not tbl_contains(rv, m) then
         table.insert(rv, m)
       end
     end
diff --git a/test/functional/terminal/tui_spec.lua b/test/functional/terminal/tui_spec.lua
index 469d088c57..56d6f68b7a 100644
--- a/test/functional/terminal/tui_spec.lua
+++ b/test/functional/terminal/tui_spec.lua
@@ -1,8 +1,7 @@
 -- TUI acceptance tests.
 -- Uses :terminal as a way to send keys and assert screen state.
-local global_helpers = require('test.helpers')
-local uname = global_helpers.uname
 local helpers = require('test.functional.helpers')(after_each)
+local uname = helpers.uname
 local thelpers = require('test.functional.terminal.helpers')
 local Screen = require('test.functional.ui.screen')
 local eq = helpers.eq
diff --git a/test/functional/ui/options_spec.lua b/test/functional/ui/options_spec.lua
index 7ce21f5d76..93192934c7 100644
--- a/test/functional/ui/options_spec.lua
+++ b/test/functional/ui/options_spec.lua
@@ -1,10 +1,9 @@
-local global_helpers = require('test.helpers')
 local helpers = require('test.functional.helpers')(after_each)
 local Screen = require('test.functional.ui.screen')
 local clear = helpers.clear
 local command = helpers.command
 local eq = helpers.eq
-local shallowcopy = global_helpers.shallowcopy
+local shallowcopy = helpers.shallowcopy
 
 describe('ui receives option updates', function()
   local screen
diff --git a/test/functional/ui/screen.lua b/test/functional/ui/screen.lua
index 53b6642207..a81851cbba 100644
--- a/test/functional/ui/screen.lua
+++ b/test/functional/ui/screen.lua
@@ -71,11 +71,10 @@
 -- To help write screen tests, see Screen:snapshot_util().
 -- To debug screen tests, see Screen:redraw_debug().
 
-local global_helpers = require('test.helpers')
-local deepcopy = global_helpers.deepcopy
-local shallowcopy = global_helpers.shallowcopy
-local concat_tables = global_helpers.concat_tables
 local helpers = require('test.functional.helpers')(nil)
+local deepcopy = helpers.deepcopy
+local shallowcopy = helpers.shallowcopy
+local concat_tables = helpers.concat_tables
 local request, run_session = helpers.request, helpers.run_session
 local eq = helpers.eq
 local dedent = helpers.dedent
diff --git a/test/functional/ui/wildmode_spec.lua b/test/functional/ui/wildmode_spec.lua
index 1c8854bb28..f4b80fd428 100644
--- a/test/functional/ui/wildmode_spec.lua
+++ b/test/functional/ui/wildmode_spec.lua
@@ -1,7 +1,6 @@
-local global_helpers = require('test.helpers')
-local shallowcopy = global_helpers.shallowcopy
 local helpers = require('test.functional.helpers')(after_each)
 local Screen = require('test.functional.ui.screen')
+local shallowcopy = helpers.shallowcopy
 local clear, feed, command = helpers.clear, helpers.feed, helpers.command
 local iswin = helpers.iswin
 local funcs = helpers.funcs
diff --git a/test/helpers.lua b/test/helpers.lua
index 89cf13f917..cc5f05bdee 100644
--- a/test/helpers.lua
+++ b/test/helpers.lua
@@ -1,8 +1,10 @@
 require('vim.compat')
+local shared = require('vim.shared')
 local assert = require('luassert')
 local luv = require('luv')
 local lfs = require('lfs')
 local relpath = require('pl.path').relpath
+local Paths = require('test.config.paths')
 
 local quote_me = '[^.%w%+%-%@%_%/]' -- complement (needn't quote)
 local function shell_quote(str)
@@ -420,6 +422,7 @@ local function updated(d, d2)
   return d
 end
 
+-- Concat list-like tables.
 local function concat_tables(...)
   local ret = {}
   for i = 1, select('#', ...) do
@@ -609,37 +612,6 @@ local function fixtbl_rec(tbl)
   return fixtbl(tbl)
 end
 
--- From https://github.com/premake/premake-core/blob/master/src/base/table.lua
-local function table_flatten(arr)
-  local result = {}
-  local function _table_flatten(_arr)
-    local n = #_arr
-    for i = 1, n do
-      local v = _arr[i]
-      if type(v) == "table" then
-        _table_flatten(v)
-      elseif v then
-        table.insert(result, v)
-      end
-    end
-  end
-  _table_flatten(arr)
-  return result
-end
-
--- Checks if a list-like (vector) table contains `value`.
-local function table_contains(t, value)
-  if type(t) ~= 'table' then
-    error('t must be a table')
-  end
-  for _,v in ipairs(t) do
-    if v == value then
-      return true
-    end
-  end
-  return false
-end
-
 local function hexdump(str)
   local len = string.len(str)
   local dump = ""
@@ -784,13 +756,12 @@ local module = {
   repeated_read_cmd = repeated_read_cmd,
   shallowcopy = shallowcopy,
   sleep = sleep,
-  table_contains = table_contains,
-  table_flatten = table_flatten,
   tmpname = tmpname,
   uname = uname,
   updated = updated,
   which = which,
   write_file = write_file,
 }
+module = shared.tbl_extend('error', module, Paths, shared)
 
 return module
diff --git a/test/unit/eval/typval_spec.lua b/test/unit/eval/typval_spec.lua
index 919a42fbb9..4535d6a0b2 100644
--- a/test/unit/eval/typval_spec.lua
+++ b/test/unit/eval/typval_spec.lua
@@ -1,7 +1,6 @@
 local bit = require('bit')
 local helpers = require('test.unit.helpers')(after_each)
 local eval_helpers = require('test.unit.eval.helpers')
-local global_helpers = require('test.helpers')
 
 local itp = helpers.gen_itp(it)
 
@@ -14,6 +13,8 @@ local NULL = helpers.NULL
 local cimport = helpers.cimport
 local to_cstr = helpers.to_cstr
 local alloc_log_new = helpers.alloc_log_new
+local concat_tables = helpers.concat_tables
+local map = helpers.map
 
 local a = eval_helpers.alloc_logging_helpers
 local int = eval_helpers.int
@@ -40,9 +41,6 @@ local callback2tbl = eval_helpers.callback2tbl
 local tbl2callback = eval_helpers.tbl2callback
 local dict_watchers = eval_helpers.dict_watchers
 
-local concat_tables = global_helpers.concat_tables
-local map = global_helpers.map
-
 local lib = cimport('./src/nvim/eval/typval.h', './src/nvim/memory.h',
                     './src/nvim/mbyte.h', './src/nvim/garray.h',
                     './src/nvim/eval.h', './src/nvim/vim.h',
diff --git a/test/unit/helpers.lua b/test/unit/helpers.lua
index beb25f25db..e634b7296e 100644
--- a/test/unit/helpers.lua
+++ b/test/unit/helpers.lua
@@ -15,7 +15,6 @@ local dedent = global_helpers.dedent
 local neq = global_helpers.neq
 local map = global_helpers.map
 local eq = global_helpers.eq
-local ok = global_helpers.ok
 
 -- C constants.
 local NULL = ffi.cast('void*', 0)
@@ -842,9 +841,6 @@ local module = {
   cimport = cimport,
   cppimport = cppimport,
   internalize = internalize,
-  ok = ok,
-  eq = eq,
-  neq = neq,
   ffi = ffi,
   lib = lib,
   cstr = cstr,
@@ -869,6 +865,7 @@ local module = {
   ptr2key = ptr2key,
   debug_log = debug_log,
 }
+module = global_helpers.tbl_extend('error', module, global_helpers)
 return function()
   return module
 end
diff --git a/test/unit/undo_spec.lua b/test/unit/undo_spec.lua
index f23110b329..616c6fbe3d 100644
--- a/test/unit/undo_spec.lua
+++ b/test/unit/undo_spec.lua
@@ -2,9 +2,7 @@ local helpers = require('test.unit.helpers')(after_each)
 local itp = helpers.gen_itp(it)
 local lfs = require('lfs')
 local child_call_once = helpers.child_call_once
-
-local global_helpers = require('test.helpers')
-local sleep = global_helpers.sleep
+local sleep = helpers.sleep
 
 local ffi = helpers.ffi
 local cimport = helpers.cimport
@@ -156,12 +154,12 @@ describe('u_write_undo', function()
     local file_contents = "testing permissions"
     -- Write a text file where the undofile should go
     local correct_name = ffi.string(undo.u_get_undo_file_name(file_buffer.b_ffname, false))
-    global_helpers.write_file(correct_name, file_contents, true, false)
+    helpers.write_file(correct_name, file_contents, true, false)
 
     -- Call with `forceit`.
     u_write_undo(correct_name, true, file_buffer, buffer_hash)
 
-    local undo_file_contents = global_helpers.read_file(correct_name)
+    local undo_file_contents = helpers.read_file(correct_name)
 
     neq(file_contents, undo_file_contents)
     local success, deletion_err = os.remove(correct_name)  -- delete the file now that we're done with it.
diff --git a/test/unit/viml/expressions/lexer_spec.lua b/test/unit/viml/expressions/lexer_spec.lua
index 1b57a24ad5..358e858d61 100644
--- a/test/unit/viml/expressions/lexer_spec.lua
+++ b/test/unit/viml/expressions/lexer_spec.lua
@@ -1,5 +1,4 @@
 local helpers = require('test.unit.helpers')(after_each)
-local global_helpers = require('test.helpers')
 local itp = helpers.gen_itp(it)
 local viml_helpers = require('test.unit.viml.helpers')
 
@@ -8,6 +7,8 @@ local conv_enum = helpers.conv_enum
 local cimport = helpers.cimport
 local ffi = helpers.ffi
 local eq = helpers.eq
+local shallowcopy = helpers.shallowcopy
+local intchar2lua = helpers.intchar2lua
 
 local conv_ccs = viml_helpers.conv_ccs
 local new_pstate = viml_helpers.new_pstate
@@ -15,9 +16,6 @@ local conv_cmp_type = viml_helpers.conv_cmp_type
 local pstate_set_str = viml_helpers.pstate_set_str
 local conv_expr_asgn_type = viml_helpers.conv_expr_asgn_type
 
-local shallowcopy = global_helpers.shallowcopy
-local intchar2lua = global_helpers.intchar2lua
-
 local lib = cimport('./src/nvim/viml/parser/expressions.h')
 
 local eltkn_type_tab, eltkn_mul_type_tab, eltkn_opt_scope_tab
diff --git a/test/unit/viml/expressions/parser_spec.lua b/test/unit/viml/expressions/parser_spec.lua
index 73388e5dd2..a8f29529ec 100644
--- a/test/unit/viml/expressions/parser_spec.lua
+++ b/test/unit/viml/expressions/parser_spec.lua
@@ -1,5 +1,4 @@
 local helpers = require('test.unit.helpers')(after_each)
-local global_helpers = require('test.helpers')
 local itp = helpers.gen_itp(it)
 local viml_helpers = require('test.unit.viml.helpers')
 
@@ -14,6 +13,11 @@ local cimport = helpers.cimport
 local ffi = helpers.ffi
 local neq = helpers.neq
 local eq = helpers.eq
+local mergedicts_copy = helpers.mergedicts_copy
+local format_string = helpers.format_string
+local format_luav = helpers.format_luav
+local intchar2lua = helpers.intchar2lua
+local dictdiff = helpers.dictdiff
 
 local conv_ccs = viml_helpers.conv_ccs
 local new_pstate = viml_helpers.new_pstate
@@ -21,12 +25,6 @@ local conv_cmp_type = viml_helpers.conv_cmp_type
 local pstate_set_str = viml_helpers.pstate_set_str
 local conv_expr_asgn_type = viml_helpers.conv_expr_asgn_type
 
-local mergedicts_copy = global_helpers.mergedicts_copy
-local format_string = global_helpers.format_string
-local format_luav = global_helpers.format_luav
-local intchar2lua = global_helpers.intchar2lua
-local dictdiff = global_helpers.dictdiff
-
 local lib = cimport('./src/nvim/viml/parser/expressions.h',
                     './src/nvim/syntax.h')