neovim/test/unit/testutil.lua
Justin M. Keyes 8886b1807c
refactor(lua): "module" => "M" #28426
Most of the codebase uses the `M` convention for Lua module.
Update the last remaining cases.
2024-04-20 09:06:49 -07:00

913 lines
24 KiB
Lua

local ffi = require('ffi')
local formatc = require('test.unit.formatc')
local Set = require('test.unit.set')
local Preprocess = require('test.unit.preprocess')
local t_global = require('test.testutil')
local paths = t_global.paths
local assert = require('luassert')
local say = require('say')
local check_cores = t_global.check_cores
local dedent = t_global.dedent
local neq = t_global.neq
local map = vim.tbl_map
local eq = t_global.eq
local trim = vim.trim
-- add some standard header locations
for _, p in ipairs(paths.include_paths) do
Preprocess.add_to_include_path(p)
end
local child_pid = nil --- @type integer?
--- @generic F: function
--- @param func F
--- @return F
local function only_separate(func)
return function(...)
if child_pid ~= 0 then
error('This function must be run in a separate process only')
end
return func(...)
end
end
--- @class ChildCall
--- @field func function
--- @field args any[]
--- @class ChildCallLog
--- @field func string
--- @field args any[]
--- @field ret any?
local child_calls_init = {} --- @type ChildCall[]
local child_calls_mod = nil --- @type ChildCall[]
local child_calls_mod_once = nil --- @type ChildCall[]?
local function child_call(func, ret)
return function(...)
local child_calls = child_calls_mod or child_calls_init
if child_pid ~= 0 then
child_calls[#child_calls + 1] = { func = func, args = { ... } }
return ret
else
return func(...)
end
end
end
-- Run some code at the start of the child process, before running the test
-- itself. Is supposed to be run in `before_each`.
--- @param func function
local function child_call_once(func, ...)
if child_pid ~= 0 then
child_calls_mod_once[#child_calls_mod_once + 1] = { func = func, args = { ... } }
else
func(...)
end
end
local child_cleanups_mod_once = nil --- @type ChildCall[]?
-- Run some code at the end of the child process, before exiting. Is supposed to
-- be run in `before_each` because `after_each` is run after child has exited.
local function child_cleanup_once(func, ...)
local child_cleanups = child_cleanups_mod_once
if child_pid ~= 0 then
child_cleanups[#child_cleanups + 1] = { func = func, args = { ... } }
else
func(...)
end
end
-- Unittests are run from debug nvim binary in lua interpreter mode.
local libnvim = ffi.C
local lib = setmetatable({}, {
__index = only_separate(function(_, idx)
return libnvim[idx]
end),
__newindex = child_call(function(_, idx, val)
libnvim[idx] = val
end),
})
local init = only_separate(function()
for _, c in ipairs(child_calls_init) do
c.func(unpack(c.args))
end
libnvim.event_init()
libnvim.early_init(nil)
if child_calls_mod then
for _, c in ipairs(child_calls_mod) do
c.func(unpack(c.args))
end
end
if child_calls_mod_once then
for _, c in ipairs(child_calls_mod_once) do
c.func(unpack(c.args))
end
child_calls_mod_once = nil
end
end)
local deinit = only_separate(function()
if child_cleanups_mod_once then
for _, c in ipairs(child_cleanups_mod_once) do
c.func(unpack(c.args))
end
child_cleanups_mod_once = nil
end
end)
-- a Set that keeps around the lines we've already seen
local cdefs_init = Set:new()
local cdefs_mod = nil
local imported = Set:new()
local pragma_pack_id = 1
-- some things are just too complex for the LuaJIT C parser to digest. We
-- usually don't need them anyway.
--- @param body string
local function filter_complex_blocks(body)
local result = {} --- @type string[]
for line in body:gmatch('[^\r\n]+') do
if
not (
string.find(line, '(^)', 1, true) ~= nil
or string.find(line, '_ISwupper', 1, true)
or string.find(line, '_Float')
or string.find(line, '__s128')
or string.find(line, '__u128')
or string.find(line, 'msgpack_zone_push_finalizer')
or string.find(line, 'msgpack_unpacker_reserve_buffer')
or string.find(line, 'value_init_')
or string.find(line, 'UUID_NULL') -- static const uuid_t UUID_NULL = {...}
or string.find(line, 'inline _Bool')
-- used by macOS headers
or string.find(line, 'typedef enum : ')
or string.find(line, 'mach_vm_range_recipe')
)
then
result[#result + 1] = line
end
end
return table.concat(result, '\n')
end
local cdef = ffi.cdef
local cimportstr
local previous_defines_init = [[
typedef struct { char bytes[16]; } __attribute__((aligned(16))) __uint128_t;
typedef struct { char bytes[16]; } __attribute__((aligned(16))) __float128;
]]
local preprocess_cache_init = {} --- @type table<string,string>
local previous_defines_mod = ''
local preprocess_cache_mod = nil --- @type table<string,string>
local function is_child_cdefs()
return os.getenv('NVIM_TEST_MAIN_CDEFS') ~= '1'
end
-- use this helper to import C files, you can pass multiple paths at once,
-- this helper will return the C namespace of the nvim library.
local function cimport(...)
local previous_defines --- @type string
local preprocess_cache --- @type table<string,string>
local cdefs
if is_child_cdefs() and preprocess_cache_mod then
preprocess_cache = preprocess_cache_mod
previous_defines = previous_defines_mod
cdefs = cdefs_mod
else
preprocess_cache = preprocess_cache_init
previous_defines = previous_defines_init
cdefs = cdefs_init
end
for _, path in ipairs({ ... }) do
if not (path:sub(1, 1) == '/' or path:sub(1, 1) == '.' or path:sub(2, 2) == ':') then
path = './' .. path
end
if not preprocess_cache[path] then
local body --- @type string
body, previous_defines = Preprocess.preprocess(previous_defines, path)
-- format it (so that the lines are "unique" statements), also filter out
-- Objective-C blocks
if os.getenv('NVIM_TEST_PRINT_I') == '1' then
local lnum = 0
for line in body:gmatch('[^\n]+') do
lnum = lnum + 1
print(lnum, line)
end
end
body = formatc(body)
body = filter_complex_blocks(body)
-- add the formatted lines to a set
local new_cdefs = Set:new()
for line in body:gmatch('[^\r\n]+') do
line = trim(line)
-- give each #pragma pack a unique id, so that they don't get removed
-- if they are inserted into the set
-- (they are needed in the right order with the struct definitions,
-- otherwise luajit has wrong memory layouts for the structs)
if line:match('#pragma%s+pack') then
--- @type string
line = line .. ' // ' .. pragma_pack_id
pragma_pack_id = pragma_pack_id + 1
end
new_cdefs:add(line)
end
-- subtract the lines we've already imported from the new lines, then add
-- the new unique lines to the old lines (so they won't be imported again)
new_cdefs:diff(cdefs)
cdefs:union(new_cdefs)
-- request a sorted version of the new lines (same relative order as the
-- original preprocessed file) and feed that to the LuaJIT ffi
local new_lines = new_cdefs:to_table()
if os.getenv('NVIM_TEST_PRINT_CDEF') == '1' then
for lnum, line in ipairs(new_lines) do
print(lnum, line)
end
end
body = table.concat(new_lines, '\n')
preprocess_cache[path] = body
end
cimportstr(preprocess_cache, path)
end
return lib
end
local function cimport_immediate(...)
local saved_pid = child_pid
child_pid = 0
local err, emsg = pcall(cimport, ...)
child_pid = saved_pid
if not err then
io.stderr:write(tostring(emsg) .. '\n')
assert(false)
else
return lib
end
end
--- @param preprocess_cache table<string,string[]>
--- @param path string
local function _cimportstr(preprocess_cache, path)
if imported:contains(path) then
return lib
end
local body = preprocess_cache[path]
if body == '' then
return lib
end
cdef(body)
imported:add(path)
return lib
end
if is_child_cdefs() then
cimportstr = child_call(_cimportstr, lib)
else
cimportstr = _cimportstr
end
local function alloc_log_new()
local log = {
log = {}, --- @type ChildCallLog[]
lib = cimport('./src/nvim/memory.h'), --- @type table<string,function>
original_functions = {}, --- @type table<string,function>
null = { ['\0:is_null'] = true },
}
local allocator_functions = { 'malloc', 'free', 'calloc', 'realloc' }
function log:save_original_functions()
for _, funcname in ipairs(allocator_functions) do
if not self.original_functions[funcname] then
self.original_functions[funcname] = self.lib['mem_' .. funcname]
end
end
end
log.save_original_functions = child_call(log.save_original_functions)
function log:set_mocks()
for _, k in ipairs(allocator_functions) do
do
local kk = k
self.lib['mem_' .. k] = function(...)
--- @type ChildCallLog
local log_entry = { func = kk, args = { ... } }
self.log[#self.log + 1] = log_entry
if kk == 'free' then
self.original_functions[kk](...)
else
log_entry.ret = self.original_functions[kk](...)
end
for i, v in ipairs(log_entry.args) do
if v == nil then
-- XXX This thing thinks that {NULL} ~= {NULL}.
log_entry.args[i] = self.null
end
end
if self.hook then
self:hook(log_entry)
end
if log_entry.ret then
return log_entry.ret
end
end
end
end
end
log.set_mocks = child_call(log.set_mocks)
function log:clear()
self.log = {}
end
function log:check(exp)
eq(exp, self.log)
self:clear()
end
function log:clear_tmp_allocs(clear_null_frees)
local toremove = {} --- @type integer[]
local allocs = {} --- @type table<string,integer>
for i, v in ipairs(self.log) do
if v.func == 'malloc' or v.func == 'calloc' then
allocs[tostring(v.ret)] = i
elseif v.func == 'realloc' or v.func == 'free' then
if allocs[tostring(v.args[1])] then
toremove[#toremove + 1] = allocs[tostring(v.args[1])]
if v.func == 'free' then
toremove[#toremove + 1] = i
end
elseif clear_null_frees and v.args[1] == self.null then
toremove[#toremove + 1] = i
end
if v.func == 'realloc' then
allocs[tostring(v.ret)] = i
end
end
end
table.sort(toremove)
for i = #toremove, 1, -1 do
table.remove(self.log, toremove[i])
end
end
function log:setup()
log:save_original_functions()
log:set_mocks()
end
function log:before_each() end
function log:after_each() end
log:setup()
return log
end
-- take a pointer to a C-allocated string and return an interned
-- version while also freeing the memory
local function internalize(cdata, len)
ffi.gc(cdata, ffi.C.free)
return ffi.string(cdata, len)
end
local cstr = ffi.typeof('char[?]')
local function to_cstr(string)
return cstr(#string + 1, string)
end
cimport_immediate('./test/unit/fixtures/posix.h')
local sc = {}
function sc.fork()
return tonumber(ffi.C.fork())
end
function sc.pipe()
local ret = ffi.new('int[2]', { -1, -1 })
ffi.errno(0)
local res = ffi.C.pipe(ret)
if res ~= 0 then
local err = ffi.errno(0)
assert(res == 0, ('pipe() error: %u: %s'):format(err, ffi.string(ffi.C.strerror(err))))
end
assert(ret[0] ~= -1 and ret[1] ~= -1)
return ret[0], ret[1]
end
--- @return string
function sc.read(rd, len)
local ret = ffi.new('char[?]', len, { 0 })
local total_bytes_read = 0
ffi.errno(0)
while total_bytes_read < len do
local bytes_read =
tonumber(ffi.C.read(rd, ffi.cast('void*', ret + total_bytes_read), len - total_bytes_read))
if bytes_read == -1 then
local err = ffi.errno(0)
if err ~= ffi.C.kPOSIXErrnoEINTR then
assert(false, ('read() error: %u: %s'):format(err, ffi.string(ffi.C.strerror(err))))
end
elseif bytes_read == 0 then
break
else
total_bytes_read = total_bytes_read + bytes_read
end
end
return ffi.string(ret, total_bytes_read)
end
function sc.write(wr, s)
local wbuf = to_cstr(s)
local total_bytes_written = 0
ffi.errno(0)
while total_bytes_written < #s do
local bytes_written = tonumber(
ffi.C.write(wr, ffi.cast('void*', wbuf + total_bytes_written), #s - total_bytes_written)
)
if bytes_written == -1 then
local err = ffi.errno(0)
if err ~= ffi.C.kPOSIXErrnoEINTR then
assert(
false,
("write() error: %u: %s ('%s')"):format(err, ffi.string(ffi.C.strerror(err)), s)
)
end
elseif bytes_written == 0 then
break
else
total_bytes_written = total_bytes_written + bytes_written
end
end
return total_bytes_written
end
sc.close = ffi.C.close
--- @param pid integer
--- @return integer
function sc.wait(pid)
ffi.errno(0)
local stat_loc = ffi.new('int[1]', { 0 })
while true do
local r = ffi.C.waitpid(pid, stat_loc, ffi.C.kPOSIXWaitWUNTRACED)
if r == -1 then
local err = ffi.errno(0)
if err == ffi.C.kPOSIXErrnoECHILD then
break
elseif err ~= ffi.C.kPOSIXErrnoEINTR then
assert(false, ('waitpid() error: %u: %s'):format(err, ffi.string(ffi.C.strerror(err))))
end
else
assert(r == pid)
end
end
return stat_loc[0]
end
sc.exit = ffi.C._exit
--- @param lst string[]
--- @return string
local function format_list(lst)
local ret = {} --- @type string[]
for _, v in ipairs(lst) do
ret[#ret + 1] = assert:format({ v, n = 1 })[1]
end
return table.concat(ret, ', ')
end
if os.getenv('NVIM_TEST_PRINT_SYSCALLS') == '1' then
for k_, v_ in pairs(sc) do
(function(k, v)
sc[k] = function(...)
local rets = { v(...) }
io.stderr:write(('%s(%s) = %s\n'):format(k, format_list({ ... }), format_list(rets)))
return unpack(rets)
end
end)(k_, v_)
end
end
local function just_fail(_)
return false
end
say:set('assertion.just_fail.positive', '%s')
say:set('assertion.just_fail.negative', '%s')
assert:register(
'assertion',
'just_fail',
just_fail,
'assertion.just_fail.positive',
'assertion.just_fail.negative'
)
local hook_fnamelen = 30
local hook_sfnamelen = 30
local hook_numlen = 5
local hook_msglen = 1 + 1 + 1 + (1 + hook_fnamelen) + (1 + hook_sfnamelen) + (1 + hook_numlen) + 1
local tracehelp = dedent([[
Trace: either in the format described below or custom debug output starting
with `>`. Latter lines still have the same width in byte.
┌ Trace type: _r_eturn from function , function _c_all, _l_ine executed,
│ _t_ail return, _C_ount (should not actually appear),
│ _s_aved from previous run for reference, _>_ for custom debug
│ output.
│┏ Function type: _L_ua function, _C_ function, _m_ain part of chunk,
│┃ function that did _t_ail call.
│┃┌ Function name type: _g_lobal, _l_ocal, _m_ethod, _f_ield, _u_pvalue,
│┃│ space for unknown.
│┃│ ┏ Source file name ┌ Function name ┏ Line
│┃│ ┃ (trunc to 30 bytes, no .lua) │ (truncated to last 30 bytes) ┃ number
CWN SSSSSSSSSSSSSSSSSSSSSSSSSSSSSS:FFFFFFFFFFFFFFFFFFFFFFFFFFFFFF:LLLLL\n
]])
local function child_sethook(wr)
local trace_level_str = os.getenv('NVIM_TEST_TRACE_LEVEL')
local trace_level = 0
if trace_level_str and trace_level_str ~= '' then
--- @type number
trace_level = assert(tonumber(trace_level_str))
end
if trace_level <= 0 then
return
end
local trace_only_c = trace_level <= 1
--- @type debuginfo?, string?, integer
local prev_info, prev_reason, prev_lnum
--- @param reason string
--- @param lnum integer
--- @param use_prev boolean
local function hook(reason, lnum, use_prev)
local info = nil --- @type debuginfo?
if use_prev then
info = prev_info
elseif reason ~= 'tail return' then -- tail return
info = debug.getinfo(2, 'nSl')
end
if trace_only_c and (not info or info.what ~= 'C') and not use_prev then
--- @cast info -nil
if info.source:sub(-9) == '_spec.lua' then
prev_info = info
prev_reason = 'saved'
prev_lnum = lnum
end
return
end
if trace_only_c and not use_prev and prev_reason then
hook(prev_reason, prev_lnum, true)
prev_reason = nil
end
local whatchar = ' '
local namewhatchar = ' '
local funcname = ''
local source = ''
local msgchar = reason:sub(1, 1)
if reason == 'count' then
msgchar = 'C'
end
if info then
funcname = (info.name or ''):sub(1, hook_fnamelen)
whatchar = info.what:sub(1, 1)
namewhatchar = info.namewhat:sub(1, 1)
if namewhatchar == '' then
namewhatchar = ' '
end
source = info.source
if source:sub(1, 1) == '@' then
if source:sub(-4, -1) == '.lua' then
source = source:sub(1, -5)
end
source = source:sub(-hook_sfnamelen, -1)
end
lnum = lnum or info.currentline
end
-- assert(-1 <= lnum and lnum <= 99999)
local lnum_s = lnum == -1 and 'nknwn' or ('%u'):format(lnum)
--- @type string
local msg = ( -- lua does not support %*
''
.. msgchar
.. whatchar
.. namewhatchar
.. ' '
.. source
.. (' '):rep(hook_sfnamelen - #source)
.. ':'
.. funcname
.. (' '):rep(hook_fnamelen - #funcname)
.. ':'
.. ('0'):rep(hook_numlen - #lnum_s)
.. lnum_s
.. '\n'
)
-- eq(hook_msglen, #msg)
sc.write(wr, msg)
end
debug.sethook(hook, 'crl')
end
local trace_end_msg = ('E%s\n'):format((' '):rep(hook_msglen - 2))
--- @type function
local _debug_log
local debug_log = only_separate(function(...)
return _debug_log(...)
end)
local function itp_child(wr, func)
--- @param s string
_debug_log = function(s)
s = s:sub(1, hook_msglen - 2)
sc.write(wr, '>' .. s .. (' '):rep(hook_msglen - 2 - #s) .. '\n')
end
local status, result = pcall(init)
if status then
collectgarbage('stop')
child_sethook(wr)
status, result = pcall(func)
debug.sethook()
end
sc.write(wr, trace_end_msg)
if not status then
local emsg = tostring(result)
if #emsg > 99999 then
emsg = emsg:sub(1, 99999)
end
sc.write(wr, ('-\n%05u\n%s'):format(#emsg, emsg))
deinit()
else
sc.write(wr, '+\n')
deinit()
end
collectgarbage('restart')
collectgarbage()
sc.write(wr, '$\n')
sc.close(wr)
sc.exit(status and 0 or 1)
end
local function check_child_err(rd)
local trace = {} --- @type string[]
local did_traceline = false
local maxtrace = tonumber(os.getenv('NVIM_TEST_MAXTRACE')) or 1024
while true do
local traceline = sc.read(rd, hook_msglen)
if #traceline ~= hook_msglen then
if #traceline == 0 then
break
else
trace[#trace + 1] = 'Partial read: <' .. trace .. '>\n'
end
end
if traceline == trace_end_msg then
did_traceline = true
break
end
trace[#trace + 1] = traceline
if #trace > maxtrace then
table.remove(trace, 1)
end
end
local res = sc.read(rd, 2)
if #res == 2 then
local err = ''
if res ~= '+\n' then
eq('-\n', res)
local len_s = sc.read(rd, 5)
local len = tonumber(len_s)
neq(0, len)
if os.getenv('NVIM_TEST_TRACE_ON_ERROR') == '1' and #trace ~= 0 then
--- @type string
err = '\nTest failed, trace:\n' .. tracehelp
for _, traceline in ipairs(trace) do
--- @type string
err = err .. traceline
end
end
--- @type string
err = err .. sc.read(rd, len + 1)
end
local eres = sc.read(rd, 2)
if eres ~= '$\n' then
if #trace == 0 then
err = '\nTest crashed, no trace available (check NVIM_TEST_TRACE_LEVEL)\n'
else
err = '\nTest crashed, trace:\n' .. tracehelp
for i = 1, #trace do
err = err .. trace[i]
end
end
if not did_traceline then
--- @type string
err = err .. '\nNo end of trace occurred'
end
local cc_err, cc_emsg = pcall(check_cores, paths.test_luajit_prg, true)
if not cc_err then
--- @type string
err = err .. '\ncheck_cores failed: ' .. cc_emsg
end
end
if err ~= '' then
assert.just_fail(err)
end
end
end
local function itp_parent(rd, pid, allow_failure, location)
local ok, emsg = pcall(check_child_err, rd)
local status = sc.wait(pid)
sc.close(rd)
if not ok then
if allow_failure then
io.stderr:write('Errorred out (' .. status .. '):\n' .. tostring(emsg) .. '\n')
os.execute([[
sh -c "source ci/common/test.sh
check_core_dumps --delete \"]] .. paths.test_luajit_prg .. [[\""]])
else
error(tostring(emsg) .. '\nexit code: ' .. status)
end
elseif status ~= 0 then
if not allow_failure then
error('child process errored out with status ' .. status .. '!\n\n' .. location)
end
end
end
local function gen_itp(it)
child_calls_mod = {}
child_calls_mod_once = {}
child_cleanups_mod_once = {}
preprocess_cache_mod = map(function(v)
return v
end, preprocess_cache_init)
previous_defines_mod = previous_defines_init
cdefs_mod = cdefs_init:copy()
local function itp(name, func, allow_failure)
if allow_failure and os.getenv('NVIM_TEST_RUN_FAILING_TESTS') ~= '1' then
-- FIXME Fix tests with this true
return
end
-- Pre-emptively calculating error location, wasteful, ugh!
-- But the way this code messes around with busted implies the real location is strictly
-- not available in the parent when an actual error occurs. so we have to do this here.
local location = debug.traceback()
it(name, function()
local rd, wr = sc.pipe()
child_pid = sc.fork()
if child_pid == 0 then
sc.close(rd)
itp_child(wr, func)
else
sc.close(wr)
local saved_child_pid = child_pid
child_pid = nil
itp_parent(rd, saved_child_pid, allow_failure, location)
end
end)
end
return itp
end
local function cppimport(path)
return cimport(paths.test_source_path .. '/test/includes/pre/' .. path)
end
cimport(
'./src/nvim/types_defs.h',
'./src/nvim/main.h',
'./src/nvim/os/time.h',
'./src/nvim/os/fs.h'
)
local function conv_enum(etab, eval)
local n = tonumber(eval)
return etab[n] or n
end
local function array_size(arr)
return ffi.sizeof(arr) / ffi.sizeof(arr[0])
end
local function kvi_size(kvi)
return array_size(kvi.init_array)
end
local function kvi_init(kvi)
kvi.capacity = kvi_size(kvi)
kvi.items = kvi.init_array
return kvi
end
local function kvi_destroy(kvi)
if kvi.items ~= kvi.init_array then
lib.xfree(kvi.items)
end
end
local function kvi_new(ct)
return kvi_init(ffi.new(ct))
end
local function make_enum_conv_tab(m, values, skip_pref, set_cb)
child_call_once(function()
local ret = {}
for _, v in ipairs(values) do
local str_v = v
if v:sub(1, #skip_pref) == skip_pref then
str_v = v:sub(#skip_pref + 1)
end
ret[tonumber(m[v])] = str_v
end
set_cb(ret)
end)
end
local function ptr2addr(ptr)
return tonumber(ffi.cast('intptr_t', ffi.cast('void *', ptr)))
end
local s = ffi.new('char[64]', { 0 })
local function ptr2key(ptr)
ffi.C.snprintf(s, ffi.sizeof(s), '%p', ffi.cast('void *', ptr))
return ffi.string(s)
end
local function is_asan()
cimport('./src/nvim/version.h')
local status, res = pcall(function()
return lib.version_cflags
end)
if status then
return ffi.string(res):match('-fsanitize=[a-z,]*address')
else
return false
end
end
--- @class test.unit.testutil.module
local M = {
cimport = cimport,
cppimport = cppimport,
internalize = internalize,
ffi = ffi,
lib = lib,
cstr = cstr,
to_cstr = to_cstr,
NULL = ffi.cast('void*', 0),
OK = 1,
FAIL = 0,
alloc_log_new = alloc_log_new,
gen_itp = gen_itp,
only_separate = only_separate,
child_call_once = child_call_once,
child_cleanup_once = child_cleanup_once,
sc = sc,
conv_enum = conv_enum,
array_size = array_size,
kvi_destroy = kvi_destroy,
kvi_size = kvi_size,
kvi_init = kvi_init,
kvi_new = kvi_new,
make_enum_conv_tab = make_enum_conv_tab,
ptr2addr = ptr2addr,
ptr2key = ptr2key,
debug_log = debug_log,
is_asan = is_asan,
}
--- @class test.unit.testutil: test.unit.testutil.module, test.testutil
M = vim.tbl_extend('error', M, t_global)
return M