Hi, Sergey!

<snipped>

+-- OOM in the error handler.
+coroutine.wrap(function()
+  local function errmem() local _ = {} end
+  allocinject.enable_null_alloc()
+  local st, msg = xpcall(error, errmem)
+  allocinject.disable()
+test:ok(not st, 'OOM incorrect status')
+  -- Prevent preallocated error message.
+test:ok(msg:match('error in ' .. 'error handling'),
+          'OOM incorrect errmsg: ' .. msg)
+end)()
+
+-- STKOV in the error handler.

Why abbreviation is used? May be "stack overflow"? Feel free to ignore.

This is done to be consistent witht the OOM abbreviation above.
If you don't insist, I would leave them as is.

+coroutine.wrap(function()
+  local function stkov() stkov() end
+  local st, msg = xpcall(error, stkov)
+test:ok(not st, 'STKOV incorrect status')
+  -- Prevent preallocated error message.
+test:ok(msg:match('error in ' .. 'error handling'),
+          'STKOV incorrect errmsg: ' .. msg)
+end)()
+
+test:done(true)

<snipped>