error: introduce is_timeout

It's needed to check, whether the error was a timeout or not in the
following commit. Let's move this function from vtest to error module.

Needed for #426

NO_DOC=internal

test/luatest_helpers/vtest.lua

@@ -65,17 +65,6 @@ local function replicaset_name_to_uuid(name)
     return name_to_uuid(replicaset_name_to_uuid_map, name)
 end
 
---
--- Timeout error can be a ClientError with ER_TIMEOUT code or a TimedOut error
--- which is ER_SYSTEM. They also have different messages. Same public APIs can
--- return both errors depending on core version and/or error cause. This func
--- helps not to care.
---
-local function error_is_timeout(err)
-    return err.code == box.error.TIMEOUT or (err.code == box.error.PROC_LUA and
-           err.message == 'Timeout exceeded') or err.type == 'TimedOut'
-end
-
 local function clear_test_cfg_options(cfg)
     cfg.test_user_grant_range = nil
 end
@@ -848,7 +837,6 @@ end
 local vardir = fio.abspath(os.getenv('VARDIR'))
 
 return {
-    error_is_timeout = error_is_timeout,
     config_new = config_new,
     cluster_new = cluster_new,
     cluster_cfg = cluster_cfg,

test/replicaset-luatest/replicaset_3_test.lua

@@ -2,6 +2,7 @@ local fiber = require('fiber')
 local t = require('luatest')
 local vreplicaset = require('vshard.replicaset')
 local vtest = require('test.luatest_helpers.vtest')
+local verror = require('vshard.error')
 
 local small_timeout_opts = {timeout = 0.05}
 local timeout_opts = {timeout = vtest.wait_timeout}
@@ -176,7 +177,7 @@ test_group.test_map_call = function(g)
     end, {uuid_c})
     res, err = rs:map_call('test_sleep_c', {}, small_timeout_opts)
     t.assert_not_equals(err, nil)
-    t.assert(vtest.error_is_timeout(err))
+    t.assert(verror.is_timeout(err))
     t.assert_equals(res, nil)
     res = vtest.cluster_exec_each(g, function()
         _G.test_sleep_do = false

test/storage-luatest/storage_1_1_1_test.lua

@@ -74,7 +74,7 @@ test_group.test_manual_bucket_send_doubled_buckets = function(g)
     local bid = g.replica_1_a:exec(function(uuid)
         local bid = _G.get_first_bucket()
         local ok, err = ivshard.storage.bucket_send(bid, uuid)
-        ilt.assert(ivtest.error_is_timeout(err))
+        ilt.assert(iverror.is_timeout(err))
         ilt.assert_not(ok, 'bucket_send not ok')
         return bid
     end, {uuid_2})

test/unit-luatest/util_test.lua

@@ -1,8 +1,8 @@
 local t = require('luatest')
 local luuid = require('uuid')
 local server = require('test.luatest_helpers.server')
-local vtest = require('test.luatest_helpers.vtest')
 local vutil = require('vshard.util')
+local verror = require('vshard.error')
 local net = require('net.box')
 
 local test_group = t.group('util')
@@ -252,11 +252,11 @@ test_group.test_future_wait_timeout = function(g)
 
     -- Default timeout error
     local _, err = vutil.future_wait(f, 1e-6)
-    t.assert_equals(vtest.error_is_timeout(err), true)
+    t.assert_equals(verror.is_timeout(err), true)
 
     -- Negative timeout should return timeout error too
     _, err = vutil.future_wait(f, -1)
-    t.assert_equals(vtest.error_is_timeout(err), true)
+    t.assert_equals(verror.is_timeout(err), true)
 
     stop_sleep()
     -- Everything is all right, wait for result

vshard/error.lua

@@ -317,6 +317,17 @@ local function make_timeout()
     return make_error(box.error.new(box.error.TIMEOUT))
 end
 
+--
+-- Timeout error can be a ClientError with ER_TIMEOUT code or a TimedOut error
+-- which is ER_SYSTEM. They also have different messages. Same public APIs can
+-- return both errors depending on core version and/or error cause. This func
+-- helps not to care.
+--
+local function error_is_timeout(err)
+    return err.code == box.error.TIMEOUT or (err.code == box.error.PROC_LUA and
+           err.message == 'Timeout exceeded') or err.type == 'TimedOut'
+end
+
 return {
     code = error_code,
     box = box_error,
@@ -325,4 +336,5 @@ return {
     from_string = from_string,
     alert = make_alert,
     timeout = make_timeout,
+    is_timeout = error_is_timeout,
 }