test: replace tostring(error) with error.message for box.errors

Currently, error message assertions convert `box.error` to string using
`tostring`. `box.error`'s `__tostring` metamethod is currently equivalent
to the `message` field of `box.error`. In scope of tarantool#9105, we are going to
increase the verbosity of `box.error` `__tostring` metamethod, and it will
no longer be convenient for testing the error message. Let's replace
`tostring(error)` usage with `error.message` to retain the old behaviour.

See also tarantool/luatest@xxx (WIP tarantool/luatest#355).

Needed for tarantool#9105

NO_CHANGELOG=<tests change>
NO_DOC=<tests change>

test/app-luatest/fiber_slice_test.lua

@@ -32,7 +32,7 @@ g.test_fiber_slice = function()
         overhead = clock.monotonic() - overhead
         local start_time = clock.monotonic()
         local _, err = fib:join()
-        t.assert_equals(tostring(err), "fiber slice is exceeded")
+        t.assert_equals(err.message, "fiber slice is exceeded")
         local time_elapsed = clock.monotonic() - start_time - overhead
         t.assert_almost_equals(time_elapsed, expected_timeout, delta)
     end

test/app-luatest/http_client_test.lua

@@ -485,7 +485,7 @@ g.test_headers = function(cg)
     local headers = {[hname] = hvalue}
     local ok, err = pcall(http.post, http, url, nil,
                           merge(opts, {headers = headers}))
-    t.assert_equals({ok, tostring(err)}, {false, exp_err},
+    t.assert_equals({ok, err.message}, {false, exp_err},
                     '8193 KiB header: error')
 end
 

test/app-tap/console.test.lua

@@ -133,21 +133,21 @@ box.cfg{
 -- Connect to iproto console (CALL)
 client:write(string.format("require('console').connect('/')\n"))
 -- error: Connection is not established
-test:ok(yaml.decode(client:read(EOL))[1].error:find('not established'),
+test:ok(yaml.decode(client:read(EOL))[1].error.message:find('not established'),
     'remote network error')
 
 client:write(string.format("require('console').connect('%s')\n",
     IPROTO_SOCKET))
 -- error: Execute access is denied for user 'guest' to function 'dostring
-test:ok(yaml.decode(client:read(EOL))[1].error:find('denied'),
+test:ok(yaml.decode(client:read(EOL))[1].error.message:find('denied'),
     'remote access denied')
 
 -- create user
 box.schema.user.create('test', { password = 'pass' })
 client:write(string.format("require('console').connect('test:pass@%s')\n",
     IPROTO_SOCKET))
 -- error: Execute access denied for user 'test' to function 'dostring
-test:ok(yaml.decode(client:read(EOL))[1].error:find('denied'),
+test:ok(yaml.decode(client:read(EOL))[1].error.message:find('denied'),
     'remote access denied')
 
 -- Add permissions to execute for `test`

test/app-tap/gh-5013-fiber-cancel.test.lua

@@ -22,5 +22,5 @@ fiber.yield()
 print(require('yaml').encode(result))
 
 test:ok(result.res == false, 'expected result is false')
-test:ok(tostring(result.err) == 'fiber is cancelled', 'fiber cancellation should be reported')
+test:ok(result.err.message == 'fiber is cancelled', 'fiber cancellation should be reported')
 os.exit(test:check() and 0 or 1)

test/app-tap/logger.test.lua

@@ -7,7 +7,7 @@ test:plan(119)
 
 local function test_invalid_cfg(cfg_method, cfg, name, expected)
     local _, err = pcall(cfg_method, cfg)
-    test:ok(tostring(err):find(expected) ~= nil, name)
+    test:ok(err.message:find(expected) ~= nil, name)
 end
 
 local function test_allowed_types(cfg_method, cfg, name, allowed_types)
@@ -205,11 +205,11 @@ test_invalid_cfg(box.cfg, {log_nonblock = true},
 -- Test invalid values for setters
 
 _, err = pcall(log.log_format, {})
-test:ok(tostring(err):find('should be of type string') ~= nil,
+test:ok(err.message:find('should be of type string') ~= nil,
         "invalid format setter value type")
 
 _, err = pcall(log.level, {})
-test:ok(tostring(err):find('should be one of types number, string') ~= nil,
+test:ok(err.message:find('should be one of types number, string') ~= nil,
         "invalid format setter value type")
 
 -- Change format and levels.

test/app-tap/popen.test.lua

@@ -96,7 +96,7 @@ local function test_trivial_echo_output(test)
     -- Sending a signal using a closed handle gives an error.
     local exp_err = 'popen: attempt to operate on a closed handle'
     local ok, err = pcall(ph.signal, ph, popen.signal.SIGTERM)
-    test:is_deeply({ok, err.type, tostring(err)},
+    test:is_deeply({ok, err.type, err.message},
                    {false, 'IllegalParams', exp_err},
                    'signal() on closed handle gives an error')
 end
@@ -247,7 +247,7 @@ local function test_read_timeout(test)
     -- Read and get a timeout error.
     local exp_err = 'timed out'
     local res, err = ph:read({timeout = 0.1})
-    test:is_deeply({res, err.type, tostring(err)}, {nil, 'TimedOut', exp_err},
+    test:is_deeply({res, err.type, err.message}, {nil, 'TimedOut', exp_err},
                    'timeout error')
 
     -- Write and read after the timeout error.

test/app-tap/uri.test.lua

@@ -90,10 +90,10 @@ local function test_parse(test)
     expected_errmsg = "Incorrect URI: expected host:service or /unix.socket"
     u, error = uri.parse("")
     test:isnil(u, "invalid uri", u)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     u, error = uri.parse("://")
     test:isnil(u, "invalid uri", u)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
 end
 
 local function test_format(test)
@@ -245,13 +245,13 @@ local function test_parse_uri_query_params(test)
     expected_errmsg = "Default URI parameters are not allowed for single URI"
     u, error = uri.parse({ "/tmp/unix.sock", default_params = {q = "v"} })
     test:isnil(u, "invalid uri", u)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     -- Multiple URIs is not allowed in `parse` method,
     -- use `parse_many` instead.
     expected_errmsg = "Incorrect URI: expected host:service or /unix.socket"
     u, error = uri.parse({ "/tmp/unix.sock, /tmp/unix.sock"})
     test:isnil(u, "invalid uri", u)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
 end
 
 local function test_parse_uri_set_with_query_params(test)
@@ -314,24 +314,24 @@ local function test_parse_uri_set_with_query_params(test)
     expected_errmsg = "Incorrect URI: expected host:service or /unix.socket"
     uri_set , error= uri.parse_many("/tmp/unix.sock,,/tmp/unix.sock")
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     uri_set, error = uri.parse_many("/tmp/unix.sock, ,/tmp/unix.sock")
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     uri_set, error = uri.parse_many("/tmp/unix.sock,, /tmp/unix.sock")
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     uri_set, error = uri.parse_many("/tmp/unix.sock ,,/tmp/unix.sock")
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
 
 
     -- Check that we can't parse string with multiple URIs,
     -- using old method.
     expected_errmsg = "Incorrect URI: expected host:service or /unix.socket"
     local u, error = uri.parse("/tmp/unix.sock, /tmp/unix.sock")
     test:isnil(u, "invalid uri", u)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
 end
 
 local function test_parse_uri_set_from_lua_table(test)
@@ -575,75 +575,75 @@ local function test_parse_invalid_uri_set_from_lua_table(test)
     expected_errmsg = "Incorrect type for URI: should be string, number or table"
     uri_set, error = uri.parse_many(function() end)
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     -- Invalid type of value for numerical key
     expected_errmsg = "Incorrect type for URI: should be string, number or table"
     uri_set, error = uri.parse_many({"/tmp/unix.sock", function() end})
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     -- Invalid type of value for string keys
     expected_errmsg = "Invalid URI table: expected " ..
                       "{uri = string, params = table}" .. " or " ..
                       "{string, params = table}"
     uri_set, error = uri.parse_many({"/tmp/unix.sock", uri = function() end})
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     expected_errmsg = "Incorrect type for URI parameters: should be a table"
     uri_set, error = uri.parse_many({"/tmp/unix.sock", params = function() end})
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     expected_errmsg = "Incorrect type for URI parameters: should be a table"
     uri_set, error = uri.parse_many({"/tmp/unix.sock", params = ""})
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     expected_errmsg = "Default URI parameters are not allowed for single URI"
     uri_set, error = uri.parse_many({"/tmp/unix.sock", default_params = ""})
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     expected_errmsg = "Default URI parameters are not allowed for single URI"
     uri_set, error = uri.parse_many({"/tmp/unix.sock", default_params = ""})
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
 
     -- Mix "uri=" and numerical keys is banned
     expected_errmsg = "Invalid URI table: expected " ..
                       "{uri = string, params = table}" .. " or " ..
                       "{string, params = table}"
     uri_set, error = uri.parse_many({"/tmp/unix.sock", uri = "/tmp/unix.sock"})
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     -- Several URIs in one string is allowed only when the
     -- passed as a single string.
     expected_errmsg = "Incorrect URI: expected host:service or /unix.socket"
     uri_set, error = uri.parse_many({"/tmp/unix.sock, /tmp/unix.sock"})
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     -- "params" table is allowed only for single URI
     expected_errmsg = "URI parameters are not allowed for multiple URIs"
     uri_set, error = uri.parse_many({
         "/tmp/unix.sock", "/tmp/unix.sock",
         params = {q1 = "v1"}
     })
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     -- "params" table is not allowed with nested tables
     expected_errmsg = "URI parameters are not allowed for multiple URIs"
     uri_set, error = uri.parse_many({
         {"/tmp/unix.sock"},
         params = {q1 = "v1"}
     })
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     -- "default_params" table is not allowed in nested URI tables
     expected_errmsg = "Default URI parameters are not allowed for single URI"
     uri_set, error = uri.parse_many({{"/tmp/unix.sock", default_params = {}}})
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     -- "default_params" table is not allowed for single URI
     expected_errmsg = "Default URI parameters are not allowed for single URI"
     uri_set, error = uri.parse_many({"/tmp/unix.sock", default_params = {}})
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     -- Only one URI is allowed in nested tables
     expected_errmsg = "Invalid URI table: expected " ..
                       "{uri = string, params = table}" .. " or " ..
@@ -653,7 +653,7 @@ local function test_parse_invalid_uri_set_from_lua_table(test)
         default_params = {q = "v"}
     })
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     -- Nested URI tables is not allowed in nested tables
     expected_errmsg = "Invalid URI table: expected "..
                       "{uri = string, params = table}" .. " or " ..
@@ -662,7 +662,7 @@ local function test_parse_invalid_uri_set_from_lua_table(test)
         {"/tmp/unix.sock", {}}
     })
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     -- Nested URI table without URI is now allowed
     expected_errmsg = "Invalid URI table: expected "..
                       "{uri = string, params = table}" .. " or " ..
@@ -672,7 +672,7 @@ local function test_parse_invalid_uri_set_from_lua_table(test)
         { params = {q = "v"} }
     })
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     -- Only string key types are allowed in "params" and
     -- "default_params" table
     expected_errmsg = "Incorrect type for URI parameter name: " ..
@@ -682,14 +682,14 @@ local function test_parse_invalid_uri_set_from_lua_table(test)
         params = {"v"},
     })
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     expected_errmsg = "Default URI parameters are not allowed for single URI"
     uri_set, error = uri.parse_many({
         "/tmp/unix.sock",
         default_params = {"v"},
     })
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     -- Invalid type of values in "params" and
     -- "default_params" table
     expected_errmsg = "Incorrect type for URI parameter value: " ..
@@ -699,53 +699,53 @@ local function test_parse_invalid_uri_set_from_lua_table(test)
         params = {q = function() end},
     })
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     expected_errmsg = "Default URI parameters are not allowed for single URI"
     uri_set, error = uri.parse_many({
         "/tmp/unix.sock",
         default_params = {q = function() end},
     })
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     expected_errmsg = "Incorrect type for URI parameter value: "..
                       "should be string or number"
     uri_set, error = uri.parse_many({
         "/tmp/unix.sock",
         params = {q = {function() end}},
     })
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     expected_errmsg = "Default URI parameters are not allowed for single URI"
     uri_set, error = uri.parse_many({
         "/tmp/unix.sock",
         default_params = {q = {function() end}},
     })
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     -- Invalid uri string in URIs table
     expected_errmsg = "Incorrect URI: expected host:service or /unix.socket"
     uri_set, error = uri.parse_many({
         "/tmp/unix.sock",
         "://"
     })
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     -- Invalid uri in nested URI table
     expected_errmsg = "Incorrect URI: expected host:service or /unix.socket"
     uri_set, error = uri.parse_many({
         "/tmp/unix.sock",
         {"://"}
     })
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
     -- Same as previous but with "uri=" syntax
     expected_errmsg = "Incorrect URI: expected host:service or /unix.socket"
     uri_set, error = uri.parse_many({
         "/tmp/unix.sock",
         {uri = "://"}
     })
     test:isnil(uri_set, "invalid uri", uri_set)
-    test:is(tostring(error), expected_errmsg, "error message")
+    test:is(error.message, expected_errmsg, "error message")
 end
 
 local test = tap.test("uri")

test/box-luatest/gh_6085_limit_iteration_in_space_test.lua

@@ -33,7 +33,7 @@ g.test_limit_iteration = function()
             local fib = fiber.new(fiber_f)
             fib:set_joinable(true)
             local _, err = fib:join()
-            t.assert_equals(tostring(err), "fiber slice is exceeded")
+            t.assert_equals(err.message, "fiber slice is exceeded")
         end
 
         fiber.set_max_slice(0.2)
@@ -92,7 +92,7 @@ g.test_limit_on_sigurg = function()
     os.execute('kill -URG ' .. tonumber(pid))
     local _, err = future:wait_result(1.5)
     local end_time = clock.monotonic()
-    t.assert_equals(tostring(err), "fiber slice is exceeded")
+    t.assert_equals(err.message, "fiber slice is exceeded")
     -- Must end before slice is over.
     t.assert(end_time - start_time < 3)
 end

test/box-luatest/gh_7939_fix_meamleak_on_tuple_encode_test.lua

@@ -176,12 +176,12 @@ g.test_misc_region_leaks = function(cg)
             }
         ');]])
         t.assert_equals(ret, nil)
-        t.assert_equals(tostring(err), errmsg)
+        t.assert_equals(err.message, errmsg)
         t.assert_equals(before, mem_used())
 
         ret, err = box.execute('SELECT ?;', {{trouble}})
         t.assert_equals(ret, nil)
-        t.assert_equals(tostring(err), errmsg)
+        t.assert_equals(err.message, errmsg)
         t.assert_equals(before, mem_used())
     end)
 end

test/box-luatest/gh_8802_box_session_push_deprecation_test.lua

@@ -65,7 +65,7 @@ g.test = function(cg)
         t.assert_equals(ok, compat.box_session_push_deprecation:is_old(),
                         'box.session.push status')
         if not ok then
-            t.assert_equals(tostring(err), 'box.session.push is deprecated',
+            t.assert_equals(err.message, 'box.session.push is deprecated',
                             'box.session.push error')
         end
     end)
@@ -84,7 +84,7 @@ g.test = function(cg)
         t.assert_equals(ok, compat.box_session_push_deprecation:is_old(),
                         'box.session.push status')
         if not ok then
-            t.assert_equals(tostring(err), 'box.session.push is deprecated',
+            t.assert_equals(err.message, 'box.session.push is deprecated',
                             'box.session.push error')
         end
     end)