fixup! Add stricter check for print() vs. tostring() shortcut.

Author: igormunkin

test/tarantool-tests/lj-351-print-tostring-number.test.lua

@@ -0,0 +1,41 @@
+local utils = require('utils')
+
+local cases = {
+  {typename = 'nil', value = 'nil'},
+  {typename = 'boolean', value = 'true'},
+  {typename = 'number', value = '42'},
+  -- FIXME: This test case is disabled, because __tostring
+  -- metamethod isn't checked for string base metatable.
+  -- See also https://github.com/tarantool/tarantool/issues/6746.
+  -- {'string', '"teststr"'},
+  {typename = 'table', value = '{}'},
+  {typename = 'function', value = 'function() end'},
+  {typename = 'userdata', value = 'newproxy()'},
+  {typename = 'thread', value = 'coroutine.create(function() end)'},
+  {typename = 'cdata', value = '1ULL'}
+}
+
+local checks = {}
+
+for i, case in pairs(cases) do
+  checks[i] = {
+    arg = {('"%s"'):format(case.value), case.typename},
+    msg = ('%s'):format(case.typename),
+    res = ('__tostring is reloaded for %s'):format(case.typename),
+    test = 'is',
+  }
+end
+
+utils.selfrun(arg, checks)
+
+----- Test payload. ----------------------------------------------
+
+local test = [[
+  local testvar = %s
+  debug.setmetatable(testvar, {__tostring = function(o)
+    return ('__tostring is reloaded for %s'):format(type(o))
+  end})
+  print(testvar)
+]]
+
+pcall(load(test:format(unpack(arg))))