Helpers.GetDefaultEncoding is added

This function is equal to os_ops.get_default_encoding and is used in:
 - Helpers.PrepareProcessInput
 - RaiseError._TranslateDataIntoString__FromBinary

Author: dmitry-lipetsk

testgres/operations/helpers.py

@@ -1,11 +1,48 @@
+import locale
+
+
 class Helpers:
+    def _make_get_default_encoding_func():
+        # locale.getencoding is added in Python 3.11
+        if hasattr(locale, 'getencoding'):
+            return locale.getencoding
+
+        # It must exist
+        return locale.getpreferredencoding
+
+    # Prepared pointer on function to get a name of system codepage
+    _get_default_encoding_func = _make_get_default_encoding_func()
+
+    def GetDefaultEncoding():
+        #
+        #   Original idea/source was:
+        #
+        #   def os_ops.get_default_encoding():
+        #       if not hasattr(locale, 'getencoding'):
+        #       locale.getencoding = locale.getpreferredencoding
+        #       return locale.getencoding() or 'UTF-8'
+        #
+
+        assert __class__._get_default_encoding_func is not None
+
+        r = __class__._get_default_encoding_func()
+
+        if r:
+            assert r is not None
+            assert type(r) == str  # noqa: E721
+            assert r != ""
+            return r
+
+        # Is it an unexpected situation?
+        return 'UTF-8'
+
     def PrepareProcessInput(input, encoding):
         if not input:
             return None
 
         if type(input) == str:  # noqa: E721
             if encoding is None:
-                return input.encode()
+                return input.encode(__class__.GetDefaultEncoding())
 
             assert type(encoding) == str  # noqa: E721
             return input.encode(encoding)

testgres/operations/raise_error.py

@@ -1,4 +1,5 @@
 from ..exceptions import ExecUtilException
+from .helpers import Helpers
 
 
 class RaiseError:
@@ -29,7 +30,7 @@ def _TranslateDataIntoString__FromBinary(data):
         assert type(data) == bytes  # noqa: E721
 
         try:
-            return data.decode('utf-8')
+            return data.decode(Helpers.GetDefaultEncoding())
         except UnicodeDecodeError:
             pass