bpo-36793: Remove unneeded __str__ definitions. (GH-13081)

Classes that define __str__ the same as __repr__ can
just inherit it from object.

Author: serhiy-storchaka

Doc/whatsnew/3.8.rst

@@ -811,6 +811,13 @@ Changes in Python behavior
   raised when getting the attribute from the type dictionary are no longer
   ignored.  (Contributed by Serhiy Storchaka in :issue:`35459`.)
 
+* Removed ``__str__`` implementations from builtin types :class:`bool`,
+  :class:`int`, :class:`float`, :class:`complex` and few classes from
+  the standard library.  They now inherit ``__str__()`` from :class:`object`.
+  As result, defining the ``__repr__()`` method in the subclass of these
+  classes will affect they string representation.
+  (Contributed by Serhiy Storchaka in :issue:`36793`.)
+
 * On AIX, :attr:`sys.platform` doesn't contain the major version anymore.
   It is always ``'aix'``, instead of ``'aix3'`` .. ``'aix7'``.  Since
   older Python versions include the version number, it is recommended to

Lib/_pydecimal.py

@@ -5631,8 +5631,6 @@ def __init__(self, value=None):
     def __repr__(self):
         return "(%r, %r, %r)" % (self.sign, self.int, self.exp)
 
-    __str__ = __repr__
-
 
 
 def _normalize(op1, op2, prec = 0):

Lib/asyncore.py

@@ -262,8 +262,6 @@ def __repr__(self):
                 status.append(repr(self.addr))
         return '<%s at %#x>' % (' '.join(status), id(self))
 
-    __str__ = __repr__
-
     def add_channel(self, map=None):
         #self.log_info('adding channel %s' % self)
         if map is None:

Lib/doctest.py

@@ -2300,7 +2300,7 @@ def __repr__(self):
         name = self._dt_test.name.split('.')
         return "%s (%s)" % (name[-1], '.'.join(name[:-1]))
 
-    __str__ = __repr__
+    __str__ = object.__str__
 
     def shortDescription(self):
         return "Doctest: " + self._dt_test.name
@@ -2399,7 +2399,6 @@ def id(self):
 
     def __repr__(self):
         return self._dt_test.filename
-    __str__ = __repr__
 
     def format_failure(self, err):
         return ('Failed doctest test for %s\n  File "%s", line 0\n\n%s'

Lib/email/charset.py

@@ -241,11 +241,9 @@ def __init__(self, input_charset=DEFAULT_CHARSET):
         self.output_codec = CODEC_MAP.get(self.output_charset,
                                           self.output_charset)
 
-    def __str__(self):
+    def __repr__(self):
         return self.input_charset.lower()
 
-    __repr__ = __str__
-
     def __eq__(self, other):
         return str(self) == str(other).lower()
 

Lib/http/client.py

@@ -1419,8 +1419,7 @@ def __repr__(self):
             e = ''
         return '%s(%i bytes read%s)' % (self.__class__.__name__,
                                         len(self.partial), e)
-    def __str__(self):
-        return repr(self)
+    __str__ = object.__str__
 
 class ImproperConnectionState(HTTPException):
     pass

Lib/json/encoder.py

@@ -268,7 +268,7 @@ def _make_iterencode(markers, _default, _encoder, _indent, _floatstr,
         list=list,
         str=str,
         tuple=tuple,
-        _intstr=int.__str__,
+        _intstr=int.__repr__,
     ):
 
     if _indent is not None and not isinstance(_indent, str):
@@ -307,7 +307,7 @@ def _iterencode_list(lst, _current_indent_level):
             elif value is False:
                 yield buf + 'false'
             elif isinstance(value, int):
-                # Subclasses of int/float may override __str__, but we still
+                # Subclasses of int/float may override __repr__, but we still
                 # want to encode them as integers/floats in JSON. One example
                 # within the standard library is IntEnum.
                 yield buf + _intstr(value)

Lib/logging/__init__.py

@@ -364,12 +364,10 @@ def __init__(self, name, level, pathname, lineno,
         else:
             self.process = None
 
-    def __str__(self):
+    def __repr__(self):
         return '<LogRecord: %s, %s, %s, %s, "%s">'%(self.name, self.levelno,
             self.pathname, self.lineno, self.msg)
 
-    __repr__ = __str__
-
     def getMessage(self):
         """
         Return the message for this LogRecord.

Lib/sre_constants.py

@@ -59,11 +59,9 @@ def __new__(cls, value, name):
         self.name = name
         return self
 
-    def __str__(self):
+    def __repr__(self):
         return self.name
 
-    __repr__ = __str__
-
 MAXREPEAT = _NamedIntConstant(MAXREPEAT, 'MAXREPEAT')
 
 def _makecodes(names):

Lib/subprocess.py

@@ -203,7 +203,6 @@ def __repr__(self):
             return "%s(%d)" % (self.__class__.__name__, int(self))
 
         __del__ = Close
-        __str__ = __repr__
 else:
     # When select or poll has indicated that the file is writable,
     # we can write up to _PIPE_BUF bytes without risk of blocking.