encoding: remove Python 2 support code

Differential Revision: https://phab.mercurial-scm.org/D12295

mercurial/encoding.py

@@ -46,7 +46,6 b' asciiupper = charencode.asciiupper'
 
 _sysstr = pycompat.sysstr
 
-if pycompat.ispy3:
     unichr = chr
 
 # These unicode characters are ignored by HFS+ (Apple Technote 1150,
@@ -78,10 +77,8 b' def hfsignoreclean(s):'
 
 # encoding.environ is provided read-only, which may not be used to modify
 # the process environment
-_nativeenviron = not pycompat.ispy3 or os.supports_bytes_environ
-if not pycompat.ispy3:
-    environ = os.environ  # re-exports
-elif _nativeenviron:
+_nativeenviron = os.supports_bytes_environ
+if _nativeenviron:
     environ = os.environb  # re-exports
 else:
     # preferred encoding isn't known yet; use utf-8 to avoid unicode error
@@ -98,7 +95,7 b' else:'
 # cp65001 is a Windows variant of utf-8, which isn't supported on Python 2.
 # No idea if it should be rewritten to the canonical name 'utf-8' on Python 3.
 # https://bugs.python.org/issue13216
-if pycompat.iswindows and not pycompat.ispy3:
+if pycompat.iswindows:
     _encodingrewrites[b'cp65001'] = b'utf-8'
 
 try:
@@ -270,21 +267,9 b' def unimethod(bytesfunc):'
 # converter functions between native str and byte string. use these if the
 # character encoding is not aware (e.g. exception message) or is known to
 # be locale dependent (e.g. date formatting.)
-if pycompat.ispy3:
     strtolocal = unitolocal
     strfromlocal = unifromlocal
     strmethod = unimethod
-else:
-
-    def strtolocal(s):
-        # type: (str) -> bytes
-        return s  # pytype: disable=bad-return-type
-
-    def strfromlocal(s):
-        # type: (bytes) -> str
-        return s  # pytype: disable=bad-return-type
-
-    strmethod = pycompat.identity
 
 
 def lower(s):
@@ -344,7 +329,7 b' def upperfallback(s):'
 if not _nativeenviron:
     # now encoding and helper functions are available, recreate the environ
     # dict to be exported to other modules
-    if pycompat.iswindows and pycompat.ispy3:
+    if pycompat.iswindows:
 
         class WindowsEnviron(dict):
             """`os.environ` normalizes environment variables to uppercase on windows"""
@@ -360,7 +345,6 b' if not _nativeenviron:'
 
 DRIVE_RE = re.compile(b'^[a-z]:')
 
-if pycompat.ispy3:
     # os.getcwd() on Python 3 returns string, but it has os.getcwdb() which
     # returns bytes.
     if pycompat.iswindows:
@@ -386,10 +370,9 b' if pycompat.ispy3:'
                 cwd = cwd[0:1].upper() + cwd[1:]
             return cwd
 
+
     else:
         getcwd = os.getcwdb  # re-exports
-else:
-    getcwd = os.getcwd  # re-exports
 
 # How to treat ambiguous-width characters. Set to 'wide' to treat as wide.
 _wide = _sysstr(
@@ -600,10 +583,7 b' def jsonescape(s, paranoid=False):'
 
 # We need to decode/encode U+DCxx codes transparently since invalid UTF-8
 # bytes are mapped to that range.
-if pycompat.ispy3:
     _utf8strict = r'surrogatepass'
-else:
-    _utf8strict = r'strict'
 
 _utf8len = [0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 3, 4]