remove python 2.7.x specific code

IPython/utils/openpy.py

@@ -9,117 +9,11 b' import io'
 from io import TextIOWrapper, BytesIO
 import os.path
 import re
-
+from tokenize import open, detect_encoding
 
 cookie_re = re.compile(r"coding[:=]\s*([-\w.]+)", re.UNICODE)
 cookie_comment_re = re.compile(r"^\s*#.*coding[:=]\s*([-\w.]+)", re.UNICODE)
 
-try:
-    # Available in Python 3
-    from tokenize import detect_encoding
-except ImportError:
-    from codecs import lookup, BOM_UTF8
-    
-    # Copied from Python 3.2 tokenize
-    def _get_normal_name(orig_enc):
-        """Imitates get_normal_name in tokenizer.c."""
-        # Only care about the first 12 characters.
-        enc = orig_enc[:12].lower().replace("_", "-")
-        if enc == "utf-8" or enc.startswith("utf-8-"):
-            return "utf-8"
-        if enc in ("latin-1", "iso-8859-1", "iso-latin-1") or \
-           enc.startswith(("latin-1-", "iso-8859-1-", "iso-latin-1-")):
-            return "iso-8859-1"
-        return orig_enc
-    
-    # Copied from Python 3.2 tokenize
-    def detect_encoding(readline):
-        """
-        The detect_encoding() function is used to detect the encoding that should
-        be used to decode a Python source file.  It requires one argment, readline,
-        in the same way as the tokenize() generator.
-
-        It will call readline a maximum of twice, and return the encoding used
-        (as a string) and a list of any lines (left as bytes) it has read in.
-
-        It detects the encoding from the presence of a utf-8 bom or an encoding
-        cookie as specified in pep-0263.  If both a bom and a cookie are present,
-        but disagree, a SyntaxError will be raised.  If the encoding cookie is an
-        invalid charset, raise a SyntaxError.  Note that if a utf-8 bom is found,
-        'utf-8-sig' is returned.
-
-        If no encoding is specified, then the default of 'utf-8' will be returned.
-        """
-        bom_found = False
-        encoding = None
-        default = 'utf-8'
-        def read_or_stop():
-            try:
-                return readline()
-            except StopIteration:
-                return b''
-
-        def find_cookie(line):
-            try:
-                line_string = line.decode('ascii')
-            except UnicodeDecodeError:
-                return None
-
-            matches = cookie_re.findall(line_string)
-            if not matches:
-                return None
-            encoding = _get_normal_name(matches[0])
-            try:
-                codec = lookup(encoding)
-            except LookupError:
-                # This behaviour mimics the Python interpreter
-                raise SyntaxError("unknown encoding: " + encoding)
-
-            if bom_found:
-                if codec.name != 'utf-8':
-                    # This behaviour mimics the Python interpreter
-                    raise SyntaxError('encoding problem: utf-8')
-                encoding += '-sig'
-            return encoding
-
-        first = read_or_stop()
-        if first.startswith(BOM_UTF8):
-            bom_found = True
-            first = first[3:]
-            default = 'utf-8-sig'
-        if not first:
-            return default, []
-
-        encoding = find_cookie(first)
-        if encoding:
-            return encoding, [first]
-
-        second = read_or_stop()
-        if not second:
-            return default, [first]
-
-        encoding = find_cookie(second)
-        if encoding:
-            return encoding, [first, second]
-
-        return default, [first, second]
-
-try:
-    # Available in Python 3.2 and above.
-    from tokenize import open
-except ImportError:
-    # Copied from Python 3.2 tokenize
-    def open(filename):
-        """Open a file in read only mode using the encoding detected by
-        detect_encoding().
-        """
-        buffer = io.open(filename, 'rb')   # Tweaked to use io.open for Python 2
-        encoding, lines = detect_encoding(buffer.readline)
-        buffer.seek(0)
-        text = TextIOWrapper(buffer, encoding, line_buffering=True)
-        text.mode = 'r'
-        return text   
-
 def source_to_unicode(txt, errors='replace', skip_encoding_cookie=True):
     """Converts a bytes string with python source code to unicode.
 
@@ -206,10 +100,7 b" def read_py_url(url, errors='replace', skip_encoding_cookie=True):"
     A unicode string containing the contents of the file.
     """
     # Deferred import for faster start
-    try:
-        from urllib.request import urlopen # Py 3
-    except ImportError:
-        from urllib import urlopen
+    from urllib.request import urlopen 
     response = urlopen(url)
     buffer = io.BytesIO(response.read())
     return source_to_unicode(buffer, errors, skip_encoding_cookie)
@@ -224,24 +115,8 b' def _list_readline(x):'
     return readline
 
 # Code for going between .py files and cached .pyc files ----------------------
-
-try:    # Python 3.2, see PEP 3147
     try: 
         from importlib.util import source_from_cache, cache_from_source
     except ImportError :
         ## deprecated since 3.4
         from imp import source_from_cache, cache_from_source
-except ImportError:
-    # Python <= 3.1: .pyc files go next to .py
-    def source_from_cache(path):
-        basename, ext = os.path.splitext(path)
-        if ext not in ('.pyc', '.pyo'):
-            raise ValueError('Not a cached Python file extension', ext)
-        # Should we look for .pyw files?
-        return basename + '.py'
-    
-    def cache_from_source(path, debug_override=None):
-        if debug_override is None:
-            debug_override = __debug__
-        basename, ext = os.path.splitext(path)
-        return basename + '.pyc' if debug_override else '.pyo'