Prepare for Python2-Python3 straddle.

- Remove PY25 cruft.

- Selectively apply cleanups from 'python-modernize':

  - New exception syntax.
  - Use 'six' to handle module renames.
  - Use 'six' to handle text / binary stuff.

This PR covers most of the work from #66 which falls inside `python`
(rather than the Python code generation stuff in 'src').

1 files changed, 8 insertions, 12 deletions

diff --git a/python/google/protobuf/text_encoding.py b/python/google/protobuf/text_encoding.py
index 2d86a67c..a0728e3c 100644
--- a/python/google/protobuf/text_encoding.py
+++ b/python/google/protobuf/text_encoding.py
@@ -27,16 +27,13 @@
 # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-#PY25 compatible for GAE.
-#
 """Encoding related utilities."""
-
 import re
-import sys  ##PY25
+
+import six
 
 # Lookup table for utf8
-_cescape_utf8_to_str = [chr(i) for i in xrange(0, 256)]
+_cescape_utf8_to_str = [chr(i) for i in range(0, 256)]
 _cescape_utf8_to_str[9] = r'\t'  # optional escape
 _cescape_utf8_to_str[10] = r'\n'  # optional escape
 _cescape_utf8_to_str[13] = r'\r'  # optional escape
@@ -46,9 +43,9 @@ _cescape_utf8_to_str[34] = r'\"'  # necessary escape
 _cescape_utf8_to_str[92] = r'\\'  # necessary escape
 
 # Lookup table for non-utf8, with necessary escapes at (o >= 127 or o < 32)
-_cescape_byte_to_str = ([r'\%03o' % i for i in xrange(0, 32)] +
-                        [chr(i) for i in xrange(32, 127)] +
-                        [r'\%03o' % i for i in xrange(127, 256)])
+_cescape_byte_to_str = ([r'\%03o' % i for i in range(0, 32)] +
+                        [chr(i) for i in range(32, 127)] +
+                        [r'\%03o' % i for i in range(127, 256)])
 _cescape_byte_to_str[9] = r'\t'  # optional escape
 _cescape_byte_to_str[10] = r'\n'  # optional escape
 _cescape_byte_to_str[13] = r'\r'  # optional escape
@@ -75,7 +72,7 @@ def CEscape(text, as_utf8):
   """
   # PY3 hack: make Ord work for str and bytes:
   # //platforms/networking/data uses unicode here, hence basestring.
-  Ord = ord if isinstance(text, basestring) else lambda x: x
+  Ord = ord if isinstance(text, six.string_types) else lambda x: x
   if as_utf8:
     return ''.join(_cescape_utf8_to_str[Ord(c)] for c in text)
   return ''.join(_cescape_byte_to_str[Ord(c)] for c in text)
@@ -100,8 +97,7 @@ def CUnescape(text):
   # allow single-digit hex escapes (like '\xf').
   result = _CUNESCAPE_HEX.sub(ReplaceHex, text)
 
-  if sys.version_info[0] < 3:  ##PY25
-##!PY25  if str is bytes:  # PY2
+  if str is bytes:  # PY2
     return result.decode('string_escape')
   result = ''.join(_cescape_highbit_to_str[ord(c)] for c in result)
   return (result.encode('ascii')  # Make it bytes to allow decode.