import cleanups

* moved bytes compat functions from utils to utils.compat
  (bord, bjoin, bjoin_ints, bjoin_elems, ujoin)
* renamed bord -> belem_ord for clarify
* a bunch of to_native_str() always use ascii, and
  have fixed input types (always bytes or always unicode).
  these don't need overhead of to_native_str(), so replaced
  those calls with two new funcs: compat.bascii_to_str() /
  compat.uascii_to_str()
* cleaned up a lot of imports from utils/utils.compat to
  pull from correct module
* simplified the to_string() logic of a bunch of handlers
  to reduce unicode<->byte transitions

7 files changed, 114 insertions, 111 deletions

diff --git a/passlib/utils/__init__.py b/passlib/utils/__init__.py
index 0f53a09..74d53c2 100644
--- a/passlib/utils/__init__.py
+++ b/passlib/utils/__init__.py
@@ -17,7 +17,9 @@ import unicodedata
 from warnings import warn
 #site
 #pkg
-from passlib.utils.compat import irange, PY3, unicode, bytes, u, b, _add_doc
+from passlib.utils.compat import _add_doc, b, bytes, bjoin, bjoin_ints, \
+                                 bjoin_elems, exc_err, irange, imap, PY3, u, \
+                                 ujoin, unicode
 #local
 __all__ = [
     # constants
@@ -33,9 +35,6 @@ __all__ = [
 ##    "relocated_function",
 ##    "memoized_class_property",
 
-    #byte compat aliases
-    'bytes',
-
     # unicode helpers
     'consteq',
     'saslprep',
@@ -245,7 +244,6 @@ def relocated_function(target, msg=None, name=None, deprecated=None, mod=None,
 #=============================================================================
 # unicode helpers
 #=============================================================================
-ujoin = _UEMPTY.join
 
 def consteq(left, right):
     """check two strings/bytes for equality, taking constant time relative
@@ -431,67 +429,9 @@ def saslprep(source, errname="value"):
 
     return data
 
-#==========================================================
+#=============================================================================
 # bytes helpers
-#==========================================================
-
-#helpers for joining / extracting elements
-bjoin = _BEMPTY.join
-
-#def bjoin_elems(elems):
-#    """takes series of bytes elements, returns bytes.
-#
-#    elem should be result of bytes[x].
-#    this is another bytes instance under py2,
-#    but it int under py3.
-#
-#    returns bytes.
-#
-#    this is bytes() constructor under py3,
-#    but b"".join() under py2.
-#    """
-#    if PY3:
-#        return bytes(elems)
-#    else:
-#        return bjoin(elems)
-#
-#for efficiency, don't bother with above wrapper...
-if PY3:
-    bjoin_elems = bytes
-else:
-    bjoin_elems = bjoin
-
-#def bord(elem):
-#    """takes bytes element, returns integer.
-#
-#    elem should be result of bytes[x].
-#    this is another bytes instance under py2,
-#    but it int under py3.
-#
-#    returns int in range(0,256).
-#
-#    this is ord() under py2, and noop under py3.
-#    """
-#    if PY3:
-#        assert isinstance(elem, int)
-#        return elem
-#    else:
-#        assert isinstance(elem, bytes)
-#        return ord(elem)
-#
-#for efficiency, don't bother with above wrapper...
-if PY3:
-    def bord(elem):
-        return elem
-else:
-    bord = ord
-
-if PY3:
-    bjoin_ints = bytes
-else:
-    def bjoin_ints(values):
-        return bjoin(chr(v) for v in values)
-
+#=============================================================================
 if PY3:
     def xor_bytes(left, right):
         return bytes(l ^ r for l, r in zip(left, right))
@@ -525,9 +465,10 @@ def render_bytes(source, *args):
 @deprecated_function(deprecated="1.6", removed="1.8")
 def bytes_to_int(value):
     "decode string of bytes as single big-endian integer"
+    from passlib.utils.compat import belem_ord
     out = 0
     for v in value:
-        out = (out<<8) | bord(v)
+        out = (out<<8) | belem_ord(v)
     return out
 
 @deprecated_function(deprecated="1.6", removed="1.8")
diff --git a/passlib/utils/_blowfish/__init__.py b/passlib/utils/_blowfish/__init__.py
index 41914dd..407b78f 100644
--- a/passlib/utils/_blowfish/__init__.py
+++ b/passlib/utils/_blowfish/__init__.py
@@ -54,9 +54,8 @@ released under the BSD license::
 from itertools import chain
 import struct
 #pkg
-from passlib.utils import Base64Engine, BCRYPT_CHARS, rng, getrandbytes, bytes, bord
-from passlib.utils.compat import b, unicode, u
-from passlib.utils.compat.aliases import BytesIO
+from passlib.utils import Base64Engine, BCRYPT_CHARS, getrandbytes, rng
+from passlib.utils.compat import b, bytes, BytesIO, unicode, u
 from passlib.utils._blowfish.unrolled import BlowfishEngine
 #local
 __all__ = [
diff --git a/passlib/utils/compat.py b/passlib/utils/compat.py
index 5b7750c..26892ea 100644
--- a/passlib/utils/compat.py
+++ b/passlib/utils/compat.py
@@ -12,19 +12,46 @@ PY_MIN_32 = sys.version_info >= (3,2) # py 3.2 or later
 #=============================================================================
 # common imports
 #=============================================================================
+import logging; log = logging.getLogger(__name__)
 if PY3:
     import builtins
 else:
     import __builtin__ as builtins
 
+
+def _add_doc(obj, doc):
+    """add docstring to an object"""
+    obj.__doc__ = doc
+
 #=============================================================================
 # the default exported vars
 #=============================================================================
 __all__ = [
-    "u", "b",
-    "irange", "srange", ##"lrange",
-    "lmap",
-    "iteritems",
+    # python versions
+    'PY2', 'PY3', 'PY_MAX_25', 'PY27', 'PY_MIN_32',
+
+    # io
+    'print_',
+
+    # type detection
+    'is_mapping',
+    'callable',
+    'int_types',
+    'num_types',
+
+    # unicode/bytes types & helpers
+    'u', 'b',
+    'unicode', 'bytes', 'sb_types',
+    'uascii_to_str', 'bascii_to_str',
+    'ujoin', 'bjoin', 'bjoin_ints', 'bjoin_elems', 'belem_ord',
+
+    # iteration helpers
+    'irange', 'trange', #'lrange',
+    'imap', 'lmap',
+    'iteritems', 'itervalues',
+
+    # introspection
+    'exc_err', 'get_method_function', '_add_doc',
 ]
 
 #=============================================================================
@@ -85,7 +112,6 @@ if (3,0) <= sys.version_info < (3,2):
     from collections import Callable
     def callable(obj):
         return isinstance(obj, Callable)
-    __all__.append("callable")
 else:
     callable = builtins.callable
 
@@ -97,36 +123,81 @@ else:
     num_types = (int, long, float)
 
 #=============================================================================
-# unicode / bytes helpers
+# unicode & bytes types
 #=============================================================================
 if PY3:
+    unicode = str
+    bytes = builtins.bytes
+#    string_types = (unicode,)
+
     def u(s):
+        assert isinstance(s, str)
         return s
+
     def b(s):
         assert isinstance(s, str)
         return s.encode("latin-1")
-    unicode = str
-    bytes = builtins.bytes
-    __all__.append("unicode")
-#    string_types = (unicode,)
 
 else:
     def u(s):
+        assert isinstance(s, str)
         return s.decode("unicode_escape")
+
     def b(s):
         assert isinstance(s, str)
         return s
-    if PY_MAX_25:
-        bytes = str
-        __all__.append("bytes")
-    else:
-        bytes = builtins.bytes
-    unicode = builtins.unicode
-#    string_types = (unicode, bytes)
 
 sb_types = (unicode, bytes)
 
-# bytes format
+#=============================================================================
+# unicode & bytes helpers
+#=============================================================================
+# function to join list of unicode strings
+ujoin = u('').join
+
+# function to join list of byte strings
+bjoin = b('').join
+
+if PY3:
+    def uascii_to_str(s):
+        assert isinstance(s, unicode)
+        return s
+
+    def bascii_to_str(s):
+        assert isinstance(s, bytes)
+        return s.decode("ascii")
+
+    bjoin_ints = bjoin_elems = bytes
+
+    def belem_ord(elem):
+        return elem
+
+else:
+    def uascii_to_str(s):
+        assert isinstance(s, unicode)
+        return s.encode("ascii")
+
+    def bascii_to_str(s):
+        assert isinstance(s, bytes)
+        return s
+
+    def bjoin_ints(values):
+        return bjoin(chr(v) for v in values)
+
+    bjoin_elems = bjoin
+
+    belem_ord = ord
+
+_add_doc(uascii_to_str, "helper to convert ascii unicode -> native str")
+_add_doc(bascii_to_str, "helper to convert ascii bytes -> native str")
+
+# bjoin_ints -- function to convert list of ordinal integers to byte string.
+
+# bjoin_elems --  function to convert list of byte elements to byte string;
+#                 i.e. what's returned by ``b('a')[0]``...
+#                 this is b('a') under PY2, but 97 under PY3.
+
+# belem_ord -- function to convert byte element to integer -- a noop under PY3
 
 #=============================================================================
 # iteration helpers
@@ -144,7 +215,7 @@ if PY3:
 
     def lmap(*a, **k):
         return list(map(*a,**k))
-    # imap = map
+    imap = map
 
 else:
     irange = xrange
@@ -152,7 +223,7 @@ else:
     ##lrange = range
 
     lmap = map
-    # from itertools import imap
+    from itertools import imap
 
 if PY3:
     def iteritems(d):
@@ -179,10 +250,6 @@ else:
     def get_method_function(method):
         return method.im_func
 
-def _add_doc(obj, doc):
-    """add docstring to an object"""
-    obj.__doc__ = doc
-
 #=============================================================================
 # input/output
 #=============================================================================
diff --git a/passlib/utils/des.py b/passlib/utils/des.py
index ea01048..67c6d93 100644
--- a/passlib/utils/des.py
+++ b/passlib/utils/des.py
@@ -45,8 +45,7 @@ which has some nice notes on how this all works -
 # core
 import struct
 # pkg
-from passlib.utils import bytes, bord, bjoin_ints
-from passlib.utils.compat import trange, irange
+from passlib.utils.compat import bytes, bjoin_ints, belem_ord, irange, trange
 # local
 __all__ = [
     "expand_des_key",
@@ -589,7 +588,7 @@ def expand_des_key(key):
 
     def iter_bits(source):
         for c in source:
-            v = bord(c)
+            v = belem_ord(c)
             for i in irange(7,-1,-1):
                 yield (v>>i) & 1
 
diff --git a/passlib/utils/handlers.py b/passlib/utils/handlers.py
index 52ab2cc..7643c01 100644
--- a/passlib/utils/handlers.py
+++ b/passlib/utils/handlers.py
@@ -14,11 +14,11 @@ from warnings import warn
 #site
 #libs
 from passlib.registry import get_crypt_handler
-from passlib.utils import to_native_str, bytes, b, consteq, \
-        classproperty, h64, getrandstr, getrandbytes, bjoin_ints, \
-        rng, is_crypt_handler, ALL_BYTE_VALUES, MissingBackendError, \
-        BASE64_CHARS, HASH64_CHARS
-from passlib.utils.compat import unicode, u, irange
+from passlib.utils import is_crypt_handler
+from passlib.utils import classproperty, consteq, getrandstr, getrandbytes,\
+                          BASE64_CHARS, HASH64_CHARS, rng, to_native_str, MissingBackendError
+from passlib.utils.compat import b, bjoin_ints, bytes, irange, u, \
+                                 uascii_to_str, unicode
 #pkg
 #local
 __all__ = [
@@ -136,7 +136,7 @@ def render_mc2(ident, salt, checksum, sep=u("$")):
         hash = u("%s%s%s%s") % (ident, salt, sep, checksum)
     else:
         hash = u("%s%s") % (ident, salt)
-    return to_native_str(hash)
+    return uascii_to_str(hash)
 
 def render_mc3(ident, rounds, salt, checksum, sep=u("$")):
     "format hash using 3-part modular crypt format; inverse of parse_mc3"
@@ -144,7 +144,7 @@ def render_mc3(ident, rounds, salt, checksum, sep=u("$")):
         hash = u("%s%s%s%s%s%s") % (ident, rounds, sep, salt, sep, checksum)
     else:
         hash = u("%s%s%s%s") % (ident, rounds, sep, salt)
-    return to_native_str(hash)
+    return uascii_to_str(hash)
 
 #=====================================================
 #StaticHandler
@@ -1335,7 +1335,7 @@ class PrefixWrapper(object):
         if not hash.startswith(orig_prefix):
             raise ValueError("not a valid %s hash" % (self.wrapped.name,))
         wrapped = self.prefix + hash[len(orig_prefix):]
-        return to_native_str(wrapped)
+        return uascii_to_str(wrapped)
 
     def identify(self, hash):
         if not hash:
diff --git a/passlib/utils/md4.py b/passlib/utils/md4.py
index df3be70..a63ad11 100644
--- a/passlib/utils/md4.py
+++ b/passlib/utils/md4.py
@@ -15,8 +15,7 @@ from binascii import hexlify
 import struct
 from warnings import warn
 #site
-from passlib.utils import b, bytes, to_native_str
-from passlib.utils.compat import irange, PY3
+from passlib.utils.compat import b, bytes, bascii_to_str, irange, PY3
 #local
 __all__ = [ "md4" ]
 #=========================================================================
@@ -224,8 +223,7 @@ class md4(object):
         return out
 
     def hexdigest(self):
-        # PY3: hexlify returns bytes, but hexdigest should return str.
-        return to_native_str(hexlify(self.digest()))
+        return bascii_to_str(hexlify(self.digest()))
 
     #=========================================================================
     #eoc
diff --git a/passlib/utils/pbkdf2.py b/passlib/utils/pbkdf2.py
index c48f751..c880457 100644
--- a/passlib/utils/pbkdf2.py
+++ b/passlib/utils/pbkdf2.py
@@ -20,9 +20,8 @@ try:
 except ImportError:
     _EVP = None
 #pkg
-from passlib.utils import xor_bytes, to_bytes, b, bytes
-from passlib.utils.compat import irange, callable, int_types
-from passlib.utils.compat.aliases import BytesIO
+from passlib.utils import to_bytes, xor_bytes
+from passlib.utils.compat import b, bytes, BytesIO, irange, callable, int_types
 #local
 __all__ = [
     "hmac_sha1",