Fix regression in v0.21.1, IndexEntry.path returns str

And str in Python 2 means bytes. Recall, we are supposed to give a
native experience to both Python 2 and 3 users.

pygit2/index.py

@@ -32,7 +32,7 @@ from __future__ import absolute_import, unicode_literals
 from _pygit2 import Oid, Tree, Diff
 from .errors import check_error
 from .ffi import ffi, C
-from .utils import to_bytes, is_string, strings_to_strarray
+from .utils import is_string, strings_to_strarray, to_bytes, to_str
 
 
 class Index(object):
@@ -357,7 +357,7 @@ class IndexEntry(object):
             return None
 
         entry = cls.__new__(cls)
-        entry.path = ffi.string(centry.path).decode()
+        entry.path = to_str(ffi.string(centry.path))
         entry.mode = centry.mode
         entry.id = Oid(raw=bytes(ffi.buffer(ffi.addressof(centry, 'id'))[:]))
 

pygit2/py2.py

@@ -45,3 +45,13 @@ def to_bytes(s, encoding='utf-8', errors='strict'):
 
 def is_string(s):
     return isinstance(s, basestring)
+
+
+def to_str(s):
+    if type(s) is str:
+        return s
+
+    if type(s) is unicode:
+        return s.encode()
+
+    raise TypeError, 'unexpected type "%s"' % repr(s)

pygit2/py3.py

@@ -44,3 +44,13 @@ def to_bytes(s, encoding='utf-8', errors='strict'):
 
 def is_string(s):
     return isinstance(s, str)
+
+
+def to_str(s):
+    if type(s) is str:
+        return s
+
+    if type(s) is bytes:
+        return s.decode()
+
+    raise TypeError('unexpected type "%s"' % repr(s))

pygit2/utils.py

@@ -36,9 +36,9 @@ from .ffi import ffi
 
 
 if version_info[0] < 3:
-    from .py2 import to_bytes, is_string
+    from .py2 import is_string, to_bytes, to_str
 else:
-    from .py3 import to_bytes, is_string
+    from .py3 import is_string, to_bytes, to_str