PY2, gitpython-developers#519: FIX GitCommandError.tostr() encoding issue

+ PY3 means "PY3 or later" (TODO: fix also for  *gitdb* project).

Author: ankostis

git/compat.py

@@ -11,7 +11,6 @@
 import sys
 
 from gitdb.utils.compat import (
-    PY3,
     xrange,
     MAXSIZE,
     izip,
@@ -24,7 +23,9 @@
     force_text
 )
 
+PY3 = sys.version_info[0] >= 3
 defenc = sys.getdefaultencoding()
+
 if PY3:
     import io
     FileType = io.IOBase
@@ -74,13 +75,8 @@ def __new__(cls, name, nbases, d):
             # we set the __metaclass__ attribute explicitly
             if not PY3 and '___metaclass__' not in d:
                 d['__metaclass__'] = meta
-            # end
             return meta(name, bases, d)
-        # end
-    # end metaclass
     return metaclass(meta.__name__ + 'Helper', None, {})
-    # end handle py2
-
 
 def is_win():
     return os.name == 'nt'
@@ -93,3 +89,16 @@ def is_posix():
 def is_darwin():
     return os.name == 'darwin'
 
+
+## From https://docs.python.org/3.3/howto/pyporting.html
+class UnicodeMixin(object):
+
+    """Mixin class to handle defining the proper __str__/__unicode__
+    methods in Python 2 or 3."""
+
+    if sys.version_info[0] >= 3: # Python 3
+        def __str__(self):
+            return self.__unicode__()
+    else:  # Python 2
+        def __str__(self):
+            return self.__unicode__().encode('utf8')

git/exc.py

@@ -6,8 +6,7 @@
 """ Module containing all exceptions thrown througout the git package, """
 
 from gitdb.exc import *     # NOQA
-
-from git.compat import defenc
+from git.compat import UnicodeMixin, safe_decode
 
 
 class InvalidGitRepositoryError(Exception):
@@ -28,7 +27,7 @@ class GitCommandNotFound(Exception):
     pass
 
 
-class GitCommandError(Exception):
+class GitCommandError(UnicodeMixin, Exception):
     """ Thrown if execution of the git command fails with non-zero status code. """
 
     def __init__(self, command, status, stderr=None, stdout=None):
@@ -37,13 +36,13 @@ def __init__(self, command, status, stderr=None, stdout=None):
         self.status = status
         self.command = command
 
-    def __str__(self):
-        ret = "'%s' returned with exit code %i" % \
-              (' '.join(str(i) for i in self.command), self.status)
+    def __unicode__(self):
+        ret = u"'%s' returned with exit code %s" % \
+              (u' '.join(safe_decode(i) for i in self.command), self.status)
         if self.stderr:
-            ret += "\nstderr: '%s'" % self.stderr.decode(defenc)
+            ret += u"\nstderr: '%s'" % safe_decode(self.stderr)
         if self.stdout:
-            ret += "\nstdout: '%s'" % self.stdout.decode(defenc)
+            ret += u"\nstdout: '%s'" % safe_decode(self.stdout)
         return ret