Normalized opening a file and decoding its content.

`io.open` is required on Python 2.7. Just `open` would work on Python 3.

django/core/management/commands/makemessages.py

@@ -90,7 +90,7 @@ class TranslatableFile(object):
             work_file = orig_file
             is_templatized = file_ext in command.extensions
             if is_templatized:
-                with io.open(orig_file, 'r', encoding=settings.FILE_CHARSET) as fp:
+                with io.open(orig_file, encoding=settings.FILE_CHARSET) as fp:
                     src_data = fp.read()
                 content = templatize(src_data, orig_file[2:])
                 work_file = os.path.join(self.dirpath, '%s.py' % self.file)

django/core/management/sql.py

@@ -1,6 +1,6 @@
 from __future__ import unicode_literals
 
-import codecs
+import io
 import os
 import re
 import warnings
@@ -234,7 +234,7 @@ def custom_sql_for_model(model, style, connection):
         sql_files.append(os.path.join(app_dir, "%s.sql" % opts.model_name))
     for sql_file in sql_files:
         if os.path.exists(sql_file):
-            with codecs.open(sql_file, 'r', encoding=settings.FILE_CHARSET) as fp:
+            with io.open(sql_file, encoding=settings.FILE_CHARSET) as fp:
                 output.extend(connection.ops.prepare_sql_script(fp.read(), _allow_fallback=True))
     return output
 

django/template/loaders/app_directories.py

@@ -3,6 +3,7 @@ Wrapper for loading templates from "templates" directories in INSTALLED_APPS
 packages.
 """
 
+import io
 import os
 import sys
 
@@ -56,8 +57,8 @@ class Loader(BaseLoader):
     def load_template_source(self, template_name, template_dirs=None):
         for filepath in self.get_template_sources(template_name, template_dirs):
             try:
-                with open(filepath, 'rb') as fp:
+                with io.open(filepath, encoding=settings.FILE_CHARSET) as fp:
-                    return (fp.read().decode(settings.FILE_CHARSET), filepath)
+                    return fp.read(), filepath
             except IOError:
                 pass
         raise TemplateDoesNotExist(template_name)

django/template/loaders/filesystem.py

@@ -2,6 +2,8 @@
 Wrapper for loading templates from the filesystem.
 """
 
+import io
+
 from django.conf import settings
 from django.core.exceptions import SuspiciousFileOperation
 from django.template.base import TemplateDoesNotExist
@@ -32,8 +34,8 @@ class Loader(BaseLoader):
         tried = []
         for filepath in self.get_template_sources(template_name, template_dirs):
             try:
-                with open(filepath, 'rb') as fp:
+                with io.open(filepath, encoding=settings.FILE_CHARSET) as fp:
-                    return (fp.read().decode(settings.FILE_CHARSET), filepath)
+                    return fp.read(), filepath
             except IOError:
                 tried.append(filepath)
         if tried: