python: Add __future__ imports for python 3 compatibility

Except for src/ext, which we may not want to modify.

Closes ticket 32732.

6 files changed, 24 insertions, 1 deletions

diff --git a/scripts/maint/practracker/includes.py b/scripts/maint/practracker/includes.py
index ed0e11ef28..fe0f32e253 100755
--- a/scripts/maint/practracker/includes.py
+++ b/scripts/maint/practracker/includes.py
@@ -19,8 +19,10 @@
    Advisory .may_include files only result in warnings, rather than errors.
 """
 
-
+# Future imports for Python 2.7, mandatory in 3.0
+from __future__ import division
 from __future__ import print_function
+from __future__ import unicode_literals
 
 import fnmatch
 import os
diff --git a/scripts/maint/practracker/metrics.py b/scripts/maint/practracker/metrics.py
index 4c62bc2425..ae88b84f31 100644
--- a/scripts/maint/practracker/metrics.py
+++ b/scripts/maint/practracker/metrics.py
@@ -4,6 +4,11 @@
 # These are currently ad-hoc string operations and regexps.
 # We might want to use a proper static analysis library in the future, if we want to get more advanced metrics.
 
+# Future imports for Python 2.7, mandatory in 3.0
+from __future__ import division
+from __future__ import print_function
+from __future__ import unicode_literals
+
 import re
 
 def get_file_len(f):
diff --git a/scripts/maint/practracker/practracker.py b/scripts/maint/practracker/practracker.py
index 5f26d28cea..e1845c43e3 100755
--- a/scripts/maint/practracker/practracker.py
+++ b/scripts/maint/practracker/practracker.py
@@ -19,7 +19,10 @@ problems in the Tor source, use the --regen flag:
   $ python3 --regen ./scripts/maint/practracker/practracker.py .
 """
 
+# Future imports for Python 2.7, mandatory in 3.0
+from __future__ import division
 from __future__ import print_function
+from __future__ import unicode_literals
 
 import os, sys
 
diff --git a/scripts/maint/practracker/practracker_tests.py b/scripts/maint/practracker/practracker_tests.py
index 45719d6cb7..8d0418880c 100755
--- a/scripts/maint/practracker/practracker_tests.py
+++ b/scripts/maint/practracker/practracker_tests.py
@@ -2,6 +2,11 @@
 
 """Some simple tests for practracker metrics"""
 
+# Future imports for Python 2.7, mandatory in 3.0
+from __future__ import division
+from __future__ import print_function
+from __future__ import unicode_literals
+
 import unittest
 
 try:
diff --git a/scripts/maint/practracker/problem.py b/scripts/maint/practracker/problem.py
index d21840a213..bee5eeb903 100644
--- a/scripts/maint/practracker/problem.py
+++ b/scripts/maint/practracker/problem.py
@@ -7,7 +7,10 @@ problem is worse than a registered exception so that it only warns when things
 get worse.
 """
 
+# Future imports for Python 2.7, mandatory in 3.0
+from __future__ import division
 from __future__ import print_function
+from __future__ import unicode_literals
 
 import os.path
 import re
diff --git a/scripts/maint/practracker/util.py b/scripts/maint/practracker/util.py
index db02a983f8..c52ca2fbbf 100644
--- a/scripts/maint/practracker/util.py
+++ b/scripts/maint/practracker/util.py
@@ -1,3 +1,8 @@
+# Future imports for Python 2.7, mandatory in 3.0
+from __future__ import division
+from __future__ import print_function
+from __future__ import unicode_literals
+
 import os
 
 # We don't want to run metrics for unittests, automatically-generated C files,