Python3.6 compatibility

- Work with Python 3.6
- Fix for unittest
- Update .travis.yml for python3.6
- (Re)Compatibility with Python2.7

.travis.yml

@@ -1,5 +1,6 @@
 language: python
 python:
   - "2.7"
+  - "3.6"
 install: "pip install -r requirements.txt"
 script: nosetests

bin/view_trace

@@ -1,5 +1,7 @@
 #!/usr/bin/env python
-
+from __future__ import print_function
 from execution_trace.viewer.viewer import main
-print "Starting UI web server, please open the URL listed below."
-main()
+
+if __name__ == '__main__':
+    print("Starting UI web server, please open the URL listed below.")
+    main()

example.py

@@ -1,3 +1,4 @@
+from __future__ import print_function
 from collections import defaultdict
 import re
 
@@ -13,6 +14,5 @@ def wordcount(text):
 
 
 if __name__ == '__main__':
-    print wordcount('Hello, world!')
-    print wordcount('echo echo echo echo')
-
+    print(wordcount('Hello, world!'))
+    print(wordcount('echo echo echo echo'))

execution_trace/constants.py

@@ -1,4 +1,5 @@
 from voluptuous import Schema, Required
+from builtins import str
 
 RECORD_FN_NAME = '_record_state_fn_hidden_123'
 RETVAL_NAME = '_retval_hidden_123'
@@ -14,5 +15,5 @@
 })
 
 SOURCE_DUMP_SCHEMA = Schema({
-    Required('source'): basestring
+    Required('source'): str     # Python 2.7 & 3.x
 })

execution_trace/record.py

@@ -1,4 +1,10 @@
+from future.utils import viewitems
 import ast
+# Python 2 and 3
+try:
+    from ast import TryExcept as Try
+except ImportError:
+    from ast import Try
 import inspect
 import json
 import logging
@@ -30,7 +36,8 @@ def _record_state_fn_hidden_123(lineno, f_locals):
     """Stores local line data."""
 
     # Make sure we have just primitive types.
-    f_locals = {k: repr(v) for k, v in f_locals.iteritems()}
+    f_locals = {k: repr(v) for k, v in viewitems(f_locals)}  # Python 2 and 3
+
     data = {
         'lineno': lineno,
         'state': f_locals,
@@ -44,6 +51,8 @@ def _record_state_fn_hidden_123(lineno, f_locals):
 # TL;DR need this because the decorator would
 # recursively apply on the new generated function.
 _blocked = False
+
+
 def record(num_executions=1):
     def _record(f):
         """Transforms `f` such that after every line record_state is called.
@@ -76,7 +85,9 @@ def _record(f):
         env[RECORD_FN_NAME] = globals()[RECORD_FN_NAME]
 
         _blocked = True
-        exec new_f_compiled in env
+        # https://stackoverflow.com/questions/15086040/behavior-of-exec-function-in-python-2-and-python-3
+        exec(new_f_compiled, env)  # Python 2 and 3
+
         _blocked = False
 
         # Keep a reference to the (original) mangled function, because our decorator
@@ -135,6 +146,7 @@ def wrapped(*args, **kwargs):
             return ret
 
         return wrapped
+
     return _record
 
 
@@ -203,7 +215,7 @@ def _fill_body_with_record(original_body, prepend=False, lineno=None):
             has_nested = True
 
             # Don't want to prepend call for try/except, but we want for the others.
-            if isinstance(item, ast.TryExcept):
+            if isinstance(item, Try):
                 prepend = False
             else:
                 prepend = True

execution_trace/tests/test_record.py

@@ -1,14 +1,19 @@
 import importlib
 import json
 import mock
-import StringIO
+from sys import version_info
 import unittest
-
+#
 from parameterized import parameterized
-
+#
 from execution_trace import record
 from execution_trace.constants import SOURCE_DUMP_SCHEMA, EXECUTION_DUMP_SCHEMA, RECORD_FN_NAME
 
+if version_info[0] < 3:
+    from StringIO import StringIO   # Python 2.7
+else:
+    # https://stackoverflow.com/questions/11914472/stringio-in-python3
+    from io import StringIO     # Python 3.x
 
 # Covers all supported syntax. See `execution_trace.tests.functions`
 # package for context.
@@ -44,7 +49,7 @@ def setUp(self):
 
         self.get_dump_file_patcher = mock.patch('execution_trace.record._get_dump_file')
         self.get_dump_file = self.get_dump_file_patcher.start()
-        self.dump_file = StringIO.StringIO()
+        self.dump_file = StringIO()
         self.get_dump_file.return_value = self.dump_file, '/tmp/mock_path'
 
     def tearDown(self):
@@ -157,8 +162,7 @@ def f():  # 2
 
         expected_trace = [{u'data': [{u'lineno': 3, u'state': {}},
                                      {u'lineno': 4, u'state': {u'x': u'5'}}]}]
-        self._check_dump_file(self.dump_file, expected_trace==expected_trace)
-
+        self._check_dump_file(self.dump_file, expected_trace == expected_trace)
 
     def _check_dump_file(self, dump_file, num_executions=1, expected_trace=None):
         # Rewind the file.

requirements.txt

@@ -3,3 +3,4 @@ mock==1.3.0
 nose==1.3.7
 voluptuous==0.8.10
 Flask==0.10.1
+future==0.16.0

setup.py

@@ -1,7 +1,5 @@
 from setuptools import setup
 
-
-
 setup(name='execution-trace',
       version='1.1.0',
       description="Trace the local context of a Python function's execution with just a decorator",
@@ -13,17 +11,17 @@
                 'execution_trace.viewer'],
       include_package_data=True,
       install_requires=[
-            'voluptuous==0.8.10',
-            'Flask==0.10.1',
+          'voluptuous==0.8.10',
+          'Flask==0.10.1',
       ],
       test_suite='nose.collector',
       tests_require=[
-            'nose==1.3.7',
-            'mock==1.3.0',
-            'parameterized==0.6.1',
+          'nose==1.3.7',
+          'mock==1.3.0',
+          'parameterized==0.6.1',
       ],
       scripts=[
-            'bin/view_trace',
+          'bin/view_trace',
       ],
       zip_safe=False
-)
+      )