Remove enum34 as a dependency and use pure python

To resolve the persistent build problems using enum34 this patch
removes it entirely as a dependency. Instead, vanilla python classes
are used to emulate the very small enum behavior that was previously
being used.

Author: EntilZha

functional/lineage.py

@@ -1,5 +1,5 @@
 from .transformations import CACHE_T
-from .transformations import EXECUTION_STRATEGIES
+from .transformations import ExecutionStrategies
 
 
 class Lineage(object):
@@ -46,7 +46,7 @@ def evaluate(self, sequence):
         last_cache_index = self.cache_scan()
         for transform in self.transformations[last_cache_index:]:
             if transform.execution_strategies is not None \
-                    and EXECUTION_STRATEGIES.PRE_COMPUTE in transform.execution_strategies:
+                    and ExecutionStrategies.PRE_COMPUTE in transform.execution_strategies:
                 result = transform.function(list(result))
             else:
                 result = transform.function(result)

functional/transformations.py

@@ -5,7 +5,6 @@
 from itertools import dropwhile, takewhile, islice
 
 import collections
-from enum import Enum
 import types
 import six
 
@@ -17,8 +16,14 @@
     'Transformation', ['name', 'function', 'execution_strategies']
 )
 
-#: List of available execution strategies
-EXECUTION_STRATEGIES = Enum('EXECUTION_STRATEGIES', 'PRE_COMPUTE')
+
+class ExecutionStrategies(object):
+    # pylint: disable=too-few-public-methods
+    """
+    Enum like object listing the types of execution strategies
+    """
+    PRE_COMPUTE = 0
+
 
 #: Cache transformation
 CACHE_T = Transformation('cache', None, None)
@@ -308,7 +313,7 @@ def init_t():
     return Transformation(
         'init',
         lambda sequence: sequence[:-1],
-        {EXECUTION_STRATEGIES.PRE_COMPUTE}
+        {ExecutionStrategies.PRE_COMPUTE}
     )
 
 
@@ -333,7 +338,7 @@ def inits_t(wrap):
     return Transformation(
         'inits',
         lambda sequence: [wrap(sequence[:i]) for i in reversed(range(len(sequence) + 1))],
-        {EXECUTION_STRATEGIES.PRE_COMPUTE}
+        {ExecutionStrategies.PRE_COMPUTE}
     )
 
 
@@ -346,7 +351,7 @@ def tails_t(wrap):
     return Transformation(
         'tails',
         lambda sequence: [wrap(sequence[i:]) for i in range(len(sequence) + 1)],
-        {EXECUTION_STRATEGIES.PRE_COMPUTE}
+        {ExecutionStrategies.PRE_COMPUTE}
     )
 
 
@@ -495,7 +500,7 @@ def grouped_t(wrap, size):
     return Transformation(
         'grouped({0})'.format(size),
         partial(grouped_impl, wrap, size),
-        {EXECUTION_STRATEGIES.PRE_COMPUTE}
+        {ExecutionStrategies.PRE_COMPUTE}
     )
 
 

setup.py

@@ -1,16 +1,11 @@
 from setuptools import setup, find_packages
-import sys
 
 try:
     import pypandoc
     long_description = pypandoc.convert('README.md', 'rst')
 except (IOError, ImportError):
     long_description = open('README.md').read()
 
-requirements = ['future', 'six']
-if not (sys.version_info.major == 3 and sys.version_info.minor >= 4):
-    requirements.append('enum34')
-
 setup(
     name='ScalaFunctional',
     description='Package for creating data pipelines, LINQ, and chain functional programming',
@@ -24,7 +19,7 @@
     keywords='functional LINQ pipeline data collection rdd scala',
     packages=find_packages(exclude=['contrib', 'docs', 'tests*', 'test']),
     version='0.4.0',
-    install_requires=requirements,
+    install_requires=['future', 'six'],
     classifiers=[
         'Development Status :: 4 - Beta',
         'Intended Audience :: Developers',