[BEAM-4007] Futurize typehints subpackage

sdks/python/apache_beam/typehints/__init__.py

@@ -17,6 +17,8 @@
 
 """A package defining the syntax and decorator semantics for type-hints."""
 
+from __future__ import absolute_import
+
 # pylint: disable=wildcard-import
 from apache_beam.typehints.typehints import *
 from apache_beam.typehints.decorators import *

sdks/python/apache_beam/typehints/decorators.py

@@ -83,8 +83,13 @@ def foo((a, b)):
 defined, or before importing a module containing type-hinted functions.
 """
 
+from __future__ import absolute_import
+
 import inspect
 import types
+from builtins import next
+from builtins import object
+from builtins import zip
 
 from apache_beam.typehints import native_type_compatibility
 from apache_beam.typehints import typehints
@@ -175,7 +180,7 @@ def with_defaults(self, hints):
     return IOTypeHints(self.input_types or hints.input_types,
                        self.output_types or hints.output_types)
 
-  def __nonzero__(self):
+  def __bool__(self):
     return bool(self.input_types or self.output_types)
 
   def __repr__(self):
@@ -404,7 +409,7 @@ def with_output_types(*return_type_hint, **kwargs):
     from apache_beam.typehints import with_output_types
     from apache_beam.typehints import Set
 
-    class Coordinate:
+    class Coordinate(object):
       def __init__(self, x, y):
         self.x = x
         self.y = y

sdks/python/apache_beam/typehints/native_type_compatibility.py

@@ -17,8 +17,12 @@
 
 """Module to convert Python's native typing types to Beam types."""
 
+from __future__ import absolute_import
+
 import collections
 import typing
+from builtins import next
+from builtins import range
 
 from apache_beam.typehints import typehints
 

sdks/python/apache_beam/typehints/native_type_compatibility_test.py

@@ -17,6 +17,8 @@
 
 """Test for Beam type compatibility library."""
 
+from __future__ import absolute_import
+
 import typing
 import unittest
 

sdks/python/apache_beam/typehints/opcodes.py

@@ -33,8 +33,6 @@
 import types
 from functools import reduce
 
-import six
-
 from . import typehints
 from .trivial_inference import BoundMethod
 from .trivial_inference import Const
@@ -47,6 +45,11 @@
 from .typehints import Tuple
 from .typehints import Union
 
+try:                # Python 2
+  unicode           # pylint: disable=unicode-builtin
+except NameError:   # Python 3
+  unicode = str
+
 
 def pop_one(state, unused_arg):
   del state.stack[-1:]
@@ -152,7 +155,7 @@ def binary_true_divide(state, unused_arg):
 def binary_subscr(state, unused_arg):
   index = state.stack.pop()
   base = state.stack.pop()
-  if base in (str, six.text_type):
+  if base in (str, unicode):
     out = base
   elif (isinstance(index, Const) and isinstance(index.value, int)
         and isinstance(base, typehints.TupleHint.TupleConstraint)):

sdks/python/apache_beam/typehints/trivial_inference.py

@@ -28,11 +28,19 @@
 import pprint
 import sys
 import types
+from builtins import object
+from builtins import zip
 from functools import reduce
 
 from apache_beam.typehints import Any
 from apache_beam.typehints import typehints
-from six.moves import builtins
+
+# pylint: disable=wrong-import-order, wrong-import-position, ungrouped-imports
+try:                  # Python 2
+  import __builtin__ as builtins
+except ImportError:   # Python 3
+  import builtins
+# pylint: enable=wrong-import-order, wrong-import-position, ungrouped-imports
 
 
 class TypeInferenceError(ValueError):
@@ -115,6 +123,9 @@ def __init__(self, f, local_vars=None, stack=()):
   def __eq__(self, other):
     return isinstance(other, FrameState) and self.__dict__ == other.__dict__
 
+  def __hash__(self):
+    return hash(tuple(sorted(self.__dict__.items())))
+
   def copy(self):
     return FrameState(self.f, self.vars, self.stack)
 

sdks/python/apache_beam/typehints/trivial_inference_test.py

@@ -16,6 +16,9 @@
 #
 
 """Tests for apache_beam.typehints.trivial_inference."""
+
+from __future__ import absolute_import
+
 import unittest
 
 from apache_beam.typehints import trivial_inference

sdks/python/apache_beam/typehints/typecheck.py

@@ -20,13 +20,13 @@
 For internal use only; no backwards-compatibility guarantees.
 """
 
+from __future__ import absolute_import
 
 import collections
 import inspect
-import sys
 import types
 
-import six
+from future.utils import raise_with_traceback
 
 from apache_beam import pipeline
 from apache_beam.pvalue import TaggedOutput
@@ -41,6 +41,11 @@
 from apache_beam.typehints.typehints import SimpleTypeHintError
 from apache_beam.typehints.typehints import check_constraint
 
+try:                # Python 2
+  unicode           # pylint: disable=unicode-builtin
+except NameError:   # Python 3
+  unicode = str
+
 
 class AbstractDoFnWrapper(DoFn):
   """An abstract class to create wrapper around DoFn"""
@@ -87,14 +92,14 @@ def wrapper(self, method, args, kwargs):
     except TypeCheckError as e:
       error_msg = ('Runtime type violation detected within ParDo(%s): '
                    '%s' % (self.full_label, e))
-      six.raise_from(TypeCheckError(error_msg), sys.exc_info()[2])
+      raise_with_traceback(TypeCheckError(error_msg))
     else:
       return self._check_type(result)
 
   def _check_type(self, output):
     if output is None:
       return output
-    elif isinstance(output, (dict,) + six.string_types):
+    elif isinstance(output, (dict, bytes, str, unicode)):
       object_type = type(output).__name__
       raise TypeCheckError('Returning a %s from a ParDo or FlatMap is '
                            'discouraged. Please use list("%s") if you really '
@@ -176,12 +181,12 @@ def _type_check(self, type_constraint, datum, is_input):
     try:
       check_constraint(type_constraint, datum)
     except CompositeTypeHintError as e:
-      six.raise_from(TypeCheckError(e.args[0]), sys.exc_info()[2])
+      raise_with_traceback(TypeCheckError(e.args[0]))
     except SimpleTypeHintError:
       error_msg = ("According to type-hint expected %s should be of type %s. "
                    "Instead, received '%s', an instance of type %s."
                    % (datum_type, type_constraint, datum, type(datum)))
-      six.raise_from(TypeCheckError(error_msg), sys.exc_info()[2])
+      raise_with_traceback(TypeCheckError(error_msg))
 
 
 class TypeCheckCombineFn(core.CombineFn):
@@ -206,7 +211,7 @@ def add_input(self, accumulator, element, *args, **kwargs):
       except TypeCheckError as e:
         error_msg = ('Runtime type violation detected within %s: '
                      '%s' % (self._label, e))
-        six.raise_from(TypeCheckError(error_msg), sys.exc_info()[2])
+        raise_with_traceback(TypeCheckError(error_msg))
     return self._combinefn.add_input(accumulator, element, *args, **kwargs)
 
   def merge_accumulators(self, accumulators, *args, **kwargs):
@@ -221,7 +226,7 @@ def extract_output(self, accumulator, *args, **kwargs):
       except TypeCheckError as e:
         error_msg = ('Runtime type violation detected within %s: '
                      '%s' % (self._label, e))
-        six.raise_from(TypeCheckError(error_msg), sys.exc_info()[2])
+        raise_with_traceback(TypeCheckError(error_msg))
     return result
 
 

sdks/python/apache_beam/typehints/typed_pipeline_test.py

@@ -16,6 +16,9 @@
 #
 
 """Unit tests for the type-hint objects and decorators."""
+
+from __future__ import absolute_import
+
 import inspect
 import typing
 import unittest

sdks/python/apache_beam/typehints/typehints.py

@@ -63,12 +63,16 @@
 
 """
 
+from __future__ import absolute_import
+
 import collections
 import copy
 import sys
 import types
+from builtins import next
+from builtins import zip
 
-import six
+from future.utils import with_metaclass
 
 __all__ = [
     'Any',
@@ -411,17 +415,25 @@ def __eq__(self, other):
   def __repr__(self):
     return 'Any'
 
+  def __hash__(self):
+    # TODO(BEAM - 3730)
+    return hash(id(self))
+
   def type_check(self, instance):
     pass
 
 
 class TypeVariable(AnyTypeConstraint):
 
+  def __init__(self, name):
+    self.name = name
+
   def __eq__(self, other):
     return type(self) == type(other) and self.name == other.name
 
-  def __init__(self, name):
-    self.name = name
+  def __hash__(self):
+    # TODO(BEAM - 3730)
+    return hash(id(self))
 
   def __repr__(self):
     return 'TypeVariable[%s]' % self.name
@@ -992,8 +1004,8 @@ def __getitem__(self, type_param):
 IteratorTypeConstraint = IteratorHint.IteratorTypeConstraint
 
 
-@six.add_metaclass(GetitemConstructor)
-class WindowedTypeConstraint(TypeConstraint):
+class WindowedTypeConstraint(with_metaclass(GetitemConstructor,
+                                            TypeConstraint)):
   """A type constraint for WindowedValue objects.
 
   Mostly for internal use.

sdks/python/apache_beam/typehints/typehints_test.py

@@ -16,9 +16,14 @@
 #
 
 """Unit tests for the type-hint objects and decorators."""
+
+from __future__ import absolute_import
+
 import functools
 import inspect
 import unittest
+from builtins import next
+from builtins import range
 
 import apache_beam.typehints.typehints as typehints
 from apache_beam.typehints import Any

sdks/python/tox.ini

@@ -113,6 +113,7 @@ modules =
   apache_beam/pvalue_test
   apache_beam/testing
   apache_beam/tools
+  apache_beam/typehints
 commands =
   python --version
   pip --version