Merge pull request #59 from firedrakeproject/py3-compat

Make GEM and TSFC mostly Python 3 compatible

.travis.yml

@@ -1,23 +1,33 @@
 notifications:
   slack:
     secure: 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
+
 language: python
 python:
   - "2.7"
+  - "3.5"
 
 env:
   - NUMPY_VERSION="==1.9.0"
   - NUMPY_VERSION=">=1.10"
 
+matrix:
+  exclude:
+  - python: "3.5"
+  include:
+  - python: "3.5"
+    env: NUMPY_VERSION=">=1.10"
+
 before_install:
   - pip install -r requirements.txt
   - pip install flake8
+  - pip install flake8-future-import
   - pip install --upgrade pytest
   - pip install --upgrade "numpy$NUMPY_VERSION"
 
 install:
   - python setup.py install
 
 script:
-  - py.test tests
   - flake8 .
+  - py.test tests

gem/__init__.py

@@ -1,3 +1,3 @@
-from __future__ import absolute_import
+from __future__ import absolute_import, print_function, division
 
 from gem.gem import *  # noqa

gem/gem.py

@@ -14,14 +14,16 @@
 indices.
 """
 
-from __future__ import absolute_import
+from __future__ import absolute_import, print_function, division
+from six import with_metaclass
 
 from abc import ABCMeta
 from itertools import chain
-import numpy
-from numpy import asarray, unique
 from operator import attrgetter
 
+import numpy
+from numpy import asarray
+
 from gem.node import Node as NodeBase
 
 
@@ -46,17 +48,15 @@ def __call__(self, *args, **kwargs):
 
         # Set free_indices if not set already
         if not hasattr(obj, 'free_indices'):
-            cfi = list(chain(*[c.free_indices for c in obj.children]))
-            obj.free_indices = tuple(unique(cfi))
+            obj.free_indices = unique(chain(*[c.free_indices
+                                              for c in obj.children]))
 
         return obj
 
 
-class Node(NodeBase):
+class Node(with_metaclass(NodeMeta, NodeBase)):
     """Abstract GEM node class."""
 
-    __metaclass__ = NodeMeta
-
     __slots__ = ('free_indices')
 
     def is_equal(self, other):
@@ -339,10 +339,9 @@ def __init__(self, condition, then, else_):
         self.shape = then.shape
 
 
-class IndexBase(object):
+class IndexBase(with_metaclass(ABCMeta)):
     """Abstract base class for indices."""
-
-    __metaclass__ = ABCMeta
+    pass
 
 IndexBase.register(int)
 
@@ -379,6 +378,10 @@ def __repr__(self):
             return "Index(%r)" % self.count
         return "Index(%r)" % self.name
 
+    def __lt__(self, other):
+        # Allow sorting of free indices in Python 3
+        return id(self) < id(other)
+
 
 class VariableIndex(IndexBase):
     """An index that is constant during a single execution of the
@@ -432,7 +435,7 @@ def __new__(cls, aggregate, multiindex):
         self.multiindex = multiindex
 
         new_indices = tuple(i for i in multiindex if isinstance(i, Index))
-        self.free_indices = tuple(unique(aggregate.free_indices + new_indices))
+        self.free_indices = unique(aggregate.free_indices + new_indices)
 
         return self
 
@@ -486,7 +489,7 @@ def __init__(self, variable, dim2idxs):
 
         self.children = (variable,)
         self.dim2idxs = dim2idxs
-        self.free_indices = tuple(unique(indices))
+        self.free_indices = unique(indices)
 
 
 class ComponentTensor(Node):
@@ -515,7 +518,7 @@ def __new__(cls, expression, multiindex):
 
         # Collect free indices
         assert set(multiindex) <= set(expression.free_indices)
-        self.free_indices = tuple(unique(list(set(expression.free_indices) - set(multiindex))))
+        self.free_indices = unique(set(expression.free_indices) - set(multiindex))
 
         return self
 
@@ -540,7 +543,7 @@ def __new__(cls, summand, index):
 
         # Collect shape and free indices
         assert index in summand.free_indices
-        self.free_indices = tuple(unique(list(set(summand.free_indices) - {index})))
+        self.free_indices = unique(set(summand.free_indices) - {index})
 
         return self
 
@@ -599,6 +602,15 @@ def get_hash(self):
         return hash((type(self), self.shape, self.children))
 
 
+def unique(indices):
+    """Sorts free indices and eliminates duplicates.
+
+    :arg indices: iterable of indices
+    :returns: sorted tuple of unique free indices
+    """
+    return tuple(sorted(set(indices), key=id))
+
+
 def partial_indexed(tensor, indices):
     """Generalised indexing into a tensor.  The number of indices may
     be less than or equal to the rank of the tensor, so the result may

gem/impero.py

@@ -10,7 +10,8 @@
    (Command?) after clicking on them.
 """
 
-from __future__ import absolute_import
+from __future__ import absolute_import, print_function, division
+from six import with_metaclass
 
 from abc import ABCMeta, abstractmethod
 
@@ -23,11 +24,9 @@ class Node(NodeBase):
     __slots__ = ()
 
 
-class Terminal(Node):
+class Terminal(with_metaclass(ABCMeta, Node)):
     """Abstract class for terminal Impero nodes"""
 
-    __metaclass__ = ABCMeta
-
     __slots__ = ()
 
     children = ()

gem/impero_utils.py

@@ -6,7 +6,8 @@
 C code or a COFFEE AST.
 """
 
-from __future__ import absolute_import
+from __future__ import absolute_import, print_function, division
+from six.moves import zip
 
 import collections
 import itertools
@@ -57,11 +58,14 @@ def compile_gem(return_variables, expressions, prefix_ordering, remove_zeros=Fal
     indices = []
     for node in traversal(expressions):
         if isinstance(node, gem.Indexed):
-            indices.extend(node.multiindex)
+            for index in node.multiindex:
+                if isinstance(index, gem.Index):
+                    indices.append(index)
         elif isinstance(node, gem.FlexiblyIndexed):
             for offset, idxs in node.dim2idxs:
                 for index, stride in idxs:
-                    indices.append(index)
+                    if isinstance(index, gem.Index):
+                        indices.append(index)
     # The next two lines remove duplicate elements from the list, but
     # preserve the ordering, i.e. all elements will appear only once,
     # in the order of their first occurance in the original list.
@@ -75,7 +79,7 @@ def compile_gem(return_variables, expressions, prefix_ordering, remove_zeros=Fal
     get_indices = lambda expr: apply_ordering(expr.free_indices)
 
     # Build operation ordering
-    ops = scheduling.emit_operations(zip(return_variables, expressions), get_indices)
+    ops = scheduling.emit_operations(list(zip(return_variables, expressions)), get_indices)
 
     # Empty kernel
     if len(ops) == 0:
@@ -177,7 +181,7 @@ def make_loop_tree(ops, get_indices, level=0):
         else:
             statements.extend(op_group)
     # Remove no-op terminals from the tree
-    statements = filter(lambda s: not isinstance(s, imp.Noop), statements)
+    statements = [s for s in statements if not isinstance(s, imp.Noop)]
     return imp.Block(statements)
 
 

gem/interpreter.py

@@ -1,7 +1,8 @@
 """
 An interpreter for GEM trees.
 """
-from __future__ import absolute_import
+from __future__ import absolute_import, print_function, division
+from six.moves import map
 
 import numpy
 import operator
@@ -302,4 +303,4 @@ def evaluate(expressions, bindings=None):
         exprs = (expressions, )
     mapper = node.Memoizer(_evaluate)
     mapper.bindings = bindings if bindings is not None else {}
-    return map(mapper, exprs)
+    return list(map(mapper, exprs))

gem/node.py

@@ -1,7 +1,8 @@
 """Generic abstract node class and utility functions for creating
 expression DAG languages."""
 
-from __future__ import absolute_import
+from __future__ import absolute_import, print_function, division
+from six.moves import map
 
 import collections
 
@@ -201,7 +202,7 @@ def __call__(self, node, arg):
 
 def reuse_if_untouched(node, self):
     """Reuse if untouched recipe"""
-    new_children = map(self, node.children)
+    new_children = list(map(self, node.children))
     if all(nc == c for nc, c in zip(new_children, node.children)):
         return node
     else:

gem/optimise.py

@@ -1,8 +1,10 @@
 """A set of routines implementing various transformations on GEM
 expressions."""
 
-from __future__ import absolute_import
+from __future__ import absolute_import, print_function, division
+from six.moves import map
 
+from functools import reduce
 from singledispatch import singledispatch
 
 from gem.node import Memoizer, MemoizerArg, reuse_if_untouched, reuse_if_untouched_arg
@@ -111,4 +113,4 @@ def unroll_indexsum(expressions, max_extent):
     """
     mapper = Memoizer(_unroll_indexsum)
     mapper.max_extent = max_extent
-    return map(mapper, expressions)
+    return list(map(mapper, expressions))

gem/scheduling.py

@@ -1,7 +1,7 @@
 """Schedules operations to evaluate a multi-root expression DAG,
 forming an ordered list of Impero terminals."""
 
-from __future__ import absolute_import
+from __future__ import absolute_import, print_function, division
 
 import collections
 import functools

requirements-ext.txt

@@ -1,2 +1,3 @@
 numpy
 singledispatch
+six

setup.cfg

@@ -1,3 +1,7 @@
 [flake8]
-ignore = E501,E226,E731
-exclude = .git,__pycache__
+ignore =
+    E501,E226,E731,
+    FI14,FI54,
+    FI50,FI51,FI53
+exclude = .git,__pycache__,build,dist
+min-version = 2.7

setup.py

@@ -1,3 +1,5 @@
+from __future__ import print_function, division, absolute_import
+
 from distutils.core import setup
 
 version = "0.0.1"

tests/test_codegen.py

@@ -1,3 +1,5 @@
+from __future__ import absolute_import, print_function, division
+
 import pytest
 
 from gem import impero_utils

tests/test_create_element.py

@@ -1,3 +1,4 @@
+from __future__ import absolute_import, print_function, division
 from tsfc import fiatinterface as f
 import pytest
 import ufl

tests/test_idempotency.py

@@ -1,3 +1,4 @@
+from __future__ import absolute_import, print_function, division
 import ufl
 from tsfc import compile_form
 import pytest

tsfc/__init__.py

@@ -1,3 +1,3 @@
-from __future__ import absolute_import
+from __future__ import absolute_import, print_function, division
 
 from tsfc.driver import compile_form  # noqa

tsfc/coffee.py

@@ -2,9 +2,10 @@
 
 This is the final stage of code generation in TSFC."""
 
-from __future__ import absolute_import
+from __future__ import absolute_import, print_function, division
 
 from collections import defaultdict
+from functools import reduce
 from math import isnan
 import itertools
 

tsfc/compat.py

@@ -1,6 +1,7 @@
 """
 Backwards compatibility for some functionality.
 """
+from __future__ import absolute_import, print_function, division
 import numpy
 from distutils.version import StrictVersion
 

tsfc/constants.py

@@ -1,4 +1,4 @@
-from __future__ import absolute_import
+from __future__ import absolute_import, print_function, division
 
 import numpy
 

tsfc/driver.py

@@ -1,7 +1,9 @@
-from __future__ import absolute_import
+from __future__ import absolute_import, print_function, division
+from six.moves import range
 
 import collections
 import time
+from functools import reduce
 
 from ufl.classes import Form
 from ufl.log import GREEN
@@ -277,6 +279,6 @@ def lower_integral_type(fiat_cell, integral_type):
     elif integral_type == 'exterior_facet_top':
         entity_ids = [1]
     else:
-        entity_ids = range(len(fiat_cell.get_topology()[integration_dim]))
+        entity_ids = list(range(len(fiat_cell.get_topology()[integration_dim])))
 
     return integration_dim, entity_ids