Removed code that is not needed any more

Close #219
Close #218

pint/compat/__init__.py

@@ -65,11 +65,6 @@ try:
 except ImportError:
     from .chainmap import ChainMap
 
-try:
-    from collections import TransformDict
-except ImportError:
-    from .transformdict import TransformDict
-
 try:
     from functools import lru_cache
 except ImportError:

pint/compat/transformdict.py

@@ -1,136 +0,0 @@
-# -*- coding: utf-8 -*-
-"""
-    pint.compat.transformdict
-    ~~~~~~~~~~~~~~~~~~~~~~~~~
-
-    Taken from the Python 3.4 source code.
-
-    :copyright: 2013, PSF
-    :license: PSF License
-"""
-
-from collections import MutableMapping
-
-_sentinel = object()
-
-class TransformDict(MutableMapping):
-    '''Dictionary that calls a transformation function when looking
-    up keys, but preserves the original keys.
-
-    >>> d = TransformDict(str.lower)
-    >>> d['Foo'] = 5
-    >>> d['foo'] == d['FOO'] == d['Foo'] == 5
-    True
-    >>> set(d.keys())
-    {'Foo'}
-    '''
-
-    __slots__ = ('_transform', '_original', '_data')
-
-    def __init__(self, transform, init_dict=None, **kwargs):
-        '''Create a new TransformDict with the given *transform* function.
-        *init_dict* and *kwargs* are optional initializers, as in the
-        dict constructor.
-        '''
-        if not callable(transform):
-            raise TypeError("expected a callable, got %r" % transform.__class__)
-        self._transform = transform
-        # transformed => original
-        self._original = {}
-        self._data = {}
-        if init_dict:
-            self.update(init_dict)
-        if kwargs:
-            self.update(kwargs)
-
-    def getitem(self, key):
-        'D.getitem(key) -> (stored key, value)'
-        transformed = self._transform(key)
-        original = self._original[transformed]
-        value = self._data[transformed]
-        return original, value
-
-    @property
-    def transform_func(self):
-        "This TransformDict's transformation function"
-        return self._transform
-
-    # Minimum set of methods required for MutableMapping
-
-    def __len__(self):
-        return len(self._data)
-
-    def __iter__(self):
-        return iter(self._original.values())
-
-    def __getitem__(self, key):
-        return self._data[self._transform(key)]
-
-    def __setitem__(self, key, value):
-        transformed = self._transform(key)
-        self._data[transformed] = value
-        self._original.setdefault(transformed, key)
-
-    def __delitem__(self, key):
-        transformed = self._transform(key)
-        del self._data[transformed]
-        del self._original[transformed]
-
-    # Methods overriden to mitigate the performance overhead.
-
-    def clear(self):
-        'D.clear() -> None.  Remove all items from D.'
-        self._data.clear()
-        self._original.clear()
-
-    def __contains__(self, key):
-        return self._transform(key) in self._data
-
-    def get(self, key, default=None):
-        'D.get(k[,d]) -> D[k] if k in D, else d.  d defaults to None.'
-        return self._data.get(self._transform(key), default)
-
-    def pop(self, key, default=_sentinel):
-        '''D.pop(k[,d]) -> v, remove specified key and return the corresponding value.
-          If key is not found, d is returned if given, otherwise KeyError is raised.
-        '''
-        transformed = self._transform(key)
-        if default is _sentinel:
-            del self._original[transformed]
-            return self._data.pop(transformed)
-        else:
-            self._original.pop(transformed, None)
-            return self._data.pop(transformed, default)
-
-    def popitem(self):
-        '''D.popitem() -> (k, v), remove and return some (key, value) pair
-           as a 2-tuple; but raise KeyError if D is empty.
-        '''
-        transformed, value = self._data.popitem()
-        return self._original.pop(transformed), value
-
-    # Other methods
-
-    def copy(self):
-        'D.copy() -> a shallow copy of D'
-        other = self.__class__(self._transform)
-        other._original = self._original.copy()
-        other._data = self._data.copy()
-        return other
-
-    __copy__ = copy
-
-    def __getstate__(self):
-        return (self._transform, self._data, self._original)
-
-    def __setstate__(self, state):
-        self._transform, self._data, self._original = state
-
-    def __repr__(self):
-        try:
-            equiv = dict(self)
-        except TypeError:
-            # Some keys are unhashable, fall back on .items()
-            equiv = list(self.items())
-        return '%s(%r, %s)' % (self.__class__.__name__,
-                               self._transform, repr(equiv))

pint/context.py

@@ -27,16 +27,6 @@ _header_re = re.compile('@context\s*(?P<defaults>\(.*\))?\s+(?P<name>\w+)\s*(=(?
 _varname_re = re.compile('[A-Za-z_][A-Za-z0-9_]*')
 
 
-def _freeze(d):
-    """Return a hashable view of dict.
-    """
-    if isinstance(d, string_types):
-        d = ParserHelper.from_string(d)
-    if isinstance(d, frozenset):
-        return d
-    return frozenset(d.items())
-
-
 def _expression_to_function(eq):
     def func(ureg, value, **kwargs):
         return ureg.parse_expression(eq, value=value, **kwargs)

pint/testsuite/test_contexts.py

@@ -6,7 +6,7 @@ import itertools
 from collections import defaultdict
 
 from pint import UnitRegistry
-from pint.context import Context, _freeze
+from pint.context import Context
 from pint.util import UnitsContainer
 from pint.testsuite import QuantityTestCase
 
@@ -81,17 +81,6 @@ def add_sharedargdef_ctxs(ureg):
 
 class TestContexts(QuantityTestCase):
 
-    def test_freeze(self):
-        self.assertEqual(_freeze('meter'), frozenset([('meter', 1)]))
-        self.assertEqual(_freeze('meter/second'), frozenset((('meter', 1), ('second', -1))))
-        x = frozenset((('meter', 1)))
-        self.assertIs(_freeze(x), x)
-        self.assertEqual(_freeze({'meter': 1}),
-                         frozenset([('meter', 1)]))
-        self.assertEqual(_freeze({'meter': -1, 'second': -1}),
-                         frozenset((('meter', -1), ('second', -1))))
-
-
     def test_known_context(self):
         ureg = UnitRegistry()
         add_ctxs(ureg)