Beispiel #1
0
 def _get_async_expr_replacement(
         self, node: cst.CSTNode) -> Optional[cst.CSTNode]:
     if m.matches(node, m.Call()):
         node = cast(cst.Call, node)
         return self._get_async_call_replacement(node)
     elif m.matches(node, m.Attribute()):
         node = cast(cst.Attribute, node)
         return self._get_async_attr_replacement(node)
     elif m.matches(node, m.UnaryOperation(operator=m.Not())):
         node = cast(cst.UnaryOperation, node)
         replacement_expression = self._get_async_expr_replacement(
             node.expression)
         if replacement_expression is not None:
             return node.with_changes(expression=replacement_expression)
     elif m.matches(node, m.BooleanOperation()):
         node = cast(cst.BooleanOperation, node)
         maybe_left = self._get_async_expr_replacement(node.left)
         maybe_right = self._get_async_expr_replacement(node.right)
         if maybe_left is not None or maybe_right is not None:
             left_replacement = maybe_left if maybe_left is not None else node.left
             right_replacement = (maybe_right if maybe_right is not None
                                  else node.right)
             return node.with_changes(left=left_replacement,
                                      right=right_replacement)
     return None
    def _extract_static_bool(cls, node: cst.BaseExpression) -> Optional[bool]:
        if m.matches(node, m.Call()):
            # cannot reason about function calls
            return None
        if m.matches(node, m.UnaryOperation(operator=m.Not())):
            sub_value = cls._extract_static_bool(
                cst.ensure_type(node, cst.UnaryOperation).expression)
            if sub_value is None:
                return None
            return not sub_value

        if m.matches(node, m.Name("True")):
            return True

        if m.matches(node, m.Name("False")):
            return False

        if m.matches(node, m.BooleanOperation()):
            node = cst.ensure_type(node, cst.BooleanOperation)
            left_value = cls._extract_static_bool(node.left)
            right_value = cls._extract_static_bool(node.right)
            if m.matches(node.operator, m.Or()):
                if right_value is True or left_value is True:
                    return True

            if m.matches(node.operator, m.And()):
                if right_value is False or left_value is False:
                    return False

        return None
Beispiel #3
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 def visit_UnaryOperation(self, node: cst.UnaryOperation) -> None:
     if m.matches(node, m.UnaryOperation(operator=m.Not(), expression=m.Name())):
         # Eg: "not x".
         expression: cst.Name = cast(cst.Name, node.expression)
         if self._is_optional_type(expression):
             replacement_comparison = self._gen_comparison_to_none(
                 variable_name=expression.value, operator=cst.Is()
             )
             self.report(node, replacement=replacement_comparison)
Beispiel #4
0
class NotIsConditionTransformer(NoqaAwareTransformer):
    @m.leave(
        m.UnaryOperation(
            operator=m.Not(),
            expression=m.Comparison(
                comparisons=[m.ComparisonTarget(operator=m.Is())]),
        ))
    def replace_not_in_condition(
            self, _, updated_node: cst.UnaryOperation) -> cst.BaseExpression:
        comparison_node: cst.Comparison = cst.ensure_type(
            updated_node.expression, cst.Comparison)

        # TODO: Implement support for multiple consecutive 'not ... in B',
        # even if it does not make any sense in practice.
        return cst.Comparison(
            left=comparison_node.left,
            lpar=updated_node.lpar,
            rpar=updated_node.rpar,
            comparisons=[
                comparison_node.comparisons[0].with_changes(
                    operator=cst.IsNot())
            ],
        )
Beispiel #5
0
class ShedFixers(VisitorBasedCodemodCommand):
    """Fix a variety of small problems.

    Replaces `raise NotImplemented` with `raise NotImplementedError`,
    and converts always-failing assert statements to explicit `raise` statements.

    Also includes code closely modelled on pybetter's fixers, because it's
    considerably faster to run all transforms in a single pass if possible.
    """

    DESCRIPTION = "Fix a variety of style, performance, and correctness issues."

    @m.call_if_inside(m.Raise(exc=m.Name(value="NotImplemented")))
    def leave_Name(self, _, updated_node):  # noqa
        return updated_node.with_changes(value="NotImplementedError")

    def leave_Assert(self, _, updated_node):  # noqa
        test_code = cst.Module("").code_for_node(updated_node.test)
        try:
            test_literal = literal_eval(test_code)
        except Exception:
            return updated_node
        if test_literal:
            return cst.RemovalSentinel.REMOVE
        if updated_node.msg is None:
            return cst.Raise(cst.Name("AssertionError"))
        return cst.Raise(
            cst.Call(cst.Name("AssertionError"),
                     args=[cst.Arg(updated_node.msg)]))

    @m.leave(
        m.ComparisonTarget(comparator=oneof_names("None", "False", "True"),
                           operator=m.Equal()))
    def convert_none_cmp(self, _, updated_node):
        """Inspired by Pybetter."""
        return updated_node.with_changes(operator=cst.Is())

    @m.leave(
        m.UnaryOperation(
            operator=m.Not(),
            expression=m.Comparison(
                comparisons=[m.ComparisonTarget(operator=m.In())]),
        ))
    def replace_not_in_condition(self, _, updated_node):
        """Also inspired by Pybetter."""
        expr = cst.ensure_type(updated_node.expression, cst.Comparison)
        return cst.Comparison(
            left=expr.left,
            lpar=updated_node.lpar,
            rpar=updated_node.rpar,
            comparisons=[
                expr.comparisons[0].with_changes(operator=cst.NotIn())
            ],
        )

    @m.leave(
        m.Call(
            lpar=[m.AtLeastN(n=1, matcher=m.LeftParen())],
            rpar=[m.AtLeastN(n=1, matcher=m.RightParen())],
        ))
    def remove_pointless_parens_around_call(self, _, updated_node):
        # This is *probably* valid, but we might have e.g. a multi-line parenthesised
        # chain of attribute accesses ("fluent interface"), where we need the parens.
        noparens = updated_node.with_changes(lpar=[], rpar=[])
        try:
            compile(self.module.code_for_node(noparens), "<string>", "eval")
            return noparens
        except SyntaxError:
            return updated_node

    # The following methods fix https://pypi.org/project/flake8-comprehensions/

    @m.leave(m.Call(func=m.Name("list"), args=[m.Arg(m.GeneratorExp())]))
    def replace_generator_in_call_with_comprehension(self, _, updated_node):
        """Fix flake8-comprehensions C400-402 and 403-404.

        C400-402: Unnecessary generator - rewrite as a <list/set/dict> comprehension.
        Note that set and dict conversions are handled by pyupgrade!
        """
        return cst.ListComp(elt=updated_node.args[0].value.elt,
                            for_in=updated_node.args[0].value.for_in)

    @m.leave(
        m.Call(func=m.Name("list"), args=[m.Arg(m.ListComp(), star="")])
        | m.Call(func=m.Name("set"), args=[m.Arg(m.SetComp(), star="")])
        | m.Call(
            func=m.Name("list"),
            args=[m.Arg(m.Call(func=oneof_names("sorted", "list")), star="")],
        ))
    def replace_unnecessary_list_around_sorted(self, _, updated_node):
        """Fix flake8-comprehensions C411 and C413.

        Unnecessary <list/reversed> call around sorted().

        Also covers C411 Unnecessary list call around list comprehension
        for lists and sets.
        """
        return updated_node.args[0].value

    @m.leave(
        m.Call(
            func=m.Name("reversed"),
            args=[m.Arg(m.Call(func=m.Name("sorted")), star="")],
        ))
    def replace_unnecessary_reversed_around_sorted(self, _, updated_node):
        """Fix flake8-comprehensions C413.

        Unnecessary reversed call around sorted().
        """
        call = updated_node.args[0].value
        args = list(call.args)
        for i, arg in enumerate(args):
            if m.matches(arg.keyword, m.Name("reverse")):
                try:
                    val = bool(
                        literal_eval(self.module.code_for_node(arg.value)))
                except Exception:
                    args[i] = arg.with_changes(
                        value=cst.UnaryOperation(cst.Not(), arg.value))
                else:
                    if not val:
                        args[i] = arg.with_changes(value=cst.Name("True"))
                    else:
                        del args[i]
                        args[i - 1] = remove_trailing_comma(args[i - 1])
                break
        else:
            args.append(
                cst.Arg(keyword=cst.Name("reverse"), value=cst.Name("True")))
        return call.with_changes(args=args)

    _sets = oneof_names("set", "frozenset")
    _seqs = oneof_names("list", "reversed", "sorted", "tuple")

    @m.leave(
        m.Call(func=_sets, args=[m.Arg(m.Call(func=_sets | _seqs), star="")])
        | m.Call(
            func=oneof_names("list", "tuple"),
            args=[m.Arg(m.Call(func=oneof_names("list", "tuple")), star="")],
        )
        | m.Call(
            func=m.Name("sorted"),
            args=[m.Arg(m.Call(func=_seqs), star=""),
                  m.ZeroOrMore()],
        ))
    def replace_unnecessary_nested_calls(self, _, updated_node):
        """Fix flake8-comprehensions C414.

        Unnecessary <list/reversed/sorted/tuple> call within <list/set/sorted/tuple>()..
        """
        return updated_node.with_changes(
            args=[cst.Arg(updated_node.args[0].value.args[0].value)] +
            list(updated_node.args[1:]), )

    @m.leave(
        m.Call(
            func=oneof_names("reversed", "set", "sorted"),
            args=[
                m.Arg(m.Subscript(slice=[m.SubscriptElement(ALL_ELEMS_SLICE)]))
            ],
        ))
    def replace_unnecessary_subscript_reversal(self, _, updated_node):
        """Fix flake8-comprehensions C415.

        Unnecessary subscript reversal of iterable within <reversed/set/sorted>().
        """
        return updated_node.with_changes(
            args=[cst.Arg(updated_node.args[0].value.value)], )

    @m.leave(
        multi(
            m.ListComp,
            m.SetComp,
            elt=m.Name(),
            for_in=m.CompFor(target=m.Name(),
                             ifs=[],
                             inner_for_in=None,
                             asynchronous=None),
        ))
    def replace_unnecessary_listcomp_or_setcomp(self, _, updated_node):
        """Fix flake8-comprehensions C416.

        Unnecessary <list/set> comprehension - rewrite using <list/set>().
        """
        if updated_node.elt.value == updated_node.for_in.target.value:
            func = cst.Name(
                "list" if isinstance(updated_node, cst.ListComp) else "set")
            return cst.Call(func=func,
                            args=[cst.Arg(updated_node.for_in.iter)])
        return updated_node

    @m.leave(m.Subscript(oneof_names("Union", "Literal")))
    def reorder_union_literal_contents_none_last(self, _, updated_node):
        subscript = list(updated_node.slice)
        try:
            subscript.sort(key=lambda elt: elt.slice.value.value == "None")
            subscript[-1] = remove_trailing_comma(subscript[-1])
            return updated_node.with_changes(slice=subscript)
        except Exception:  # Single-element literals are not slices, etc.
            return updated_node

    @m.call_if_inside(m.Annotation(annotation=m.BinaryOperation()))
    @m.leave(
        m.BinaryOperation(
            left=m.Name("None") | m.BinaryOperation(),
            operator=m.BitOr(),
            right=m.DoNotCare(),
        ))
    def reorder_union_operator_contents_none_last(self, _, updated_node):
        def _has_none(node):
            if m.matches(node, m.Name("None")):
                return True
            elif m.matches(node, m.BinaryOperation()):
                return _has_none(node.left) or _has_none(node.right)
            else:
                return False

        node_left = updated_node.left
        if _has_none(node_left):
            return updated_node.with_changes(left=updated_node.right,
                                             right=node_left)
        else:
            return updated_node

    @m.leave(m.Subscript(value=m.Name("Literal")))
    def flatten_literal_subscript(self, _, updated_node):
        new_slice = []
        for item in updated_node.slice:
            if m.matches(item.slice.value, m.Subscript(m.Name("Literal"))):
                new_slice += item.slice.value.slice
            else:
                new_slice.append(item)
        return updated_node.with_changes(slice=new_slice)

    @m.leave(m.Subscript(value=m.Name("Union")))
    def flatten_union_subscript(self, _, updated_node):
        new_slice = []
        has_none = False
        for item in updated_node.slice:
            if m.matches(item.slice.value, m.Subscript(m.Name("Optional"))):
                new_slice += item.slice.value.slice  # peel off "Optional"
                has_none = True
            elif m.matches(item.slice.value,
                           m.Subscript(m.Name("Union"))) and m.matches(
                               updated_node.value, item.slice.value.value):
                new_slice += item.slice.value.slice  # peel off "Union" or "Literal"
            elif m.matches(item.slice.value, m.Name("None")):
                has_none = True
            else:
                new_slice.append(item)
        if has_none:
            new_slice.append(
                cst.SubscriptElement(slice=cst.Index(cst.Name("None"))))
        return updated_node.with_changes(slice=new_slice)

    @m.leave(m.Else(m.IndentedBlock([m.SimpleStatementLine([m.Pass()])])))
    def discard_empty_else_blocks(self, _, updated_node):
        # An `else: pass` block can always simply be discarded, and libcst ensures
        # that an Else node can only ever occur attached to an If, While, For, or Try
        # node; in each case `None` is the valid way to represent "no else block".
        if m.findall(updated_node, m.Comment()):
            return updated_node  # If there are any comments, keep the node
        return cst.RemoveFromParent()

    @m.leave(
        m.Lambda(params=m.MatchIfTrue(lambda node: (
            node.star_kwarg is None and not node.kwonly_params and not node.
            posonly_params and isinstance(node.star_arg, cst.MaybeSentinel) and
            all(param.default is None for param in node.params)))))
    def remove_lambda_indirection(self, _, updated_node):
        same_args = [
            m.Arg(m.Name(param.name.value), star="", keyword=None)
            for param in updated_node.params.params
        ]
        if m.matches(updated_node.body, m.Call(args=same_args)):
            return cst.ensure_type(updated_node.body, cst.Call).func
        return updated_node

    @m.leave(
        m.BooleanOperation(
            left=m.Call(m.Name("isinstance"), [m.Arg(), m.Arg()]),
            operator=m.Or(),
            right=m.Call(m.Name("isinstance"), [m.Arg(), m.Arg()]),
        ))
    def collapse_isinstance_checks(self, _, updated_node):
        left_target, left_type = updated_node.left.args
        right_target, right_type = updated_node.right.args
        if left_target.deep_equals(right_target):
            merged_type = cst.Arg(
                cst.Tuple([
                    cst.Element(left_type.value),
                    cst.Element(right_type.value)
                ]))
            return updated_node.left.with_changes(
                args=[left_target, merged_type])
        return updated_node
Beispiel #6
0
def remove_trailing_comma(node):
    # Remove the comma from this node, *unless* it's already a comma node with comments
    if node.comma is cst.MaybeSentinel.DEFAULT or m.findall(node, m.Comment()):
        return node
    return node.with_changes(comma=cst.MaybeSentinel.DEFAULT)


MATCH_NONE = m.MatchIfTrue(lambda x: x is None)
ALL_ELEMS_SLICE = m.Slice(
    lower=MATCH_NONE | m.Name("None"),
    upper=MATCH_NONE | m.Name("None"),
    step=MATCH_NONE
    | m.Name("None")
    | m.Integer("1")
    | m.UnaryOperation(m.Minus(), m.Integer("1")),
)


class ShedFixers(VisitorBasedCodemodCommand):
    """Fix a variety of small problems.

    Replaces `raise NotImplemented` with `raise NotImplementedError`,
    and converts always-failing assert statements to explicit `raise` statements.

    Also includes code closely modelled on pybetter's fixers, because it's
    considerably faster to run all transforms in a single pass if possible.
    """

    DESCRIPTION = "Fix a variety of style, performance, and correctness issues."
Beispiel #7
0
    def obf_universal(self, node: cst.CSTNode, *types):

        if m.matches(node, m.Name()):
            types = ('a', 'ca', 'v', 'cv') if not types else types
            node = cst.ensure_type(node, cst.Name)
            if self.can_rename(node.value, *types):
                node = self.get_new_cst_name(node)

        elif m.matches(node, m.NameItem()):
            node = cst.ensure_type(node, cst.NameItem)
            node = node.with_changes(name=self.obf_universal(node.name))

        elif m.matches(node, m.Call()):

            node = cst.ensure_type(node, cst.Call)
            if self.change_methods or self.change_functions:
                node = self.new_obf_function_name(node)
            if self.change_arguments or self.change_method_arguments:
                node = self.obf_function_args(node)

        elif m.matches(node, m.Attribute()):
            node = cst.ensure_type(node, cst.Attribute)
            value = node.value
            attr = node.attr

            self.obf_universal(value)
            self.obf_universal(attr)

        elif m.matches(node, m.AssignTarget()):
            node = cst.ensure_type(node, cst.AssignTarget)
            node = node.with_changes(target=self.obf_universal(node.target))

        elif m.matches(node, m.List() | m.Tuple()):
            node = cst.ensure_type(node, cst.List) if m.matches(
                node, m.List()) else cst.ensure_type(node, cst.Tuple)
            new_elements = []
            for el in node.elements:
                new_elements.append(self.obf_universal(el))
            node = node.with_changes(elements=new_elements)
        elif m.matches(node, m.Subscript()):
            node = cst.ensure_type(node, cst.Subscript)
            new_slice = []
            for el in node.slice:
                new_slice.append(
                    el.with_changes(slice=self.obf_slice(el.slice)))
            node = node.with_changes(slice=new_slice)
            node = node.with_changes(value=self.obf_universal(node.value))
        elif m.matches(node, m.Element()):
            node = cst.ensure_type(node, cst.Element)
            node = node.with_changes(value=self.obf_universal(node.value))

        elif m.matches(node, m.Dict()):
            node = cst.ensure_type(node, cst.Dict)
            new_elements = []
            for el in node.elements:
                new_elements.append(self.obf_universal(el))
            node = node.with_changes(elements=new_elements)
        elif m.matches(node, m.DictElement()):
            node = cst.ensure_type(node, cst.DictElement)
            new_key = self.obf_universal(node.key)
            new_val = self.obf_universal(node.value)
            node = node.with_changes(key=new_key, value=new_val)
        elif m.matches(node, m.StarredDictElement()):
            node = cst.ensure_type(node, cst.StarredDictElement)
            node = node.with_changes(value=self.obf_universal(node.value))

        elif m.matches(node, m.If() | m.While()):
            node = cst.ensure_type(node, cst.IfExp) if m.matches(
                node, cst.If
                | cst.IfExp) else cst.ensure_type(node, cst.While)
            node = node.with_changes(test=self.obf_universal(node.test))
        elif m.matches(node, m.IfExp()):
            node = cst.ensure_type(node, cst.IfExp)
            node = node.with_changes(body=self.obf_universal(node.body))
            node = node.with_changes(test=self.obf_universal(node.test))
            node = node.with_changes(orelse=self.obf_universal(node.orelse))

        elif m.matches(node, m.Comparison()):
            node = cst.ensure_type(node, cst.Comparison)
            new_compars = []
            for target in node.comparisons:
                new_compars.append(self.obf_universal(target))

            node = node.with_changes(left=self.obf_universal(node.left))
            node = node.with_changes(comparisons=new_compars)
        elif m.matches(node, m.ComparisonTarget()):
            node = cst.ensure_type(node, cst.ComparisonTarget)
            node = node.with_changes(
                comparator=self.obf_universal(node.comparator))

        elif m.matches(node, m.FormattedString()):
            node = cst.ensure_type(node, cst.FormattedString)
            new_parts = []
            for part in node.parts:
                new_parts.append(self.obf_universal(part))
            node = node.with_changes(parts=new_parts)
        elif m.matches(node, m.FormattedStringExpression()):
            node = cst.ensure_type(node, cst.FormattedStringExpression)
            node = node.with_changes(
                expression=self.obf_universal(node.expression))

        elif m.matches(node, m.BinaryOperation() | m.BooleanOperation()):
            node = cst.ensure_type(node, cst.BinaryOperation) if m.matches(
                node, m.BinaryOperation()) else cst.ensure_type(
                    node, cst.BooleanOperation)
            node = node.with_changes(left=self.obf_universal(node.left),
                                     right=self.obf_universal(node.right))
        elif m.matches(node, m.UnaryOperation()):
            node = cst.ensure_type(node, cst.UnaryOperation)
            node = node.with_changes(
                expression=self.obf_universal(node.expression))

        elif m.matches(node, m.ListComp()):
            node = cst.ensure_type(node, cst.ListComp)
            node = node.with_changes(elt=self.obf_universal(node.elt))
            node = node.with_changes(for_in=self.obf_universal(node.for_in))

        elif m.matches(node, m.DictComp()):
            node = cst.ensure_type(node, cst.DictComp)
            node = node.with_changes(key=self.obf_universal(node.key))
            node = node.with_changes(value=self.obf_universal(node.value))
            node = node.with_changes(for_in=self.obf_universal(node.for_in))

        elif m.matches(node, m.CompFor()):
            node = cst.ensure_type(node, cst.CompFor)
            new_ifs = []

            node = node.with_changes(target=self.obf_universal(node.target))
            node = node.with_changes(iter=self.obf_universal(node.iter))
            for el in node.ifs:
                new_ifs.append(self.obf_universal(el))
            node = node.with_changes(ifs=new_ifs)
        elif m.matches(node, m.CompIf()):
            node = cst.ensure_type(node, cst.CompIf)
            node = node.with_changes(test=self.obf_universal(node.test))

        elif m.matches(node, m.Integer() | m.Float() | m.SimpleString()):
            pass

        else:
            pass
            # print(node)

        return node
Beispiel #8
0
    def visit_Call(self, node: cst.Call) -> None:
        # `self.assertTrue(x is not None)` -> `self.assertIsNotNone(x)`
        if m.matches(
                node,
                m.Call(
                    func=m.Attribute(value=m.Name("self"),
                                     attr=m.Name("assertTrue")),
                    args=[
                        m.Arg(
                            m.Comparison(comparisons=[
                                m.ComparisonTarget(m.IsNot(),
                                                   comparator=m.Name("None"))
                            ]))
                    ],
                ),
        ):
            new_call = node.with_changes(
                func=cst.Attribute(value=cst.Name("self"),
                                   attr=cst.Name("assertIsNotNone")),
                args=[
                    cst.Arg(
                        ensure_type(node.args[0].value, cst.Comparison).left)
                ],
            )
            self.report(node, replacement=new_call)

        # `self.assertTrue(not x is None)` -> `self.assertIsNotNone(x)`
        elif m.matches(
                node,
                m.Call(
                    func=m.Attribute(value=m.Name("self"),
                                     attr=m.Name("assertTrue")),
                    args=[
                        m.Arg(value=m.UnaryOperation(
                            operator=m.Not(),
                            expression=m.Comparison(comparisons=[
                                m.ComparisonTarget(m.Is(),
                                                   comparator=m.Name("None"))
                            ]),
                        ))
                    ],
                ),
        ):

            new_call = node.with_changes(
                func=cst.Attribute(value=cst.Name("self"),
                                   attr=cst.Name("assertIsNotNone")),
                args=[
                    cst.Arg(
                        ensure_type(
                            ensure_type(node.args[0].value,
                                        cst.UnaryOperation).expression,
                            cst.Comparison,
                        ).left)
                ],
            )
            self.report(node, replacement=new_call)
        # `self.assertFalse(x is None)` -> `self.assertIsNotNone(x)`
        elif m.matches(
                node,
                m.Call(
                    func=m.Attribute(value=m.Name("self"),
                                     attr=m.Name("assertFalse")),
                    args=[
                        m.Arg(
                            m.Comparison(comparisons=[
                                m.ComparisonTarget(m.Is(),
                                                   comparator=m.Name("None"))
                            ]))
                    ],
                ),
        ):
            new_call = node.with_changes(
                func=cst.Attribute(value=cst.Name("self"),
                                   attr=cst.Name("assertIsNotNone")),
                args=[
                    cst.Arg(
                        ensure_type(node.args[0].value, cst.Comparison).left)
                ],
            )
            self.report(node, replacement=new_call)
        # `self.assertTrue(x is None)` -> `self.assertIsNotNone(x))
        elif m.matches(
                node,
                m.Call(
                    func=m.Attribute(value=m.Name("self"),
                                     attr=m.Name("assertTrue")),
                    args=[
                        m.Arg(
                            m.Comparison(comparisons=[
                                m.ComparisonTarget(m.Is(),
                                                   comparator=m.Name("None"))
                            ]))
                    ],
                ),
        ):
            new_call = node.with_changes(
                func=cst.Attribute(value=cst.Name("self"),
                                   attr=cst.Name("assertIsNone")),
                args=[
                    cst.Arg(
                        ensure_type(node.args[0].value, cst.Comparison).left)
                ],
            )
            self.report(node, replacement=new_call)

        # `self.assertFalse(x is not None)` -> `self.assertIsNone(x)`
        elif m.matches(
                node,
                m.Call(
                    func=m.Attribute(value=m.Name("self"),
                                     attr=m.Name("assertFalse")),
                    args=[
                        m.Arg(
                            m.Comparison(comparisons=[
                                m.ComparisonTarget(m.IsNot(),
                                                   comparator=m.Name("None"))
                            ]))
                    ],
                ),
        ):
            new_call = node.with_changes(
                func=cst.Attribute(value=cst.Name("self"),
                                   attr=cst.Name("assertIsNone")),
                args=[
                    cst.Arg(
                        ensure_type(node.args[0].value, cst.Comparison).left)
                ],
            )
            self.report(node, replacement=new_call)
        # `self.assertFalse(not x is None)` -> `self.assertIsNone(x)`
        elif m.matches(
                node,
                m.Call(
                    func=m.Attribute(value=m.Name("self"),
                                     attr=m.Name("assertFalse")),
                    args=[
                        m.Arg(value=m.UnaryOperation(
                            operator=m.Not(),
                            expression=m.Comparison(comparisons=[
                                m.ComparisonTarget(m.Is(),
                                                   comparator=m.Name("None"))
                            ]),
                        ))
                    ],
                ),
        ):

            new_call = node.with_changes(
                func=cst.Attribute(value=cst.Name("self"),
                                   attr=cst.Name("assertIsNone")),
                args=[
                    cst.Arg(
                        ensure_type(
                            ensure_type(node.args[0].value,
                                        cst.UnaryOperation).expression,
                            cst.Comparison,
                        ).left)
                ],
            )
            self.report(node, replacement=new_call)
Beispiel #9
0
    def visit_Call(self, node: cst.Call) -> None:
        # Todo: Make use of single extract instead of having several
        # if else statemenets to make the code more robust and readable.
        if m.matches(
                node,
                m.Call(
                    func=m.Attribute(value=m.Name("self"),
                                     attr=m.Name("assertTrue")),
                    args=[
                        m.Arg(
                            m.Comparison(comparisons=[
                                m.ComparisonTarget(operator=m.In())
                            ]))
                    ],
                ),
        ):
            # self.assertTrue(a in b) -> self.assertIn(a, b)
            new_call = node.with_changes(
                func=cst.Attribute(value=cst.Name("self"),
                                   attr=cst.Name("assertIn")),
                args=[
                    cst.Arg(
                        ensure_type(node.args[0].value, cst.Comparison).left),
                    cst.Arg(
                        ensure_type(node.args[0].value,
                                    cst.Comparison).comparisons[0].comparator),
                ],
            )
            self.report(node, replacement=new_call)
        else:
            # ... -> self.assertNotIn(a, b)
            matched, arg1, arg2 = False, None, None
            if m.matches(
                    node,
                    m.Call(
                        func=m.Attribute(value=m.Name("self"),
                                         attr=m.Name("assertTrue")),
                        args=[
                            m.Arg(
                                m.UnaryOperation(
                                    operator=m.Not(),
                                    expression=m.Comparison(comparisons=[
                                        m.ComparisonTarget(operator=m.In())
                                    ]),
                                ))
                        ],
                    ),
            ):
                # self.assertTrue(not a in b) -> self.assertNotIn(a, b)
                matched = True
                arg1 = cst.Arg(
                    ensure_type(
                        ensure_type(node.args[0].value,
                                    cst.UnaryOperation).expression,
                        cst.Comparison,
                    ).left)
                arg2 = cst.Arg(
                    ensure_type(
                        ensure_type(node.args[0].value,
                                    cst.UnaryOperation).expression,
                        cst.Comparison,
                    ).comparisons[0].comparator)
            elif m.matches(
                    node,
                    m.Call(
                        func=m.Attribute(value=m.Name("self"),
                                         attr=m.Name("assertTrue")),
                        args=[
                            m.Arg(
                                m.Comparison(comparisons=[
                                    m.ComparisonTarget(m.NotIn())
                                ]))
                        ],
                    ),
            ):
                # self.assertTrue(a not in b) -> self.assertNotIn(a, b)
                matched = True
                arg1 = cst.Arg(
                    ensure_type(node.args[0].value, cst.Comparison).left)
                arg2 = cst.Arg(
                    ensure_type(node.args[0].value,
                                cst.Comparison).comparisons[0].comparator)
            elif m.matches(
                    node,
                    m.Call(
                        func=m.Attribute(value=m.Name("self"),
                                         attr=m.Name("assertFalse")),
                        args=[
                            m.Arg(
                                m.Comparison(
                                    comparisons=[m.ComparisonTarget(m.In())]))
                        ],
                    ),
            ):
                # self.assertFalse(a in b) -> self.assertNotIn(a, b)
                matched = True
                arg1 = cst.Arg(
                    ensure_type(node.args[0].value, cst.Comparison).left)
                arg2 = cst.Arg(
                    ensure_type(node.args[0].value,
                                cst.Comparison).comparisons[0].comparator)

            if matched:
                new_call = node.with_changes(
                    func=cst.Attribute(value=cst.Name("self"),
                                       attr=cst.Name("assertNotIn")),
                    args=[arg1, arg2],
                )
                self.report(node, replacement=new_call)
    def visit_Call(self, node: cst.Call) -> None:
        match_compare_is_none = m.ComparisonTarget(
            m.SaveMatchedNode(
                m.OneOf(m.Is(), m.IsNot()),
                "comparison_type",
            ),
            comparator=m.Name("None"),
        )
        result = m.extract(
            node,
            m.Call(
                func=m.Attribute(
                    value=m.Name("self"),
                    attr=m.SaveMatchedNode(
                        m.OneOf(m.Name("assertTrue"), m.Name("assertFalse")),
                        "assertion_name",
                    ),
                ),
                args=[
                    m.Arg(
                        m.SaveMatchedNode(
                            m.OneOf(
                                m.Comparison(
                                    comparisons=[match_compare_is_none]),
                                m.UnaryOperation(
                                    operator=m.Not(),
                                    expression=m.Comparison(
                                        comparisons=[match_compare_is_none]),
                                ),
                            ),
                            "argument",
                        ))
                ],
            ),
        )

        if result:
            assertion_name = result["assertion_name"]
            if isinstance(assertion_name, Sequence):
                assertion_name = assertion_name[0]

            argument = result["argument"]
            if isinstance(argument, Sequence):
                argument = argument[0]

            comparison_type = result["comparison_type"]
            if isinstance(comparison_type, Sequence):
                comparison_type = comparison_type[0]

            if m.matches(argument, m.Comparison()):
                assertion_argument = ensure_type(argument, cst.Comparison).left
            else:
                assertion_argument = ensure_type(
                    ensure_type(argument, cst.UnaryOperation).expression,
                    cst.Comparison).left

            negations_seen = 0
            if m.matches(assertion_name, m.Name("assertFalse")):
                negations_seen += 1
            if m.matches(argument, m.UnaryOperation()):
                negations_seen += 1
            if m.matches(comparison_type, m.IsNot()):
                negations_seen += 1

            new_attr = "assertIsNone" if negations_seen % 2 == 0 else "assertIsNotNone"
            new_call = node.with_changes(
                func=cst.Attribute(value=cst.Name("self"),
                                   attr=cst.Name(new_attr)),
                args=[cst.Arg(assertion_argument)],
            )

            if new_call is not node:
                self.report(node, replacement=new_call)