Пример #1
0
def newBinOp(o):
    if type(o) == type(_ast.Add()):
        return _ast.Sub()
    elif type(o) == type(_ast.Sub()):
        return _ast.Add()#elif type(o) == type(_ast.)
    elif type(o) == type(_ast.Mult()):
        return _ast.FloorDiv()
    elif type(o) == type(_ast.FloorDiv()):
        return _ast.Mult()
    else:
        return o
Пример #2
0
 def test_node_identity(self):
     import _ast as ast
     n1 = ast.Num(1)
     n3 = ast.Num(3)
     addop = ast.Add()
     x = ast.BinOp(n1, addop, n3)
     assert x.left == n1
     assert x.op == addop
     assert x.right == n3
Пример #3
0
 def __add__(self, other):
     if isinstance(other, Variable):
         other = other.value
     if isinstance(self.value, _ast.AST):
         return _ast.BinOp(self.value, _ast.Add(),
                           ast_magic.wrap_value(other))
         # self.value=_ast.BinOp(self.value,_ast.Add(), ast_magic.wrap_value(other))
     else:
         return self.value + other
Пример #4
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def Add():
    return _ast.Add()
Пример #5
0
 def add(self, items):
     (left, right) = items
     return _ast.BinOp(left=left, op=_ast.Add(), right=right)
Пример #6
0
def _cfa(body, state, on_gen):
    assert isinstance(on_gen, list)
    for c in on_gen:
        assert callable(c)

    cfg = state.cfg

    def make_connect(cur_bid):
        assert isinstance(cur_bid, int)

        def inner(new_bid):
            assert isinstance(new_bid, int)
            state.connect([cur_bid], [new_bid])

        return inner

    def push_block(block):
        block_id = len(cfg.blocks)
        assert block_id not in cfg.blocks
        cfg.blocks[block_id] = block
        for c in on_gen:
            c(block_id)
        return block_id

    cur_block = []

    for b in body:
        if REDUCE_FORS_TO_WHILES and isinstance(b, _ast.For):
            if isinstance(b.iter, _ast.Call) and isinstance(
                    b.iter.func,
                    _ast.Name) and b.iter.func.id in ("range", "xrange"):
                if not b.iter.keywords and not b.iter.starargs and not b.iter.kwargs:
                    end_var = "__wfend_%d_%d_" % (b.lineno, b.col_offset)
                    iter_var = "__wfiter_%d_%d_" % (b.lineno, b.col_offset)
                    if len(b.iter.args) in (1, 2):
                        if len(b.iter.args) == 1:
                            start = _ast.Num(0)
                            end = b.iter.args[0]
                        elif len(b.iter.args) == 2:
                            start = b.iter.args[0]
                            end = b.iter.args[1]
                        else:
                            start = b.iter.args[0]
                            end = b.iter.args[1]
                        cur_block.append(
                            _ast.Assign([
                                _ast.Name(
                                    iter_var, _ast.Store(), not_real=True)
                            ],
                                        start,
                                        lineno=b.lineno,
                                        col_offset=b.col_offset,
                                        not_real=True))
                        cur_block.append(
                            _ast.Assign([
                                _ast.Name(end_var, _ast.Store(), not_real=True)
                            ],
                                        end,
                                        lineno=b.lineno,
                                        col_offset=b.col_offset,
                                        not_real=True))

                        body = [
                            _ast.Assign([b.target],
                                        _ast.Name(iter_var,
                                                  _ast.Load(),
                                                  not_real=True),
                                        lineno=b.lineno,
                                        col_offset=b.col_offset,
                                        not_real=True),
                            _ast.Assign([
                                _ast.Name(
                                    iter_var, _ast.Store(), not_real=True)
                            ],
                                        _ast.BinOp(
                                            _ast.Name(iter_var,
                                                      _ast.Load(),
                                                      not_real=True),
                                            _ast.Add(), _ast.Num(1)),
                                        lineno=b.lineno,
                                        col_offset=b.col_offset,
                                        not_real=True)
                        ] + b.body
                        b = _ast.While(_ast.Compare(
                            _ast.Name(iter_var, _ast.Load(),
                                      not_real=True), [_ast.Lt()],
                            [_ast.Name(end_var, _ast.Load(), not_real=True)],
                            lineno=b.lineno,
                            col_offset=b.col_offset,
                            not_real=True),
                                       body,
                                       b.orelse,
                                       not_real=True)

        if isinstance(b, (
                _ast.Assign,
                _ast.AugAssign,
                _ast.ClassDef,
                _ast.Delete,
                _ast.Exec,
                _ast.Expr,
                _ast.FunctionDef,
                _ast.Global,
                _ast.Import,
                _ast.ImportFrom,
                _ast.Print,
                _ast.Pass,
        )):
            cur_block.append(b)
        elif isinstance(b, _ast.Assert):
            cur_block.append(b)
            if isinstance(b.test, _ast.Call) and isinstance(
                    b.test.func, _ast.Name
            ) and b.test.func.id == "isinstance" and isinstance(
                    b.test.args[0], _ast.Name) and isinstance(
                        b.test.args[1], _ast.Name):
                varname = b.test.args[0].id
                cast = _ast.Call(_ast.Name(
                    "__cast__", _ast.Load(), not_real=True, **pos(b)), [
                        _ast.Name(
                            varname, _ast.Store(), not_real=True, **pos(b)),
                        b.test.args[1]
                    ], [],
                                 None,
                                 None,
                                 not_real=True,
                                 **pos(b))
                assign = _ast.Assign([
                    _ast.Name(varname, _ast.Store(), not_real=True, **pos(b))
                ],
                                     cast,
                                     not_real=True,
                                     lineno=b.lineno,
                                     col_offset=b.col_offset)
                cur_block.append(assign)
        elif isinstance(b, (_ast.Break, _ast.Continue)):
            f = state.add_break if isinstance(
                b, _ast.Break) else state.add_continue
            if cur_block:
                j = Jump()
                cur_block.append(j)
                block_id = push_block(cur_block)
                f(j.set_dest)
                f(make_connect(block_id))
            else:
                for c in on_gen:
                    f(c)
            return []
        elif isinstance(b, _ast.If):
            br = Branch(b.test, lineno=b.lineno)
            cur_block.append(br)
            next_block = push_block(cur_block)
            on_gen = None  # make sure this doesn't get used
            cur_block = []

            gen_true = [br.set_true, make_connect(next_block)]
            gen_false = [br.set_false, make_connect(next_block)]
            if ENFORCE_NO_MULTIMULTI:
                on_gen = gen_true
                j1 = Jump()
                gen_true = [make_connect(push_block([j1])), j1.set_dest]

                on_gen = gen_false
                j2 = Jump()
                gen_false = [make_connect(push_block([j2])), j2.set_dest]

                on_gen = None

            assert b.body
            body = b.body
            if isinstance(b.test, _ast.Call) and isinstance(
                    b.test.func, _ast.Name
            ) and b.test.func.id == "isinstance" and isinstance(
                    b.test.args[0], _ast.Name) and isinstance(
                        b.test.args[1], _ast.Name):
                varname = b.test.args[0].id
                cast = _ast.Call(_ast.Name(
                    "__cast__", _ast.Load(), not_real=True, **pos(b)), [
                        _ast.Name(
                            varname, _ast.Store(), not_real=True, **pos(b)),
                        b.test.args[1]
                    ], [],
                                 None,
                                 None,
                                 not_real=True,
                                 **pos(b))
                assign = _ast.Assign([
                    _ast.Name(varname, _ast.Store(), not_real=True, **pos(b))
                ],
                                     cast,
                                     not_real=True,
                                     lineno=b.lineno,
                                     col_offset=b.col_offset)
                body = [assign] + body
            if ADD_IF_ASSERTS:
                body = [_ast.Assert(b.test, None, not_real=True, **pos(b))
                        ] + body
            ending_gen = _cfa(body, state, gen_true)
            if b.orelse:
                ending_gen += _cfa(b.orelse, state, gen_false)
            else:
                ending_gen += gen_false
            on_gen = ending_gen

            if not on_gen and PRUNE_UNREACHABLE_BLOCKS:
                return []
        elif isinstance(b, _ast.TryExcept):
            j = Jump()
            cur_block.append(j)
            next_block = push_block(cur_block)
            on_gen = [j.set_dest, make_connect(next_block)]
            cur_block = []

            on_gen = _cfa(b.body, state, on_gen)

            # Set this to evaluate a string to try to defeat simple flow analysis
            br = Branch(_ast.Str("nonzero"))
            next_block = push_block([br])

            on_except = [br.set_false, make_connect(next_block)]
            on_fine = [br.set_true, make_connect(next_block)]

            assert len(b.handlers) >= 1
            # for handler in b.handlers:
            # on_except = _cfa(b.handlers[0].body, state, on_except)

            if b.orelse:
                on_fine = _cfa(b.orelse, state, on_fine)

            if ENFORCE_NO_MULTIMULTI:
                j = Jump()
                on_gen = on_fine
                next_block = push_block([j])
                on_fine = [j.set_dest, make_connect(next_block)]

                j = Jump()
                on_gen = on_except
                next_block = push_block([j])
                on_except = [j.set_dest, make_connect(next_block)]

            on_gen = on_fine + on_except
            cur_block = []
        elif isinstance(b, _ast.TryFinally):
            j = Jump()
            cur_block.append(j)
            next_block = push_block(cur_block)
            on_gen = [j.set_dest, make_connect(next_block)]
            cur_block = []

            on_gen = _cfa(b.body, state, on_gen)
            on_gen = _cfa(b.finalbody, state, on_gen)
        elif isinstance(b, _ast.While):
            # This could also be architected as having no extra block and having two jump statements, but I don't like that
            if cur_block:
                j = Jump()
                cur_block.append(j)
                on_gen = [make_connect(push_block(cur_block)), j.set_dest]
                cur_block = []

            always_true = False
            always_false = False
            if isinstance(b.test, _ast.Name):
                if b.test.id == "True":
                    always_true = True
                elif b.test.id == "False":
                    always_false = True
            elif isinstance(b.test, _ast.Num):
                if b.test.n:
                    always_true = True
                else:
                    always_false = True

            if always_true:
                br = Jump()
                on_true = br.set_dest
            elif always_false:
                br = Jump()
                on_false = br.set_dest
            else:
                br = Branch(b.test)
                on_true = br.set_true
                on_false = br.set_false
            init_id = push_block([br])
            on_gen = None
            assert cur_block == []  # just checking

            if not always_false:
                gen_true = [on_true, make_connect(init_id)]
            if not always_true:
                gen_false = [on_false, make_connect(init_id)]
            if ENFORCE_NO_MULTIMULTI:
                if not always_false:
                    on_gen = gen_true
                    j1 = Jump()
                    gen_true = [make_connect(push_block([j1])), j1.set_dest]

                if not always_true:
                    on_gen = gen_false
                    j2 = Jump()
                    gen_false = [make_connect(push_block([j2])), j2.set_dest]

                on_gen = None

            ending_gen = []
            if not always_false:
                state.push_loop()
                assert b.body
                loop_ending_gen = _cfa(b.body, state, gen_true)
                loop_ending_gen += state.get_continues()
                for c in loop_ending_gen:
                    c(init_id)
                ending_gen = state.get_breaks()
                state.pop_loop()

            if not always_true:
                if b.orelse:
                    ending_gen += _cfa(b.orelse, state, gen_false)
                else:
                    ending_gen += gen_false

            on_gen = ending_gen
            if not on_gen and PRUNE_UNREACHABLE_BLOCKS:
                return []
        elif isinstance(b, _ast.For):
            iter_func = _ast.Attribute(b.iter,
                                       "__iter__",
                                       _ast.Load(),
                                       not_real=True,
                                       lineno=b.lineno,
                                       col_offset=b.col_offset)
            iter_call = _ast.Call(iter_func, [], [],
                                  None,
                                  None,
                                  not_real=True,
                                  lineno=b.lineno,
                                  col_offset=b.col_offset)
            # iter_var = _make_temp_name()
            iter_var = "__foriter_%d_%d_" % (b.lineno, b.col_offset)
            iter_assign = _ast.Assign(
                [_ast.Name(iter_var, _ast.Store(), not_real=True, **pos(b))],
                iter_call,
                not_real=True,
                lineno=b.lineno,
                col_offset=b.col_offset)
            cur_block.append(iter_assign)

            j = Jump()
            cur_block.append(j)
            on_gen = [make_connect(push_block(cur_block)), j.set_dest]
            cur_block = []

            br = Branch(
                HasNext(
                    _ast.Name(iter_var, _ast.Load(), not_real=True, **pos(b)),
                    **pos(b)), **pos(b))
            init_id = push_block([br])
            on_gen = None
            assert cur_block == []  # just checking

            gen_true = [br.set_true, make_connect(init_id)]
            gen_false = [br.set_false, make_connect(init_id)]
            if ENFORCE_NO_MULTIMULTI:
                on_gen = gen_true
                j1 = Jump()
                gen_true = [make_connect(push_block([j1])), j1.set_dest]

                on_gen = gen_false
                j2 = Jump()
                gen_false = [make_connect(push_block([j2])), j2.set_dest]

                on_gen = None

            ending_gen = []

            state.push_loop()

            next_func = _ast.Attribute(_ast.Name(iter_var,
                                                 _ast.Load(),
                                                 not_real=True,
                                                 **pos(b)),
                                       "next",
                                       _ast.Load(),
                                       not_real=True,
                                       lineno=b.lineno,
                                       col_offset=b.col_offset)
            next = _ast.Call(next_func, [], [],
                             None,
                             None,
                             not_real=True,
                             lineno=b.lineno,
                             col_offset=b.col_offset)
            next_assign = _ast.Assign([b.target],
                                      next,
                                      not_real=True,
                                      lineno=b.lineno,
                                      col_offset=b.col_offset)
            next_iter_gen = _cfa([next_assign] + b.body, state, gen_true)
            next_iter_gen += state.get_continues()
            for c in next_iter_gen:
                c(init_id)

            loop_done_gen = list(state.get_breaks())

            state.pop_loop()

            if b.orelse:
                # if b.orelse and loop_ending_blocks:
                loop_done_gen += _cfa(b.orelse, state, gen_false)
            else:
                loop_done_gen += gen_false

            on_gen = loop_done_gen
            if not on_gen and PRUNE_UNREACHABLE_BLOCKS:
                return []
        elif isinstance(b, (_ast.Return, _ast.Raise)):
            cur_block.append(b)
            block_id = push_block(cur_block)
            state.returns.append(make_connect(block_id))
            return []
        elif isinstance(b, _ast.With):
            # XXX totally ignores the functionality of with statements

            # Have to save the context manager because the expression might not be valid later
            mgr_name = "__mgr_%s_%s_" % (b.lineno, b.col_offset)
            save_mgr = _ast.Assign([
                _ast.Name(mgr_name,
                          _ast.Store(),
                          lineno=b.lineno,
                          col_offset=b.col_offset,
                          not_real=True)
            ],
                                   b.context_expr,
                                   lineno=b.lineno,
                                   col_offset=b.col_offset,
                                   not_real=True)

            enter_func = _ast.Attribute(_ast.Name(mgr_name,
                                                  _ast.Load(),
                                                  lineno=b.lineno,
                                                  col_offset=b.col_offset,
                                                  not_real=True),
                                        "__enter__",
                                        _ast.Load(),
                                        lineno=b.lineno,
                                        col_offset=b.col_offset,
                                        not_real=True)
            bind = _ast.Call(enter_func, [], [],
                             None,
                             None,
                             lineno=b.lineno,
                             col_offset="__enter__()",
                             not_real=True)

            if b.optional_vars:
                assert isinstance(b.optional_vars, _ast.AST)
                init = _ast.Assign([b.optional_vars],
                                   bind,
                                   lineno=b.lineno,
                                   col_offset=b.col_offset,
                                   not_real=True)
            else:
                init = _ast.Expr(bind,
                                 lineno=b.lineno,
                                 col_offset=b.col_offset,
                                 not_real=True)

            exit_func = _ast.Attribute(_ast.Name(mgr_name,
                                                 _ast.Load(),
                                                 lineno=b.lineno,
                                                 col_offset=b.col_offset,
                                                 not_real=True),
                                       "__exit__",
                                       _ast.Load(),
                                       lineno=b.lineno,
                                       col_offset=b.col_offset,
                                       not_real=True)
            if SIMPLE_WITH_EXIT:
                exit_call = _ast.Call(exit_func, [], [],
                                      None,
                                      None,
                                      lineno=b.lineno,
                                      col_offset=b.col_offset,
                                      not_real=True)
            else:
                none_ = _ast.Name("None",
                                  _ast.Load(),
                                  lineno=b.lineno,
                                  col_offset=b.col_offset,
                                  not_real=True)
                exit_call = _ast.Call(exit_func, [none_, none_, none_], [],
                                      None,
                                      None,
                                      lineno=b.lineno,
                                      col_offset=b.col_offset,
                                      not_real=True)
            exit = _ast.Expr(exit_call,
                             lineno=b.lineno,
                             col_offset="__exit__()",
                             not_real=True)

            cur_block.extend([save_mgr, init])
            j = Jump()
            cur_block.append(j)
            next_block = push_block(cur_block)
            on_gen = [j.set_dest, make_connect(next_block)]
            cur_block = []

            body = b.body + [exit]
            next_gen = _cfa(body, state, on_gen)
            on_gen = next_gen
        else:
            raise Exception(b)

    if cur_block:
        j = Jump()
        cur_block.append(j)
        next = push_block(cur_block)
        return [j.set_dest, make_connect(next)]
    return on_gen

    return on_gen