Exemplo n.º 1
0
 def _eval_element_not_cached(self, context, element):
     debug.dbg('eval_element %s@%s', element, element.start_pos)
     types = set()
     typ = element.type
     if typ in ('name', 'number', 'string', 'atom'):
         types = self.eval_atom(context, element)
     elif typ == 'keyword':
         # For False/True/None
         if element.value in ('False', 'True', 'None'):
             types.add(compiled.builtin_from_name(self, element.value))
         # else: print e.g. could be evaluated like this in Python 2.7
     elif typ == 'lambdef':
         types = set([er.FunctionContext(self, context, element)])
     elif typ == 'expr_stmt':
         types = self.eval_statement(context, element)
     elif typ in ('power', 'atom_expr'):
         first_child = element.children[0]
         if not (first_child.type == 'keyword' and first_child.value == 'await'):
             types = self.eval_atom(context, first_child)
             for trailer in element.children[1:]:
                 if trailer == '**':  # has a power operation.
                     right = self.eval_element(context, element.children[2])
                     types = set(precedence.calculate(self, context, types, trailer, right))
                     break
                 types = self.eval_trailer(context, types, trailer)
     elif typ in ('testlist_star_expr', 'testlist',):
         # The implicit tuple in statements.
         types = set([iterable.SequenceLiteralContext(self, context, element)])
     elif typ in ('not_test', 'factor'):
         types = self.eval_element(context, element.children[-1])
         for operator in element.children[:-1]:
             types = set(precedence.factor_calculate(self, types, operator))
     elif typ == 'test':
         # `x if foo else y` case.
         types = (self.eval_element(context, element.children[0]) |
                  self.eval_element(context, element.children[-1]))
     elif typ == 'operator':
         # Must be an ellipsis, other operators are not evaluated.
         # In Python 2 ellipsis is coded as three single dot tokens, not
         # as one token 3 dot token.
         assert element.value in ('.', '...')
         types = set([compiled.create(self, Ellipsis)])
     elif typ == 'dotted_name':
         types = self.eval_atom(context, element.children[0])
         for next_name in element.children[2::2]:
             # TODO add search_global=True?
             types = unite(
                 typ.py__getattribute__(next_name, name_context=context)
                 for typ in types
             )
         types = types
     elif typ == 'eval_input':
         types = self._eval_element_not_cached(context, element.children[0])
     elif typ == 'annassign':
         types = pep0484._evaluate_for_annotation(context, element.children[1])
     else:
         types = precedence.calculate_children(self, context, element.children)
     debug.dbg('eval_element result %s', types)
     return types
Exemplo n.º 2
0
    def eval_atom(self, context, atom):
        """
        Basically to process ``atom`` nodes. The parser sometimes doesn't
        generate the node (because it has just one child). In that case an atom
        might be a name or a literal as well.
        """
        if atom.type == 'name':
            # This is the first global lookup.
            stmt = atom.get_definition()
            if stmt.type == 'comp_for':
                stmt = tree.search_ancestor(
                    stmt, ('expr_stmt', 'lambda', 'funcdef', 'classdef'))
            if stmt is None or stmt.type != 'expr_stmt':
                # We only need to adjust the start_pos for statements, because
                # there the name cannot be used.
                stmt = atom
            return context.py__getattribute__(name_or_str=atom,
                                              position=stmt.start_pos,
                                              search_global=True)
        elif isinstance(atom, tree.Literal):
            return set([compiled.create(self, atom.eval())])
        else:
            c = atom.children
            if c[0].type == 'string':
                # Will be one string.
                types = self.eval_atom(context, c[0])
                for string in c[1:]:
                    right = self.eval_atom(context, string)
                    types = precedence.calculate(self, context, types, '+',
                                                 right)
                return types
            # Parentheses without commas are not tuples.
            elif c[0] == '(' and not len(c) == 2 \
                    and not(c[1].type == 'testlist_comp' and
                            len(c[1].children) > 1):
                return self.eval_element(context, c[1])

            try:
                comp_for = c[1].children[1]
            except (IndexError, AttributeError):
                pass
            else:
                if comp_for == ':':
                    # Dict comprehensions have a colon at the 3rd index.
                    try:
                        comp_for = c[1].children[3]
                    except IndexError:
                        pass

                if comp_for.type == 'comp_for':
                    return set([
                        iterable.Comprehension.from_atom(self, context, atom)
                    ])

            # It's a dict/list/tuple literal.
            array_node = c[1]
            try:
                array_node_c = array_node.children
            except AttributeError:
                array_node_c = []
            if c[0] == '{' and (array_node == '}' or ':' in array_node_c):
                context = iterable.DictLiteralContext(self, context, atom)
            else:
                context = iterable.SequenceLiteralContext(self, context, atom)
            return set([context])