Move //mojo/{public, edk} underneath //third_party

mojo/public/third_party/jinja2/visitor.py

-# -*- coding: utf-8 -*-
-"""
-    jinja2.visitor
-    ~~~~~~~~~~~~~~
-
-    This module implements a visitor for the nodes.
-
-    :copyright: (c) 2010 by the Jinja Team.
-    :license: BSD.
-"""
-from jinja2.nodes import Node
-
-
-class NodeVisitor(object):
-    """Walks the abstract syntax tree and call visitor functions for every
-    node found.  The visitor functions may return values which will be
-    forwarded by the `visit` method.
-
-    Per default the visitor functions for the nodes are ``'visit_'`` +
-    class name of the node.  So a `TryFinally` node visit function would
-    be `visit_TryFinally`.  This behavior can be changed by overriding
-    the `get_visitor` function.  If no visitor function exists for a node
-    (return value `None`) the `generic_visit` visitor is used instead.
-    """
-
-    def get_visitor(self, node):
-        """Return the visitor function for this node or `None` if no visitor
-        exists for this node.  In that case the generic visit function is
-        used instead.
-        """
-        method = 'visit_' + node.__class__.__name__
-        return getattr(self, method, None)
-
-    def visit(self, node, *args, **kwargs):
-        """Visit a node."""
-        f = self.get_visitor(node)
-        if f is not None:
-            return f(node, *args, **kwargs)
-        return self.generic_visit(node, *args, **kwargs)
-
-    def generic_visit(self, node, *args, **kwargs):
-        """Called if no explicit visitor function exists for a node."""
-        for node in node.iter_child_nodes():
-            self.visit(node, *args, **kwargs)
-
-
-class NodeTransformer(NodeVisitor):
-    """Walks the abstract syntax tree and allows modifications of nodes.
-
-    The `NodeTransformer` will walk the AST and use the return value of the
-    visitor functions to replace or remove the old node.  If the return
-    value of the visitor function is `None` the node will be removed
-    from the previous location otherwise it's replaced with the return
-    value.  The return value may be the original node in which case no
-    replacement takes place.
-    """
-
-    def generic_visit(self, node, *args, **kwargs):
-        for field, old_value in node.iter_fields():
-            if isinstance(old_value, list):
-                new_values = []
-                for value in old_value:
-                    if isinstance(value, Node):
-                        value = self.visit(value, *args, **kwargs)
-                        if value is None:
-                            continue
-                        elif not isinstance(value, Node):
-                            new_values.extend(value)
-                            continue
-                    new_values.append(value)
-                old_value[:] = new_values
-            elif isinstance(old_value, Node):
-                new_node = self.visit(old_value, *args, **kwargs)
-                if new_node is None:
-                    delattr(node, field)
-                else:
-                    setattr(node, field, new_node)
-        return node
-
-    def visit_list(self, node, *args, **kwargs):
-        """As transformers may return lists in some places this method
-        can be used to enforce a list as return value.
-        """
-        rv = self.visit(node, *args, **kwargs)
-        if not isinstance(rv, list):
-            rv = [rv]
-        return rv