Robot Framework 代码19之abstractdomwrapper.py

from types import StringTypes


class AbstractDomWrapper:
    
    """Base class for pydomwrapper.DomWrapper and jydomwrapper.DomWrapper"""
   
    def __init__(self, path):
        """Public attributes. These must be set by extending classes."""
        self.source = path
        self.name = ''
        self.attrs = {}
        self.text = ''
        self.children = []
   
    def _get_root(self, path, string):
        node = self._get_dom(path, string).firstChild
         # Ignore comments, doctypes, etc. before root node
        while node.nodeType != node.ELEMENT_NODE:
            node = node.nextSibling
        return node

    def get_nodes(self, path):
        """Returns a list of descendants matching given 'path'.
       
        Path must be a string in format 'child_name/grandchild_name/etc'. No
        slash is allowed at the beginning or end of the path string. Returns an
        empty list if no matching descendants found and raises AttributeError
        if path is invalid.
        """
        if type(path) not in StringTypes or path == '' or path[0] == '/' or path[-1] == '/':
            raise AttributeError("Invalid path '%s'" % str(path))
        matches = []
        for child in self.children:
            matches += child._get_matching_elements(path.split('/'))
        return matches
   
    def get_node(self, path):
        """Similar as get_nodes but checks that exactly one node is found.
       
        Node is returned as is (i.e. not in a list) and AttributeError risen if
        no match or more than one match found.
        """
        nodes = self.get_nodes(path)
        if len(nodes) == 0:
            raise AttributeError("No nodes matching path '%s' found" % path)
        if len(nodes) > 1:
            raise AttributeError("Multiple nodes matching path '%s' found" % path)
        return nodes[0]
   
    def get_attr(self, name, default=None):
        """Helper for getting node's attributes.
       
        Otherwise equivalent to 'node.attrs.get(name, default)' but raises
        an AttributeError if no value found and no default given.
        """
        ret = self.attrs.get(name, default)
        if ret is None:
            raise AttributeError("No attribute '%s' found" % name)
        return ret

    def __getattr__(self, name):
        """Syntactic sugar for get_nodes (e.g. dom.elem[0].subelem).
       
        Differs from get_nodes so that if not matching nodes are found an
        AttributeError is risen instead of returning an empty list."""
        nodes = self.get_nodes(name)
        if len(nodes) == 0:
            raise AttributeError("No nodes matching path '%s' found" % name)
        return nodes
   
    def __getitem__(self, name):
        """Syntactic sugar for get_node (e.g. dom['elem/subelem'])"""
        try:
            return self.get_node(name)
        except AttributeError:
            raise IndexError("No node '%s' found" % name)

    def __repr__(self):
        """Return node name. Mainly for debugging purposes."""
        return self.name

    def _get_matching_elements(self, tokens):
        if self.name != tokens[0]:
            return []
        elif len(tokens) == 1:
            return [ self ]
        else:
            matches = []
            for child in self.children:
                matches += child._get_matching_elements(tokens[1:])
            return matches
 

文件路径：C:\Python26\lib\site-packages\robot\abstractdomwrapper.py
功能：DomWrapper的基类，XML DOM 定义了访问和处理 XML 文档的标准方法。这里仅仅是读，暂不深入