tools/telemetry/catapult_base/refactor/annotated_symbol/reference.py

   1 # Copyright 2015 The Chromium Authors. All rights reserved.
   2 # Use of this source code is governed by a BSD-style license that can be
   3 # found in the LICENSE file.
   4
   5 import itertools
   6 import symbol
   7 import token
   8
   9 from catapult_base.refactor.annotated_symbol import base_symbol
  10 from catapult_base.refactor import snippet
  11
  12
  13 __all__ = [
  14     'Reference',
  15 ]
  16
  17
  18 class Reference(base_symbol.AnnotatedSymbol):
  19   @classmethod
  20   def Annotate(cls, nodes):
  21     if not nodes:
  22       return None
  23     if nodes[0].type != symbol.atom:
  24       return None
  25     if not nodes[0].children or nodes[0].children[0].type != token.NAME:
  26       return None
  27
  28     for i in xrange(1, len(nodes)):
  29       if not nodes:
  30         break
  31       if nodes[i].type != symbol.trailer:
  32         break
  33       if len(nodes[i].children) != 2:
  34         break
  35       if (nodes[i].children[0].type != token.DOT or
  36           nodes[i].children[1].type != token.NAME):
  37         break
  38     else:
  39       i = len(nodes)
  40
  41     return [cls(nodes[:i])] + nodes[i:]
  42
  43   def __init__(self, children):
  44     super(Reference, self).__init__(-1, children)
  45
  46   @property
  47   def type_name(self):
  48     return 'attribute_reference'
  49
  50   @property
  51   def value(self):
  52     return ''.join(token_snippet.value
  53                    for child in self.children
  54                    for token_snippet in child.children)
  55
  56   @value.setter
  57   def value(self, value):
  58     value_parts = value.split('.')
  59
  60     # If we have too many children, cut the list down to size.
  61     self._children = self._children[:len(value_parts)]
  62
  63     # Update child nodes.
  64     for child, value_part in itertools.izip_longest(
  65         self._children, value_parts):
  66       if child:
  67         # Modify existing children. This helps preserve comments and spaces.
  68         child.children[-1].value = value_part
  69       else:
  70         # Add children as needed.
  71         token_snippets = [
  72             snippet.TokenSnippet.Create(token.DOT, '.'),
  73             snippet.TokenSnippet.Create(token.NAME, value_part),
  74         ]
  75         self._children.append(snippet.Symbol(symbol.trailer, token_snippets))