ppapi/generators/idl_propertynode.py

   1 #!/usr/bin/env python
   2 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
   3 # Use of this source code is governed by a BSD-style license that can be
   4 # found in the LICENSE file.
   5
   6 """ Hierarchical property system for IDL AST """
   7 import re
   8 import sys
   9
  10 from idl_log import ErrOut, InfoOut, WarnOut
  11
  12 #
  13 # IDLPropertyNode
  14 #
  15 # A property node is a hierarchically aware system for mapping
  16 # keys to values, such that a local dictionary is search first,
  17 # followed by parent dictionaries in order.
  18 #
  19 class IDLPropertyNode(object):
  20   def __init__(self):
  21     self.parents = []
  22     self.property_map = {}
  23
  24   def AddParent(self, parent):
  25     assert parent
  26     self.parents.append(parent)
  27
  28   def SetProperty(self, name, val):
  29     self.property_map[name] = val
  30
  31   def GetProperty(self, name):
  32     # Check locally for the property, and return it if found.
  33     prop = self.property_map.get(name, None)
  34     if prop is not None:
  35       return prop
  36     # If not, seach parents in order
  37     for parent in self.parents:
  38       prop = parent.GetProperty(name)
  39       if prop is not None:
  40         return prop
  41     # Otherwise, it can not be found.
  42     return None
  43
  44   def GetPropertyLocal(self, name):
  45     # Search for the property, but only locally.
  46     return self.property_map.get(name, None)
  47
  48   def GetPropertyList(self):
  49     return self.property_map.keys()
  50
  51 #
  52 # Testing functions
  53 #
  54
  55 # Build a property node, setting the properties including a name, and
  56 # associate the children with this new node.
  57 #
  58 def BuildNode(name, props, children=None, parents=None):
  59   node = IDLPropertyNode()
  60   node.SetProperty('NAME', name)
  61   for prop in props:
  62     toks = prop.split('=')
  63     node.SetProperty(toks[0], toks[1])
  64   if children:
  65     for child in children:
  66       child.AddParent(node)
  67   if parents:
  68     for parent in parents:
  69       node.AddParent(parent)
  70   return node
  71
  72 def ExpectProp(node, name, val):
  73   found = node.GetProperty(name)
  74   if found != val:
  75     ErrOut.Log('Got property %s expecting %s' % (found, val))
  76     return 1
  77   return 0
  78
  79 #
  80 # Verify property inheritance
  81 #
  82 def PropertyTest():
  83   errors = 0
  84   left = BuildNode('Left', ['Left=Left'])
  85   right = BuildNode('Right', ['Right=Right'])
  86   top = BuildNode('Top', ['Left=Top', 'Right=Top'], [left, right])
  87
  88   errors += ExpectProp(top, 'Left', 'Top')
  89   errors += ExpectProp(top, 'Right', 'Top')
  90
  91   errors += ExpectProp(left, 'Left', 'Left')
  92   errors += ExpectProp(left, 'Right', 'Top')
  93
  94   errors += ExpectProp(right, 'Left', 'Top')
  95   errors += ExpectProp(right, 'Right', 'Right')
  96
  97   if not errors:
  98     InfoOut.Log('Passed PropertyTest')
  99   return errors
 100
 101
 102 def Main():
 103   errors = 0
 104   errors += PropertyTest()
 105
 106   if errors:
 107     ErrOut.Log('IDLNode failed with %d errors.' % errors)
 108     return  -1
 109   return 0
 110
 111
 112 if __name__ == '__main__':
 113   sys.exit(Main())
 114