Source Code for Module SCons.Node.Python

  1  """scons.Node.Python 
  2   
  3  Python nodes. 
  4   
  5  """ 
  6   
  7  # 
  8  # Copyright (c) 2001 - 2019 The SCons Foundation 
  9  # 
 10  # Permission is hereby granted, free of charge, to any person obtaining 
 11  # a copy of this software and associated documentation files (the 
 12  # "Software"), to deal in the Software without restriction, including 
 13  # without limitation the rights to use, copy, modify, merge, publish, 
 14  # distribute, sublicense, and/or sell copies of the Software, and to 
 15  # permit persons to whom the Software is furnished to do so, subject to 
 16  # the following conditions: 
 17  # 
 18  # The above copyright notice and this permission notice shall be included 
 19  # in all copies or substantial portions of the Software. 
 20  # 
 21  # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY 
 22  # KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE 
 23  # WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 
 24  # NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE 
 25  # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 
 26  # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 
 27  # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 
 28  # 
 29   
 30  __revision__ = "src/engine/SCons/Node/Python.py 3a41ed6b288cee8d085373ad7fa02894e1903864 2019-01-23 17:30:35 bdeegan" 
 31   
 32  import SCons.Node 
 33   
 34 -class ValueNodeInfo(SCons.Node.NodeInfoBase): 
 35      __slots__ = ('csig',) 
 36      current_version_id = 2 
 37   
 38      field_list = ['csig'] 
 39   
 40 -    def str_to_node(self, s): 
 41          return Value(s) 
 42   
 43 -    def __getstate__(self): 
 44          """ 
 45          Return all fields that shall be pickled. Walk the slots in the class 
 46          hierarchy and add those to the state dictionary. If a '__dict__' slot is 
 47          available, copy all entries to the dictionary. Also include the version 
 48          id, which is fixed for all instances of a class. 
 49          """ 
 50          state = getattr(self, '__dict__', {}).copy() 
 51          for obj in type(self).mro(): 
 52              for name in getattr(obj,'__slots__',()): 
 53                  if hasattr(self, name): 
 54                      state[name] = getattr(self, name) 
 55   
 56          state['_version_id'] = self.current_version_id 
 57          try: 
 58              del state['__weakref__'] 
 59          except KeyError: 
 60              pass 
 61   
 62          return state 
 63   
 64 -    def __setstate__(self, state): 
 65          """ 
 66          Restore the attributes from a pickled state. 
 67          """ 
 68          # TODO check or discard version 
 69          del state['_version_id'] 
 70          for key, value in state.items(): 
 71              if key not in ('__weakref__',): 
 72                  setattr(self, key, value) 
 73   
 74   
 75 -class ValueBuildInfo(SCons.Node.BuildInfoBase): 
 76      __slots__ = () 
 77      current_version_id = 2 
 78   
 79 -class Value(SCons.Node.Node): 
 80      """A class for Python variables, typically passed on the command line 
 81      or generated by a script, but not from a file or some other source. 
 82      """ 
 83   
 84      NodeInfo = ValueNodeInfo 
 85      BuildInfo = ValueBuildInfo 
 86   
 87 -    def __init__(self, value, built_value=None): 
 88          SCons.Node.Node.__init__(self) 
 89          self.value = value 
 90          self.changed_since_last_build = 6 
 91          self.store_info = 0 
 92          if built_value is not None: 
 93              self.built_value = built_value 
 94   
 95 -    def str_for_display(self): 
 96          return repr(self.value) 
 97   
 98 -    def __str__(self): 
 99          return str(self.value) 
100   
101 -    def make_ready(self): 
102          self.get_csig() 
103   
104 -    def build(self, **kw): 
105          if not hasattr(self, 'built_value'): 
106              SCons.Node.Node.build(self, **kw) 
107   
108      is_up_to_date = SCons.Node.Node.children_are_up_to_date 
109   
110 -    def is_under(self, dir): 
111          # Make Value nodes get built regardless of 
112          # what directory scons was run from. Value nodes 
113          # are outside the filesystem: 
114          return 1 
115   
116 -    def write(self, built_value): 
117          """Set the value of the node.""" 
118          self.built_value = built_value 
119   
120 -    def read(self): 
121          """Return the value. If necessary, the value is built.""" 
122          self.build() 
123          if not hasattr(self, 'built_value'): 
124              self.built_value = self.value 
125          return self.built_value 
126   
127 -    def get_text_contents(self): 
128          """By the assumption that the node.built_value is a 
129          deterministic product of the sources, the contents of a Value 
130          are the concatenation of all the contents of its sources.  As 
131          the value need not be built when get_contents() is called, we 
132          cannot use the actual node.built_value.""" 
133          ###TODO: something reasonable about universal newlines 
134          contents = str(self.value) 
135          for kid in self.children(None): 
136              contents = contents + kid.get_contents().decode() 
137          return contents 
138   
139 -    def get_contents(self): 
140          """ 
141          Get contents for signature calculations. 
142          :return: bytes 
143          """ 
144          text_contents = self.get_text_contents() 
145          try: 
146              return text_contents.encode() 
147          except UnicodeDecodeError: 
148              # Already encoded as python2 str are bytes 
149              return text_contents 
150   
151   
152 -    def changed_since_last_build(self, target, prev_ni): 
153          cur_csig = self.get_csig() 
154          try: 
155              return cur_csig != prev_ni.csig 
156          except AttributeError: 
157              return 1 
158   
159 -    def get_csig(self, calc=None): 
160          """Because we're a Python value node and don't have a real 
161          timestamp, we get to ignore the calculator and just use the 
162          value contents. 
163   
164          Returns string. Ideally string of hex digits. (Not bytes) 
165          """ 
166          try: 
167              return self.ninfo.csig 
168          except AttributeError: 
169              pass 
170   
171          contents = self.get_text_contents() 
172   
173          self.get_ninfo().csig = contents 
174          return contents 
175   
176  # Local Variables: 
177  # tab-width:4 
178  # indent-tabs-mode:nil 
179  # End: 
180  # vim: set expandtab tabstop=4 shiftwidth=4: 
181