old_contents: # -*- python -*-
  
  # stdlib imports
  import os
  import os.path as osp
  import sys
  
  # waf imports ---
  import waflib.Options
  import waflib.Utils
  import waflib.Logs as msg
  from waflib.Configure import conf
  
  _heptooldir = osp.dirname(osp.abspath(__file__))
  # add this directory to sys.path to ease the loading of other hepwaf tools
  if not _heptooldir in sys.path: sys.path.append(_heptooldir)
  
  ### ---------------------------------------------------------------------------
  @conf
  def _cmt_get_srcs_lst(self, source, root=None):
      '''hack to support implicit src/*cxx in CMT req-files'''
      if root is None:
          root = self.path
      if isinstance(source, (list, tuple)):
          src = []
          for s in source:
              src.extend(self._cmt_get_srcs_lst(s, root=root))
          return src
      elif not isinstance(source, type('')):
          ## a waflib.Node ?
          return [source]
      else:
          src_node = root.find_dir('src')
          srcs = root.ant_glob(source)
          if srcs:
              # OK. finders, keepers.
              pass
          elif src_node:
              # hack to mimick CMT's default (to take sources from src)
              srcs = src_node.ant_glob(source)
              pass
          if not srcs:
              # ok, try again from bldnode
              src_node = root.find_dir('src')
              srcs = root.get_bld().ant_glob(source)
              if srcs:
                  # OK. finders, keepers.
                  pass
              elif src_node:
                  # hack to mimick CMT's default (to take sources from src)
                  srcs = src_node.get_bld().ant_glob(source)
                  pass
              if not srcs:
                  # ok, maybe the output of a not-yet executed task
                  srcs = source
                  pass
              pass
          return waflib.Utils.to_list(srcs)
      self.fatal("unreachable")
      return []
  
new_contents: # -*- python -*-
  
  # stdlib imports
  import os
  import os.path as osp
  import sys
  
  # waf imports ---
  import waflib.Options
  import waflib.Utils
  import waflib.Logs as msg
  from waflib.Configure import conf
  
  _heptooldir = osp.dirname(osp.abspath(__file__))
  # add this directory to sys.path to ease the loading of other hepwaf tools
  if not _heptooldir in sys.path: sys.path.append(_heptooldir)
  
  ### ---------------------------------------------------------------------------
  @conf
  def _cmt_get_srcs_lst(self, source, root=None):
      '''hack to support implicit src/*cxx in CMT req-files'''
      if root is None:
          root = self.path
      if isinstance(source, (list, tuple)):
          src = []
          for s in source:
              src.extend(self._cmt_get_srcs_lst(s, root=root))
          return src
      elif not isinstance(source, type('')):
          ## a waflib.Node ?
          return [source]
      else:
          src_node = root.find_dir('src')
          srcs = root.ant_glob(source)
          if srcs:
              # OK. finders, keepers.
              pass
          elif src_node:
              # hack to mimick CMT's default (to take sources from src)
              srcs = src_node.ant_glob(source)
              pass
          if not srcs:
              # ok, try again from bldnode
              src_node = root.find_dir('src')
              srcs = root.get_bld().ant_glob(source)
              if srcs:
                  # OK. finders, keepers.
                  pass
              elif src_node:
                  # hack to mimick CMT's default (to take sources from src)
                  try:            srcs = src_node.get_bld().ant_glob(source)
                  except OSError: srcs = root.ant_glob(source)
                  pass
              if not srcs:
                  # ok, maybe the output of a not-yet executed task
                  srcs = source
                  pass
              pass
          return waflib.Utils.to_list(srcs)
      self.fatal("unreachable")
      return []
  
subject: handle case where 'src' does not exist