[Scons-users] Overriding Object to force global dependency

[Greg Ward]

Hi all --

I want to force every single *.o file in my build to artificially
depend on something. (We have a homebrew tool that downloads and
unpacks specific versions of all third-party dependencies -- GCC,
C/C++ libraries, Java libraries, etc. This tool must run first, and
everything else should depend on its output.)

The obvious thing to do is override env.Object(), but I'm not sure how
to do that. I tried it with env.AddMethod, and that only half worked.
Here's my override:

  _Object = env.Object
  def Object(env, *args, **kwargs):
      global _Object, dummy
      print('Object override: args=%s' % map(str, args))
      obj = _Object(*args, **kwargs)
      env.Depends(obj, dummy)
      return obj
  
  env.AddMethod(Object, 'Object')

('dummy' is the output of that homebrew dependency tool.)

This works as long as I only ever use one env object. But as soon as I
do

  env = env.Clone()

it stops working. The clone has the original Object() method, not
mine. ;-(

Is there a good way to do this?

Thanks --

        Greg