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""" Implementation of the RECAP algorithm from Lewell et al. JCICS *38* 511-522 (1998)

The published algorithm is implemented more or less without
modification. The results are returned as a hierarchy of nodes instead
of just as a set of fragments. The hope is that this will allow a bit
more flexibility in working with the results.

For example:
>>> m = Chem.MolFromSmiles('C1CC1Oc1ccccc1-c1ncc(OC)cc1')
>>> res = Recap.RecapDecompose(m)
>>> res
<Chem.Recap.RecapHierarchyNode object at 0x00CDB5D0>
>>> res.children.keys()
['[*]C1CC1', '[*]c1ccccc1-c1ncc(OC)cc1', '[*]c1ccc(OC)cn1', '[*]c1ccccc1OC1CC1']
>>> res.GetAllChildren().keys()
['[*]c1ccccc1[*]', '[*]C1CC1', '[*]c1ccccc1-c1ncc(OC)cc1', '[*]c1ccc(OC)cn1', '[*]c1ccccc1OC1CC1']


To get the standard set of RECAP results, use GetLeaves():
>>> leaves=res.GetLeaves()
>>> leaves.keys()
['[*]c1ccccc1[*]', '[*]c1ccc(OC)cn1', '[*]C1CC1']
>>> leaf = leaves['[*]C1CC1']
>>> leaf.mol
<Chem.rdchem.Mol object at 0x00CBE0F0>


"""
import sys
import weakref
from rdkit import Chem
from rdkit.Chem import rdChemReactions as Reactions
from rdkit.six import iterkeys, iteritems, next

# These are the definitions that will be applied to fragment molecules:
reactionDefs = (
  "[#7;+0;D2,D3:1]!@C(!@=O)!@[#7;+0;D2,D3:2]>>[*][#7:1].[#7:2][*]", # urea

  "[C;!$(C([#7])[#7]):1](=!@[O:2])!@[#7;+0;!D1:3]>>[*][C:1]=[O:2].[*][#7:3]", # amide

  "[C:1](=!@[O:2])!@[O;+0:3]>>[*][C:1]=[O:2].[O:3][*]", # ester

  "[N;!D1;+0;!$(N-C=[#7,#8,#15,#16])](-!@[*:1])-!@[*:2]>>[*][*:1].[*:2][*]", # amines
  #"[N;!D1](!@[*:1])!@[*:2]>>[*][*:1].[*:2][*]", # amines

  # again: what about aromatics?
  "[#7;R;D3;+0:1]-!@[*:2]>>[*][#7:1].[*:2][*]", # cyclic amines

  "[#6:1]-!@[O;+0]-!@[#6:2]>>[#6:1][*].[*][#6:2]", # ether

  "[C:1]=!@[C:2]>>[C:1][*].[*][C:2]", # olefin

  "[n;+0:1]-!@[C:2]>>[n:1][*].[C:2][*]", # aromatic nitrogen - aliphatic carbon

  "[O:3]=[C:4]-@[N;+0:1]-!@[C:2]>>[O:3]=[C:4]-[N:1][*].[C:2][*]", # lactam nitrogen - aliphatic carbon

  "[c:1]-!@[c:2]>>[c:1][*].[*][c:2]", # aromatic carbon - aromatic carbon

  "[n;+0:1]-!@[c:2]>>[n:1][*].[*][c:2]", # aromatic nitrogen - aromatic carbon *NOTE* this is not part of the standard recap set.

  "[#7;+0;D2,D3:1]-!@[S:2](=[O:3])=[O:4]>>[#7:1][*].[*][S:2](=[O:3])=[O:4]", # sulphonamide
  )

reactions = tuple([Reactions.ReactionFromSmarts(x) for x in reactionDefs])


class RecapHierarchyNode(object):
  """ This class is used to hold the Recap hiearchy
  """
  mol=None
  children=None
  parents=None
  smiles = None
  def __init__(self,mol):
    self.mol=mol
    self.children = {}
    self.parents = {}

  def GetAllChildren(self):
    " returns a dictionary, keyed by SMILES, of children "
    res = {}
    for smi,child in iteritems(self.children):
      res[smi] = child
      child._gacRecurse(res,terminalOnly=False)
    return res

  def GetLeaves(self):
    " returns a dictionary, keyed by SMILES, of leaf (terminal) nodes "
    res = {}
    for smi,child in iteritems(self.children):
      if not len(child.children):
        res[smi] = child
      else:
        child._gacRecurse(res,terminalOnly=True)
    return res

  def getUltimateParents(self):
    """ returns all the nodes in the hierarchy tree that contain this
        node as a child
    """
    if not self.parents:
      res = [self]
    else:
      res = []
      for p in self.parents.values():
        for uP in p.getUltimateParents():
          if uP not in res:
            res.append(uP)
    return res
  
  def _gacRecurse(self,res,terminalOnly=False):
    for smi,child in iteritems(self.children):
      if not terminalOnly or not len(child.children):
        res[smi] = child
      child._gacRecurse(res,terminalOnly=terminalOnly)

  def __del__(self):
    self.children={}
    self.parent={}
    self.mol=None


def RecapDecompose(mol,allNodes=None,minFragmentSize=0,onlyUseReactions=None):
  """ returns the recap decomposition for a molecule """
  mSmi = Chem.MolToSmiles(mol,1)

  if allNodes is None:
    allNodes={}
  if mSmi in allNodes:
    return allNodes[mSmi]

  res = RecapHierarchyNode(mol)
  res.smiles =mSmi
  activePool={mSmi:res}
  allNodes[mSmi]=res
  while activePool:
    nSmi = next(iterkeys(activePool))
    node = activePool.pop(nSmi)
    if not node.mol: continue
    for rxnIdx,reaction in enumerate(reactions):
      if onlyUseReactions and rxnIdx not in onlyUseReactions:
        continue
      #print '  .',nSmi
      #print '         !!!!',rxnIdx,nSmi,reactionDefs[rxnIdx]
      ps = reaction.RunReactants((node.mol,))
      #print '    ',len(ps)
      if ps:
        for prodSeq in ps:
          seqOk=True
          # we want to disqualify small fragments, so sort the product sequence by size
          # and then look for "forbidden" fragments
          tSeq = [(prod.GetNumAtoms(onlyExplicit=True),idx) for idx,prod in enumerate(prodSeq)]
          tSeq.sort()
          ts=[(x,prodSeq[y]) for x,y in tSeq]
          prodSeq=ts
          for nats,prod in prodSeq:
            try:
              Chem.SanitizeMol(prod)
            except:
              continue
            pSmi = Chem.MolToSmiles(prod,1)
            if minFragmentSize>0:
              nDummies = pSmi.count('*')
              if nats-nDummies<minFragmentSize:
                seqOk=False
                break
            # don't forget after replacing dummy atoms to remove any empty
            # branches:
            elif pSmi.replace('[*]','').replace('()','') in ('','C','CC','CCC'):
              seqOk=False
              break
            prod.pSmi = pSmi
          if seqOk:
            for nats,prod in prodSeq:
              pSmi = prod.pSmi
              #print '\t',nats,pSmi
              if not pSmi in allNodes:
                pNode = RecapHierarchyNode(prod)
                pNode.smiles=pSmi
                pNode.parents[nSmi]=weakref.proxy(node)
                node.children[pSmi]=pNode
                activePool[pSmi] = pNode
                allNodes[pSmi]=pNode
              else:
                pNode=allNodes[pSmi]
                pNode.parents[nSmi]=weakref.proxy(node)
                node.children[pSmi]=pNode
            #print '                >>an:',allNodes.keys()
  return res

      
# ------- ------- ------- ------- ------- ------- ------- -------
# Begin testing code
if __name__=='__main__':
  import unittest
  class TestCase(unittest.TestCase):
    def test1(self):
      m = Chem.MolFromSmiles('C1CC1Oc1ccccc1-c1ncc(OC)cc1')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.children.keys())==4)
      self.assertTrue(len(res.GetAllChildren().keys())==5)
      self.assertTrue(len(res.GetLeaves().keys())==3)
    def test2(self):
      m = Chem.MolFromSmiles('CCCOCCC')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(res.children=={})
    def test3(self):
      allNodes={}
      m = Chem.MolFromSmiles('c1ccccc1-c1ncccc1')
      res = RecapDecompose(m,allNodes=allNodes)
      self.assertTrue(res)
      self.assertTrue(len(res.children.keys())==2)
      self.assertTrue(len(allNodes.keys())==3)

      m = Chem.MolFromSmiles('COc1ccccc1-c1ncccc1')
      res = RecapDecompose(m,allNodes=allNodes)
      self.assertTrue(res)
      self.assertTrue(len(res.children.keys())==2)
      # we get two more nodes from that:
      self.assertTrue(len(allNodes.keys())==5)
      self.assertTrue('[*]c1ccccc1OC' in allNodes)
      self.assertTrue('[*]c1ccccc1' in allNodes)
      
      m = Chem.MolFromSmiles('C1CC1Oc1ccccc1-c1ncccc1')
      res = RecapDecompose(m,allNodes=allNodes)
      self.assertTrue(res)
      self.assertTrue(len(res.children.keys())==4)
      self.assertTrue(len(allNodes.keys())==10)
      
    def testSFNetIssue1801871(self):
      m = Chem.MolFromSmiles('c1ccccc1OC(Oc1ccccc1)Oc1ccccc1')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==2)
      ks = res.GetLeaves().keys()
      self.assertFalse('[*]C([*])[*]' in ks)
      self.assertTrue('[*]c1ccccc1' in ks)
      self.assertTrue('[*]C([*])Oc1ccccc1' in ks)
      
    def testSFNetIssue1804418(self):
      m = Chem.MolFromSmiles('C1CCCCN1CCCC')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==2)
      ks = res.GetLeaves().keys()
      self.assertTrue('[*]N1CCCCC1' in ks)
      self.assertTrue('[*]CCCC' in ks)

    def testMinFragmentSize(self):
      m = Chem.MolFromSmiles('CCCOCCC')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(res.children=={})
      res = RecapDecompose(m,minFragmentSize=3)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==1)
      ks = res.GetLeaves().keys()
      self.assertTrue('[*]CCC' in ks)

      m = Chem.MolFromSmiles('CCCOCC')
      res = RecapDecompose(m,minFragmentSize=3)
      self.assertTrue(res)
      self.assertTrue(res.children=={})

      m = Chem.MolFromSmiles('CCCOCCOC')
      res = RecapDecompose(m,minFragmentSize=2)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==2)
      ks = res.GetLeaves().keys()
      self.assertTrue('[*]CCC' in ks)
      ks = res.GetLeaves().keys()
      self.assertTrue('[*]CCOC' in ks)
      
    def testAmideRxn(self):
      m = Chem.MolFromSmiles('C1CC1C(=O)NC1OC1')
      res = RecapDecompose(m,onlyUseReactions=[1])
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==2)
      ks = res.GetLeaves().keys()
      self.assertTrue('[*]C(=O)C1CC1' in ks)
      self.assertTrue('[*]NC1CO1' in ks)

      m = Chem.MolFromSmiles('C1CC1C(=O)N(C)C1OC1')
      res = RecapDecompose(m,onlyUseReactions=[1])
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==2)
      ks = res.GetLeaves().keys()
      self.assertTrue('[*]C(=O)C1CC1' in ks)
      self.assertTrue('[*]N(C)C1CO1' in ks)

      m = Chem.MolFromSmiles('C1CC1C(=O)n1cccc1')
      res = RecapDecompose(m,onlyUseReactions=[1])
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==2)
      ks = res.GetLeaves().keys()
      self.assertTrue('[*]C(=O)C1CC1' in ks)
      self.assertTrue('[*]n1cccc1' in ks)

      m = Chem.MolFromSmiles('C1CC1C(=O)CC1OC1')
      res = RecapDecompose(m,onlyUseReactions=[1])
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==0)

      m = Chem.MolFromSmiles('C1CCC(=O)NC1')
      res = RecapDecompose(m,onlyUseReactions=[1])
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==0)

      m = Chem.MolFromSmiles('CC(=O)NC')
      res = RecapDecompose(m,onlyUseReactions=[1])
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==2)
      ks = res.GetLeaves().keys()

      m = Chem.MolFromSmiles('CC(=O)N')
      res = RecapDecompose(m,onlyUseReactions=[1])
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==0)

      m = Chem.MolFromSmiles('C(=O)NCCNC(=O)CC')
      res = RecapDecompose(m,onlyUseReactions=[1])
      self.assertTrue(res)
      self.assertTrue(len(res.children)==4)
      self.assertTrue(len(res.GetLeaves())==3)

    def testEsterRxn(self):
      m = Chem.MolFromSmiles('C1CC1C(=O)OC1OC1')
      res = RecapDecompose(m,onlyUseReactions=[2])
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==2)
      ks = res.GetLeaves().keys()
      self.assertTrue('[*]C(=O)C1CC1' in ks)
      self.assertTrue('[*]OC1CO1' in ks)
      
      m = Chem.MolFromSmiles('C1CC1C(=O)CC1OC1')
      res = RecapDecompose(m,onlyUseReactions=[2])
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==0)

      m = Chem.MolFromSmiles('C1CCC(=O)OC1')
      res = RecapDecompose(m,onlyUseReactions=[2])
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==0)

    def testUreaRxn(self):
      m = Chem.MolFromSmiles('C1CC1NC(=O)NC1OC1')
      res = RecapDecompose(m,onlyUseReactions=[0])
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==2)
      ks = res.GetLeaves().keys()
      self.assertTrue('[*]NC1CC1' in ks)
      self.assertTrue('[*]NC1CO1' in ks)
      
      m = Chem.MolFromSmiles('C1CC1NC(=O)N(C)C1OC1')
      res = RecapDecompose(m,onlyUseReactions=[0])
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==2)
      ks = res.GetLeaves().keys()
      self.assertTrue('[*]NC1CC1' in ks)
      self.assertTrue('[*]N(C)C1CO1' in ks)

      m = Chem.MolFromSmiles('C1CCNC(=O)NC1C')
      res = RecapDecompose(m,onlyUseReactions=[0])
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==0)

      m = Chem.MolFromSmiles('c1cccn1C(=O)NC1OC1')
      res = RecapDecompose(m,onlyUseReactions=[0])
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==2)
      ks = res.GetLeaves().keys()
      self.assertTrue('[*]n1cccc1' in ks)
      self.assertTrue('[*]NC1CO1' in ks)

      m = Chem.MolFromSmiles('c1cccn1C(=O)n1c(C)ccc1')
      res = RecapDecompose(m,onlyUseReactions=[0])
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==2)
      ks = res.GetLeaves().keys()
      self.assertTrue('[*]n1cccc1C' in ks)

    def testAmineRxn(self):
      m = Chem.MolFromSmiles('C1CC1N(C1NC1)C1OC1')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==3)
      ks = res.GetLeaves().keys()
      self.assertTrue('[*]C1CC1' in ks)
      self.assertTrue('[*]C1CO1' in ks)
      self.assertTrue('[*]C1CN1' in ks)
      
      m = Chem.MolFromSmiles('c1ccccc1N(C1NC1)C1OC1')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==3)
      ks = res.GetLeaves().keys()
      self.assertTrue('[*]c1ccccc1' in ks)
      self.assertTrue('[*]C1CO1' in ks)
      self.assertTrue('[*]C1CN1' in ks)
      
      m = Chem.MolFromSmiles('c1ccccc1N(c1ncccc1)C1OC1')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==3)
      ks = res.GetLeaves().keys()
      self.assertTrue('[*]c1ccccc1' in ks)
      self.assertTrue('[*]c1ccccn1' in ks)
      self.assertTrue('[*]C1CO1' in ks)
      
      m = Chem.MolFromSmiles('c1ccccc1N(c1ncccc1)c1ccco1')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==3)
      ks = res.GetLeaves().keys()
      self.assertTrue('[*]c1ccccc1' in ks)
      self.assertTrue('[*]c1ccccn1' in ks)
      self.assertTrue('[*]c1ccco1' in ks)

      m = Chem.MolFromSmiles('C1CCCCN1C1CC1')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==2)
      ks = res.GetLeaves().keys()
      self.assertTrue('[*]N1CCCCC1' in ks)
      self.assertTrue('[*]C1CC1' in ks)

      m = Chem.MolFromSmiles('C1CCC2N1CC2')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==0)

    def testEtherRxn(self):
      m = Chem.MolFromSmiles('C1CC1OC1OC1')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==2)
      ks = res.GetLeaves().keys()
      self.assertTrue('[*]C1CC1' in ks)
      self.assertTrue('[*]C1CO1' in ks)
      
      m = Chem.MolFromSmiles('C1CCCCO1')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==0)

      m = Chem.MolFromSmiles('c1ccccc1OC1OC1')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==2)
      ks = res.GetLeaves().keys()
      self.assertTrue('[*]c1ccccc1' in ks)
      self.assertTrue('[*]C1CO1' in ks)
      
      m = Chem.MolFromSmiles('c1ccccc1Oc1ncccc1')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==2)
      ks = res.GetLeaves().keys()
      self.assertTrue('[*]c1ccccc1' in ks)
      self.assertTrue('[*]c1ccccn1' in ks)
      
    def testOlefinRxn(self):
      m = Chem.MolFromSmiles('ClC=CBr')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==2)
      ks = res.GetLeaves().keys()
      self.assertTrue('[*]CCl' in ks)
      self.assertTrue('[*]CBr' in ks)
      
      m = Chem.MolFromSmiles('C1CC=CC1')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==0)

    def testAromNAliphCRxn(self):
      m = Chem.MolFromSmiles('c1cccn1CCCC')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==2)
      ks = res.GetLeaves().keys()
      self.assertTrue('[*]n1cccc1' in ks)
      self.assertTrue('[*]CCCC' in ks)
      
      m = Chem.MolFromSmiles('c1ccc2n1CCCC2')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==0)

    def testLactamNAliphCRxn(self):
      m = Chem.MolFromSmiles('C1CC(=O)N1CCCC')
      res = RecapDecompose(m,onlyUseReactions=[8])
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==2)
      ks = res.GetLeaves().keys()
      self.assertTrue('[*]N1CCC1=O' in ks)
      self.assertTrue('[*]CCCC' in ks)
      
      m = Chem.MolFromSmiles('O=C1CC2N1CCCC2')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==0)

    def testAromCAromCRxn(self):
      m = Chem.MolFromSmiles('c1ccccc1c1ncccc1')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==2)
      ks = res.GetLeaves().keys()
      self.assertTrue('[*]c1ccccc1' in ks)
      self.assertTrue('[*]c1ccccn1' in ks)
      
      m = Chem.MolFromSmiles('c1ccccc1C1CC1')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==0)

    def testAromNAromCRxn(self):
      m = Chem.MolFromSmiles('c1cccn1c1ccccc1')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==2)
      ks = res.GetLeaves().keys()
      self.assertTrue('[*]n1cccc1' in ks)
      self.assertTrue('[*]c1ccccc1' in ks)
      
    def testSulfonamideRxn(self):
      m = Chem.MolFromSmiles('CCCNS(=O)(=O)CC')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==2)
      ks = res.GetLeaves().keys()
      self.assertTrue('[*]NCCC' in ks)
      self.assertTrue('[*]S(=O)(=O)CC' in ks)
      
      m = Chem.MolFromSmiles('c1cccn1S(=O)(=O)CC')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==2)
      ks = res.GetLeaves().keys()
      self.assertTrue('[*]n1cccc1' in ks)
      self.assertTrue('[*]S(=O)(=O)CC' in ks)

      m = Chem.MolFromSmiles('C1CNS(=O)(=O)CC1')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==0)

    def testSFNetIssue1881803(self):
      m = Chem.MolFromSmiles('c1ccccc1n1cccc1')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==2)
      m = Chem.MolFromSmiles('c1ccccc1[n+]1ccccc1')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==0)

      m = Chem.MolFromSmiles('C1CC1NC(=O)CC')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==2)
      m = Chem.MolFromSmiles('C1CC1[NH+]C(=O)CC')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==0)

      m = Chem.MolFromSmiles('C1CC1NC(=O)NC1CCC1')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==2)
      m = Chem.MolFromSmiles('C1CC1[NH+]C(=O)[NH+]C1CCC1')
      res = RecapDecompose(m)
      self.assertTrue(res)
      self.assertTrue(len(res.GetLeaves())==0)
      
  unittest.main()