remove exception for algorithm

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@27209 20353a03-c40f-0410-a6d1-a30d3c3de9de

product/ERP5/Document/BusinessPath.py

@@ -33,7 +33,6 @@ from AccessControl import ClassSecurityInfo
 from Products.CMFCore.PortalFolder import ContentFilter
 from Products.ERP5Type import Permissions, PropertySheet, Constraint, Interface
 from Products.ERP5.Document.Path import Path
-from Products.ERP5.Document.BusinessProcess import BackTrack
 
 import zope.interface
 
@@ -265,8 +264,9 @@ class BusinessPath(Path):
     if self.getParentValue().isStartDateReferential():
       return explanation.getStartDate()
     else:
-      return self.getExpectedStopDate(explanation, *args, **kwargs)\
-             - self.getLeadTime()
+      expected_date = self.getExpectedStopDate(explanation, *args, **kwargs)
+      if expected_date is not None:
+        return expected_date - self.getLeadTime()
 
   def _getPredecessorExpectedStartDate(self, explanation, predecessor_date=None, *args, **kwargs):
     if predecessor_date is None:
@@ -279,8 +279,9 @@ class BusinessPath(Path):
   def _getSuccessorExpectedStartDate(self, explanation, *args, **kwargs):
     node = self.getSuccessorValue()
     if node is not None:
-      return node.getExpectedBeginningDate(explanation, *args, **kwargs)\
-             - self.getLeadTime()
+      expected_date =  node.getExpectedBeginningDate(explanation, *args, **kwargs)
+      if expected_date is not None:
+        return expected_date - self.getLeadTime()
 
   def getExpectedStopDate(self, explanation, predecessor_date=None, *args, **kwargs):
     """
@@ -301,14 +302,16 @@ class BusinessPath(Path):
     if self.getParentValue().isStopDateReferential():
       return explanation.getStopDate()
     else:
-      return self.getExpectedStartDate(explanation, *args, **kwargs)\
-             + self.getLeadTime()
+      expected_date = self.getExpectedStartDate(explanation, *args, **kwargs)
+      if expected_date is not None:
+        return expected_date + self.getLeadTime()
 
   def _getPredecessorExpectedStopDate(self, explanation, *args, **kwargs):
     node = self.getPredecessorValue()
     if node is not None:
-      return node.getExpectedCompletionDate(explanation, *args, **kwargs)\
-             + self.getWaitTime() + self.getLeadTime()
+      expected_date = node.getExpectedCompletionDate(explanation, *args, **kwargs)
+      if expected_date is not None:
+        return expected_date + self.getWaitTime() + self.getLeadTime()
 
   def _getSuccessorExpectedStopDate(self, explanation, *args, **kwargs):
     node = self.getSuccessorValue()
@@ -338,19 +341,11 @@ class BusinessPath(Path):
       return root_explanation_method(
         explanation, visited=visited, *args, **kwargs)
 
-    predecessor_expected_date = None
-    try:
     predecessor_expected_date = predecessor_method(
       explanation, visited=visited, *args, **kwargs)
-    except BackTrack:
-      pass
 
-    successor_expected_date = None
-    try:
     successor_expected_date = successor_method(
       explanation, visited=visited, *args, **kwargs)
-    except BackTrack:
-      pass
 
     if successor_expected_date is not None or \
        predecessor_expected_date is not None:

product/ERP5/Document/BusinessProcess.py

@@ -34,12 +34,6 @@ from Products.ERP5Type import Permissions, PropertySheet, Constraint, Interface
 from Products.ERP5Type.XMLObject import XMLObject
 from Products.ERP5.Document.Path import Path
 
-class BackTrack(Exception):
-  # XXX this defined here until refactor 
-  """
-   This is a utility Exception for tree back tracking.
-  """
-
 class BusinessProcess(Path, XMLObject):
   """
     The BusinessProcess class is a container class which is used

product/ERP5/Document/BusinessState.py

@@ -32,7 +32,6 @@ from AccessControl import ClassSecurityInfo
 
 from Products.ERP5Type import Permissions, PropertySheet, Constraint, Interface
 from Products.ERP5Type.XMLObject import XMLObject
-from Products.ERP5.Document.BusinessProcess import BackTrack
 
 class BusinessState(XMLObject):
   """
@@ -89,11 +88,13 @@ class BusinessState(XMLObject):
     # Should be re-calculated?
     if 'predecessor_date' in kwargs:
       del kwargs['predecessor_date']
-    return min(self._getExpectedDateList(explanation,
+    date_list = self._getExpectedDateList(explanation,
                                           self.getSuccessorRelatedValueList(),
                                           self._getExpectedCompletionDate,
                                           *args,
-                                         **kwargs))
+                                          **kwargs)
+    if len(date_list) > 0:
+      return min(date_list)
 
   def _getExpectedCompletionDate(self, path, *args, **kwargs):
     return path.getExpectedStopDate(*args, **kwargs)
@@ -108,11 +109,13 @@ class BusinessState(XMLObject):
     # Should be re-calculated?
     if 'predecessor_date' in kwargs:
       del kwargs['predecessor_date']
-    return min(self._getExpectedDateList(explanation,
+    date_list = self._getExpectedDateList(explanation,
                                           self.getPredecessorRelatedValueList(),
                                           self._getExpectedBeginningDate,
                                           *args,
-                                         **kwargs))
+                                          **kwargs)
+    if len(date_list) > 0:
+      return min(date_list)
 
   def _getExpectedBeginningDate(self, path, *args, **kwargs):
     expected_date = path.getExpectedStartDate(*args, **kwargs)
@@ -141,10 +144,6 @@ class BusinessState(XMLObject):
         if expected_date is not None:
           expected_date_list.append(expected_date)
 
-    # if visiting leaf of tree
-    if len(expected_date_list) == 0:
-      raise BackTrack
-    else:
     return expected_date_list
 
   def getExpectedCompletionDuration(self, explanation):