Added comesBefore to VentooModule

1 files changed, 28 insertions, 2 deletions

diff --git a/src/ventoo/VentooModule.py b/src/ventoo/VentooModule.py
index 35c79f9..e320766 100644
--- a/src/ventoo/VentooModule.py
+++ b/src/ventoo/VentooModule.py
@@ -64,9 +64,35 @@ class VentooModule:
         try:
             elem = self.xmlTree.xpath(osp.join(xPath))
             if len(elem) >= 1 and not elem[0].get("docurl") == None:
-                #pdb.set_trace()
                 return "file:///"+osp.abspath(osp.join(self.docRoot, augeas_utils.stripBothSlashes(elem[0].get("docurl"))))
         except etree.XPathEvalError:
             pass
         return None
-    
+
+
+    """
+    Returns true if a comes before b
+    Raise ValueError if either a or b are not in the xml file.
+    a and b must both have the same parent node.
+    a and b are both tags, not paths.
+    """
+    def comesBefore(self, a, b):
+        try:
+            elemAlist = self.xmlTree.xpath("//"+a)
+            elemBlist = self.xmlTree.xpath("//"+b)
+        except etree.XPathEvalError:
+            raise ValueError("Could not find one of "+b)
+        if len(elemBlist) != 1:
+            return ValueError("Could not find one of "+b)
+        if len(elemAlist) != 1:
+            return ValueError("Could not find one of "+a)
+        elemAparent = elemAlist[0].getparent()
+        elemBparent = elemBlist[0].getparent()
+        if elemBparent.tag != elemAparent.tag:
+            raise ValueError(a+" and "+b+" do not have the same parent.")
+        for child in elemAparent:
+            if child.tag == elemBlist[0].tag:
+                return False
+            if child.tag == elemAlist[0].tag:
+                return True
+        raise RuntimeError("Something is wrong in comesBefore in VentooModule...")