Change the determine_value_indexes function to actually do what it promises

src/Products/ZCatalog/CatalogReport.py

@@ -20,25 +20,26 @@ from Products.PluginIndexes.interfaces import IUniqueValueIndex
 writelock = allocate_lock()
 reports = {}
 
-MAX_DISTINCT_VALUES = 20
+MAX_DISTINCT_VALUES = 10
 
 LOG = logging.getLogger('CatalogReport')
 
 
 def determine_value_indexes(catalog):
     # This function determines all indexes whose values should be respected
-    # in the prioritymap key. A index type needs to be registered in the
-    # VALUETYPES module global and the number of unique values needs to be
+    # in the report key. The number of unique values for the index needs to be
     # lower than the MAX_DISTINCT_VALUES watermark.
     valueindexes = []
     for name, index in catalog.indexes.items():
         if IUniqueValueIndex.providedBy(index):
-            if len(index) < MAX_DISTINCT_VALUES:
-                # Checking for len of an index should be fast. It's a stored
-                # BTrees.Length value and requires no calculation.
+            values = index.uniqueValues()
+            if values and len(values) < MAX_DISTINCT_VALUES:
+                # Only consider indexes which actually return a number
+                # greater than zero
                 valueindexes.append(name)
     return frozenset(valueindexes)
 
+
 def make_key(catalog,request):
     valueindexes = determine_value_indexes(catalog)
     

src/Products/ZCatalog/tests/testCatalog.py

@@ -870,12 +870,11 @@ class TestCatalogReport(unittest.TestCase):
         self.zcat.addIndex('title', 'TextIndex')
         self.zcat._catalog.vocabulary = vocabulary
 
-        for i in range(10):
+        for i in range(9):
             obj = zdummy(i)
             obj.big = i > 5
             self.zcat.catalog_object(obj, str(i))
 
-
      def test_ReportLength(self):
          """ tests the report aggregation """
          
@@ -938,15 +937,12 @@ class TestCatalogReport(unittest.TestCase):
          key = ('sort_on', ('num', '[3, 4, 5]'))
          self.zcat.manage_resetCatalogReport()
 
-         self.zcat.searchResults(num=[5,4,3],sort_on='num')
-         self.zcat.searchResults(num=(3,4,5),sort_on='num')
+         self.zcat.searchResults(num=[5,4,3], sort_on='num')
+         self.zcat.searchResults(num=(3,4,5), sort_on='num')
          r = self.zcat.getCatalogReport()[0]
 
-         #print 'hits: %(counter)s, mean duration: %(duration)3.2fms, key: %(query)s' % r
-         
-         self.assertEqual(r['query'],key)
-         self.assertEqual(r['counter'],2)  
-         
+         self.assertEqual(r['query'], key)
+         self.assertEqual(r['counter'], 2)
 
 
 def test_suite():