Update Partial Reduction Verifier for more precise finding of combinations

dmnverifierapi/src/main/java/de/unikoblenz/fgbks/core/dmn/verification/verifier/impl/PartialReductionVerifier.java

@@ -57,16 +57,14 @@ public class PartialReductionVerifier extends AbstractVerifier {
       boolean hasCombination,
       VDmnRule subsumptionRule) {
     if (i == inColumns.size()) {
-      if (hasCombination) {
-        createCombinedRule(inColumns, clusterRules);
-        clusterRules.forEach(
-            rule -> vreFactory.addElement(VerificationResultEntryElement.create(rule)));
-        vreFactory.addVerificationFix(SHOW_RULES);
-        vreFactory.addToEntry(
-            VerificationClassification.INFO,
-            templateDecision(inColumns.get(0).getVDmnDecision()) + "Rules %s can be combined.",
-            getRulesRowsStrings(clusterRules));
-      }
+      createCombinedRule(inColumns, clusterRules);
+      clusterRules.forEach(
+          rule -> vreFactory.addElement(VerificationResultEntryElement.create(rule)));
+      vreFactory.addVerificationFix(SHOW_RULES);
+      vreFactory.addToEntry(
+          VerificationClassification.INFO,
+          templateDecision(inColumns.get(0).getVDmnDecision()) + "Rules %s can be combined.",
+          getRulesRowsStrings(clusterRules));
     } else {
       List<VDmnInputValue> rules =
           VDmnFunctions.getColumnValuesInRules(inColumns.get(i), clusterRules);
@@ -106,21 +104,7 @@ public class PartialReductionVerifier extends AbstractVerifier {
                 combinationCluster.add(true);
               }
             }
-            // 2. Find other combinations (only of no real combination
-            if (!found && !hasCombination) {
-              if (currentRuleValue
-                  .getBoundary()
-                  .createBi(COMBINE, currentRuleValueInner.getBoundary())
-                  .isPresent()) {
-                found = true;
-                List<VDmnRule> cluster = new ArrayList<>();
-                cluster.add(currentRuleValue.getVDmnRule());
-                cluster.add(currentRuleValueInner.getVDmnRule());
-                nClusters.add(cluster);
-                combinationCluster.add(true);
-              }
-            }
-            // 2. Find equal
+            // Find identical
             if (!found
                 && currentRuleValue
                 .getBoundary()
@@ -128,22 +112,32 @@ public class PartialReductionVerifier extends AbstractVerifier {
               List<VDmnRule> cluster = new ArrayList<>();
               cluster.add(currentRuleValue.getVDmnRule());
               cluster.add(currentRuleValueInner.getVDmnRule());
-              nClusters.add(cluster);
               combinationCluster.add(false);
-            }
+              nClusters.add(cluster);
+            } else // 2. Find other combinations (only of no real combination
+              if (!found
+                  && !hasCombination
+                  && currentRuleValue
+                  .getBoundary()
+                  .createBi(COMBINE, currentRuleValueInner.getBoundary())
+                  .isPresent()) {
+                List<VDmnRule> cluster = new ArrayList<>();
+                cluster.add(currentRuleValue.getVDmnRule());
+                cluster.add(currentRuleValueInner.getVDmnRule());
+                combinationCluster.add(true);
+                nClusters.add(cluster);
+              }
           }
         }
       }
       // nex col
       for (int x = 0; x < combinationCluster.size(); x++) {
-        if (nClusters.get(x).size() > 1) {
-          findPartialReduction(
-              inColumns,
-              i + 1,
-              nClusters.get(x),
-              combinationCluster.get(x) || hasCombination,
-              subsumptionRule);
-        }
+        findPartialReduction(
+            inColumns,
+            i + 1,
+            nClusters.get(x),
+            combinationCluster.get(x) || hasCombination,
+            subsumptionRule);
       }
     }
   }