fixed a failing test case

Author: StevenArzt

soot-infoflow/src/soot/jimple/infoflow/data/Abstraction.java

@@ -121,6 +121,11 @@ public boolean equals(Abstraction abs1, Abstraction abs2) {
 					return false;
 			} else if (!abs1.predecessor.equals(abs2.predecessor))
 				return false;
+			if (abs1.currentStmt == null) {
+				if (abs2.currentStmt != null)
+					return false;
+			} else if (!abs1.currentStmt.equals(abs2.currentStmt))
+				return false;
 
 			return abs1.localEquals(abs2);
 		}

soot-infoflow/src/soot/jimple/infoflow/data/SourceContextAndPath.java

@@ -127,6 +127,7 @@ public SourceContextAndPath extendPath(Abstraction abs, PathConfiguration pathCo
 			if (scap.path == null)
 				scap.path = new ExtensibleList<Abstraction>();
 			scap.path.add(abs);
+
 			if (pathConfig != null && pathConfig.getMaxPathLength() > 0
 					&& scap.path.size() > pathConfig.getMaxPathLength())
 				return null;

soot-infoflow/src/soot/jimple/infoflow/problems/BackwardsInfoflowProblem.java

@@ -119,8 +119,7 @@ private Set<Abstraction> computeAliases(final DefinitionStmt defStmt, Value left
 				assert !source.getAccessPath().isEmpty();
 
 				// A backward analysis looks for aliases of existing taints and
-				// thus
-				// cannot create new taints out of thin air
+				// thus cannot create new taints out of thin air
 				if (source == getZeroValue())
 					return null;