Python: override genEnclosingCallable

achieved flow out of functions!

python/ql/src/experimental/dataflow/internal/DataFlowPrivate.qll

@@ -122,11 +122,19 @@ class ReturnKind extends TReturnKind {
 
 /** A data flow node that represents a value returned by a callable. */
 class ReturnNode extends Node {
+  Return ret;
+
   // See `TaintTrackingImplementation::returnFlowStep`
-  ReturnNode() { this.asCfgNode() = any(Return r).getValue().getAFlowNode() }
+  ReturnNode() {
+    this.asCfgNode() = ret.getValue().getAFlowNode()
+  }
 
   /** Gets the kind of this return node. */
   ReturnKind getKind() { result = TNormalReturnKind() }
+
+  override DataFlowCallable getEnclosingCallable() {
+    result.getScope().getAStmt() = ret // TODO: check nested function definitions
+  }
 }
 
 /** A data flow node that represents the output of a call. */

python/ql/src/experimental/dataflow/internal/DataFlowPublic.qll

@@ -48,7 +48,7 @@ class Node extends TNode {
   }
 
   /** Gets the enclosing callable of this node. */
-  final DataFlowCallable getEnclosingCallable() {
+  DataFlowCallable getEnclosingCallable() {
     none()
   }
 
@@ -99,13 +99,17 @@ class ParameterNode extends Node {
     this.asEssaNode() instanceof ParameterDefinition
   }
 
-    /**
+  /**
    * Holds if this node is the parameter of callable `c` at the specified
    * (zero-based) position.
    */
   predicate isParameterOf(DataFlowCallable c, int i) {
     this.asEssaNode().(ParameterDefinition).getDefiningNode() = c.getParameter(i)
   }
+
+  override DataFlowCallable getEnclosingCallable() {
+    this.isParameterOf(result, _)
+  }
 }
 
 /**

python/ql/test/experimental/dataflow/callGraph.expected

@@ -0,0 +1 @@
+| test.py:4:10:4:10 | ControlFlowNode for z | test.py:7:5:7:20 | ControlFlowNode for obfuscated_id() |