Python: Support iterable unpacking in type-tracking

Author: RasmusWL

python/ql/lib/semmle/python/dataflow/new/internal/DataFlowPrivate.qll

@@ -650,6 +650,8 @@ predicate storeStepCommon(Node nodeFrom, ContentSet c, Node nodeTo) {
   dictStoreStep(nodeFrom, c, nodeTo)
   or
   moreDictStoreSteps(nodeFrom, c, nodeTo)
+  or
+  iterableUnpackingStoreStep(nodeFrom, c, nodeTo)
 }
 
 /**
@@ -665,8 +667,6 @@ predicate storeStep(Node nodeFrom, ContentSet c, Node nodeTo) {
   or
   comprehensionStoreStep(nodeFrom, c, nodeTo)
   or
-  iterableUnpackingStoreStep(nodeFrom, c, nodeTo)
-  or
   attributeStoreStep(nodeFrom, c, nodeTo)
   or
   matchStoreStep(nodeFrom, c, nodeTo)
@@ -903,6 +903,8 @@ predicate attributeStoreStep(Node nodeFrom, AttributeContent c, Node nodeTo) {
  */
 predicate readStepCommon(Node nodeFrom, ContentSet c, Node nodeTo) {
   subscriptReadStep(nodeFrom, c, nodeTo)
+  or
+  iterableUnpackingReadStep(nodeFrom, c, nodeTo)
 }
 
 /**
@@ -911,8 +913,6 @@ predicate readStepCommon(Node nodeFrom, ContentSet c, Node nodeTo) {
 predicate readStep(Node nodeFrom, ContentSet c, Node nodeTo) {
   readStepCommon(nodeFrom, c, nodeTo)
   or
-  iterableUnpackingReadStep(nodeFrom, c, nodeTo)
-  or
   matchReadStep(nodeFrom, c, nodeTo)
   or
   forReadStep(nodeFrom, c, nodeTo)

python/ql/test/experimental/library-tests/CallGraph/InlineCallGraphTest.expected

@@ -15,7 +15,6 @@ pointsTo_found_typeTracker_notFound
 | code/func_defined_outside_class.py:39:11:39:21 | ControlFlowNode for _gen() | B._gen |
 | code/func_defined_outside_class.py:42:1:42:7 | ControlFlowNode for Attribute() | B._gen.func |
 | code/func_defined_outside_class.py:43:1:43:7 | ControlFlowNode for Attribute() | B._gen.func |
-| code/func_ref_in_content.py:20:1:20:4 | ControlFlowNode for f2() | func |
 | code/funky_regression.py:15:9:15:17 | ControlFlowNode for Attribute() | Wat.f2 |
 | code/type_tracking_limitation.py:8:1:8:3 | ControlFlowNode for x() | my_func |
 typeTracker_found_pointsTo_notFound

python/ql/test/experimental/library-tests/CallGraph/code/func_ref_in_content.py

@@ -17,7 +17,7 @@ def return_func_in_tuple():
 tup = return_func_in_tuple() # $ pt,tt=return_func_in_tuple
 
 f2, _ = tup
-f2() # $ pt=func MISSING: tt
+f2() # $ pt,tt=func
 
 f3 = tup[0]
 f3() # $ tt,pt=func