C++/Go/Python/Ruby/Swift: Add dummy localMustFlowStep.

Author: aschackmull

cpp/ql/lib/semmle/code/cpp/dataflow/internal/DataFlowPrivate.qll

@@ -208,6 +208,8 @@ predicate expectsContent(Node n, ContentSet c) { none() }
 
 predicate typeStrongerThan(DataFlowType t1, DataFlowType t2) { none() }
 
+predicate localMustFlowStep(Node node1, Node node2) { none() }
+
 /** Gets the type of `n` used for type pruning. */
 Type getNodeType(Node n) {
   suppressUnusedNode(n) and

cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/DataFlowPrivate.qll

@@ -804,6 +804,8 @@ predicate expectsContent(Node n, ContentSet c) { none() }
 
 predicate typeStrongerThan(DataFlowType t1, DataFlowType t2) { none() }
 
+predicate localMustFlowStep(Node node1, Node node2) { none() }
+
 /** Gets the type of `n` used for type pruning. */
 DataFlowType getNodeType(Node n) {
   suppressUnusedNode(n) and

go/ql/lib/semmle/go/dataflow/internal/DataFlowPrivate.qll

@@ -205,6 +205,8 @@ predicate expectsContent(Node n, ContentSet c) {
 
 predicate typeStrongerThan(DataFlowType t1, DataFlowType t2) { none() }
 
+predicate localMustFlowStep(Node node1, Node node2) { none() }
+
 /** Gets the type of `n` used for type pruning. */
 DataFlowType getNodeType(Node n) { result = TTodoDataFlowType() and exists(n) }
 

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

@@ -539,6 +539,8 @@ predicate compatibleTypes(DataFlowType t1, DataFlowType t2) { any() }
 
 predicate typeStrongerThan(DataFlowType t1, DataFlowType t2) { none() }
 
+predicate localMustFlowStep(Node node1, Node node2) { none() }
+
 /**
  * Gets the type of `node`.
  */

ruby/ql/lib/codeql/ruby/dataflow/internal/DataFlowPrivate.qll

@@ -1697,6 +1697,8 @@ private predicate mustHaveLambdaType(CfgNodes::ExprCfgNode e, Callable c) {
   )
 }
 
+predicate localMustFlowStep(Node node1, Node node2) { none() }
+
 /** Gets the type of `n` used for type pruning. */
 DataFlowType getNodeType(Node n) {
   result = TLambdaDataFlowType(n.(LambdaSelfReferenceNode).getCallable())

swift/ql/lib/codeql/swift/dataflow/internal/DataFlowPrivate.qll

@@ -1038,6 +1038,8 @@ class DataFlowType extends TDataFlowType {
 
 predicate typeStrongerThan(DataFlowType t1, DataFlowType t2) { none() }
 
+predicate localMustFlowStep(Node node1, Node node2) { none() }
+
 /** Gets the type of `n` used for type pruning. */
 DataFlowType getNodeType(Node n) {
   any() // return the singleton DataFlowType until we support type pruning for Swift