JS: Deprecate DataFlow::BarrierGuardNode

Author: asgerf

javascript/ql/lib/semmle/javascript/dataflow/Configuration.qll

@@ -367,8 +367,7 @@ abstract private class BarrierGuardNodeInternal extends DataFlow::Node { }
  * classes as precise as possible: if two subclasses of `BarrierGuardNode` overlap, their
  * implementations of `blocks` will _both_ apply to any configuration that includes either of them.
  */
-abstract class BarrierGuardNode extends BarrierGuardNodeInternal {
-  // TODO: deprecate this class; currently requires too much refactoring
+abstract deprecated class BarrierGuardNode extends BarrierGuardNodeInternal {
   /**
    * Holds if this node blocks expression `e` provided it evaluates to `outcome`.
    *

javascript/ql/lib/semmle/javascript/dataflow/internal/BarrierGuards.qll

@@ -63,13 +63,21 @@ module MakeLabeledBarrierGuard<LabeledBarrierGuardSig BaseGuard> {
   }
 }
 
-deprecated private signature predicate isBarrierGuardSig(DataFlow::BarrierGuardNode node);
+/**
+ * Contains deprecated signatures.
+ *
+ * This module is a workaround for the fact that deprecated signatures can't refer to deprecated classes
+ * without getting a deprecation warning
+ */
+deprecated private module DeprecatedSigs {
+  signature predicate isBarrierGuardSig(DataFlow::BarrierGuardNode node);
+}
 
 /**
  * Converts a labeled barrier guard class to a set of nodes to include in an implementation of `isBarrier(node)` and `isBarrier(node, label)`
  * in a `DataFlow::StateConfigSig` implementation.
  */
-deprecated module MakeLegacyBarrierGuardLabeled<isBarrierGuardSig/1 isBarrierGuard> {
+deprecated module MakeLegacyBarrierGuardLabeled<DeprecatedSigs::isBarrierGuardSig/1 isBarrierGuard> {
   final private class FinalNode = DataFlow::Node;
 
   private class Adapter extends FinalNode instanceof DataFlow::BarrierGuardNode {
@@ -100,7 +108,7 @@ deprecated module MakeLegacyBarrierGuardLabeled<isBarrierGuardSig/1 isBarrierGua
 /**
  * Converts a barrier guard class to a set of nodes to include in an implementation of `isBarrier(node)` in a `DataFlow::ConfigSig` implementation.
  */
-deprecated module MakeLegacyBarrierGuard<isBarrierGuardSig/1 isBarrierGuard> {
+deprecated module MakeLegacyBarrierGuard<DeprecatedSigs::isBarrierGuardSig/1 isBarrierGuard> {
   final private class FinalNode = DataFlow::Node;
 
   private class Adapter extends FinalNode instanceof DataFlow::BarrierGuardNode {

javascript/ql/test/library-tests/Barriers/SimpleBarrierGuard.ql

@@ -19,17 +19,20 @@ module TestConfig implements DataFlow::ConfigSig {
 
 module TestFlow = DataFlow::Global<TestConfig>;
 
-class SimpleBarrierGuardNode extends DataFlow::BarrierGuardNode, DataFlow::InvokeNode {
+class SimpleBarrierGuardNode extends DataFlow::InvokeNode {
   SimpleBarrierGuardNode() { this.getCalleeName() = "BARRIER" }
 
-  override predicate blocks(boolean outcome, Expr e) { this.blocksExpr(outcome, e) }
-
   predicate blocksExpr(boolean outcome, Expr e) {
     outcome = true and
     e = this.getArgument(0).asExpr()
   }
 }
 
+deprecated class SimpleBarrierGuardNodeLegacy extends DataFlow::BarrierGuardNode instanceof SimpleBarrierGuardNode
+{
+  override predicate blocks(boolean outcome, Expr e) { super.blocksExpr(outcome, e) }
+}
+
 deprecated class LegacyConfig extends DataFlow::Configuration {
   LegacyConfig() { this = "LegacyConfig" }
 
@@ -38,7 +41,7 @@ deprecated class LegacyConfig extends DataFlow::Configuration {
   override predicate isSink(DataFlow::Node sink) { TestConfig::isSink(sink) }
 
   override predicate isBarrierGuard(DataFlow::BarrierGuardNode guard) {
-    guard instanceof SimpleBarrierGuardNode
+    guard instanceof SimpleBarrierGuardNodeLegacy
   }
 }
 

javascript/ql/test/library-tests/TaintTracking/DataFlowTracking.ql

@@ -22,8 +22,9 @@ class BasicBarrierGuard extends DataFlow::CallNode {
   }
 }
 
-deprecated class BasicBarrierGuardLegacy extends DataFlow::BarrierGuardNode, BasicBarrierGuard {
-  override predicate blocks(boolean outcome, Expr e) { this.blocksExpr(outcome, e) }
+deprecated class BasicBarrierGuardLegacy extends DataFlow::BarrierGuardNode instanceof BasicBarrierGuard
+{
+  override predicate blocks(boolean outcome, Expr e) { super.blocksExpr(outcome, e) }
 }
 
 deprecated class LegacyConfig extends DataFlow::Configuration {