PS: Add intermediate api graph nodes for 'New-Object' calls similar to what we have for type name expressions.

Author: MathiasVP

powershell/ql/lib/semmle/code/powershell/ApiGraphs.qll

@@ -369,7 +369,7 @@ module API {
 
     final predicate isImplicit() { not this.isExplicit(_) }
 
-    predicate isExplicit(DataFlow::TypeNameNode typeName) { none() }
+    predicate isExplicit(DataFlow::Node node) { none() }
   }
 
   final class TypeNameNode = AbstractTypeNameNode;
@@ -392,8 +392,8 @@ module API {
       )
     }
 
-    final override predicate isExplicit(DataFlow::TypeNameNode typeName) {
-      Specific::needsExplicitTypeNameNode(typeName, prefix)
+    final override predicate isExplicit(DataFlow::Node node) {
+      Specific::needsExplicitTypeNameNode(node, prefix)
     }
   }
 
@@ -424,6 +424,18 @@ module API {
     }
   }
 
+  class NewObjectTypeNameNode extends AbstractTypeNameNode, Impl::MkNewObjectTypeNameNode {
+    NewObjectTypeNameNode() { this = Impl::MkNewObjectTypeNameNode(prefix) }
+
+    final override Node getSuccessor(string name) {
+      result = Impl::MkNewObjectTypeNameNode(prefix + "." + name)
+    }
+
+    final override predicate isExplicit(DataFlow::Node node) {
+      Specific::needsNewObjectTypeNameNode(node, prefix)
+    }
+  }
+
   /**
    * An API entry point.
    *
@@ -517,6 +529,7 @@ module API {
       MkMethodAccessNode(DataFlow::CallNode call) or
       MkExplicitTypeNameNode(string prefix) { Specific::needsExplicitTypeNameNode(_, prefix) } or
       MkImplicitTypeNameNode(string prefix) { Specific::needsImplicitTypeNameNode(prefix) } or
+      MkNewObjectTypeNameNode(string prefix) { Specific::needsNewObjectTypeNameNode(_, prefix) } or
       MkForwardNode(DataFlow::LocalSourceNode node, TypeTracker t) { isReachable(node, t) } or
       /** Intermediate node for following backward data flow. */
       MkBackwardNode(DataFlow::LocalSourceNode node, TypeTracker t) { isReachable(node, t) } or

powershell/ql/lib/semmle/code/powershell/frameworks/data/internal/ApiGraphModelsSpecific.qll

@@ -101,6 +101,16 @@ predicate needsImplicitTypeNameNode(string component) {
   )
 }
 
+predicate needsNewObjectTypeNameNode(DataFlow::ObjectCreationNode creation, string component) {
+  creation.asExpr().getExpr() instanceof DotNetObjectCreation and
+  exists(string type, int index |
+    type = creation.getLowerCaseConstructedTypeName() and
+    index = [0 .. strictcount(type.indexOf("."))] and
+    component =
+      strictconcat(int i, string s | s = type.splitAt(".", i) and i <= index | s, "." order by i)
+  )
+}
+
 /** Gets a Powershell-specific interpretation of the given `type`. */
 API::Node getExtraNodeFromType(string rawType) {
   exists(string type, string suffix, DataFlow::TypeNameNode typeName |