C++: Add test.

cpp/ql/test/library-tests/dataflow/taint-tests/taint.ql

@@ -76,6 +76,24 @@ module AstTest {
 module IRTest {
   private import semmle.code.cpp.ir.IR
   private import semmle.code.cpp.ir.dataflow.TaintTracking
+  private import semmle.code.cpp.ir.dataflow.FlowSteps
+
+  /**
+   * Object->field flow when the object is of type
+   * TaintInheritingContentObject and the field is named
+   * flowFromObject
+   */
+  class TaintInheritingContentTest extends TaintInheritingContent, DataFlow::FieldContent {
+    TaintInheritingContentTest() {
+      exists(Struct o, Field f |
+        this.getField() = f and
+        f = o.getAField() and
+        o.hasGlobalName("TaintInheritingContentObject") and
+        f.hasName("flowFromObject") and
+        this.getIndirectionIndex() = 1
+      )
+    }
+  }
 
   /** Common data flow configuration to be used by tests. */
   module TestAllocationConfig implements DataFlow::ConfigSig {