C#: Add external flow tests for synthetic fields.

csharp/ql/test/library-tests/dataflow/external-models/ExternalFlow.cs

@@ -291,4 +291,42 @@ namespace My.Qltest
 
         static void Sink(object o) { }
     }
+
+    // Test synthetic fields
+    public class K {
+
+        public object MyField;
+
+        public void SetMySyntheticField(object o) => throw null;
+
+        public object GetMySyntheticField() => throw null;
+
+        public void SetMyNestedSyntheticField(object o) => throw null;
+
+        public object GetMyNestedSyntheticField() => throw null;
+
+        public void SetMyFieldOnSyntheticField(object o) => throw null;
+
+        public object GetMyFieldOnSyntheticField() => throw null;
+
+        public void M1() {
+            var o = new object();
+            SetMySyntheticField(o);
+            Sink(GetMySyntheticField());
+        }
+
+        public void M2() {
+            var o = new object();
+            SetMyNestedSyntheticField(o);
+            Sink(GetMyNestedSyntheticField());
+        }
+
+        public void M3() {
+            var o = new object();
+            SetMyFieldOnSyntheticField(o);
+            Sink(GetMyFieldOnSyntheticField());
+        }
+
+        static void Sink(object o) { }
+    }
 }

csharp/ql/test/library-tests/dataflow/external-models/ExternalFlow.expected

@@ -243,6 +243,14 @@ nodes
 subpaths
 | ExternalFlow.cs:84:29:84:32 | access to local variable objs : null [element] : Object | ExternalFlow.cs:84:35:84:35 | o : Object | ExternalFlow.cs:84:40:84:40 | access to parameter o : Object | ExternalFlow.cs:84:25:84:41 | call to method Map<Object,Object> : T[] [element] : Object |
 invalidModelRow
+| Unrecognized input specification "SyntheticField[My.Qltest.K.MySyntheticField1]" in summary model. |
+| Unrecognized input specification "SyntheticField[My.Qltest.K.MySyntheticField2]" in summary model. |
+| Unrecognized input specification "SyntheticField[My.Qltest.K.MySyntheticField]" in summary model. |
+| Unrecognized input specification "SyntheticField[MySyntheticField1.MyNestedSyntheticField]" in summary model. |
+| Unrecognized output specification "SyntheticField[My.Qltest.K.MySyntheticField1]" in summary model. |
+| Unrecognized output specification "SyntheticField[My.Qltest.K.MySyntheticField2]" in summary model. |
+| Unrecognized output specification "SyntheticField[My.Qltest.K.MySyntheticField]" in summary model. |
+| Unrecognized output specification "SyntheticField[MySyntheticField1.MyNestedSyntheticField]" in summary model. |
 #select
 | ExternalFlow.cs:10:18:10:33 | call to method StepArgRes | ExternalFlow.cs:9:27:9:38 | object creation of type Object : Object | ExternalFlow.cs:10:18:10:33 | call to method StepArgRes | $@ | ExternalFlow.cs:9:27:9:38 | object creation of type Object : Object | object creation of type Object : Object |
 | ExternalFlow.cs:18:18:18:24 | access to local variable argOut1 | ExternalFlow.cs:15:29:15:40 | object creation of type Object : Object | ExternalFlow.cs:18:18:18:24 | access to local variable argOut1 | $@ | ExternalFlow.cs:15:29:15:40 | object creation of type Object : Object | object creation of type Object : Object |

csharp/ql/test/library-tests/dataflow/external-models/ExternalFlow.ext.yml

@@ -37,6 +37,13 @@ extensions:
       - ["My.Qltest", "J", false, "SetProp1", "(System.Object)", "", "Argument[0]", "Argument[this]", "value", "manual"]
       - ["My.Qltest", "J", false, "get_Prop2", "()", "", "Argument[this]", "ReturnValue", "value", "df-generated"]
       - ["My.Qltest", "J", false, "SetProp2", "(System.Object)", "", "Argument[0]", "Argument[this]", "value", "manual"]
+      - ["My.Qltest", "K", false, "SetMySyntheticField", "(System.Object)", "", "Argument[0]", "Argument[this].SyntheticField[My.Qltest.K.MySyntheticField]", "value", "manual"]
+      - ["My.Qltest", "K", false, "GetMySyntheticField", "()", "", "Argument[this].SyntheticField[My.Qltest.K.MySyntheticField]", "ReturnValue", "value", "manual"]
+      - ["My.Qltest", "K", false, "SetMyNestedSyntheticField", "(System.Object)", "", "Argument[0]", "Argument[this].SyntheticField[My.Qltest.K.MySyntheticField1].SyntheticField[MySyntheticField1.MyNestedSyntheticField]", "value", "manual"]
+      - ["My.Qltest", "K", false, "GetMyNestedSyntheticField", "()", "", "Argument[this].SyntheticField[My.Qltest.K.MySyntheticField1].SyntheticField[MySyntheticField1.MyNestedSyntheticField]", "ReturnValue", "value", "manual"]
+      - ["My.Qltest", "K", false, "SetMyFieldOnSyntheticField", "(System.Object)", "", "Argument[0]", "Argument[this].SyntheticField[My.Qltest.K.MySyntheticField2].Field[My.Qltest.K.MyField]", "value", "manual"]
+      - ["My.Qltest", "K", false, "GetMyFieldOnSyntheticField", "()", "", "Argument[this].SyntheticField[My.Qltest.K.MySyntheticField2].Field[My.Qltest.K.MyField]", "ReturnValue", "value", "manual"]
+
   - addsTo:
       pack: codeql/csharp-all
       extensible: neutralModel