C#: Add some test cases for excluding methods for model generation.

Author: michaelnebel

csharp/ql/test/utils/modelgenerator/dataflow/CaptureNeutralModels.ext.yml

@@ -0,0 +1,6 @@
+extensions:
+  - addsTo:
+      pack: codeql/csharp-all
+      extensible: neutralModel
+    data:
+      - [ "NoSummaries", "ManuallyModelled", "HasNeutralSummaryNoFlow", "(System.Object)", "summary", "manual"]

csharp/ql/test/utils/modelgenerator/dataflow/CaptureSummaryModels.ext.yml

@@ -0,0 +1,12 @@
+extensions:
+  - addsTo:
+      pack: codeql/csharp-all
+      extensible: summaryModel
+    data:
+      - [ "NoSummaries", "ManuallyModelled", False, "HasSummary", "(System.Object)", "", "Argument[0]", "ReturnValue", "value", "manual"]
+
+  - addsTo:
+      pack: codeql/csharp-all
+      extensible: neutralModel
+    data:
+      - [ "NoSummaries", "ManuallyModelled", "HasNeutralSummary", "(System.Object)", "summary", "manual"]

csharp/ql/test/utils/modelgenerator/dataflow/NoSummaries.cs

@@ -143,3 +143,22 @@ public ParameterlessConstructor()
         IsInitialized = true;
     }
 }
+
+// No models should be created, if there exist either a manual summary or neutral summary.
+public class ManuallyModelled
+{
+    public object HasSummary(object o)
+    {
+        return o;
+    }
+
+    public object HasNeutralSummary(object o)
+    {
+        return o;
+    }
+
+    public object HasNeutralSummaryNoFlow(object o)
+    {
+        return null;
+    }
+}