C#: Add NullCoalescing example.

michaelnebel · michaelnebel · commit 11d67744f7de · 2022-09-29T11:35:35.000+02:00
diff --git a/csharp/ql/test/library-tests/dataflow/global/GlobalDataFlow.cs b/csharp/ql/test/library-tests/dataflow/global/GlobalDataFlow.cs
@@ -490,7 +490,7 @@ void Inner(Action<string> a, bool b, string arg)
         Inner(_ => { }, b, "taint source");
     }
 
-    private class SimpleClass
+    public class SimpleClass
     {
         public string field = "";
     }
@@ -522,6 +522,14 @@ public void M7()
         TaintField((SimpleClass)x);
         Check(x.field);
     }
+
+    public void M8(SimpleClass x)
+    {
+        var y = new SimpleClass();
+        TaintField(x ?? y);
+        Check(x.field);
+        Check(y.field);
+    }
 }
 
 static class IEnumerableExtensions

Original file line number	Diff line number	Diff line change
`@@ -490,7 +490,7 @@ void Inner(Action<string> a, bool b, string arg)`
`490`	`490`	`Inner(_ => { }, b, "taint source");`
`491`	`491`	`}`
`492`	`492`
`493`		`- private class SimpleClass`
	`493`	`+ public class SimpleClass`
`494`	`494`	`{`
`495`	`495`	`public string field = "";`
`496`	`496`	`}`
`@@ -522,6 +522,14 @@ public void M7()`
`522`	`522`	`TaintField((SimpleClass)x);`
`523`	`523`	`Check(x.field);`
`524`	`524`	`}`
	`525`	`+`
	`526`	`+ public void M8(SimpleClass x)`
	`527`	`+ {`
	`528`	`+ var y = new SimpleClass();`
	`529`	`+ TaintField(x ?? y);`
	`530`	`+ Check(x.field);`
	`531`	`+ Check(y.field);`
	`532`	`+ }`
`525`	`533`	`}`
`526`	`534`
`527`	`535`	`static class IEnumerableExtensions`