C#: Add tests for missing reverse flow

Author: hvitved

csharp/ql/test/library-tests/dataflow/reverse-flow/ReverseFlow.cs

@@ -0,0 +1,89 @@
+public class A
+{
+    public string Field;
+
+    public A Nested;
+
+    public void M1()
+    {
+        var a = new A();
+        M2(a);
+        Sink(a.Nested.Field); // $ MISSING: hasValueFlow=1
+    }
+
+    public void M2(A a)
+    {
+        var b = a.Nested;
+        M3(b);
+    }
+
+    public void M3(A a)
+    {
+        a.Field = Source<string>(1);
+    }
+
+    public void M4()
+    {
+        this.M5();
+        Sink(this.Nested.Field); // $ MISSING: hasValueFlow=2
+    }
+
+    public void M5()
+    {
+        var b = this.Nested;
+        b.M6();
+    }
+
+    public void M6()
+    {
+        this.Field = Source<string>(2);
+    }
+
+    public void M7()
+    {
+        var a = new A();
+        M8(a);
+        Sink(a.Field); // $ MISSING: hasValueFlow=3
+    }
+
+    public void M8(A a)
+    {
+        var b = new A();
+        b.Nested = a;
+        M9(b);
+    }
+
+    public void M9(A a)
+    {
+        a.Nested.Field = Source<string>(3);
+    }
+
+    public void M10()
+    {
+        var a = new A();
+        Sink(a);
+        Sink(a.Nested.Nested.Field);
+        GetNestedNested(a).Field = Source<string>(4);
+        Sink(a.Nested.Nested.Field); // $ MISSING: hasValueFlow=4
+    }
+
+    public void M11(A a)
+    {
+
+    }
+
+    public void M12()
+    {
+        var a = new A();
+        M11(a);
+        Sink(a.Field);
+        a.Field = Source<string>(5);
+        Sink(a.Field); // $ hasValueFlow=5
+    }
+
+    public A GetNestedNested(A a) => a.Nested.Nested;
+
+    public static void Sink(object o) { }
+
+    static T Source<T>(object source) => throw null;
+}

csharp/ql/test/library-tests/dataflow/reverse-flow/ReverseFlow.expected

@@ -0,0 +1,22 @@
+models
+edges
+| ReverseFlow.cs:80:9:80:9 | [post] access to local variable a : A [field Field] : String | ReverseFlow.cs:81:14:81:14 | access to local variable a : A [field Field] : String | provenance |  |
+| ReverseFlow.cs:80:9:80:9 | [post] access to local variable a : A [field Field] : String | ReverseFlow.cs:81:14:81:14 | access to local variable a : A [field Field] : String | provenance |  |
+| ReverseFlow.cs:80:19:80:35 | call to method Source<String> : String | ReverseFlow.cs:80:9:80:9 | [post] access to local variable a : A [field Field] : String | provenance |  |
+| ReverseFlow.cs:80:19:80:35 | call to method Source<String> : String | ReverseFlow.cs:80:9:80:9 | [post] access to local variable a : A [field Field] : String | provenance |  |
+| ReverseFlow.cs:81:14:81:14 | access to local variable a : A [field Field] : String | ReverseFlow.cs:81:14:81:20 | access to field Field | provenance |  |
+| ReverseFlow.cs:81:14:81:14 | access to local variable a : A [field Field] : String | ReverseFlow.cs:81:14:81:20 | access to field Field | provenance |  |
+nodes
+| ReverseFlow.cs:80:9:80:9 | [post] access to local variable a : A [field Field] : String | semmle.label | [post] access to local variable a : A [field Field] : String |
+| ReverseFlow.cs:80:9:80:9 | [post] access to local variable a : A [field Field] : String | semmle.label | [post] access to local variable a : A [field Field] : String |
+| ReverseFlow.cs:80:19:80:35 | call to method Source<String> : String | semmle.label | call to method Source<String> : String |
+| ReverseFlow.cs:80:19:80:35 | call to method Source<String> : String | semmle.label | call to method Source<String> : String |
+| ReverseFlow.cs:81:14:81:14 | access to local variable a : A [field Field] : String | semmle.label | access to local variable a : A [field Field] : String |
+| ReverseFlow.cs:81:14:81:14 | access to local variable a : A [field Field] : String | semmle.label | access to local variable a : A [field Field] : String |
+| ReverseFlow.cs:81:14:81:20 | access to field Field | semmle.label | access to field Field |
+| ReverseFlow.cs:81:14:81:20 | access to field Field | semmle.label | access to field Field |
+subpaths
+testFailures
+#select
+| ReverseFlow.cs:81:14:81:20 | access to field Field | ReverseFlow.cs:80:19:80:35 | call to method Source<String> : String | ReverseFlow.cs:81:14:81:20 | access to field Field | $@ | ReverseFlow.cs:80:19:80:35 | call to method Source<String> : String | call to method Source<String> : String |
+| ReverseFlow.cs:81:14:81:20 | access to field Field | ReverseFlow.cs:80:19:80:35 | call to method Source<String> : String | ReverseFlow.cs:81:14:81:20 | access to field Field | $@ | ReverseFlow.cs:80:19:80:35 | call to method Source<String> : String | call to method Source<String> : String |

csharp/ql/test/library-tests/dataflow/reverse-flow/ReverseFlow.ql

@@ -0,0 +1,12 @@
+/**
+ * @kind path-problem
+ */
+
+import csharp
+import TestUtilities.InlineFlowTest
+import DefaultFlowTest
+import PathGraph
+
+from PathNode source, PathNode sink
+where flowPath(source, sink)
+select sink, source, sink, "$@", source, source.toString()