C#: Add some lambda flow tests for demo

csharp/ql/test/library-tests/dataflow/lambda/LambdaFlow.cs

@@ -0,0 +1,190 @@
+using System;
+
+public class LambdaFlow
+{
+    /// <summary>
+    /// Flow into a normal method
+    /// </summary>
+    class Ex1
+    {
+        void M1(string s)
+        {
+            Sink(s); // $ hasValueFlow=1
+        }
+
+        public void M2()
+        {
+            var source = Source(1);
+            M1(source);
+        }
+    }
+
+
+
+
+
+
+
+    /// <summary>
+    /// Flow into a lambda
+    /// </summary>
+    class Ex2
+    {
+        void M1(Action<string> lambda)
+        {
+            var source = Source(2);
+            lambda(source);
+        }
+
+        void M2()
+        {
+            Action<string> lambda = x => Sink(x); // $ hasValueFlow=2
+            M1(lambda);
+        }
+    }
+
+
+
+
+
+
+
+    /// <summary>
+    /// Flow out of a lambda
+    /// </summary>
+    class Ex3
+    {
+        Func<string> M1()
+        {
+            return () => Source(3);
+        }
+
+        void M2()
+        {
+            var lambda = M1();
+            Sink(lambda()); // $ hasValueFlow=3
+        }
+    }
+
+
+
+
+
+
+
+    /// <summary>
+    /// Flow through a lambda
+    /// </summary>
+    class Ex4
+    {
+        string M1(Func<string, string> lambda, string input)
+        {
+            return lambda(input);
+        }
+
+        void M2()
+        {
+            Func<string, string> id = x => x;
+            var source = Source(4);
+            var output = M1(id, source);
+            Sink(output); // $ hasValueFlow=4
+        }
+    }
+
+
+
+
+
+
+
+    /// <summary>
+    /// No flow into lambda (call context sensitivity)
+    /// </summary>
+    class Ex5
+    {
+        void M1(Action<string> lambda, string input)
+        {
+            lambda(input);
+        }
+
+        void M2(Action<string> lambda, string input)
+        {
+            M1(lambda, input);
+        }
+
+        void M3()
+        {
+            Action<string> lambda1 = arg => Sink(arg);
+            Action<string> lambda2 = arg => { };
+
+            var source = Source(5);
+            var nonSource = "non-source";
+
+            M1(lambda1, nonSource);
+            M1(lambda2, source);
+
+            M2(lambda1, nonSource);
+            M2(lambda2, source);
+        }
+    }
+
+
+
+
+
+
+
+    /// <summary>
+    /// Flow into a returned lambda
+    /// </summary>
+    class Ex6
+    {
+        Action<string> M1()
+        {
+            return x => Sink(x); // $ hasValueFlow=6
+        }
+
+        void M2()
+        {
+            var source = Source(6);
+            var lambda = M1();
+            lambda(source);
+        }
+    }
+
+
+
+
+
+
+
+    /// <summary>
+    /// No flow through lambda
+    /// </summary>
+    class Ex7
+    {
+        void M1(Func<string, string> lambda)
+        {
+            var source = Source(7);
+            lambda(source);
+        }
+
+        void M2(Func<string, string> lambda)
+        {
+            var nonSource = "non-source";
+            var output = lambda(nonSource);
+            Sink(output);
+        }
+
+        void M3()
+        {
+            Func<string, string> id = x => x;
+            M1(id);
+            M2(id);
+        }
+    }
+
+    static string Source(int source) => source.ToString();
+
+    static void Sink(string value) { }
+}

csharp/ql/test/library-tests/dataflow/lambda/LambdaFlow.expected

@@ -0,0 +1,120 @@
+models
+edges
+| LambdaFlow.cs:10:24:10:24 | s : String | LambdaFlow.cs:12:18:12:18 | access to parameter s | provenance |  |
+| LambdaFlow.cs:17:17:17:22 | access to local variable source : String | LambdaFlow.cs:18:16:18:21 | access to local variable source : String | provenance |  |
+| LambdaFlow.cs:17:26:17:34 | call to method Source : String | LambdaFlow.cs:17:17:17:22 | access to local variable source : String | provenance |  |
+| LambdaFlow.cs:18:16:18:21 | access to local variable source : String | LambdaFlow.cs:10:24:10:24 | s : String | provenance |  |
+| LambdaFlow.cs:33:32:33:37 | lambda [Return] : Action<String> [delegate argument at position 0] : String | LambdaFlow.cs:42:16:42:21 | [post] access to local variable lambda : Action<String> [delegate argument at position 0] : String | provenance |  |
+| LambdaFlow.cs:35:17:35:22 | access to local variable source : String | LambdaFlow.cs:36:20:36:25 | access to local variable source : String | provenance |  |
+| LambdaFlow.cs:35:26:35:34 | call to method Source : String | LambdaFlow.cs:35:17:35:22 | access to local variable source : String | provenance |  |
+| LambdaFlow.cs:36:13:36:18 | [post] access to parameter lambda : Action<String> [delegate argument at position 0] : String | LambdaFlow.cs:33:32:33:37 | lambda [Return] : Action<String> [delegate argument at position 0] : String | provenance |  |
+| LambdaFlow.cs:36:20:36:25 | access to local variable source : String | LambdaFlow.cs:36:13:36:18 | [post] access to parameter lambda : Action<String> [delegate argument at position 0] : String | provenance |  |
+| LambdaFlow.cs:41:37:41:37 | x : String | LambdaFlow.cs:41:47:41:47 | access to parameter x | provenance |  |
+| LambdaFlow.cs:42:16:42:21 | [post] access to local variable lambda : Action<String> [delegate argument at position 0] : String | LambdaFlow.cs:41:37:41:37 | x : String | provenance |  |
+| LambdaFlow.cs:59:20:59:34 | (...) => ... : (...) => ... [delegate return] : String | LambdaFlow.cs:64:26:64:29 | call to method M1 : (...) => ... [delegate return] : String | provenance |  |
+| LambdaFlow.cs:59:26:59:34 | call to method Source : String | LambdaFlow.cs:59:20:59:34 | (...) => ... : (...) => ... [delegate return] : String | provenance |  |
+| LambdaFlow.cs:64:17:64:22 | access to local variable lambda : (...) => ... [delegate return] : String | LambdaFlow.cs:65:18:65:23 | access to local variable lambda : (...) => ... [delegate return] : String | provenance |  |
+| LambdaFlow.cs:64:26:64:29 | call to method M1 : (...) => ... [delegate return] : String | LambdaFlow.cs:64:17:64:22 | access to local variable lambda : (...) => ... [delegate return] : String | provenance |  |
+| LambdaFlow.cs:65:18:65:23 | access to local variable lambda : (...) => ... [delegate return] : String | LambdaFlow.cs:65:18:65:25 | delegate call | provenance |  |
+| LambdaFlow.cs:80:40:80:45 | lambda : (...) => ... [delegate return] : String | LambdaFlow.cs:82:20:82:25 | access to parameter lambda : (...) => ... [delegate return] : String | provenance |  |
+| LambdaFlow.cs:80:55:80:59 | input : String | LambdaFlow.cs:82:27:82:31 | access to parameter input : String | provenance |  |
+| LambdaFlow.cs:82:20:82:25 | [post] access to parameter lambda : Func<String,String> [delegate argument at position 0] : String | LambdaFlow.cs:80:40:80:45 | lambda [Return] : Func<String,String> [delegate argument at position 0] : String | provenance |  |
+| LambdaFlow.cs:82:20:82:25 | access to parameter lambda : (...) => ... [delegate return] : String | LambdaFlow.cs:82:20:82:32 | delegate call : String | provenance |  |
+| LambdaFlow.cs:82:27:82:31 | access to parameter input : String | LambdaFlow.cs:82:20:82:25 | [post] access to parameter lambda : Func<String,String> [delegate argument at position 0] : String | provenance |  |
+| LambdaFlow.cs:87:34:87:35 | access to local variable id : (...) => ... [delegate return] : String | LambdaFlow.cs:89:29:89:30 | access to local variable id : (...) => ... [delegate return] : String | provenance |  |
+| LambdaFlow.cs:87:39:87:39 | x : String | LambdaFlow.cs:87:44:87:44 | access to parameter x : String | provenance |  |
+| LambdaFlow.cs:87:39:87:44 | (...) => ... : (...) => ... [delegate return] : String | LambdaFlow.cs:87:34:87:35 | access to local variable id : (...) => ... [delegate return] : String | provenance |  |
+| LambdaFlow.cs:88:17:88:22 | access to local variable source : String | LambdaFlow.cs:89:33:89:38 | access to local variable source : String | provenance |  |
+| LambdaFlow.cs:88:26:88:34 | call to method Source : String | LambdaFlow.cs:88:17:88:22 | access to local variable source : String | provenance |  |
+| LambdaFlow.cs:89:17:89:22 | access to local variable output : String | LambdaFlow.cs:90:18:90:23 | access to local variable output | provenance |  |
+| LambdaFlow.cs:89:26:89:39 | call to method M1 : String | LambdaFlow.cs:89:17:89:22 | access to local variable output : String | provenance |  |
+| LambdaFlow.cs:89:29:89:30 | [post] access to local variable id : Func<String,String> [delegate argument at position 0] : String | LambdaFlow.cs:87:39:87:39 | x : String | provenance |  |
+| LambdaFlow.cs:89:29:89:30 | [post] access to local variable id : Func<String,String> [delegate argument at position 0] : String | LambdaFlow.cs:87:39:87:44 | (...) => ... : (...) => ... [delegate return] : String | provenance |  |
+| LambdaFlow.cs:89:29:89:30 | access to local variable id : (...) => ... [delegate return] : String | LambdaFlow.cs:80:40:80:45 | lambda : (...) => ... [delegate return] : String | provenance |  |
+| LambdaFlow.cs:89:29:89:30 | access to local variable id : (...) => ... [delegate return] : String | LambdaFlow.cs:89:26:89:39 | call to method M1 : String | provenance |  |
+| LambdaFlow.cs:89:33:89:38 | access to local variable source : String | LambdaFlow.cs:80:55:80:59 | input : String | provenance |  |
+| LambdaFlow.cs:89:33:89:38 | access to local variable source : String | LambdaFlow.cs:89:29:89:30 | [post] access to local variable id : Func<String,String> [delegate argument at position 0] : String | provenance |  |
+| LambdaFlow.cs:166:38:166:43 | lambda [Return] : Func<String,String> [delegate argument at position 0] : String | LambdaFlow.cs:182:16:182:17 | [post] access to local variable id : Func<String,String> [delegate argument at position 0] : String | provenance |  |
+| LambdaFlow.cs:168:17:168:22 | access to local variable source : String | LambdaFlow.cs:169:20:169:25 | access to local variable source : String | provenance |  |
+| LambdaFlow.cs:168:26:168:34 | call to method Source : String | LambdaFlow.cs:168:17:168:22 | access to local variable source : String | provenance |  |
+| LambdaFlow.cs:169:13:169:18 | [post] access to parameter lambda : Func<String,String> [delegate argument at position 0] : String | LambdaFlow.cs:166:38:166:43 | lambda [Return] : Func<String,String> [delegate argument at position 0] : String | provenance |  |
+| LambdaFlow.cs:169:20:169:25 | access to local variable source : String | LambdaFlow.cs:169:13:169:18 | [post] access to parameter lambda : Func<String,String> [delegate argument at position 0] : String | provenance |  |
+| LambdaFlow.cs:172:38:172:43 | lambda : (...) => ... [delegate return] : String | LambdaFlow.cs:175:26:175:31 | access to parameter lambda : (...) => ... [delegate return] : String | provenance |  |
+| LambdaFlow.cs:175:17:175:22 | access to local variable output : String | LambdaFlow.cs:176:18:176:23 | access to local variable output | provenance |  |
+| LambdaFlow.cs:175:26:175:31 | access to parameter lambda : (...) => ... [delegate return] : String | LambdaFlow.cs:175:26:175:42 | delegate call : String | provenance |  |
+| LambdaFlow.cs:175:26:175:42 | delegate call : String | LambdaFlow.cs:175:17:175:22 | access to local variable output : String | provenance |  |
+| LambdaFlow.cs:181:34:181:35 | access to local variable id : (...) => ... [delegate return] : String | LambdaFlow.cs:183:16:183:17 | access to local variable id : (...) => ... [delegate return] : String | provenance |  |
+| LambdaFlow.cs:181:39:181:39 | x : String | LambdaFlow.cs:181:44:181:44 | access to parameter x : String | provenance |  |
+| LambdaFlow.cs:181:39:181:44 | (...) => ... : (...) => ... [delegate return] : String | LambdaFlow.cs:181:34:181:35 | access to local variable id : (...) => ... [delegate return] : String | provenance |  |
+| LambdaFlow.cs:182:16:182:17 | [post] access to local variable id : Func<String,String> [delegate argument at position 0] : String | LambdaFlow.cs:181:39:181:39 | x : String | provenance |  |
+| LambdaFlow.cs:182:16:182:17 | [post] access to local variable id : Func<String,String> [delegate argument at position 0] : String | LambdaFlow.cs:181:39:181:44 | (...) => ... : (...) => ... [delegate return] : String | provenance |  |
+| LambdaFlow.cs:183:16:183:17 | access to local variable id : (...) => ... [delegate return] : String | LambdaFlow.cs:172:38:172:43 | lambda : (...) => ... [delegate return] : String | provenance |  |
+nodes
+| LambdaFlow.cs:10:24:10:24 | s : String | semmle.label | s : String |
+| LambdaFlow.cs:12:18:12:18 | access to parameter s | semmle.label | access to parameter s |
+| LambdaFlow.cs:17:17:17:22 | access to local variable source : String | semmle.label | access to local variable source : String |
+| LambdaFlow.cs:17:26:17:34 | call to method Source : String | semmle.label | call to method Source : String |
+| LambdaFlow.cs:18:16:18:21 | access to local variable source : String | semmle.label | access to local variable source : String |
+| LambdaFlow.cs:33:32:33:37 | lambda [Return] : Action<String> [delegate argument at position 0] : String | semmle.label | lambda [Return] : Action<String> [delegate argument at position 0] : String |
+| LambdaFlow.cs:35:17:35:22 | access to local variable source : String | semmle.label | access to local variable source : String |
+| LambdaFlow.cs:35:26:35:34 | call to method Source : String | semmle.label | call to method Source : String |
+| LambdaFlow.cs:36:13:36:18 | [post] access to parameter lambda : Action<String> [delegate argument at position 0] : String | semmle.label | [post] access to parameter lambda : Action<String> [delegate argument at position 0] : String |
+| LambdaFlow.cs:36:20:36:25 | access to local variable source : String | semmle.label | access to local variable source : String |
+| LambdaFlow.cs:41:37:41:37 | x : String | semmle.label | x : String |
+| LambdaFlow.cs:41:47:41:47 | access to parameter x | semmle.label | access to parameter x |
+| LambdaFlow.cs:42:16:42:21 | [post] access to local variable lambda : Action<String> [delegate argument at position 0] : String | semmle.label | [post] access to local variable lambda : Action<String> [delegate argument at position 0] : String |
+| LambdaFlow.cs:59:20:59:34 | (...) => ... : (...) => ... [delegate return] : String | semmle.label | (...) => ... : (...) => ... [delegate return] : String |
+| LambdaFlow.cs:59:26:59:34 | call to method Source : String | semmle.label | call to method Source : String |
+| LambdaFlow.cs:64:17:64:22 | access to local variable lambda : (...) => ... [delegate return] : String | semmle.label | access to local variable lambda : (...) => ... [delegate return] : String |
+| LambdaFlow.cs:64:26:64:29 | call to method M1 : (...) => ... [delegate return] : String | semmle.label | call to method M1 : (...) => ... [delegate return] : String |
+| LambdaFlow.cs:65:18:65:23 | access to local variable lambda : (...) => ... [delegate return] : String | semmle.label | access to local variable lambda : (...) => ... [delegate return] : String |
+| LambdaFlow.cs:65:18:65:25 | delegate call | semmle.label | delegate call |
+| LambdaFlow.cs:80:40:80:45 | lambda : (...) => ... [delegate return] : String | semmle.label | lambda : (...) => ... [delegate return] : String |
+| LambdaFlow.cs:80:40:80:45 | lambda [Return] : Func<String,String> [delegate argument at position 0] : String | semmle.label | lambda [Return] : Func<String,String> [delegate argument at position 0] : String |
+| LambdaFlow.cs:80:55:80:59 | input : String | semmle.label | input : String |
+| LambdaFlow.cs:82:20:82:25 | [post] access to parameter lambda : Func<String,String> [delegate argument at position 0] : String | semmle.label | [post] access to parameter lambda : Func<String,String> [delegate argument at position 0] : String |
+| LambdaFlow.cs:82:20:82:25 | access to parameter lambda : (...) => ... [delegate return] : String | semmle.label | access to parameter lambda : (...) => ... [delegate return] : String |
+| LambdaFlow.cs:82:20:82:32 | delegate call : String | semmle.label | delegate call : String |
+| LambdaFlow.cs:82:27:82:31 | access to parameter input : String | semmle.label | access to parameter input : String |
+| LambdaFlow.cs:87:34:87:35 | access to local variable id : (...) => ... [delegate return] : String | semmle.label | access to local variable id : (...) => ... [delegate return] : String |
+| LambdaFlow.cs:87:39:87:39 | x : String | semmle.label | x : String |
+| LambdaFlow.cs:87:39:87:44 | (...) => ... : (...) => ... [delegate return] : String | semmle.label | (...) => ... : (...) => ... [delegate return] : String |
+| LambdaFlow.cs:87:44:87:44 | access to parameter x : String | semmle.label | access to parameter x : String |
+| LambdaFlow.cs:88:17:88:22 | access to local variable source : String | semmle.label | access to local variable source : String |
+| LambdaFlow.cs:88:26:88:34 | call to method Source : String | semmle.label | call to method Source : String |
+| LambdaFlow.cs:89:17:89:22 | access to local variable output : String | semmle.label | access to local variable output : String |
+| LambdaFlow.cs:89:26:89:39 | call to method M1 : String | semmle.label | call to method M1 : String |
+| LambdaFlow.cs:89:29:89:30 | [post] access to local variable id : Func<String,String> [delegate argument at position 0] : String | semmle.label | [post] access to local variable id : Func<String,String> [delegate argument at position 0] : String |
+| LambdaFlow.cs:89:29:89:30 | access to local variable id : (...) => ... [delegate return] : String | semmle.label | access to local variable id : (...) => ... [delegate return] : String |
+| LambdaFlow.cs:89:33:89:38 | access to local variable source : String | semmle.label | access to local variable source : String |
+| LambdaFlow.cs:90:18:90:23 | access to local variable output | semmle.label | access to local variable output |
+| LambdaFlow.cs:166:38:166:43 | lambda [Return] : Func<String,String> [delegate argument at position 0] : String | semmle.label | lambda [Return] : Func<String,String> [delegate argument at position 0] : String |
+| LambdaFlow.cs:168:17:168:22 | access to local variable source : String | semmle.label | access to local variable source : String |
+| LambdaFlow.cs:168:26:168:34 | call to method Source : String | semmle.label | call to method Source : String |
+| LambdaFlow.cs:169:13:169:18 | [post] access to parameter lambda : Func<String,String> [delegate argument at position 0] : String | semmle.label | [post] access to parameter lambda : Func<String,String> [delegate argument at position 0] : String |
+| LambdaFlow.cs:169:20:169:25 | access to local variable source : String | semmle.label | access to local variable source : String |
+| LambdaFlow.cs:172:38:172:43 | lambda : (...) => ... [delegate return] : String | semmle.label | lambda : (...) => ... [delegate return] : String |
+| LambdaFlow.cs:175:17:175:22 | access to local variable output : String | semmle.label | access to local variable output : String |
+| LambdaFlow.cs:175:26:175:31 | access to parameter lambda : (...) => ... [delegate return] : String | semmle.label | access to parameter lambda : (...) => ... [delegate return] : String |
+| LambdaFlow.cs:175:26:175:42 | delegate call : String | semmle.label | delegate call : String |
+| LambdaFlow.cs:176:18:176:23 | access to local variable output | semmle.label | access to local variable output |
+| LambdaFlow.cs:181:34:181:35 | access to local variable id : (...) => ... [delegate return] : String | semmle.label | access to local variable id : (...) => ... [delegate return] : String |
+| LambdaFlow.cs:181:39:181:39 | x : String | semmle.label | x : String |
+| LambdaFlow.cs:181:39:181:44 | (...) => ... : (...) => ... [delegate return] : String | semmle.label | (...) => ... : (...) => ... [delegate return] : String |
+| LambdaFlow.cs:181:44:181:44 | access to parameter x : String | semmle.label | access to parameter x : String |
+| LambdaFlow.cs:182:16:182:17 | [post] access to local variable id : Func<String,String> [delegate argument at position 0] : String | semmle.label | [post] access to local variable id : Func<String,String> [delegate argument at position 0] : String |
+| LambdaFlow.cs:183:16:183:17 | access to local variable id : (...) => ... [delegate return] : String | semmle.label | access to local variable id : (...) => ... [delegate return] : String |
+subpaths
+| LambdaFlow.cs:89:29:89:30 | [post] access to local variable id : Func<String,String> [delegate argument at position 0] : String | LambdaFlow.cs:87:39:87:39 | x : String | LambdaFlow.cs:87:44:87:44 | access to parameter x : String | LambdaFlow.cs:87:39:87:44 | (...) => ... : (...) => ... [delegate return] : String |
+| LambdaFlow.cs:89:29:89:30 | access to local variable id : (...) => ... [delegate return] : String | LambdaFlow.cs:80:40:80:45 | lambda : (...) => ... [delegate return] : String | LambdaFlow.cs:82:20:82:32 | delegate call : String | LambdaFlow.cs:89:26:89:39 | call to method M1 : String |
+| LambdaFlow.cs:89:33:89:38 | access to local variable source : String | LambdaFlow.cs:80:55:80:59 | input : String | LambdaFlow.cs:80:40:80:45 | lambda [Return] : Func<String,String> [delegate argument at position 0] : String | LambdaFlow.cs:89:29:89:30 | [post] access to local variable id : Func<String,String> [delegate argument at position 0] : String |
+| LambdaFlow.cs:182:16:182:17 | [post] access to local variable id : Func<String,String> [delegate argument at position 0] : String | LambdaFlow.cs:181:39:181:39 | x : String | LambdaFlow.cs:181:44:181:44 | access to parameter x : String | LambdaFlow.cs:181:39:181:44 | (...) => ... : (...) => ... [delegate return] : String |
+testFailures
+| LambdaFlow.cs:144:34:144:52 | // ... | Missing result: hasValueFlow=6 |
+| LambdaFlow.cs:176:18:176:23 | access to local variable output | Unexpected result: hasValueFlow=7 |
+#select
+| LambdaFlow.cs:12:18:12:18 | access to parameter s | LambdaFlow.cs:17:26:17:34 | call to method Source : String | LambdaFlow.cs:12:18:12:18 | access to parameter s | $@ | LambdaFlow.cs:17:26:17:34 | call to method Source : String | call to method Source : String |
+| LambdaFlow.cs:41:47:41:47 | access to parameter x | LambdaFlow.cs:35:26:35:34 | call to method Source : String | LambdaFlow.cs:41:47:41:47 | access to parameter x | $@ | LambdaFlow.cs:35:26:35:34 | call to method Source : String | call to method Source : String |
+| LambdaFlow.cs:65:18:65:25 | delegate call | LambdaFlow.cs:59:26:59:34 | call to method Source : String | LambdaFlow.cs:65:18:65:25 | delegate call | $@ | LambdaFlow.cs:59:26:59:34 | call to method Source : String | call to method Source : String |
+| LambdaFlow.cs:90:18:90:23 | access to local variable output | LambdaFlow.cs:88:26:88:34 | call to method Source : String | LambdaFlow.cs:90:18:90:23 | access to local variable output | $@ | LambdaFlow.cs:88:26:88:34 | call to method Source : String | call to method Source : String |
+| LambdaFlow.cs:176:18:176:23 | access to local variable output | LambdaFlow.cs:168:26:168:34 | call to method Source : String | LambdaFlow.cs:176:18:176:23 | access to local variable output | $@ | LambdaFlow.cs:168:26:168:34 | call to method Source : String | call to method Source : String |

csharp/ql/test/library-tests/dataflow/lambda/LambdaFlow.ql

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