Rust: Add more CFG tests

rust/ql/test/library-tests/controlflow/test.rs

@@ -141,6 +141,22 @@ mod if_expression {
         0
     }
 
+    fn test_and_if_let(a: bool, b: Option<bool>, c: bool) -> bool {
+        if a && let Some(d) = b {
+            d
+        } else {
+            false
+        }
+    }
+
+    fn test_and_if_let2(a: bool, b: i64, c: bool) -> bool {
+        if a && let d = b && c{
+            d > 0
+        } else {
+            false
+        }
+    }
+
     fn test_nested_if(a: i64) -> i64 {
         if (if a < 0 { a < -10 } else { a > 10 }) {
             1
@@ -262,6 +278,10 @@ mod logical_operators {
             false
         }
     }
+
+    fn test_and_return(a : bool) {
+        a && return;
+    }
 }
 
 mod question_mark_operator {