add test case for len function

Signed-off-by: czechbol <[email protected]>

testutils/g115_samples.go

@@ -493,6 +493,23 @@ func foo(x int) uint32 {
         }
         return uint32(x)
 }
+`,
+	}, 0, gosec.NewConfig()},
+	{[]string{
+		`
+package main
+
+import (
+        "math"
+)
+
+func foo(items []string) uint32 {
+        x := len(items)
+        if x > math.MaxUint32 {
+            return math.MaxUint32
+        }
+        return uint32(x)
+}
 `,
 	}, 0, gosec.NewConfig()},
 }