diff --git a/test/3-copyFiles/source/app.d b/test/3-copyFiles/source/app.d
index dbab869..a39cc7b 100644
--- a/test/3-copyFiles/source/app.d
+++ b/test/3-copyFiles/source/app.d
@@ -1,6 +1,24 @@
-import std.stdio;
+import std.algorithm, std.array, std.file, std.path;
 
-void main()
+void main(string[] args)
 {
-    writeln(__FUNCTION__);
+	immutable root = args[0].dirName; // get the bin dir
+	immutable pfx = root.length + "/".length;
+	auto files = dirEntries(root, SpanMode.breadth).map!(n => n[pfx .. $]).array.sort().release;
+
+	assert(files ==
+		[
+			"copyfiles-test", "file_to_copy.txt", "file_to_copy_mask1.txt",
+			"file_to_copy_mask2.txt", "hdpi", "hdpi/file1.txt", "hdpi/file2.txt",
+			"hdpi/file3.txt", "hdpi/nested_dir", "hdpi/nested_dir/nested_file.txt",
+			"ldpi", "ldpi/file1.txt", "ldpi/file2.txt", "ldpi/file3.txt", "mdpi",
+			"mdpi/file1.txt", "mdpi/file2.txt", "mdpi/file3.txt", "res",
+			"res/.nocopy", "res/.nocopy/file_inside_dot_prefixed_dir.txt",
+			"res/hdpi", "res/hdpi/file1.txt", "res/hdpi/file2.txt", "res/hdpi/file3.txt",
+			"res/hdpi/nested_dir", "res/hdpi/nested_dir/nested_file.txt", "res/i18n",
+			"res/i18n/resource_en.txt", "res/i18n/resource_fr.txt", "res/ldpi",
+			"res/ldpi/file1.txt", "res/ldpi/file2.txt", "res/ldpi/file3.txt", "res/mdpi",
+			"res/mdpi/file1.txt", "res/mdpi/file2.txt", "res/mdpi/file3.txt"
+		], files.join(", ")
+	);
 }