Added more tests

re_test.go

@@ -150,6 +150,9 @@ var reTests = []struct {
 	{"^((3[7-9])|([4-9][0-9])|([1-9][0-9][0-9])|(1000))$", "4000", []Group{}},
 
 	// Todo - add lookaround tests
+	{"(?<=bo)y", "boy", []Group{{2, 3}}},
+	{"bo(?=y)", "boy", []Group{{0, 2}}},
+
 	// Todo - add numeric range tests
 	// Todo - add capturing group tests
 	{"(?<=f)f+(?=f)", "fffff", []Group{{1, 4}}},