func TestStringSliceFilter(t *testing.T) { l := util.StringSlice{"All", "Go", "Code", "is"} rl := l.Filter(func(s string) bool { return s == "Go" }).ToString() assert.EqualValues(t, []string{"Go"}, rl) assert.Len(t, l, 4) l.Append("incredible", "easy", ",", "sometimes") assert.Len(t, l, 8) assert.EqualValues(t, []string{"Go"}, rl) }