package list

import (
	"github.com/stretchr/testify/assert"
	"testing"
)

func TestReadConj(t *testing.T) {
	l := New().Conj(5).Conj(6).Conj(7)
	assert.Equal(t, "(7 6 5)", l.String(), "should insert at head")
	l = Conj(New(), 4)
	assert.Equal(t, "(4 5)", l.String(), "should insert at head")
}

func TestReadFirst(t *testing.T) {
	l := New().Conj(5).Conj(6).Conj(7)
	assert.Equal(t, 7, l.First(), "should return first element")
	assert.Equal(t, nil, New().First(), "should return nil")
}

func TestReadRest(t *testing.T) {
	l := New().Conj(5).Conj(6).Conj(7)
	assert.Equal(t, "(6 5)", l.Rest().String(), "should return rest sublist")
	assert.Equal(t, "(5)", l.Rest().Rest().String(), "should return rest sublist")
	assert.Equal(t, "()", l.Rest().Rest().Rest().String(), "should return rest sublist")
	var nilPtr *List = nil
	assert.Equal(t, nilPtr, New().Rest(), "should return rest sublist")
	assert.Equal(t, nilPtr, Rest(New().Rest()), "should return rest sublist")
}