tsid_test.go

/*
Copyright (c) 2023 Vishal Bihani

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package tsid

import (
	"math"
	"math/rand"
	"testing"
	"time"

	"github.com/stretchr/testify/assert"
)

const (
	LOOP_MAX = 1000
)

func Test_GetUnixMillis(t *testing.T) {

	t.Run("should return correct time", func(t *testing.T) {
		start := time.Now().UnixMilli()

		tsidFactory, _ := TsidFactoryBuilder().
			NewInstance()
		assert.NotNil(t, tsidFactory)

		tsid, _ := tsidFactory.Generate()
		assert.NotNil(t, tsid)

		middle := tsid.GetUnixMillis()
		end := time.Now().UnixMilli()

		if middle < start || (middle > end) {
			t.Fail()
		}
	})

	t.Run("given custom time should return correct time", func(t *testing.T) {
		bound := math.Pow(2, 42)

		for i := 0; i < LOOP_MAX; i++ {

			// generate random value
			random := rand.New(rand.NewSource(time.Now().UnixNano())).
				Int63n(int64(bound))

			// ensuring date is generated after TSID_EPOCH
			millis := random + TSID_EPOCH
			time := time.UnixMilli(millis)

			// int random supplier func
			intRandomSupplierFunc := func() (int32, error) {
				return 0, nil
			}

			intRandom := NewIntRandomWithSupplierFunc(intRandomSupplierFunc)

			tsidFactory, _ := TsidFactoryBuilder().
				WithClock(time).
				WithRandom(intRandom).
				NewInstance()
			assert.NotNil(t, tsidFactory)

			tsid, _ := tsidFactory.Generate()
			assert.NotNil(t, tsid)

			result := tsid.GetUnixMillis()
			assert.Equal(t, millis, result)
		}
	})

	t.Run("given custom epoch should return correct time", func(t *testing.T) {

		epoch := time.Date(1984, time.January, 1, 0, 0, 0, 0, time.UTC).
			UnixMilli()

		start := time.Now().UnixMilli()

		tsidFactory, _ := TsidFactoryBuilder().
			WithCustomEpoch(epoch).
			NewInstance()
		assert.NotNil(t, tsidFactory)

		tsid, _ := tsidFactory.Generate()
		assert.NotNil(t, tsid)

		middle := tsid.GetUnixMillisWithCustomEpoch(epoch)
		end := time.Now().UnixMilli()

		if middle < start || (middle > end) {
			t.Fail()
		}
	})
}