You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: migrate_test.go
    path of file: ./repos/mattermost/server/config
    
    the code of the file until where you have to start completion: // Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
// See LICENSE.txt for license information.

package config

import (
	"os"
	"path"
	"testing"

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

	"github.com/mattermost/mattermost/server/public/model"
)

type cleanUpFn func(store *Store)

func TestMigrate(t *testing.T) {
	if testing.Short() {
		t.Skip("skipping migration test in short mode")
	}
	files := []string{
		"IdpCertificateFile",
		"PublicCertificateFile",
		"PrivateKeyFile",
		"internal.crt",
		"internal2.crt",
	}
	filesData := make([]string, len(files))
	for i := range files {
		// Generate random data for each file, ensuring that stale data from a past test
		// won't generate a false positive.
		filesData[i] = model.NewId()
	}

	setup := func(t *testing.T) {
		os.Clearenv()
		t.Helper()

		tempDir, err := os.MkdirTemp("", "TestMigrate")
		require.NoError(t, err)
		t.Cleanup(func() {
			os.RemoveAll(tempDir)
		})

		err = os.Chdir(tempDir)
		require.NoError(t, err)

		truncateTables(t)
	}

	setupSource := func(t *testing.T, source *Store) cleanUpFn {
		t.Helper()

		cfg := source.Get()
		originalCfg := cfg.Clone()
		cfg.ServiceSettings.SiteURL = model.NewString("http://example.com")
		cfg.SamlSettings.IdpCertificateFile = &files[0]
		cfg.SamlSettings.PublicCertificateFile = &files[1]
		cfg.SamlSettings.PrivateKeyFile = &files[2]
		cfg.PluginSettings.SignaturePublicKeyFiles = []string{
			files[3],
			files[4],
		}
		cfg.SqlSettings.DataSourceReplicas = []string{
			"mysql://mmuser:password@tcp(replicahost:3306)/mattermost",
		}
		cfg.SqlSettings.DataSourceSearchReplicas = []string{
			"mysql://mmuser:password@tcp(searchreplicahost:3306)/mattermost",
		}

		_, _, err := source.Set(cfg)
		require.NoError(t, err)

		for i, file := range files {
			err = source.SetFile(file, []byte(filesData[i]))
			require.NoError(t, err)
		}

		return func(store *Store) {
			_, _, err := store.Set(originalCfg)
			require.NoError(t, err)
		}
	}

	assertDestination := func(t *testing.T, destination *Store, source *Store) {
		t.Helper()

		for i, file := range files {
			hasFile, err := destination.HasFile(file)
			require.NoError(t, err)
			require.Truef(t, hasFile, "destination missing file %s
    
func TestMigrate(t *testing.T) {
	if testing.Short() {
		t.Skip("skipping migration test in short mode")
	}
	files := []string{
		"IdpCertificateFile",
		"PublicCertificateFile",
		"PrivateKeyFile",
		"internal.crt",
		"internal2.crt",
	}
	filesData := make([]string, len(files))
	for i := range files {
		// Generate random data for each file, ensuring that stale data from a past test
		// won't generate a false positive.
		filesData[i] = model.NewId()
	}

	setup := func(t *testing.T) {
		os.Clearenv()
		t.Helper()

		tempDir, err := os.MkdirTemp("", "TestMigrate")
		require.NoError(t, err)
		t.Cleanup(func() {
			os.RemoveAll(tempDir)
		})

		err = os.Chdir(tempDir)
		require.NoError(t, err)

		truncateTables(t)
	}

	setupSource := func(t *testing.T, source *Store) cleanUpFn {
		t.Helper()

		cfg := source.Get()
		originalCfg := cfg.Clone()
		cfg.ServiceSettings.SiteURL = model.NewString("http://example.com")
		cfg.SamlSettings.IdpCertificateFile = &files[0]
		cfg.SamlSettings.PublicCertificateFile = &files[1]
		cfg.SamlSettings.PrivateKeyFile = &files[2]
		cfg.PluginSettings.SignaturePublicKeyFiles = []string{
			files[3],
			files[4],
		}
		cfg.SqlSettings.DataSourceReplicas = []string{
			"mysql://mmuser:password@tcp(replicahost:3306)/mattermost",
		}
		cfg.SqlSettings.DataSourceSearchReplicas = []string{
			"mysql://mmuser:password@tcp(searchreplicahost:3306)/mattermost",
		}

		_, _, err := source.Set(cfg)
		require.NoError(t, err)

		for i, file := range files {
			err = source.SetFile(file, []byte(filesData[i]))
			require.NoError(t, err)
		}

		return func(store *Store) {
			_, _, err := store.Set(originalCfg)
			require.NoError(t, err)
		}
	}

	assertDestination := func(t *testing.T, destination *Store, source *Store) {
		t.Helper()

		for i, file := range files {
			hasFile, err := destination.HasFile(file)
			require.NoError(t, err)
			require.Truef(t, hasFile, "destination missing file %s", file)

			actualData, err := destination.GetFile(file)
			require.NoError(t, err)
			assert.Equalf(t, []byte(filesData[i]), actualData, "destination has wrong contents for file %s", file)
		}

		assert.Equal(t, source.Get(), destination.Get())
	}

	t.Run("database to file", func(t *testing.T) {
		setup(t)

		pwd, err := os.Getwd()
		require.NoError(t, err)

		sqlSettings := mainHelper.GetSQLSettings()
		destinationDSN := path.Join(pwd, "config-custom.json")
		sourceDSN := getDsn(*sqlSettings.DriverName, *sqlSettings.DataSource)

		sourcedb, err := NewDatabaseStore(sourceDSN)
		require.NoError(t, err)
		source, err := NewStoreFromBacking(sourcedb, nil, false)
		require.NoError(t, err)
		defer source.Close()

		cleanUp := setupSource(t, source)
		err = Migrate(sourceDSN, destinationDSN)
		require.NoError(t, err)

		destinationfile, err := NewFileStore(destinationDSN, false)
		require.NoError(t, err)
		destination, err := NewStoreFromBacking(destinationfile, nil, false)
		require.NoError(t, err)
		defer destination.Close()
		defer cleanUp(destination)

		assertDestination(t, destination, source)
	})

	t.Run("file to database", func(t *testing.T) {
		setup(t)

		pwd, err := os.Getwd()
		require.NoError(t, err)

		sqlSettings := mainHelper.GetSQLSettings()
		sourceDSN := path.Join(pwd, "config-custom.json")
		destinationDSN := getDsn(*sqlSettings.DriverName, *sqlSettings.DataSource)

		sourcefile, err := NewFileStore(sourceDSN, true)
		require.NoError(t, err)
		source, err := NewStoreFromBacking(sourcefile, nil, false)
		require.NoError(t, err)
		defer source.Close()

		cleanUp := setupSource(t, source)
		err = Migrate(sourceDSN, destinationDSN)
		require.NoError(t, err)

		destinationdb, err := NewDatabaseStore(destinationDSN)
		require.NoError(t, err)
		destination, err := NewStoreFromBacking(destinationdb, nil, false)
		require.NoError(t, err)
		defer destination.Close()
		defer cleanUp(destination)

		assertDestination(t, destination, source)
	})
}