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: link_eth_price_provider_test.go
    path of file: ./repos/chainlink/core/services/ocr2/plugins/ocr2vrf/juelsfeecoin
    
    the code of the file until where you have to start completion: package juelsfeecoin

import (
	"errors"
	"math/big"
	"testing"
	"time"

	"github.com/ethereum/go-ethereum/common"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/mock"
	"github.com/stretchr/testify/require"

	evmclimocks "github.com/smartcontractkit/chainlink/v2/core/chains/evm/client/mocks"
	"github.com/smartcontractkit/chainlink/v2/core/gethwrappers/generated/aggregator_v3_interface"
	"github.com/smartcontractkit/chainlink/v2/core/logger"
	"github.com/smartcontractkit/chainlink/v2/core/services/vrf/mocks"
)

func Test_JuelsPerFeeCoin(t *testing.T) {
	t.Parallel()

	t.Run("returns juels per fee coin", func(t *testing.T) {
		mockAggregator := mocks.NewAggregatorV3Interface(t)
		latestRoundData := aggregator_v3_interface.LatestRoundData{Answer: big.NewInt(10000)}
		mockAggregator.On("LatestRoundData", mock.Anything).Return(latestRoundData, nil)

		// Start linkEthPriceProvider.
		provider := &linkEthPriceProvider{
			aggregator:             mockAggregator,
			timeout:     
    
func Test_JuelsPerFeeCoin(t *testing.T) {
	t.Parallel()

	t.Run("returns juels per fee coin", func(t *testing.T) {
		mockAggregator := mocks.NewAggregatorV3Interface(t)
		latestRoundData := aggregator_v3_interface.LatestRoundData{Answer: big.NewInt(10000)}
		mockAggregator.On("LatestRoundData", mock.Anything).Return(latestRoundData, nil)

		// Start linkEthPriceProvider.
		provider := &linkEthPriceProvider{
			aggregator:             mockAggregator,
			timeout:                time.Second / 2,
			interval:               time.Second,
			stop:                   make(chan struct{}),
			currentJuelsPerFeeCoin: big.NewInt(0),
			lggr:                   logger.TestLogger(t),
		}
		go provider.run()
		t.Cleanup(func() { close(provider.stop) })

		// Assert correct initial price.
		price, err := provider.JuelsPerFeeCoin()
		require.NoError(t, err)
		assert.Equal(t, int64(0), price.Int64())

		// Wait until the price is updated.
		time.Sleep(2 * time.Second)

		// Ensure the correct price is returned.
		price, err = provider.JuelsPerFeeCoin()
		require.NoError(t, err)
		assert.Equal(t, int64(10000), price.Int64())
	})

	t.Run("returns juels per fee coin (error updating)", func(t *testing.T) {
		mockAggregator := mocks.NewAggregatorV3Interface(t)
		mockAggregator.On("LatestRoundData", mock.Anything).Return(aggregator_v3_interface.LatestRoundData{},
			errors.New("could not fetch"))

		// Start linkEthPriceProvider.
		provider := &linkEthPriceProvider{
			aggregator:             mockAggregator,
			timeout:                time.Second / 2,
			interval:               time.Second,
			stop:                   make(chan struct{}),
			currentJuelsPerFeeCoin: big.NewInt(0),
			lggr:                   logger.TestLogger(t),
		}
		go provider.run()
		t.Cleanup(func() { close(provider.stop) })

		// Assert correct initial price.
		price, err := provider.JuelsPerFeeCoin()
		require.NoError(t, err)
		assert.Equal(t, int64(0), price.Int64())

		// Wait until the price is updated.
		time.Sleep(2 * time.Second)

		// Ensure the correct price is returned.
		price, err = provider.JuelsPerFeeCoin()
		require.NoError(t, err)
		assert.Equal(t, int64(0), price.Int64())
	})

	t.Run("errors out for timeout >= interval", func(t *testing.T) {
		evmClient := evmclimocks.NewClient(t)
		_, err := NewLinkEthPriceProvider(common.Address{}, evmClient, time.Second, time.Second, logger.TestLogger(t))
		require.Error(t, err)
		require.Equal(t, "timeout must be less than interval", err.Error())
	})
}