fix: test race + gomodtidy

integration-tests/go.mod

@@ -5,7 +5,6 @@ go 1.21.7
 replace github.com/smartcontractkit/chainlink-solana => ../
 
 require (
-	github.com/ethereum/go-ethereum v1.13.8
 	github.com/gagliardetto/binary v0.7.7
 	github.com/gagliardetto/solana-go v1.8.4
 	github.com/google/uuid v1.6.0
@@ -136,6 +135,7 @@ require (
 	github.com/emicklei/go-restful/v3 v3.10.2 // indirect
 	github.com/esote/minmaxheap v1.0.0 // indirect
 	github.com/ethereum/c-kzg-4844 v0.4.0 // indirect
+	github.com/ethereum/go-ethereum v1.13.8 // indirect
 	github.com/evanphx/json-patch v5.6.0+incompatible // indirect
 	github.com/evanphx/json-patch/v5 v5.6.0 // indirect
 	github.com/exponent-io/jsonpath v0.0.0-20210407135951-1de76d718b3f // indirect

pkg/solana/cache_test.go

@@ -10,6 +10,7 @@ import (
 	"math/big"
 	"net/http"
 	"net/http/httptest"
+	"sync"
 	"testing"
 	"time"
 
@@ -150,7 +151,13 @@ func TestGetLatestTransmission(t *testing.T) {
 
 func TestCache(t *testing.T) {
 	ctx := tests.Context(t)
+
+	var lock sync.RWMutex // prevent race between cache + server shutdown
 	mockServer := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// use RLock to allow parallel server calls
+		lock.RLock()
+		defer lock.RUnlock()
+
 		// create response
 		body, err := io.ReadAll(r.Body)
 		require.NoError(t, err)
@@ -196,7 +203,11 @@ func TestCache(t *testing.T) {
 	assert.NoError(t, err)
 	assert.Equal(t, expectedTime, answer.Timestamp)
 	assert.Equal(t, expectedAns, answer.Data.String())
+
+	// use write lock to shutdown server to prevent read/write race
+	lock.Lock()
 	mockServer.Close()
+	lock.Unlock()
 }
 
 func TestNilPointerHandling(t *testing.T) {