invoices: parametrize invoice(registry) tests with InvoiceDB constructor

This commit extracts the InvoiceDB construction from all invoice and
registry tests such that we can later on run subtests with multiple
backends without needing to use tags.

invoices/test_utils_test.go

@@ -16,7 +16,6 @@ import (
 	"github.com/btcsuite/btcd/chaincfg"
 	"github.com/btcsuite/btcd/chaincfg/chainhash"
 	"github.com/lightningnetwork/lnd/chainntnfs"
-	"github.com/lightningnetwork/lnd/channeldb"
 	"github.com/lightningnetwork/lnd/clock"
 	invpkg "github.com/lightningnetwork/lnd/invoices"
 	"github.com/lightningnetwork/lnd/lntypes"
@@ -131,26 +130,8 @@ var (
 	testInvoiceCreationDate = testTime
 )
 
-func newTestChannelDB(t *testing.T, clock clock.Clock) (*channeldb.DB, error) {
-	t.Helper()
-
-	// Create channeldb for the first time.
-	cdb, err := channeldb.Open(
-		t.TempDir(), channeldb.OptionClock(clock),
-	)
-	if err != nil {
-		return nil, err
-	}
-
-	t.Cleanup(func() {
-		cdb.Close()
-	})
-
-	return cdb, nil
-}
-
 type testContext struct {
-	idb      *channeldb.DB
+	idb      invpkg.InvoiceDB
 	registry *invpkg.InvoiceRegistry
 	notifier *mockChainNotifier
 	clock    *clock.TestClock
@@ -166,17 +147,13 @@ func defaultRegistryConfig() invpkg.RegistryConfig {
 }
 
 func newTestContext(t *testing.T,
-	registryCfg *invpkg.RegistryConfig) *testContext {
+	registryCfg *invpkg.RegistryConfig,
+	makeDB func(t *testing.T) (invpkg.InvoiceDB,
+		*clock.TestClock)) *testContext {
 
 	t.Helper()
 
-	clock := clock.NewTestClock(testTime)
-
-	idb, err := newTestChannelDB(t, clock)
-	if err != nil {
-		t.Fatal(err)
-	}
-
+	idb, clock := makeDB(t)
 	notifier := newMockNotifier()
 
 	expiryWatcher := invpkg.NewInvoiceExpiryWatcher(
@@ -192,10 +169,7 @@ func newTestContext(t *testing.T,
 	// Instantiate and start the invoice ctx.registry.
 	registry := invpkg.NewRegistry(idb, expiryWatcher, &cfg)
 
-	err = registry.Start()
-	if err != nil {
-		t.Fatal(err)
-	}
+	require.NoError(t, registry.Start())
 	t.Cleanup(func() {
 		require.NoError(t, registry.Stop())
 	})