channeldb: add shouldFail param to ApplyMigrationWithDB

Add a shouldFail boolean parameter to the migtest ApplyMigrationWithDB
in order to make it easier to test migration failures.

channeldb/migration30/migration_test.go

@@ -108,6 +108,7 @@ func TestMigrateRevocationLog(t *testing.T) {
 				beforeMigration,
 				afterMigration,
 				MigrateRevocationLog,
+				false,
 			)
 		})
 		if !success {
@@ -569,5 +570,6 @@ func BenchmarkMigration(b *testing.B) {
 
 			return MigrateRevocationLog(db)
 		},
+		false,
 	)
 }

channeldb/migtest/migtest.go

@@ -90,7 +90,7 @@ func ApplyMigration(t *testing.T,
 // supplied migration functions to take a db instance and construct their own
 // database transactions.
 func ApplyMigrationWithDb(t testing.TB, beforeMigration, afterMigration,
-	migrationFunc func(db kvdb.Backend) error) {
+	migrationFunc func(db kvdb.Backend) error, shouldFail bool) {
 
 	t.Helper()
 
@@ -106,8 +106,11 @@ func ApplyMigrationWithDb(t testing.TB, beforeMigration, afterMigration,
 	}
 
 	// Apply migration.
-	if err := migrationFunc(cdb); err != nil {
+	err = migrationFunc(cdb)
-		t.Fatalf("migrationFunc error: %v", err)
+	if shouldFail {
+		require.Error(t, err)
+	} else {
+		require.NoError(t, err)
 	}
 
 	// If there's no afterMigration, exit here.