db: remove kvdb to sql migration from dev db stream

Remove the KVDB-to-SQL migration from the dev SQL migration set now
that this migration is now part of the production migration set.

As the migrations_dev folder no longer contains any migrations, we also
update the db logic and the gen_sqlc_docker.sh script to not error when
the folder(s) are empty.

db/migrations.go

@@ -1,6 +1,8 @@
 package db
 
 import (
+	"io/fs"
+
 	"github.com/golang-migrate/migrate/v4"
 	"github.com/golang-migrate/migrate/v4/database/pgx/v5"
 	"github.com/lightningnetwork/lnd/sqldb/v2"
@@ -28,9 +30,21 @@ const (
 	//
 	// NOTE: This MUST be updated when a migration is added or removed, from
 	// the migrations_dev directory.
-	LatestDevMigrationVersion = 1
+	LatestDevMigrationVersion = 0
 )
 
+// HasDevMigrations reports whether any dev SQL migration files are embedded in
+// the current build. This lets dev builds omit the separate dev migration set
+// cleanly when the directory exists but currently contains no migration files.
+func HasDevMigrations() bool {
+	files, err := fs.Glob(SqlSchemas, "sqlc/migrations_dev/*.*.sql")
+	if err != nil {
+		return false
+	}
+
+	return len(files) > 0
+}
+
 // MakeTestMigrationSets creates the migration sets for the unit test
 // environment.
 //
@@ -57,6 +71,12 @@ func MakeTestMigrationSets() []sqldb.MigrationSet {
 		},
 	}
 
+	// If there are no dev migrations in the sqlc/migrations_dev folder, we
+	// can return early.
+	if !HasDevMigrations() {
+		return []sqldb.MigrationSet{migSet}
+	}
+
 	migSetDev := sqldb.MigrationSet{
 		TrackingTableName: pgx.DefaultMigrationsTable + "_dev",
 		SQLFileDirectory:  "sqlc/migrations_dev",

db/migsets/sql_migrations_dev.go

@@ -13,12 +13,6 @@ import (
 	"github.com/lightningnetwork/lnd/sqldb/v2"
 )
 
-const (
-	// DevKVDBtoSQLMigVersion is the dev version of the migration that
-	// migrates the kvdb to the sql database.
-	DevKVDBtoSQLMigVersion = 1
-)
-
 // MakeMigrationSets creates the migration sets for the dev environments.
 func MakeMigrationSets(ctx context.Context,
 	basicClient lnrpc.LightningClient, macPath string,
@@ -56,6 +50,12 @@ func MakeMigrationSets(ctx context.Context,
 		},
 	}
 
+	// If there are no dev migrations in the sqlc/migrations_dev folder, we
+	// can return early.
+	if !db.HasDevMigrations() {
+		return []sqldb.MigrationSet{migSet}
+	}
+
 	// Create the dev migration set.
 	migSetDev := sqldb.MigrationSet{
 		TrackingTableName: pgx.DefaultMigrationsTable + "_dev",
@@ -69,22 +69,10 @@ func MakeMigrationSets(ctx context.Context,
 		// NOTE: This MUST be updated when a new dev migration is added.
 		LatestMigrationVersion: db.LatestDevMigrationVersion,
 
-		MakeProgrammaticMigrations: func(baseDB *sqldb.BaseDB) (
+		MakeProgrammaticMigrations: func(_ *sqldb.BaseDB) (
 			map[uint]migrate.ProgrammaticMigrEntry, error) {
 
-			// Any programmatic migrations added to this map will be
-			// executed when the dev migration number for the uint
-			// key is applied. If no entry exists for a
-			// given uint, then no programmatic migration will be
-			// executed for that migration number.
-			res := make(map[uint]migrate.ProgrammaticMigrEntry)
-
-			res[DevKVDBtoSQLMigVersion] = Mig6ProgrammaticMigration(
-				ctx, basicClient, baseDB, macPath, clock,
-				DevKVDBtoSQLMigVersion,
-			)
-
-			return res, nil
+			return make(map[uint]migrate.ProgrammaticMigrEntry), nil
 		},
 	}
 

db/sqlc/migrations_dev/000001_code_migration_kvdb_to_sql.down.sql

@@ -1 +0,0 @@
--- Comment to ensure the file created and picked up in the migration stream.

db/sqlc/migrations_dev/000001_code_migration_kvdb_to_sql.up.sql

@@ -1 +0,0 @@
--- Comment to ensure the file created and picked up in the migration stream.

scripts/gen_sqlc_docker.sh

@@ -1,6 +1,7 @@
 #!/bin/bash
 
 set -e
+shopt -s nullglob
 
 # restore_files is a function to restore original schema files.
 restore_files() {