Skip leading step comments.

Author: AlphaOne1

file_migration.go

@@ -11,6 +11,7 @@ import (
 	"io/fs"
 	"log/slog"
 	"os"
+	"strings"
 )
 
 // FileMigration implements the Migration interface. It helps to apply migrations from a file or fs.FS.
@@ -102,16 +103,27 @@ func migrationFromFileFS(name string, dir fs.FS, log *slog.Logger) FileMigration
 }
 
 // applyStepsStream executes database migration steps read from an io.Reader, separated by semicolons, in a transaction.
-// Returns the corresponding error if any step execution fails.
+// Returns the corresponding error if any step execution fails. Also, as some database drivers or engines seem to not
+// support comments, leading comments are removed. This function does not undertake efforts to scan the SQL to find
+// other comments. So leading comments telling what a step is going to do, work. But comments in the middle of a
+// statement will not be removed. At least with SQLite this will lead to hard to find errors.
 func applyStepsStream(tx *sql.Tx, r io.Reader, id string, log *slog.Logger) error {
 	buf := bytes.Buffer{}
 
 	scanner := bufio.NewScanner(r)
+	newStep := true
 	var i int
 
 	for i = 0; scanner.Scan(); {
 		buf.Write(scanner.Bytes())
 
+		if newStep && strings.HasPrefix(scanner.Text(), "--") {
+			// skip leading comments
+			continue
+		}
+
+		newStep = false
+
 		if scanner.Text() == ";" {
 			log.Info("migration step",
 				slog.String("id", id),