From 778379538b2f46052eb7c0d02573b89a0fea0f83 Mon Sep 17 00:00:00 2001
From: SG Command <sgcommand@git.warky.dev>
Date: Sat, 3 Oct 2026 12:42:07 +0200
Subject: [PATCH] fix: make MySQL writer execute generated DDL

---
 pkg/writers/mysql/writer.go      | 27 +++++++++++++++++++++++----
 pkg/writers/mysql/writer_test.go |  7 +++++++
 2 files changed, 30 insertions(+), 4 deletions(-)

diff --git a/pkg/writers/mysql/writer.go b/pkg/writers/mysql/writer.go
index 131a464..dd8707b 100644
--- a/pkg/writers/mysql/writer.go
+++ b/pkg/writers/mysql/writer.go
@@ -9,6 +9,8 @@ import (
 	"sort"
 	"strings"
 
+	_ "github.com/go-sql-driver/mysql"
+
 	"git.warky.dev/wdevs/relspecgo/pkg/mariadb"
 	"git.warky.dev/wdevs/relspecgo/pkg/models"
 	"git.warky.dev/wdevs/relspecgo/pkg/writers"
@@ -39,7 +41,13 @@ func (w *Writer) WriteDatabase(db *models.Database) error {
 			w.writer = os.Stdout
 		}
 	}
-	fmt.Fprintf(w.writer, "-- MySQL Database Schema\n-- Database: %s\n-- Generated by RelSpec\n\n", db.Name)
+	return w.writeDatabaseDDL(db)
+}
+
+func (w *Writer) writeDatabaseDDL(db *models.Database) error {
+	if _, err := fmt.Fprintf(w.writer, "-- MySQL Database Schema\n-- Database: %s\n-- Generated by RelSpec\n\n", db.Name); err != nil {
+		return err
+	}
 	for _, s := range db.Schemas {
 		if err := w.WriteSchema(s); err != nil {
 			return err
@@ -121,7 +129,7 @@ func (w *Writer) execute(dbm *models.Database, conn string) error {
 	var b strings.Builder
 	old := w.writer
 	w.writer = &b
-	if err := w.WriteDatabase(dbm); err != nil {
+	if err := w.writeDatabaseDDL(dbm); err != nil {
 		w.writer = old
 		return err
 	}
@@ -132,8 +140,8 @@ func (w *Writer) execute(dbm *models.Database, conn string) error {
 	}
 	defer db.Close()
 	for _, stmt := range strings.Split(b.String(), ";\n") {
-		stmt = strings.TrimSpace(stmt)
-		if stmt == "" || strings.HasPrefix(stmt, "--") {
+		stmt = stripComments(strings.TrimSpace(stmt))
+		if stmt == "" {
 			continue
 		}
 		if _, err := db.ExecContext(context.Background(), stmt); err != nil {
@@ -142,6 +150,17 @@ func (w *Writer) execute(dbm *models.Database, conn string) error {
 	}
 	return nil
 }
+func stripComments(sqlText string) string {
+	lines := strings.Split(sqlText, "\n")
+	kept := lines[:0]
+	for _, line := range lines {
+		if !strings.HasPrefix(strings.TrimSpace(line), "--") {
+			kept = append(kept, line)
+		}
+	}
+	return strings.TrimSpace(strings.Join(kept, "\n"))
+}
+
 func quote(s string) string { return "`" + strings.ReplaceAll(s, "`", "``") + "`" }
 func quoted(xs []string) string {
 	out := make([]string, len(xs))
diff --git a/pkg/writers/mysql/writer_test.go b/pkg/writers/mysql/writer_test.go
index 48923fb..1a53fad 100644
--- a/pkg/writers/mysql/writer_test.go
+++ b/pkg/writers/mysql/writer_test.go
@@ -9,6 +9,13 @@ import (
 	"git.warky.dev/wdevs/relspecgo/pkg/writers"
 )
 
+func TestStripComments(t *testing.T) {
+	got := stripComments("-- header\nCREATE TABLE `users` (\n  `id` INT\n);")
+	if strings.HasPrefix(got, "--") || !strings.HasPrefix(got, "CREATE TABLE") {
+		t.Fatalf("stripComments() = %q", got)
+	}
+}
+
 func TestWriterGeneratesMySQLDDL(t *testing.T) {
 	db := models.InitDatabase("app")
 	s := models.InitSchema("app")