From dd0d74fad06342a792a1cdc20101a57ee019f447 Mon Sep 17 00:00:00 2001
From: Jinzhu <wosmvp@gmail.com>
Date: Thu, 3 Sep 2020 19:16:55 +0800
Subject: [PATCH] Fix transaction on closed conn when using prepared statement,
 close #3380

---
 prepare_stmt.go           | 14 ++++++++++++++
 tests/tests_test.go       |  4 ++--
 tests/transaction_test.go | 21 +++++++++++++++++++++
 3 files changed, 37 insertions(+), 2 deletions(-)

diff --git a/prepare_stmt.go b/prepare_stmt.go
index de7e2a26..14a6aaec 100644
--- a/prepare_stmt.go
+++ b/prepare_stmt.go
@@ -99,6 +99,20 @@ type PreparedStmtTX struct {
 	PreparedStmtDB *PreparedStmtDB
 }
 
+func (tx *PreparedStmtTX) Commit() error {
+	if tx.Tx != nil {
+		return tx.Tx.Commit()
+	}
+	return ErrInvalidTransaction
+}
+
+func (tx *PreparedStmtTX) Rollback() error {
+	if tx.Tx != nil {
+		return tx.Tx.Rollback()
+	}
+	return ErrInvalidTransaction
+}
+
 func (tx *PreparedStmtTX) ExecContext(ctx context.Context, query string, args ...interface{}) (result sql.Result, err error) {
 	stmt, err := tx.PreparedStmtDB.prepare(ctx, query)
 	if err == nil {
diff --git a/tests/tests_test.go b/tests/tests_test.go
index 192160a0..cb73d267 100644
--- a/tests/tests_test.go
+++ b/tests/tests_test.go
@@ -21,7 +21,7 @@ var DB *gorm.DB
 func init() {
 	var err error
 	if DB, err = OpenTestConnection(); err != nil {
-		log.Printf("failed to connect database, got error %v\n", err)
+		log.Printf("failed to connect database, got error %v", err)
 		os.Exit(1)
 	} else {
 		sqlDB, err := DB.DB()
@@ -30,7 +30,7 @@ func init() {
 		}
 
 		if err != nil {
-			log.Printf("failed to connect database, got error %v\n", err)
+			log.Printf("failed to connect database, got error %v", err)
 		}
 
 		RunMigrations()
diff --git a/tests/transaction_test.go b/tests/transaction_test.go
index aea151d9..334600b8 100644
--- a/tests/transaction_test.go
+++ b/tests/transaction_test.go
@@ -282,3 +282,24 @@ func TestNestedTransactionWithBlock(t *testing.T) {
 		t.Fatalf("Should find saved record")
 	}
 }
+
+func TestTransactionOnClosedConn(t *testing.T) {
+	DB, err := OpenTestConnection()
+	if err != nil {
+		t.Fatalf("failed to connect database, got error %v", err)
+	}
+	rawDB, _ := DB.DB()
+	rawDB.Close()
+
+	if err := DB.Transaction(func(tx *gorm.DB) error {
+		return nil
+	}); err == nil {
+		t.Errorf("should returns error when commit with closed conn, got error %v", err)
+	}
+
+	if err := DB.Session(&gorm.Session{PrepareStmt: true}).Transaction(func(tx *gorm.DB) error {
+		return nil
+	}); err == nil {
+		t.Errorf("should returns error when commit with closed conn, got error %v", err)
+	}
+}