From 38d1cd2bf182f55f28a8c909395ceaa2019d8b99 Mon Sep 17 00:00:00 2001
From: Jinzhu <wosmvp@gmail.com>
Date: Sat, 6 Jun 2020 21:35:28 +0800
Subject: [PATCH] Replace For with Locking

---
 clause/locking.go      | 41 ++++++++++++-----------------------------
 clause/locking_test.go | 18 +++++-------------
 2 files changed, 17 insertions(+), 42 deletions(-)

diff --git a/clause/locking.go b/clause/locking.go
index 3be1063b..290aac92 100644
--- a/clause/locking.go
+++ b/clause/locking.go
@@ -1,9 +1,5 @@
 package clause
 
-type For struct {
-	Lockings []Locking
-}
-
 type Locking struct {
 	Strength string
 	Table    Table
@@ -11,38 +7,25 @@ type Locking struct {
 }
 
 // Name where clause name
-func (f For) Name() string {
+func (locking Locking) Name() string {
 	return "FOR"
 }
 
 // Build build where clause
-func (f For) Build(builder Builder) {
-	for idx, locking := range f.Lockings {
-		if idx > 0 {
-			builder.WriteByte(' ')
-		}
+func (locking Locking) Build(builder Builder) {
+	builder.WriteString(locking.Strength)
+	if locking.Table.Name != "" {
+		builder.WriteString(" OF ")
+		builder.WriteQuoted(locking.Table)
+	}
 
-		builder.WriteString("FOR ")
-		builder.WriteString(locking.Strength)
-		if locking.Table.Name != "" {
-			builder.WriteString(" OF ")
-			builder.WriteQuoted(locking.Table)
-		}
-
-		if locking.Options != "" {
-			builder.WriteByte(' ')
-			builder.WriteString(locking.Options)
-		}
+	if locking.Options != "" {
+		builder.WriteByte(' ')
+		builder.WriteString(locking.Options)
 	}
 }
 
 // MergeClause merge order by clauses
-func (f For) MergeClause(clause *Clause) {
-	clause.Name = ""
-
-	if v, ok := clause.Expression.(For); ok {
-		f.Lockings = append(v.Lockings, f.Lockings...)
-	}
-
-	clause.Expression = f
+func (locking Locking) MergeClause(clause *Clause) {
+	clause.Expression = locking
 }
diff --git a/clause/locking_test.go b/clause/locking_test.go
index 6f507692..5ca30ef0 100644
--- a/clause/locking_test.go
+++ b/clause/locking_test.go
@@ -14,24 +14,16 @@ func TestFor(t *testing.T) {
 		Vars    []interface{}
 	}{
 		{
-			[]clause.Interface{clause.Select{}, clause.From{}, clause.For{
-				Lockings: []clause.Locking{{Strength: "UPDATE"}},
-			}},
+			[]clause.Interface{clause.Select{}, clause.From{}, clause.Locking{Strength: "UPDATE"}},
 			"SELECT * FROM `users` FOR UPDATE", nil,
 		},
 		{
-			[]clause.Interface{clause.Select{}, clause.From{}, clause.For{
-				Lockings: []clause.Locking{{Strength: "UPDATE"}, {Strength: "SHARE", Table: clause.Table{Name: clause.CurrentTable}}},
-			}},
-			"SELECT * FROM `users` FOR UPDATE FOR SHARE OF `users`", nil,
+			[]clause.Interface{clause.Select{}, clause.From{}, clause.Locking{Strength: "SHARE", Table: clause.Table{Name: clause.CurrentTable}}},
+			"SELECT * FROM `users` FOR SHARE OF `users`", nil,
 		},
 		{
-			[]clause.Interface{clause.Select{}, clause.From{}, clause.For{
-				Lockings: []clause.Locking{{Strength: "UPDATE"}, {Strength: "SHARE", Table: clause.Table{Name: clause.CurrentTable}}},
-			}, clause.For{
-				Lockings: []clause.Locking{{Strength: "UPDATE", Options: "NOWAIT"}},
-			}},
-			"SELECT * FROM `users` FOR UPDATE FOR SHARE OF `users` FOR UPDATE NOWAIT", nil,
+			[]clause.Interface{clause.Select{}, clause.From{}, clause.Locking{Strength: "UPDATE"}, clause.Locking{Strength: "UPDATE", Options: "NOWAIT"}},
+			"SELECT * FROM `users` FOR UPDATE NOWAIT", nil,
 		},
 	}