From 45e804dd3fa3ca11fc3db0945fc3c4b93e8b7e66 Mon Sep 17 00:00:00 2001
From: Jinzhu <wosmvp@gmail.com>
Date: Mon, 29 Nov 2021 16:19:06 +0800
Subject: [PATCH] Fix call valuer interface when using nil value

---
 clause/expression.go | 2 +-
 statement.go         | 7 ++++++-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/clause/expression.go b/clause/expression.go
index d0498306..dde00b1d 100644
--- a/clause/expression.go
+++ b/clause/expression.go
@@ -368,7 +368,7 @@ func (like Like) NegationBuild(builder Builder) {
 }
 
 func eqNil(value interface{}) bool {
-	if valuer, ok := value.(driver.Valuer); ok {
+	if valuer, ok := value.(driver.Valuer); ok && !eqNilReflect(valuer) {
 		value, _ = valuer.Value()
 	}
 
diff --git a/statement.go b/statement.go
index 453e485e..5a948d3f 100644
--- a/statement.go
+++ b/statement.go
@@ -173,7 +173,12 @@ func (stmt *Statement) AddVar(writer clause.Writer, vars ...interface{}) {
 		case clause.Column, clause.Table:
 			stmt.QuoteTo(writer, v)
 		case Valuer:
-			stmt.AddVar(writer, v.GormValue(stmt.Context, stmt.DB))
+			reflectValue := reflect.ValueOf(v)
+			if reflectValue.Kind() == reflect.Ptr && reflectValue.IsNil() {
+				stmt.AddVar(writer, nil)
+			} else {
+				stmt.AddVar(writer, v.GormValue(stmt.Context, stmt.DB))
+			}
 		case clause.Expr:
 			v.Build(stmt)
 		case *clause.Expr: