From 12ba285a52fb25c3422e16226666ba791f376c0b Mon Sep 17 00:00:00 2001
From: Mathias Zeller <62462901+matoubidou@users.noreply.github.com>
Date: Tue, 10 Oct 2023 08:46:32 +0200
Subject: [PATCH] *datatypes.JSON in model causes panic on tx.Statement.Changed
 (#6611)

* do not panic on nil

* more explanation in comments

* get things compact
---
 utils/utils.go      | 33 +++++++++++++++++++++------------
 utils/utils_test.go |  1 +
 2 files changed, 22 insertions(+), 12 deletions(-)

diff --git a/utils/utils.go b/utils/utils.go
index ddbca60a..c8fec5b0 100644
--- a/utils/utils.go
+++ b/utils/utils.go
@@ -89,19 +89,28 @@ func Contains(elems []string, elem string) bool {
 	return false
 }
 
-func AssertEqual(src, dst interface{}) bool {
-	if !reflect.DeepEqual(src, dst) {
-		if valuer, ok := src.(driver.Valuer); ok {
-			src, _ = valuer.Value()
-		}
-
-		if valuer, ok := dst.(driver.Valuer); ok {
-			dst, _ = valuer.Value()
-		}
-
-		return reflect.DeepEqual(src, dst)
+func AssertEqual(x, y interface{}) bool {
+	if reflect.DeepEqual(x, y) {
+		return true
 	}
-	return true
+	if x == nil || y == nil {
+		return false
+	}
+
+	xval := reflect.ValueOf(x)
+	yval := reflect.ValueOf(y)
+	if xval.Kind() == reflect.Ptr && xval.IsNil() ||
+		yval.Kind() == reflect.Ptr && yval.IsNil() {
+		return false
+	}
+
+	if valuer, ok := x.(driver.Valuer); ok {
+		x, _ = valuer.Value()
+	}
+	if valuer, ok := y.(driver.Valuer); ok {
+		y, _ = valuer.Value()
+	}
+	return reflect.DeepEqual(x, y)
 }
 
 func ToString(value interface{}) string {
diff --git a/utils/utils_test.go b/utils/utils_test.go
index 71eef964..d0486822 100644
--- a/utils/utils_test.go
+++ b/utils/utils_test.go
@@ -98,6 +98,7 @@ func TestAssertEqual(t *testing.T) {
 		{"error not equal", errors.New("1"), errors.New("2"), false},
 		{"driver.Valuer equal", ModifyAt{Time: now, Valid: true}, ModifyAt{Time: now, Valid: true}, true},
 		{"driver.Valuer not equal", ModifyAt{Time: now, Valid: true}, ModifyAt{Time: now.Add(time.Second), Valid: true}, false},
+		{"driver.Valuer equal (ptr to nil ptr)", (*ModifyAt)(nil), &ModifyAt{}, false},
 	}
 	for _, test := range assertEqualTests {
 		t.Run(test.name, func(t *testing.T) {