From a0b70669e7b148b58faf65de667a8ca8bf738e45 Mon Sep 17 00:00:00 2001
From: Ian Tan <ian.tan@techinasia.com>
Date: Wed, 22 Nov 2017 15:44:06 +0800
Subject: [PATCH] Support mock has one

---
 expecter_result.go | 20 ++++++++++++++++++++
 expecter_test.go   | 31 ++++++++++++++++++++++++++++---
 2 files changed, 48 insertions(+), 3 deletions(-)

diff --git a/expecter_result.go b/expecter_result.go
index 59c2379b..b983672d 100644
--- a/expecter_result.go
+++ b/expecter_result.go
@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"reflect"
 
+	"github.com/davecgh/go-spew/spew"
 	sqlmock "gopkg.in/DATA-DOG/go-sqlmock.v1"
 )
 
@@ -69,7 +70,25 @@ func getRelationRows(rVal reflect.Value, fieldName string, relation *Relationshi
 	)
 
 	switch relation.Kind {
+	case "has_one":
+		// just a plain struct
+		scope := &Scope{Value: rVal.Interface()}
+
+		for _, field := range scope.GetModelStruct().StructFields {
+			if field.IsNormal {
+				columns = append(columns, field.DBName)
+			}
+		}
+
+		rows = sqlmock.NewRows(columns)
+
+		// we don't have a slice
+		row := getRowForFields(scope.Fields())
+		rows = rows.AddRow(row...)
+
+		return rows, true
 	case "has_many", "many_to_many":
+		// in this case, we're guarnateed to have a slice
 		elem := rVal.Type().Elem()
 		scope := &Scope{Value: reflect.New(elem).Interface()}
 
@@ -165,6 +184,7 @@ func (q *SqlmockQuery) Returns(out interface{}) ExpectedQuery {
 
 	for i, query := range q.queries {
 		query.WillReturnRows(rows[i])
+		spew.Dump(query)
 	}
 
 	return q
diff --git a/expecter_test.go b/expecter_test.go
index 6b84f198..fbdbbb2d 100644
--- a/expecter_test.go
+++ b/expecter_test.go
@@ -145,6 +145,31 @@ func TestMockPreloadHasMany(t *testing.T) {
 	}
 }
 
+func TestMockPreloadHasOne(t *testing.T) {
+	db, expect, err := gorm.NewDefaultExpecter()
+	defer func() {
+		db.Close()
+	}()
+
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	in := User{Id: 1}
+	out := User{Id: 1, CreditCard: CreditCard{Number: "12345678"}}
+
+	expect.Preload("CreditCard").Find(&in).Returns(out)
+	db.Preload("CreditCard").Find(&in)
+
+	if err := expect.AssertExpectations(); err != nil {
+		t.Error(err)
+	}
+
+	if !reflect.DeepEqual(in, out) {
+		t.Error("In and out are not equal")
+	}
+}
+
 func TestMockPreloadMany2Many(t *testing.T) {
 	db, expect, err := gorm.NewDefaultExpecter()
 	defer func() {
@@ -166,7 +191,7 @@ func TestMockPreloadMany2Many(t *testing.T) {
 		t.Error(err)
 	}
 
-	// if !reflect.DeepEqual(in, out) {
-	// 	t.Error("In and out are not equal")
-	// }
+	// 	if !reflect.DeepEqual(in, out) {
+	// 		t.Error("In and out are not equal")
+	// 	}
 }