From ed9cfac4968f2a58af34d3c4aa358004f62f5f93 Mon Sep 17 00:00:00 2001
From: Nikola Kovacs <nikola.kovacs@gmail.com>
Date: Sat, 21 May 2016 19:12:02 +0200
Subject: [PATCH] add failing test for long foreign keys in mysql

---
 association_test.go | 21 ++++++++++++++++++++-
 migration_test.go   |  8 +++++++-
 2 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/association_test.go b/association_test.go
index 52d2303f..e4aabb43 100644
--- a/association_test.go
+++ b/association_test.go
@@ -809,7 +809,7 @@ func TestRelated(t *testing.T) {
 
 func TestForeignKey(t *testing.T) {
 	for _, structField := range DB.NewScope(&User{}).GetStructFields() {
-		for _, foreignKey := range []string{"BillingAddressID", "ShippingAddressId", "CompanyID"} {
+		for _, foreignKey := range []string{"BillingAddressID", "ShippingAddressId", "CompanyID", "ReallyLongThingID"} {
 			if structField.Name == foreignKey && !structField.IsForeignKey {
 				t.Errorf(fmt.Sprintf("%v should be foreign key", foreignKey))
 			}
@@ -840,3 +840,22 @@ func TestForeignKey(t *testing.T) {
 		}
 	}
 }
+
+func TestLongForeignKey(t *testing.T) {
+	targetScope := DB.NewScope(&ReallyLongTableNameToTestMySQLNameLengthLimit{})
+	targetTableName := targetScope.TableName()
+	modelScope := DB.NewScope(&User{})
+	modelField, ok := modelScope.FieldByName("ReallyLongThingID")
+	if !ok {
+		t.Fatalf("Failed to get field by name: ReallyLongThingID")
+	}
+	targetField, ok := targetScope.FieldByName("ID")
+	if !ok {
+		t.Fatalf("Failed to get field by name: ID")
+	}
+	dest := fmt.Sprintf("%v(%v)", targetTableName, targetField.DBName)
+	err := DB.Model(&User{}).AddForeignKey(modelField.DBName, dest, "CASCADE", "CASCADE").Error
+	if err != nil {
+		t.Fatalf(fmt.Sprintf("Failed to create foreign key: %v", err))
+	}
+}
diff --git a/migration_test.go b/migration_test.go
index 38e5c1c2..fc692bcc 100644
--- a/migration_test.go
+++ b/migration_test.go
@@ -37,6 +37,12 @@ type User struct {
 	IgnoreStringSlice []string              `sql:"-"`
 	Ignored           struct{ Name string } `sql:"-"`
 	IgnoredPointer    *User                 `sql:"-"`
+	ReallyLongThingID int64
+	ReallyLongThing   ReallyLongTableNameToTestMySQLNameLengthLimit
+}
+
+type ReallyLongTableNameToTestMySQLNameLengthLimit struct {
+	Id int64
 }
 
 type CreditCard struct {
@@ -231,7 +237,7 @@ func runMigration() {
 		DB.Exec(fmt.Sprintf("drop table %v;", table))
 	}
 
-	values := []interface{}{&Product{}, &Email{}, &Address{}, &CreditCard{}, &Company{}, &Role{}, &Language{}, &HNPost{}, &EngadgetPost{}, &Animal{}, &User{}, &JoinTable{}, &Post{}, &Category{}, &Comment{}, &Cat{}, &Dog{}, &Toy{}}
+	values := []interface{}{&ReallyLongTableNameToTestMySQLNameLengthLimit{}, &Product{}, &Email{}, &Address{}, &CreditCard{}, &Company{}, &Role{}, &Language{}, &HNPost{}, &EngadgetPost{}, &Animal{}, &User{}, &JoinTable{}, &Post{}, &Category{}, &Comment{}, &Cat{}, &Dog{}, &Toy{}}
 	for _, value := range values {
 		DB.DropTable(value)
 	}