upgrade to use testfixtures v3 (#11904)

* upgrade to use testfixtures v3

* simplify logic

* make vendor

* update per @lunny

* Update templates/repo/empty.tmpl

* Update templates/repo/empty.tmpl

Co-authored-by: Lauris BH <lauris@nix.lv>

vendor/github.com/go-testfixtures/testfixtures/v3/helper.go

@@ -0,0 +1,71 @@
+package testfixtures
+
+import (
+	"database/sql"
+	"fmt"
+)
+
+const (
+	paramTypeDollar = iota + 1
+	paramTypeQuestion
+	paramTypeAtSign
+)
+
+type loadFunction func(tx *sql.Tx) error
+
+type helper interface {
+	init(*sql.DB) error
+	disableReferentialIntegrity(*sql.DB, loadFunction) error
+	paramType() int
+	databaseName(queryable) (string, error)
+	tableNames(queryable) ([]string, error)
+	isTableModified(queryable, string) (bool, error)
+	afterLoad(queryable) error
+	quoteKeyword(string) string
+	whileInsertOnTable(*sql.Tx, string, func() error) error
+}
+
+type queryable interface {
+	Exec(string, ...interface{}) (sql.Result, error)
+	Query(string, ...interface{}) (*sql.Rows, error)
+	QueryRow(string, ...interface{}) *sql.Row
+}
+
+// batchSplitter is an interface with method which returns byte slice for
+// splitting SQL batches. This need to split sql statements and run its
+// separately.
+//
+// For Microsoft SQL Server batch splitter is "GO". For details see
+// https://docs.microsoft.com/en-us/sql/t-sql/language-elements/sql-server-utilities-statements-go
+type batchSplitter interface {
+	splitter() []byte
+}
+
+var (
+	_ helper = &mySQL{}
+	_ helper = &postgreSQL{}
+	_ helper = &sqlite{}
+	_ helper = &sqlserver{}
+)
+
+type baseHelper struct{}
+
+func (baseHelper) init(_ *sql.DB) error {
+	return nil
+}
+
+func (baseHelper) quoteKeyword(str string) string {
+	return fmt.Sprintf(`"%s"`, str)
+}
+
+func (baseHelper) whileInsertOnTable(_ *sql.Tx, _ string, fn func() error) error {
+	return fn()
+}
+
+func (baseHelper) isTableModified(_ queryable, _ string) (bool, error) {
+	return true, nil
+}
+
+func (baseHelper) afterLoad(_ queryable) error {
+	return nil
+}