Add versioning to perf SQL database

perf/go/db/db_test.go

Index: perf/go/db/db_test.go
diff --git a/perf/go/db/db_test.go b/perf/go/db/db_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..1927a8856be418b4a90b3deb46e58af3a7605183
--- /dev/null
+++ b/perf/go/db/db_test.go
@@ -0,0 +1,58 @@
+package db
+
+import (
+	"fmt"
+	"os"
+	"testing"
+)
+
+import (
+	// Using 'require' which is like using 'assert' but causes tests to fail.
+	assert "github.com/stretchr/testify/require"
+)
+
+// Connection string to the local MySQL database for testing.
+const MYSQL_DB_OPEN = "root:%s@tcp(localhost:3306)/skia?parseTime=true"
+
+func TestSQLiteVersioning(t *testing.T) {
+	// Initialize without argument to test against SQLite3
+	Init("")
+	assert.False(t, isMySQL)
+	testDBVersioning(t)
+}
+
+func TestMySQLVersioning(t *testing.T) {
+	// Skip this test unless there is an environment variable with the root
+	// password for the local MySQL instance.
+	password := os.Getenv("MYSQL_TESTING_ROOTPW")
+	if password == "" {
+		t.Skip("Skipping versioning tests against MySQL. Set 'MYSQL_TESTING_ROOTPW' to enable tests.")
+	}
+
+	// Initialize to test against local MySQL db
+	Init(fmt.Sprintf(MYSQL_DB_OPEN, password))
+	assert.True(t, isMySQL)
+	testDBVersioning(t)
+}
+
+// Test wether the migration scripts execute.
+func testDBVersioning(t *testing.T) {
+	// get the DB version
+	dbVersion, err := DBVersion()
+	assert.Nil(t, err)
+	maxVersion := MaxDBVersion()
+
+	// downgrade to 0
+	err = Migrate(0)
+	assert.Nil(t, err)
+	dbVersion, err = DBVersion()
+	assert.Nil(t, err)
+	assert.Equal(t, 0, dbVersion)
+
+	// upgrade the the latest version
+	err = Migrate(maxVersion)
+	assert.Nil(t, err)
+	dbVersion, err = DBVersion()
+	assert.Nil(t, err)
+	assert.Equal(t, maxVersion, dbVersion)
+}