Failed to close mock DB

[pancudaniel7]

Hi,

I am using the datadog sql mock example suite testing testify example and when the db.close() function is called it returns "Failed to close mock DB"

Operating system and Go Version

Issue

Running db.close() I receive "Failed to close mock DB"

Reproduction steps

Execute the suit test example on github using go 1.23.3 darwin/arm64

Expected Result

To close the mock db without errors

Actual Result

"Failed to close mock DB"

[starquake]

I ran into the same problem. I think it's an issue with the example. I always check errors even in testcode, and this convinced me to keep doing that.

When you defer close it will be called after ExpectationsWereMet(). But it's not part of the expectations. Something extra is happening so that's probably why it reports it as an error. So I think in the case of the example the db.Close() and the ExpectationsWereMet() check should both be deferred.

package main

import (
	"fmt"
	"testing"

	"github.com/DATA-DOG/go-sqlmock"
)

// a successful case
func TestShouldUpdateStats(t *testing.T) {
	db, mock, err := sqlmock.New()
	if err != nil {
		t.Fatalf("an error '%s' was not expected when opening a stub database connection", err)
	}
	defer func() {
		// Defer both closing and checking expectations
		if err = db.Close(); err != nil {
			t.Fatalf("error closing db: %v", err)
		}
		if err = mock.ExpectationsWereMet(); err != nil {
			t.Errorf("there were unfulfilled expectations: %s", err)
		}
	}()

	mock.ExpectBegin()
	mock.ExpectExec("UPDATE products").WillReturnResult(sqlmock.NewResult(1, 1))
	mock.ExpectExec("INSERT INTO product_viewers").WithArgs(2, 3).WillReturnResult(sqlmock.NewResult(1, 1))
	mock.ExpectCommit()
	mock.ExpectClose()       // <--- We expect a close now!

	// now we execute our method
	if err = recordStats(db, 2, 3); err != nil {
		t.Errorf("error was not expected while updating stats: %s", err)
	}
}