Gorm delete with clauses sqlmock 测试

Question

I have a Gorm delete with the returning result:

expirationDate := time.Now().UTC().Add(-(48 * time.hour))
var deletedUsers Users
res := gormDB.WithContext(ctx).
    Table("my_users").
    Clauses(clause.Returning{Columns: []clause.Column{{Name: "email"}}}).
    Where("created_at < ?", expirationDate).
    Delete(&deletedUsers)

Now the test with clauses always fails. eg :

sqlMock.ExpectExec(`DELETE`)
    .WithArgs(expirationDate)
    .WillReturnResult(sqlmock.NewResult(1, 1))

Receiving error:

"call to Query 'DELETE FROM "my_users" WHERE created_at < $1 RETURNING "email"' with args [{Name: Ordinal:1 Value:2023-01-18 06:15:34.694274 +0000 UTC}], was not expected, next expectation is: ExpectedExec => expecting Exec or ExecContext which:\n - matches sql: 'DELETE'\n - is with arguments:\n 0 - 2023-01-18 06:15:34.694274 +0000 UTC\n - should return Result having:\n LastInsertId: 1\n RowsAffected: 1"

I tried many other sqlMock expectations, but they have a similar issue. Also, we don't have a return value in ExpectExec, only in ExpectQuery... Any chance someone has to test the Gorm query with the Clauses?

Answer 1

I was able to successfully manage what you need. First, let me share the files I wrote, and then I'll walk you through all of the relevant changes. The files are repo.go for production and repo_test.go for the test code.

repo.go

package gormdelete

import (
    "context"
    "time"

    "gorm.io/gorm"
    "gorm.io/gorm/clause"
)

type Users struct {
    Email string
}

func Delete(ctx context.Context, gormDB *gorm.DB) error {
    expirationDate := time.Now().UTC().Add(-(48 * time.Hour))

    var deletedUsers Users
    res := gormDB.WithContext(ctx).Table("my_users").Clauses(clause.Returning{Columns: []clause.Column{{Name: "email"}}}).Where("created_at < ?", expirationDate).Delete(&deletedUsers)
    if res.Error != nil {
        return res.Error
    }
    return nil
}

As you didn't provide the full file I tried to guess what was missing.

repo_test.go

package gormdelete

import (
    "context"
    "database/sql/driver"
    "testing"
    "time"

    "github.com/DATA-DOG/go-sqlmock"
    "github.com/stretchr/testify/assert"
    "gorm.io/driver/postgres"
    "gorm.io/gorm"
)

// this is taken directly from the docs
// https://github.com/DATA-DOG/go-sqlmock#matching-arguments-like-timetime
type AnyTime struct{}

// Match satisfies sqlmock.Argument interface
func (a AnyTime) Match(v driver.Value) bool {
    _, ok := v.(time.Time)
    return ok
}

func TestDelete(t *testing.T) {
    db, mock, err := sqlmock.New()
    if err != nil {
        t.Fatalf("an error was not expected: %v", err)
    }

    conn, _ := db.Conn(context.Background())
    gormDb, err := gorm.Open(postgres.New(postgres.Config{
        Conn: conn,
    }))

    row := sqlmock.NewRows([]string{"email"}).AddRow("test@example.com")
    mock.ExpectBegin()
    mock.ExpectQuery("DELETE FROM \"my_users\" WHERE created_at < ?").WithArgs(AnyTime{}).WillReturnRows(row)
    mock.ExpectCommit()

    err = Delete(context.Background(), gormDb)

    assert.Nil(t, err)
    if err = mock.ExpectationsWereMet(); err != nil {
        t.Errorf("not all expectations were met: %v", err)
    }
}

Here, there are more changes that it's worth mentioning:

1. I instantiated the AnyTime as per the documentation (you can see the link in the comment).
2. Again, I guessed the setup of the db , mock , and gormDb but I think it should be more or less the same.
3. I switch the usage of ExpectExec to ExpectQuery as we'll have back a result set as specified by the Clauses method in your repo.go file.
4. You've to wrap the ExpectQuery within an ExpectBegin and an ExpectCommit .
5. Finally, pay attention to the difference in how the driver expects the parameters in the SQL statement. In the production code, you can choose to use ? or $1 . However, in the test code, you can only use the ? otherwise it won't match the expectations.

Hope to help a little bit, otherwise, let me know!