You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: mssql_test.go
    path of file: ./repos/vault/plugins/database/mssql
    
    the code of the file until where you have to start completion: // Copyright (c) HashiCorp, Inc.
// SPDX-License-Identifier: BUSL-1.1

package mssql

import (
	"context"
	"database/sql"
	"fmt"
	"reflect"
	"regexp"

    
func TestDeleteUserContainedDB(t *testing.T) {
	cleanup, connURL := mssqlhelper.PrepareMSSQLTestContainer(t)
	defer cleanup()

	dbUser := "vaultuser"
	initPassword := "p4$sw0rd"

	initReq := dbplugin.InitializeRequest{
		Config: map[string]interface{}{
			"connection_url": connURL,
			"contained_db":   true,
		},
		VerifyConnection: true,
	}

	db := new()

	dbtesting.AssertInitializeCircleCiTest(t, db, initReq)
	defer dbtesting.AssertClose(t, db)

	err := createTestMSSQLUser(connURL, dbUser, initPassword, testMSSQLContainedLogin)
	if err != nil {
		t.Fatalf("Failed to create user: %s", err)
	}

	assertCredsExist(t, connURL, dbUser, initPassword)

	deleteReq := dbplugin.DeleteUserRequest{
		Username: dbUser,
	}

	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
	defer cancel()
	deleteResp, err := db.DeleteUser(ctx, deleteReq)
	if err != nil {
		t.Fatalf("Failed to delete user: %s", err)
	}

	// Protect against future fields that aren't specified
	expectedResp := dbplugin.DeleteUserResponse{}
	if !reflect.DeepEqual(deleteResp, expectedResp) {
		t.Fatalf("Fields missing from expected response: Actual: %#v", deleteResp)
	}

	assertContainedDBCredsDoNotExist(t, connURL, dbUser)
}