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: cmd_juju_dumplogs_test.go
    path of file: ./repos/juju/featuretests
    
    the code of the file until where you have to start completion: // Copyright 2015 Canonical Ltd.
// Licensed under the AGPLv3, see LICENCE file for details.

package featuretests

import (
	"bufio"
	"fmt"
	"os"
	"time"

	"github.com/juju/cmd/v3/cmdtesting"
	"github.com/juju/loggo"
	jc "github.com/juju/testing/checkers"
	gc "gopkg.in/check.v1"

	"github.com/juju/juju/agent"
	"github.com/juju/juju/cmd/jujud/agent/agenttest"
	"github.com/juju/juju/cmd/jujud/dumplogs"
	corelogger "github.com/juju/juju/core/logger"
	"github.com/juju/juju/state"
	"github.com/juju/juju/testing/factory"
	"github.com/juju/juju/version"
)

type dumpLogsCommandSuite struct {
	agenttest.AgentSuite
}

func (s *dumpLogsCommandSuite) SetUpTest(c *gc.C) {
	s.AgentSuite.SetUpTest(c)
}

func (s *dumpLogsCommandSuite) TestRun(c *gc.C) {
	// Create a controller machine and an agent for it.
	m, password := s.Factory.MakeMachineReturningPassword(c, &factory.MachineParams{
		Jobs:  []state.MachineJob{state.JobManageModel},
		Nonce: agent.BootstrapNonce,
	})
	err := m.SetMongoPassword(password)
	c.Assert(err,
    
func (s *dumpLogsCommandSuite) TestRun(c *gc.C) {
	// Create a controller machine and an agent for it.
	m, password := s.Factory.MakeMachineReturningPassword(c, &factory.MachineParams{
		Jobs:  []state.MachineJob{state.JobManageModel},
		Nonce: agent.BootstrapNonce,
	})
	err := m.SetMongoPassword(password)
	c.Assert(err, jc.ErrorIsNil)

	s.PrimeStateAgent(c, m.Tag(), password)

	//  Create multiple environments and add some logs for each.
	st1 := s.Factory.MakeModel(c, nil)
	defer st1.Close()
	st2 := s.Factory.MakeModel(c, nil)
	defer st2.Close()
	states := []*state.State{s.State, st1, st2}

	t := time.Date(2015, 11, 4, 3, 2, 1, 0, time.UTC)
	for _, st := range states {
		w := state.NewDbLogger(st)
		defer w.Close()
		for i := 0; i < 3; i++ {
			err := w.Log([]corelogger.LogRecord{{
				Time:     t,
				Entity:   "machine-42",
				Version:  version.Current,
				Module:   "module",
				Location: "location",
				Level:    loggo.INFO,
				Message:  fmt.Sprintf("%d", i),
				Labels:   []string{"http"},
			}})
			c.Assert(err, jc.ErrorIsNil)
		}
	}

	// Run the juju-dumplogs command
	command := dumplogs.NewCommand()
	context, err := cmdtesting.RunCommand(c, command, "--data-dir", s.DataDir())
	c.Assert(err, jc.ErrorIsNil)

	// Check the log file for each environment
	expectedLog := "machine-42: 2015-11-04 03:02:01 INFO module %d http"
	for _, st := range states {
		logName := context.AbsPath(fmt.Sprintf("%s.log", st.ModelUUID()))
		logFile, err := os.Open(logName)
		c.Assert(err, jc.ErrorIsNil)
		scanner := bufio.NewScanner(logFile)
		for i := 0; scanner.Scan(); i++ {
			c.Assert(scanner.Text(), gc.Equals, fmt.Sprintf(expectedLog, i))
		}
		c.Assert(scanner.Err(), jc.ErrorIsNil)
	}
}