@@ -16,10 +16,12 @@ type Service interface {
	// Count changes.
	Count(ctx context.Context, repo string, opt ListOptions) (uint64, error)

	// Get a change.
	Get(ctx context.Context, repo string, id uint64) (Change, error)
	// ListCommits lists change commits.
	ListCommits(ctx context.Context, repo string, id uint64) ([]Commit, error)
	// Get a change diff.
	GetDiff(ctx context.Context, repo string, id uint64) ([]byte, error)

	// ListComments lists comments for specified change id.
	ListComments(ctx context.Context, repo string, id uint64, opt *ListCommentsOptions) ([]issues.Comment, error)
@@ -36,10 +38,17 @@ type Change struct {
	Author    users.User
	CreatedAt time.Time
	Replies   int // Number of replies to this change (not counting the mandatory change description comment).
}

type Commit struct {
	SHA        string
	Message    string
	Author     users.User
	AuthorTime time.Time
}

// State represents the change state.
type State string

const (
	// OpenState is when a change is open.

@@ -123,10 +123,14 @@ func state(status string) changes.State {
	default:
		panic("unreachable")
	}
}

func (s service) ListCommits(ctx context.Context, _ string, id uint64) ([]changes.Commit, error) {
	return nil, fmt.Errorf("ListCommits: not implemented")
}

func (s service) GetDiff(ctx context.Context, _ string, id uint64) ([]byte, error) {
	diff, _, err := s.cl.Changes.GetPatch(fmt.Sprint(id), "current", &gerrit.PatchOptions{
		Path: "src", // TODO.
	})
	if err != nil {

@@ -203,10 +203,32 @@ func (s service) Get(ctx context.Context, rs string, id uint64) (changes.Change,
		Author:    ghActor(pr.Author),
		CreatedAt: pr.CreatedAt.Time,
	}, nil
}

func (s service) ListCommits(ctx context.Context, rs string, id uint64) ([]changes.Commit, error) {
	repo, err := ghRepoSpec(rs)
	if err != nil {
		// TODO: Map to 400 Bad Request HTTP error.
		return nil, err
	}
	cs, _, err := s.clV3.PullRequests.ListCommits(ctx, repo.Owner, repo.Repo, int(id), nil)
	if err != nil {
		return nil, err
	}
	var commits []changes.Commit
	for _, c := range cs {
		commits = append(commits, changes.Commit{
			SHA:        *c.SHA,
			Message:    *c.Commit.Message,
			Author:     ghUser(c.Author),
			AuthorTime: *c.Commit.Author.Date,
		})
	}
	return commits, nil
}

func (s service) GetDiff(ctx context.Context, rs string, id uint64) ([]byte, error) {
	repo, err := ghRepoSpec(rs)
	if err != nil {
		// TODO: Map to 400 Bad Request HTTP error.
		return nil, err

@@ -104,10 +104,14 @@ func (s service) Count(_ context.Context, repo string, opt changes.ListOptions)
func (s service) Get(ctx context.Context, _ string, id uint64) (changes.Change, error) {
	// TODO.
	return changes.Change{}, fmt.Errorf("Get: not implemented")
}

func (s service) ListCommits(ctx context.Context, _ string, id uint64) ([]changes.Commit, error) {
	return nil, fmt.Errorf("ListCommits: not implemented")
}

func (s service) GetDiff(ctx context.Context, _ string, id uint64) ([]byte, error) {
	// TODO.
	return nil, fmt.Errorf("GetDiff: not implemented")
}