git

type ClaimOrigin interface {
	ListRefs(ctx context.Context, pattern string) ([]RemoteRef, error)
	FetchCommits(ctx context.Context, shas []string) error
	ReadCommitMessage(ctx context.Context, sha string) ([]byte, error)
}

type ClaimRef struct {
	Ref        string `json:"ref"`
	SHA        string `json:"sha"`
	Cluster    string `json:"cluster"`
	TaskID     string `json:"task_id"`
	LeaseUntil string `json:"lease_until"`
}

type ClaimRefRequest struct {
	ExpectedSHA string `json:"expected_sha"`
	Cluster     string `json:"cluster"`
	TaskID      string `json:"task_id"`
	LeaseUntil  string `json:"lease_until"`
}

type ConflictResolver interface {
	Resolve(ctx context.Context, conflictedPaths []string) error
}

type Git interface {
	WriteFile(ctx context.Context, path string, content []byte) error
	// WriteFileIfAbsent writes content to path only when no file exists there
	// yet. It returns ErrFileExists (via errors.Is) when path is occupied, and
	// performs no repository modification in that case.
	WriteFileIfAbsent(ctx context.Context, path string, content []byte) error
	DeleteFile(ctx context.Context, path string) error
	ReadFile(ctx context.Context, path string) ([]byte, error)
	ListFiles(ctx context.Context, pattern string) ([]string, error)
	Pull(ctx context.Context) error
	Status(ctx context.Context) (Status, error)
	Clone(ctx context.Context, remoteURL RemoteURL) error
	ConfigureUser(ctx context.Context, name string, email string) error
	ConfigurePackMemory(ctx context.Context) error
	Init(ctx context.Context) error
	// ListClaimRefs returns the claim refs under refs/<prefix>, read live from the
	// origin. All listed commits are fetched in one batched git invocation; when
	// that fetch fails, each commit is fetched on its own. An entry is dropped
	// with one WARN only when a re-list shows its ref vanished or moved; a fetch
	// failure for a ref that still points at the listed sha is returned as an
	// error.
	ListClaimRefs(ctx context.Context, prefix string) ([]ClaimRef, error)
	// PutClaimRef creates or renews refs/<key> with the origin's compare-and-swap.
	// It returns the new commit sha. A lease mismatch returns ErrRefConflict.
	PutClaimRef(ctx context.Context, key string, request ClaimRefRequest) (string, error)
	// DeleteClaimRef deletes refs/<key> with the origin's compare-and-swap.
	// A lease mismatch or an absent ref returns ErrRefConflict.
	DeleteClaimRef(ctx context.Context, key string, expectedSHA string) error
}

type RebaseConflictError struct {
	Path string // conflicted file path, from "CONFLICT (content): Merge conflict in <path>"
}

type RemoteRef struct {
	SHA string
	Ref string
}

type RemoteURL string

type SSHKeyPath string

type Status struct {
	// Clean is true when the working tree has no uncommitted changes.
	Clean bool
	// NoPushPending is true when there are no commits ahead of the remote.
	NoPushPending bool
}