func PackfilesInfoForRepository()

in internal/git/stats/repository_info.go [427:524]
76 lines of code
22 McCabe index (conditional complexity)

func PackfilesInfoForRepository(ctx context.Context, repo *localrepo.Repo) (PackfilesInfo, error) {
	repoPath, err := repo.Path(ctx)
	if err != nil {
		return PackfilesInfo{}, fmt.Errorf("getting repository path: %w", err)
	}
	packfilesPath := filepath.Join(repoPath, "objects", "pack")

	entries, err := os.ReadDir(packfilesPath)
	if err != nil {
		if errors.Is(err, os.ErrNotExist) {
			return PackfilesInfo{}, nil
		}

		return PackfilesInfo{}, err
	}

	packfilesMetadata := classifyPackfiles(entries)

	var info PackfilesInfo
	for _, entry := range entries {
		entryName := entry.Name()

		switch {
		case hasPrefixAndSuffix(entryName, "pack-", ".pack"):
			size, err := entrySize(entry)
			if err != nil {
				return PackfilesInfo{}, fmt.Errorf("getting packfile size: %w", err)
			}

			info.Count++
			info.Size += size

			metadata := packfilesMetadata[entryName]
			switch {
			case metadata.hasKeep:
				info.KeepCount++
				info.KeepSize += size
			case metadata.hasMtimes:
				info.CruftCount++
				info.CruftSize += size
			}
		case hasPrefixAndSuffix(entryName, "pack-", ".idx"):
			// We ignore normal indices as every packfile would have one anyway, or
			// otherwise the repository would be corrupted.
		case hasPrefixAndSuffix(entryName, "pack-", ".keep"):
			// We classify .keep files above.
		case hasPrefixAndSuffix(entryName, "pack-", ".mtimes"):
			// We classify .mtimes files above.
		case hasPrefixAndSuffix(entryName, "pack-", ".rev"):
			info.ReverseIndexCount++
		case hasPrefixAndSuffix(entryName, "pack-", ".bitmap"):
			bitmap, err := BitmapInfoForPath(filepath.Join(packfilesPath, entryName))
			if err != nil {
				return PackfilesInfo{}, fmt.Errorf("reading bitmap info: %w", err)
			}

			info.Bitmap = bitmap
		case entryName == "multi-pack-index":
			midxInfo, err := MultiPackIndexInfoForPath(filepath.Join(packfilesPath, entryName))
			if err != nil {
				return PackfilesInfo{}, fmt.Errorf("reading multi-pack-index: %w", err)
			}

			info.MultiPackIndex = midxInfo
		case hasPrefixAndSuffix(entryName, "multi-pack-index-", ".bitmap"):
			bitmap, err := BitmapInfoForPath(filepath.Join(packfilesPath, entryName))
			if err != nil {
				return PackfilesInfo{}, fmt.Errorf("reading multi-pack-index bitmap info: %w", err)
			}

			info.MultiPackIndexBitmap = bitmap
		default:
			size, err := entrySize(entry)
			if err != nil {
				if errors.Is(err, os.ErrNotExist) {
					// Unrecognized files may easily be temporary files written
					// by Git. It is expected that these may get concurrently
					// removed, so we just ignore the case where they've gone
					// missing.
					continue
				}

				return PackfilesInfo{}, fmt.Errorf("getting garbage size: %w", err)
			}

			info.GarbageCount++
			info.GarbageSize += size
		}
	}

	lastFullRepack, err := FullRepackTimestamp(repoPath)
	if err != nil {
		return PackfilesInfo{}, fmt.Errorf("reading full-repack timestamp: %w", err)
	}
	info.LastFullRepack = lastFullRepack

	return info, nil
}