Artifact [c02ecbea86]

Artifact c02ecbea8698a7df2d0a509dfbe14451fca83f387bd7e7d7b64a59756805110b:

• File internal/merge/fork.go — part of check-in [f5744359d3] at 2026-04-19 16:30:54 on branch trunk — Initial open source release

  libfossil is a pure-Go implementation of the Fossil SCM, reading and writing the same .fossil SQLite repository format as upstream Fossil.

  This is the first public release of code that previously lived in a private repository. The module path is github.com/danmestas/libfossil and the binary is named libfossil to avoid $PATH collisions with upstream fossil.

  Included: - Repo lifecycle (create, clone), checkout/checkin, timeline, merge, diff, annotate, shun, tag, branch, bisect, stash, undo/redo - Sync-over-HTTP protocol (client and handler) - Two SQLite drivers: modernc (pure Go, default) and ncruces (wasm-capable) - Observer interfaces (SyncObserver, CheckoutObserver) with an optional OpenTelemetry implementation in observer/otel (separate submodule) - Deterministic simulation testing harness with BUGGIFY fault injection - Kong-based embeddable CLI under cli/ and a standalone binary under cmd/libfossil/ (user: [email protected], size: 2902) [annotate] [blame] [check-ins using]

package merge

import "github.com/danmestas/libfossil/internal/repo"

func init() { Register(&ConflictFork{}) }

// ConflictFork preserves all divergent versions without merging.
// Used for offline-first scenarios where conflicts accumulate.
// Stores references in a conflict table (Fossil-idiomatic schema).
type ConflictFork struct{}

func (c *ConflictFork) Name() string { return "conflict-fork" }

func (c *ConflictFork) Merge(base, local, remote []byte) (*Result, error) {
	// Don't merge — preserve all versions. The CLI writes to the conflict table.
	return &Result{
		Content: local,
		Clean:   false,
		Conflicts: []Conflict{{
			Local:  local,
			Remote: remote,
			Base:   base,
		}},
	}, nil
}

// EnsureConflictTable creates the conflict table if it doesn't exist.
// Follows Fossil conventions: REFERENCES blob for rids, julianday REAL for timestamps.
func EnsureConflictTable(r *repo.Repo) error {
	if r == nil {
		panic("merge.EnsureConflictTable: r must not be nil")
	}
	_, err := r.DB().Exec(`CREATE TABLE IF NOT EXISTS conflict(
		cid INTEGER PRIMARY KEY,
		filename TEXT NOT NULL,
		base_rid INTEGER REFERENCES blob,
		local_rid INTEGER REFERENCES blob,
		remote_rid INTEGER REFERENCES blob,
		mtime REAL NOT NULL
	)`)
	return err
}

// RecordConflictFork inserts a conflict-fork entry.
func RecordConflictFork(r *repo.Repo, filename string, baseRID, localRID, remoteRID int64) error {
	if r == nil {
		panic("merge.RecordConflictFork: r must not be nil")
	}
	if filename == "" {
		panic("merge.RecordConflictFork: filename must not be empty")
	}
	_, err := r.DB().Exec(
		"INSERT INTO conflict(filename, base_rid, local_rid, remote_rid, mtime) VALUES(?, ?, ?, ?, julianday('now'))",
		filename, baseRID, localRID, remoteRID,
	)
	return err
}

// ResolveConflictFork deletes a resolved entry (Fossil convention: delete, don't flag).
func ResolveConflictFork(r *repo.Repo, filename string) error {
	if r == nil {
		panic("merge.ResolveConflictFork: r must not be nil")
	}
	if filename == "" {
		panic("merge.ResolveConflictFork: filename must not be empty")
	}
	_, err := r.DB().Exec("DELETE FROM conflict WHERE filename=?", filename)
	return err
}

// ListConflictForks returns all unresolved conflict-fork entries.
func ListConflictForks(r *repo.Repo) ([]string, error) {
	if r == nil {
		panic("merge.ListConflictForks: r must not be nil")
	}
	// Check if conflict table exists.
	var count int
	err := r.DB().QueryRow("SELECT count(*) FROM sqlite_master WHERE type='table' AND name='conflict'").Scan(&count)
	if err != nil || count == 0 {
		return nil, nil
	}

	rows, err := r.DB().Query("SELECT filename FROM conflict ORDER BY mtime DESC")
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	var names []string
	for rows.Next() {
		var name string
		if err := rows.Scan(&name); err != nil {
			continue
		}
		names = append(names, name)
	}
	return names, rows.Err()
}