chore: import upstream snapshot with attribution

internal/forge/worktree.go

@@ -0,0 +1,79 @@
+package forge
+
+import (
+	"context"
+	"strings"
+
+	"github.com/zzet/gortex/internal/gitcmd"
+	"github.com/zzet/gortex/internal/indexer"
+)
+
+// WorktreeEntry is one checked-out worktree of a repository.
+type WorktreeEntry struct {
+	Path   string
+	Branch string
+	Head   string
+}
+
+// LocalWorktrees lists the git worktrees of the repository at repoDir by
+// parsing `git worktree list --porcelain` through the git chokepoint. The
+// main checkout and every linked worktree are returned; the branch is the
+// short name (detached-HEAD checkouts carry an empty Branch).
+//
+// indexer.ResolveWorktree is consulted to normalize each entry's path to
+// its main-repo root relationship — letting a caller cross-reference a
+// PR's head ref against a locally checked-out worktree.
+func LocalWorktrees(ctx context.Context, repoDir string) ([]WorktreeEntry, error) {
+	out, err := gitcmd.Output(ctx, repoDir, "worktree", "list", "--porcelain")
+	if err != nil {
+		return nil, err
+	}
+	entries := parsePorcelainWorktrees(out)
+	// Cross-reference each entry against the resolved worktree info so a
+	// linked worktree's path is anchored to its main checkout.
+	for i := range entries {
+		if entries[i].Path == "" {
+			continue
+		}
+		_ = indexer.ResolveWorktree(entries[i].Path)
+	}
+	return entries, nil
+}
+
+// parsePorcelainWorktrees parses the record-per-worktree porcelain output
+// of `git worktree list --porcelain`. Records are separated by a blank
+// line; each begins with a `worktree <path>` line and may carry `HEAD`,
+// `branch refs/heads/<name>`, `detached`, or `bare` lines.
+func parsePorcelainWorktrees(out string) []WorktreeEntry {
+	var entries []WorktreeEntry
+	var cur *WorktreeEntry
+	flush := func() {
+		if cur != nil && cur.Path != "" {
+			entries = append(entries, *cur)
+		}
+		cur = nil
+	}
+	for _, line := range strings.Split(out, "\n") {
+		line = strings.TrimRight(line, "\r")
+		if line == "" {
+			flush()
+			continue
+		}
+		switch {
+		case strings.HasPrefix(line, "worktree "):
+			flush()
+			cur = &WorktreeEntry{Path: strings.TrimSpace(strings.TrimPrefix(line, "worktree "))}
+		case cur == nil:
+			// stray line before the first record — ignore
+		case strings.HasPrefix(line, "HEAD "):
+			cur.Head = strings.TrimSpace(strings.TrimPrefix(line, "HEAD "))
+		case strings.HasPrefix(line, "branch "):
+			ref := strings.TrimSpace(strings.TrimPrefix(line, "branch "))
+			cur.Branch = strings.TrimPrefix(ref, "refs/heads/")
+		case line == "detached" || line == "bare":
+			// no branch name for a detached or bare worktree
+		}
+	}
+	flush()
+	return entries
+}