feat(snap): add Cleaner

snap/capabilities.go

@@ -7,7 +7,10 @@ import (
 )
 
 // Compile-time interface checks.
-var _ snack.VersionQuerier = (*Snap)(nil)
+var (
+	_ snack.VersionQuerier = (*Snap)(nil)
+	_ snack.Cleaner        = (*Snap)(nil)
+)
 
 // LatestVersion returns the latest stable version of a snap.
 func (s *Snap) LatestVersion(ctx context.Context, pkg string) (string, error) {
@@ -28,3 +31,16 @@ func (s *Snap) UpgradeAvailable(ctx context.Context, pkg string) (bool, error) {
 func (s *Snap) VersionCmp(ctx context.Context, ver1, ver2 string) (int, error) {
 	return versionCmp(ctx, ver1, ver2)
 }
+
+// Autoremove is a no-op for snap. Snaps are self-contained and do not
+// have orphan dependencies.
+func (s *Snap) Autoremove(ctx context.Context, opts ...snack.Option) error {
+	return autoremove(ctx, opts...)
+}
+
+// Clean removes old disabled snap revisions to free disk space.
+func (s *Snap) Clean(ctx context.Context) error {
+	s.Lock()
+	defer s.Unlock()
+	return clean(ctx)
+}

snap/snap_linux.go

@@ -232,6 +232,48 @@ func versionCmp(_ context.Context, ver1, ver2 string) (int, error) {
 	return semverCmp(ver1, ver2), nil
 }
 
+// autoremove is a no-op for snap. Snaps are self-contained and do not
+// have orphan dependencies.
+func autoremove(_ context.Context, _ ...snack.Option) error {
+	return nil
+}
+
+// clean removes old disabled snap revisions to free disk space.
+// It runs `snap list --all` to find disabled revisions, then removes
+// each one with `snap remove --revision=<rev> <name>`.
+func clean(ctx context.Context) error {
+	out, err := run(ctx, []string{"list", "--all"})
+	if err != nil {
+		return fmt.Errorf("snap clean: %w", err)
+	}
+	// Parse output for disabled revisions
+	// Header: Name  Version  Rev  Tracking  Publisher  Notes
+	// Disabled snaps have "disabled" in the Notes column
+	lines := strings.Split(out, "\n")
+	for i, line := range lines {
+		if i == 0 { // skip header
+			continue
+		}
+		line = strings.TrimSpace(line)
+		if line == "" {
+			continue
+		}
+		if !strings.Contains(line, "disabled") {
+			continue
+		}
+		fields := strings.Fields(line)
+		if len(fields) < 3 {
+			continue
+		}
+		name := fields[0]
+		rev := fields[2]
+		if _, err := run(ctx, []string{"remove", "--revision=" + rev, name}); err != nil {
+			return fmt.Errorf("snap clean %s rev %s: %w", name, rev, err)
+		}
+	}
+	return nil
+}
+
 func upgradePackages(ctx context.Context, pkgs []snack.Target, opts ...snack.Option) (snack.InstallResult, error) {
 	o := snack.ApplyOptions(opts...)
 	var toUpgrade []snack.Target

snap/snap_other.go

@@ -66,6 +66,14 @@ func versionCmp(_ context.Context, _, _ string) (int, error) {
 	return 0, snack.ErrUnsupportedPlatform
 }
 
+func autoremove(_ context.Context, _ ...snack.Option) error {
+	return snack.ErrUnsupportedPlatform
+}
+
+func clean(_ context.Context) error {
+	return snack.ErrUnsupportedPlatform
+}
+
 func upgradePackages(_ context.Context, _ []snack.Target, _ ...snack.Option) (snack.InstallResult, error) {
 	return snack.InstallResult{}, snack.ErrUnsupportedPlatform
 }