Artifact [6abfc69693]

Artifact 6abfc6969374617c9d2961afd659243b17b08960e5e9bb46047095255269227e:

• File internal/deck/deck.go — part of check-in [0902561005] at 2026-10-12 17:44:22 on branch main — fix(deck): re-encode present-but-empty values and keep timestamp precision (#272) (#338)

  Marshal dropped a present-but-empty C comment, N mimetype or T value, a bare P card and an empty W body, and wrote D to the millisecond and E to the second, so an artifact carrying any of those did not round-trip through Parse and Marshal.

  Carry the presence of a C, N or P card, and of a T value, in unexported Deck/TagCard fields that Parse sets and Marshal reads, and re-emit the W card whenever its body is non-nil (a parsed empty body is a non-nil empty slice). The public API is unchanged: a caller that sets a non-empty value still has it marshalled. Write the D and E timestamps at their writer precision -- millisecond and second -- extended to keep whatever finer fraction the parser read, so a sub-second timestamp survives the round trip. Remove the three FuzzArtifactRoundTrip knownLosses these fixes retire. (user: [email protected], size: 3030) [annotate] [blame] [check-ins using]

package deck

import "time"

type ArtifactType int

const (
	Checkin    ArtifactType = iota
	Wiki
	Ticket
	Event
	Cluster
	ForumPost
	Attachment
	Control
)

type Deck struct {
	Type ArtifactType
	A    *AttachmentCard
	B    string
	C    string
	D    time.Time
	E    *EventCard
	F    []FileCard
	G    string
	H    string
	I    string
	J    []TicketField
	K    string
	L    string
	M    []string
	N    string
	P    []string
	Q    []CherryPick
	R    string
	T    []TagCard
	// U tracks the check-in user with three distinct states, mirroring
	// fossil's src/manifest.c:1008-1016 U-card handling:
	//   - nil: no U-card in the manifest at all (SQL NULL at crosslink time)
	//   - non-nil, "anonymous": U-card present but empty (resolved at parse
	//     time, matching canonical fossil's own substitution)
	//   - non-nil, non-empty: U-card present with a login name
	// Deliberately *string rather than string: a bare "" cannot represent
	// "absent" and "present-but-empty" at once, which previously collapsed
	// both into the same stored value. See User for constructing literals.
	U    *string
	W    []byte
	Z    string

	// cPresent, nPresent and pPresent record that a C, N or P card was present
	// in the parsed manifest even when its value is empty, so Marshal can
	// re-emit a present-but-empty C/N comment or a bare P card and the artifact
	// round-trips. They are unexported because they matter only to the parse ->
	// marshal round trip: a caller building a Deck sets a non-empty value, which
	// Marshal still emits on its own, and the W card uses nil versus a non-nil
	// empty slice for the same distinction. See §4.2 (empty trailing token) and
	// §4.7.13.
	cPresent bool
	nPresent bool
	pPresent bool
}

type FileCard struct {
	Name    string
	UUID    string
	Perm    string
	OldName string
}

type TagCard struct {
	Type  TagType
	Name  string
	UUID  string
	Value string
	// valuePresent records that a value token was present even when empty, so a
	// parsed `T +x * ` round-trips with its trailing space. Unexported for the
	// same reason as Deck.cPresent: Marshal emits a non-empty Value regardless.
	valuePresent bool
}

type TagType byte

const (
	TagSingleton   TagType = '+'
	TagPropagating TagType = '*'
	TagCancel      TagType = '-'
)

type CherryPick struct {
	IsBackout bool
	Target    string
	Baseline  string
}

type AttachmentCard struct {
	Filename string
	Target   string
	Source   string
}

type EventCard struct {
	Date time.Time
	UUID string
}

type TicketField struct {
	Name  string
	Value string
}

// User returns a pointer to s for constructing Deck.U. Go forbids taking
// the address of a string literal directly, so composite literals go
// through this instead of Deck{U: &s}. Deliberately *string rather than a
// named struct type: passing *string straight to database/sql lets a nil
// argument bind SQL NULL and a non-nil one deref to its value automatically
// (see Deck.U), so crosslink/rebuild call sites need no special-casing.
func User(s string) *string {
	return &s
}