Function fakeSessionID

internal/app/testhelpers_test.go:59–83

fakeSessionID makes a deterministic v4-shaped UUID derived from slug. Used by insertTask to satisfy the session-id invariant on non-backlog rows without entangling tests with real Claude session lifecycles. The format passes sessionUUIDRe so tests that pin --session-id-style behavior keep working.

(slug string)

// session lifecycles. The format passes sessionUUIDRe so tests that
// pin --session-id-style behavior keep working.
func fakeSessionID(slug string) string {
	// FNV-64 hash → 16 hex chars, padded to 32 for v4 layout.
	const fnvOff = 0xcbf29ce484222325
	const fnvPri = 0x100000001b3
	h := uint64(fnvOff)
	for _, b := range []byte(slug) {
		h ^= uint64(b)
		h *= fnvPri
	}
	// Build "xxxxxxxx-xxxx-4xxx-8xxx-xxxxxxxxxxxx" from one hash + slug filler.
	first := fmt.Sprintf("%016x", h)
	// Use the slug bytes (zero-padded) as additional entropy for the
	// last 12 chars so distinct slugs that hash-collide still differ.
	pad := slug
	for len(pad) < 12 {
		pad += "0"
	}
	tailRaw := []byte(pad)[:12]
	for i, b := range tailRaw {
		// Force into hex range.
		tailRaw[i] = "0123456789abcdef"[uint(b)%16]
	}
	tail := string(tailRaw)
	return fmt.Sprintf("%s-%s-4%s-8%s-%s", first[:8], first[8:12], first[12:15], first[15:16]+first[0:2], tail)
}