diff options
Diffstat (limited to 'internal/calendar')
| -rw-r--r-- | internal/calendar/calendar.go | 76 | ||||
| -rw-r--r-- | internal/calendar/precedence_ef_repro_test.go | 22 |
2 files changed, 86 insertions, 12 deletions
diff --git a/internal/calendar/calendar.go b/internal/calendar/calendar.go index 33706d8..f364321 100644 --- a/internal/calendar/calendar.go +++ b/internal/calendar/calendar.go @@ -35,14 +35,43 @@ func TemporalSlug(date time.Time, sel Selection) string { func computeEF(date time.Time, sel Selection, layers []Layer) LiturgicalDay { td := temporalEF(date) merged := mergeLayers(layers) - cands := []candidate{{Cel: td.Cel, Temporal: true, Season: td.Season}} + year := date.Year() + // occupiedByRank reports whether some OTHER fixed-date sanctoral + // celebration whose rank passes `allowed` resolves onto d this year. + // transferIfImpededEF uses this at two different thresholds: class 1 + // only, to decide whether a candidate is impeded in the first place (a + // class-2 occupant never impedes a class-1 feast -- class 1 always beats + // class 2 outright, no tie exists); and class 1 OR 2, for RG 96's "next + // day that is not I or II class" once a transfer is already under way + // (e.g. the Visitation, 2 July, blocking the Precious Blood's transfer + // off 1 July in 2011). + occupiedByRank := func(d time.Time, exceptSlug string, allowed func(Rank) bool) bool { + for slug2, rc2 := range merged { + if slug2 == exceptSlug { + continue + } + cel2 := buildCelebration(slug2, rc2) + if !allowed(cel2.Rank) { + continue + } + if when2, ok := celebrationDate(cel2, year, sel); ok && sameDay(when2, d) { + return true + } + } + return false + } + isClass1 := func(r Rank) bool { return r == RankClass1 } + isClass1Or2 := func(r Rank) bool { return r == RankClass1 || r == RankClass2 } + cands := []candidate{{Cel: td.Cel, Temporal: true, Season: td.Season, Sunday: td.Sunday}} for slug, rc := range merged { cel := buildCelebration(slug, rc) - when, ok := celebrationDate(cel, date.Year(), sel) + when, ok := celebrationDate(cel, year, sel) if !ok { continue } - effective := transferIfImpededEF(cel, when) + effective := transferIfImpededEF(cel, when, + func(d time.Time) bool { return occupiedByRank(d, cel.Slug, isClass1) }, + func(d time.Time) bool { return occupiedByRank(d, cel.Slug, isClass1Or2) }) if sameDay(effective, date) { cands = append(cands, candidate{Cel: cel, Temporal: false, Season: td.Season}) } @@ -199,12 +228,29 @@ func transferIfImpeded(cel Celebration, when time.Time, sel Selection) time.Time // transferIfImpededEF moves an EF sanctoral feast off a date it cannot be kept // on. Two rules cover the 1962 cases: All Souls, when Nov 2 is a Sunday, is -// transferred to the Monday (Nov 3); and a I class feast impeded by a I class -// temporal day (Holy Week, the Easter octave) is pushed forward to the next free -// day — for the Annunciation in Holy Week this lands on the Monday after Low -// Sunday, past the whole privileged octave. Lower-rank feasts are only -// commemorated, never transferred. -func transferIfImpededEF(cel Celebration, when time.Time) time.Time { +// transferred to the Monday (Nov 3); and a I class feast genuinely impeded is +// pushed forward to the next day that is itself neither I nor II class (RG +// 96: "the next following day that is not I or II class"). Lower-rank feasts +// are only commemorated, never transferred (RG 95). +// +// occupiedByClass1 and occupiedByClass1Or2 are deliberately different +// thresholds, not the same check reused twice: +// - a candidate is impeded IN THE FIRST PLACE only by a genuine class-1 +// collision -- the temporal office of `when` is itself I class (a Sunday +// of Advent/Lent/Passiontide, Holy Week, a named I-class feast), or +// another FIXED I-class sanctoral feast already sits on `when` (RG +// 97/98). A II-class occupant, temporal or sanctoral, never impedes a +// I-class feast at all -- I class always outranks II class outright, no +// tie-break is even reached -- so using the wider I-OR-II threshold here +// would (and, before this fix, did: e.g. All Saints, 1 Nov, was wrongly +// bumped to 3 Nov merely for landing on an ordinary II-class Sunday it +// would have won outright) send an unimpeded I-class feast on an +// unnecessary walk. +// - once a transfer is under way, the DESTINATION must avoid landing on +// ANY I- or II-class day (RG 96's own wider "not I or II class" text) -- +// e.g. the Visitation, 2 July, blocks the Precious Blood's transfer off 1 +// July in 2011, and 3 July's ordinary Sunday blocks it a second time. +func transferIfImpededEF(cel Celebration, when time.Time, occupiedByClass1, occupiedByClass1Or2 func(time.Time) bool) time.Time { if when.Month() == time.November && when.Day() == 2 && when.Weekday() == time.Sunday && strings.Contains(cel.Slug, "all-souls") { return when.AddDate(0, 0, 1) @@ -212,11 +258,17 @@ func transferIfImpededEF(cel Celebration, when time.Time) time.Time { if cel.Rank != RankClass1 { return when } - day := when + startTemporal := temporalEF(when) + startImpeded := startTemporal.Cel.Rank == RankClass1 || occupiedByClass1(when) + if !startImpeded { + return when + } + day := when.AddDate(0, 0, 1) for i := 0; i < 30; i++ { b := temporalEF(day) - if precedenceEF(candidate{Cel: b.Cel, Temporal: true, Season: b.Season}) <= 2 { - day = day.AddDate(0, 0, 1) // impeded by a I class temporal day; push forward + band := precedenceEF(candidate{Cel: b.Cel, Temporal: true, Season: b.Season, Sunday: b.Sunday}) + if band <= 3 || occupiedByClass1Or2(day) { + day = day.AddDate(0, 0, 1) // still I- or II-class; keep walking continue } return day diff --git a/internal/calendar/precedence_ef_repro_test.go b/internal/calendar/precedence_ef_repro_test.go index 6c333d0..1f38996 100644 --- a/internal/calendar/precedence_ef_repro_test.go +++ b/internal/calendar/precedence_ef_repro_test.go @@ -43,3 +43,25 @@ func TestJosephYieldsToSundayOfLent(t *testing.T) { } } } + +// TestTransferSkipsBothIAndIIClass: RG 96 -- an impeded I-class feast +// transfers to the next day that is NOT ITSELF I OR II CLASS (not merely "not +// I class"). 2011: the Sacred Heart (Friday after the Corpus Christi octave) +// falls on 1 July and impedes the Precious Blood (also 1 July, fixed). 2 +// July is the Visitation (II class, fixed); 3 July is an ordinary II-class +// Sunday. Both must be skipped; the Precious Blood lands on 4 July, and the +// Visitation is observed, undisplaced, on its own day. +func TestTransferSkipsBothIAndIIClass(t *testing.T) { + if got := efCompute("2011-07-01").Observed.Slug; got != "ef-sacred-heart" { + t.Fatalf("2011-07-01 observed = %q want ef-sacred-heart", got) + } + if got := efCompute("2011-07-02").Observed.Slug; got != "visitation-of-the-blessed-virgin-mary" { + t.Errorf("2011-07-02 observed = %q want visitation-of-the-blessed-virgin-mary (RG 96: the Precious Blood must skip past it, not displace it)", got) + } + if got := efCompute("2011-07-03").Observed.Slug; got != "ef-time-after-pentecost-sunday-3" { + t.Errorf("2011-07-03 observed = %q want ef-time-after-pentecost-sunday-3 (an ordinary II-class Sunday also blocks a I-class transfer)", got) + } + if got := efCompute("2011-07-04").Observed.Slug; got != "precious-blood-of-our-lord-jesus-christ" { + t.Errorf("2011-07-04 observed = %q want precious-blood-of-our-lord-jesus-christ (RG 96: first day that is neither I nor II class)", got) + } +} |