diff options
Diffstat (limited to 'internal/calendar/precedence_ef.go')
| -rw-r--r-- | internal/calendar/precedence_ef.go | 86 |
1 files changed, 72 insertions, 14 deletions
diff --git a/internal/calendar/precedence_ef.go b/internal/calendar/precedence_ef.go index 4fda626..9f5016f 100644 --- a/internal/calendar/precedence_ef.go +++ b/internal/calendar/precedence_ef.go @@ -1,6 +1,9 @@ package calendar -import "sort" +import ( + "sort" + "strings" +) // efRankOrder orders EF (1960) ranks: class-1 highest, then class-2..4, // commemoration, ferial lowest. @@ -22,34 +25,89 @@ func efRankOrder(r Rank) int { } // precedenceEF ranks an EF candidate for occurrence (lower = higher precedence): -// by class first, then a tie-break at equal class (1960 occurrence table). +// by class first, then a tie-break at equal class (RG 91's Table of +// Precedence, read entry-by-entry within each class). // -// The tie-break is asymmetric by season. An ORDINARY feria (per annum, Advent, -// Septuagesima) yields to an equal-class feast — the feast is celebrated and the -// feria commemorated (e.g. St Francis Xavier, Dec 3, on an Advent feria). The -// ferias of Lent and Passiontide are privileged: they outrank an equal-class -// feast, which is only commemorated. Sundays and named temporal feasts likewise -// win their ties. The *2 class spacing means the ±1 tie-break never crosses a -// class boundary. +// The tie-break is asymmetric by season AND, at class 2, by whether the +// temporal day is a Sunday or a privileged FERIA: +// - III/IV class: an ORDINARY feria (per annum, Advent to 16 Dec, +// Septuagesima) yields to an equal-class feast (entries 24/25 above the +// feria) -- the feast is celebrated, the feria commemorated (e.g. St +// Francis Xavier, Dec 3). The ferias of Lent and Passiontide are +// privileged (entry 22, ABOVE entry 24): they outrank an equal-class +// feast, which is only commemorated. +// - II class: an ordinary SUNDAY wins its tie (entry 15, above entry 16's +// feasts) -- but a II-class privileged FERIA (the Ember days, the +// late-Advent 17-23 Dec ferias, entry 18) sits BELOW entry 16 and yields +// to an equal-class feast, the opposite of a Sunday's own tie. This is +// the same table shape as III class's Advent/per-annum ferias, just +// inverted for which II-class temporal days count as "privileged". +// - I class: Sundays (entry 6) and I-class ferias (entry 7, Ash +// Wednesday/Holy Week) both sit above entry 11's feasts, so they always +// win -- there is no I-class "ordinary feria yields" case at all. +// +// The *2 class spacing means the ±1 tie-break never crosses a class boundary. func precedenceEF(c candidate) int { p := (6 - efRankOrder(c.Cel.Rank)) * 2 // class-1 -> 2, ferial -> 12 if c.Temporal { - ordinaryFeria := (c.Cel.Rank == RankClass3 || c.Cel.Rank == RankClass4) && - c.Season != Lent && c.Season != Passiontide - if ordinaryFeria { - p++ // an ordinary feria yields to an equal-class feast + yieldsToFeast := false + switch c.Cel.Rank { + case RankClass3, RankClass4: + yieldsToFeast = c.Season != Lent && c.Season != Passiontide + case RankClass2: + // A II-class Sunday (entry 15) wins; a II-class privileged feria -- + // Ember days, the late-Advent 17-23 Dec ferias (entry 18) -- yields + // to an equal-class feast (entry 16), e.g. St Matthew (21 Sep) + // beating the September Ember Wednesday, or St Thomas (21 Dec) + // beating an Advent late feria. + yieldsToFeast = !c.Sunday + } + if yieldsToFeast { + p++ } else { - p-- // Sundays, named feasts, and penitential ferias win their ties + p-- // Sundays, I-class ferias, and penitential (Lent/Passiontide) ferias win their ties } } else if c.Cel.Class == ClassLord && c.Cel.Rank == RankClass2 { // A II class feast of the Lord takes the place of a II class Sunday it // falls on (unlike a saint's feast, which is only commemorated). Give it // the edge over the Sunday's tie-break bonus. p -= 2 + } else if c.Cel.Rank == RankClass1 && beatsClass1Sunday(c.Cel.Slug) { + // RG 91 entries 4 (Immaculate Conception, Assumption BVM) and 5 + // (Vigil & Octave day of the Nativity) both sit ABOVE entry 6 + // (Sundays of Advent/Lent/Passiontide, Low Sunday) -- unlike an + // ORDINARY I-class feast (entry 11, e.g. St Joseph, the Precious + // Blood), which yields to a I-class Sunday, these win the tie. + // Found while verifying defect 4 (Sunday ranks): before that fix, + // Advent/Lent Sundays were wrongly II class, so these feasts beat + // them outright on base class alone, accidentally right; once + // Sundays became I class the tie-break mattered, and without this + // branch the Sunday would wrongly win. Two live cases in the fixed + // calendar: the Immaculate Conception (8 December) on an Advent + // Sunday, and the Vigil of Christmas (24 December) on Advent IV -- + // the latter is not merely a wrong winner but a WORSE bug without + // this branch: transferIfImpededEF has no way to re-place a + // transfer that crosses the Dec31/Jan1 boundary (celebrationDate + // re-resolves a fixed date using the YEAR OF THE DAY BEING QUERIED, + // so a walk landing in January of the following year can never + // match the query that produced it), so the Vigil simply vanished + // for the year instead of landing on the wrong day. The Assumption + // (15 August) never falls in Advent or Lent, so its own share of + // this branch is citation-complete but not live. + p -= 2 } return p } +// beatsClass1Sunday reports whether slug is one of RG 91's entries 4 or 5 -- +// the Immaculate Conception, the Assumption, or the Vigil of Christmas -- +// all of which sit above entry 6's Sundays in the Table of Precedence. +func beatsClass1Sunday(slug string) bool { + return strings.Contains(slug, "immaculate-conception") || + strings.Contains(slug, "assumption-of-the-blessed-virgin-mary") || + slug == "vigil-of-christmas" +} + // pickEF returns the observed EF celebration and the commemorations, ordered // deterministically by precedence then slug. func pickEF(cands []candidate) (candidate, []candidate) { |