vu/tests/calendar/transfer.test.ts

import { describe, expect, it } from 'vitest';
import { resolveDay } from '../../src/calendar';

describe('transfer mechanism (resolveDay integration)', () => {
  // The Vigil of St. Lawrence (Aug 9) is a real content entry specifically
  // added to exercise this — Aug 9, 2026 is a Sunday, so the vigil (rank
  // 'vigil') can't win or be commemorated there (see
  // commemorations.ts's ordinary-sunday rule) and must transfer backward.
  // Since the August pull, Aug 8 is no longer an empty landing day — Ss.
  // Cyriacus, Largus, and Smaragdus (Semiduplex, a fixed, non-movable
  // date) natively occupy it every year, so the backward-transferred
  // vigil runs into collision.ts's sanctoral-vs-sanctoral rules instead of
  // landing untouched: Semiduplex outranks 'vigil' on the shared
  // FeastClass scale, so Cyriacus wins and the vigil is commemorated
  // rather than displacing him — real transfer+collision interaction, not
  // a data error, same class of finding as July's Apollinaris/Vigil-of-
  // St.-James case.
  it('a vigil impeded by an ordinary Sunday transfers backward to Saturday and collides with the real feast already there', () => {
    const saturday = resolveDay('2026-08-08');
    const sunday = resolveDay('2026-08-09');
    const monday = resolveDay('2026-08-10');

    expect(saturday.winner).toEqual({
      kind: 'sanctoral',
      id: 'ss-cyriacus-largus-and-smaragdus',
      name: 'Ss. Cyriacus, Largus, and Smaragdus, Martyrs',
      nameLa: 'Sancti Cyriacus, Largus et Smaragdus, Martyres',
      rank: 'semiduplex',
    });
    expect(saturday.commemorations).toEqual([
      {
        kind: 'sanctoral',
        id: 'vigil-of-st-lawrence',
        name: 'Vigil of St. Lawrence',
        nameLa: 'Vigilia Sancti Laurentii',
        rank: 'vigil',
        transferredFrom: '2026-08-09',
      },
    ]);

    // The Sunday's own winner is unaffected by the vigil, but St. Romanus
    // (the vigil's own stub secondary, see st-romanus.yml) still surfaces
    // as a commemoration here: he lost his own local clash against the
    // vigil before the vigil transferred away, and that loss stands
    // independently of the transfer -- confirmed against the live
    // reference engine, which shows the same commemoration on this date.
    expect(sunday.winner).toEqual({ kind: 'temporal', id: 'post-pentecost-11' });
    expect(sunday.commemorations).toEqual([
      { kind: 'sanctoral', id: 'st-romanus', name: 'St. Romanus, Martyr', nameLa: 'Sanctus Romanus, Martyr', rank: 'simplex' },
    ]);

    // St. Lawrence's own day (Monday) is unaffected by the backward transfer.
    expect(monday.winner).toEqual({
      kind: 'sanctoral',
      id: 'st-lawrence',
      name: 'St. Lawrence, Martyr',
      nameLa: 'Sanctus Laurentius, Martyr',
      rank: 'duplex-2-classis',
    });
  });

  // Originally found via real data (the May sanctoral pull): a
  // transferred-in candidate was blindly winning outright whenever the
  // receiving day's own native winner was temporal, regardless of that
  // day's own precedence category — so a transferred-in Simplex was
  // overwriting Trinity Sunday itself instead of going through the same
  // ordinary-Sunday rule a native candidate would have. That fix (in
  // applyIncomingTransfer) is unchanged and still covered here, but the
  // concrete St. Felix I / Trinity Sunday scenario that first surfaced it
  // no longer demonstrates a *transfer* at all: since the octave
  // mechanism (calendar/octaves.ts) was added, Pentecost's own Ember
  // Saturday is no longer classified `privileged-feria-major` (see
  // data/calendar/temporal-categories.yml), so Felix now wins his own day
  // outright under the permissive `ordinary-feria` default — then gets
  // caught and commemorated in place by Pentecost's octave itself
  // (threshold: duplex), never even reaching a transfer. He simply
  // doesn't appear on Trinity Sunday at all anymore. Kept here anyway as
  // a still-useful demonstration of the octave layer's own override path.
  it("St. Felix I, below Pentecost's octave threshold, is commemorated in place on his own day rather than transferring anywhere", () => {
    const saturday = resolveDay('2026-05-30');
    const sunday = resolveDay('2026-05-31');

    expect(saturday.winner).toEqual({ kind: 'temporal', id: 'pentecost-sunday' });
    expect(saturday.commemorations).toEqual([
      { kind: 'sanctoral', id: 'st-felix-i', name: 'St. Felix I, Pope and Martyr', nameLa: 'Sanctus Felix I, Papa et Martyr', rank: 'simplex' },
      { kind: 'octave', id: 'pentecost-sunday', name: 'Pentecost', nameLa: 'Dominica Pentecostes' },
    ]);

    // Felix doesn't reach Trinity Sunday at all now. Trinity Sunday 2026
    // (May 31) is also the Queenship of the Blessed Virgin Mary's own
    // fixed day (Duplex II Classis). Trinity Sunday used to be modeled as
    // plain `ordinary-sunday` (no special first-class standing of its
    // own), so the Duplex+ Queenship won outright there -- fixed
    // 2026-09-04 with a real `trinity-sunday` temporal-feast record,
    // `unconditional: true` (a principal Sunday shouldn't lose to a
    // same-rank fixed-date collision, same shape as christ-the-king.yml).
    // Trinity Sunday now wins outright; the Queenship, the day's own
    // plain temporal id, and Pentecost's octave are all commemorated in
    // return.
    expect(sunday.winner).toEqual({ kind: 'temporal', id: 'trinity-sunday' });
    expect(sunday.commemorations).toEqual([
      { kind: 'temporal', id: 'post-pentecost-01' },
      { kind: 'octave', id: 'pentecost-sunday', name: 'Pentecost', nameLa: 'Dominica Pentecostes' },
      { kind: 'sanctoral', id: 'queenship-of-the-bvm', name: 'The Queenship of the Blessed Virgin Mary', nameLa: 'Beata Maria Virgo Regina', rank: 'duplex-2-classis' },
    ]);
  });
});

// Anything impeded anywhere from Palm Sunday through Low Sunday
// (2026-09-01: found real, live-verified precedence bugs in exactly this
// area) doesn't cascade day-by-day looking for the next free day — per
// direct instruction, that's not this app's mechanism (it already has
// real precedent for stacking commemorations, and rejected both a
// same-day batch and an open-ended search). Instead: only candidates at
// or above `EASTER_OCTAVE_BACKLOG_FLOOR` (duplex-majus) are worth
// carrying forward at all — anything weaker simply lapses for the year,
// no trace, same as it already gets none within the span itself. Of
// those that clear the floor, the Nth day after Low Sunday celebrates
// the Nth one (native-date order), winning outright — no rank fight —
// and demoting whatever would have natively been there to a
// commemoration. See calendar/index.ts's `applyEasterOctaveBacklog`.
describe('the Easter-octave backlog (Palm Sunday through Low Sunday)', () => {
  it('2033: nothing impeded that year clears the duplex-majus floor, so the backlog is empty and every impeded candidate simply lapses', () => {
    // Easter 2033 is Apr 17, Low Sunday Apr 24. Every candidate vu's own
    // calendar puts inside that span this year (St. Leo I, Duplex;
    // St. Hermenegild, Semiduplex; Ss. Tiburtius/Valerian/Maximus,
    // Simplex; St. Anselm, Duplex; Ss. Soter & Caius, Semiduplex;
    // St. George, Semiduplex; St. Fidelis of Sigmaringen, Duplex) is
    // below duplex-majus.
    const holyMonday = resolveDay('2033-04-11');
    // Monday of Holy Week now has its own real winner id (see
    // calendar/movable-feasts.ts's Passiontide-day override, 2026-09-06)
    // rather than inheriting Palm Sunday's own coarse id — the override
    // mechanism pushes a `{kind:'temporal', id:'palm-sunday'}`
    // commemoration for the coarse id it replaces, same shape every other
    // movable feast (Ascension, Corpus Christi) already does; harmless,
    // since day-label.ts's collectCommemorations deliberately drops any
    // commemoration whose id equals the plain governing weekday.
    expect(holyMonday.winner).toEqual({ kind: 'temporal', id: 'monday-holy-week' });
    expect(holyMonday.commemorations).toEqual([{ kind: 'temporal', id: 'palm-sunday' }]);
    expect(holyMonday.transferredAway?.candidate.id).toBe('st-leo-i');

    for (const afterLowSunday of ['2033-04-25', '2033-04-26', '2033-04-27', '2033-04-28', '2033-04-29']) {
      const day = resolveDay(afterLowSunday);
      const ids = ['st-leo-i', 'st-hermenegild', 'ss-tiburtius-valerian-and-maximus', 'st-anselm', 'ss-soter-and-caius', 'st-george', 'st-fidelis-of-sigmaringen'];
      expect(day.commemorations.some((c) => c.kind === 'sanctoral' && ids.includes(c.id))).toBe(false);
      expect(day.winner.kind === 'sanctoral' ? ids.includes(day.winner.id) : false).toBe(false);
    }
  });

  it('2035: three candidates clear the floor (St. Benedict, St. Gabriel the Archangel, the Annunciation) and land on the 1st/2nd/3rd day after Low Sunday, in native-date order, each demoting that day\'s own native winner to a commemoration', () => {
    // Easter 2035 is Mar 25 (the Annunciation's own fixed date), Low
    // Sunday Apr 1. St. Benedict (native Mar 21, Duplex I. classis),
    // St. Gabriel the Archangel (native Mar 24, Duplex majus), and the
    // Annunciation (native Mar 25, Duplex I. classis) are all impeded
    // and all clear the floor — live-verified 2026-09-01 that the
    // Annunciation herself gets zero commemoration anywhere in the span.
    const easterSunday = resolveDay('2035-03-25');
    expect(easterSunday.winner).toEqual({ kind: 'temporal', id: 'easter-sunday' });
    expect(easterSunday.transferredAway?.candidate.id).toBe('annunciation');
    for (const impededDate of ['2035-03-21', '2035-03-24', '2035-03-26', '2035-03-29', '2035-04-01']) {
      const day = resolveDay(impededDate);
      expect(day.commemorations.some((c) => c.kind === 'sanctoral' && c.id === 'annunciation')).toBe(false);
    }

    const day1 = resolveDay('2035-04-02');
    expect(day1.winner).toEqual({
      kind: 'sanctoral',
      id: 'st-benedict',
      name: 'St. Benedict, Abbot (Transitus)',
      nameLa: 'Sanctus Benedictus, Abbas (Transitus)',
      rank: 'duplex-1-classis',
      transferredFrom: '2035-03-21',
    });
    expect(day1.commemorations.some((c) => c.kind === 'sanctoral' && c.id === 'st-francis-of-paola')).toBe(true);

    const day2 = resolveDay('2035-04-03');
    expect(day2.winner).toEqual({
      kind: 'sanctoral',
      id: 'st-gabriel-archangel',
      name: 'St. Gabriel the Archangel',
      nameLa: 'Sanctus Gabriel Archangelus',
      rank: 'duplex-majus',
      transferredFrom: '2035-03-24',
    });

    const day3 = resolveDay('2035-04-04');
    expect(day3.winner).toEqual({
      kind: 'sanctoral',
      id: 'annunciation',
      name: 'The Annunciation of the Blessed Virgin Mary',
      nameLa: 'Annuntiatio Beatæ Mariæ Virginis',
      rank: 'duplex-1-classis',
      transferredFrom: '2035-03-25',
    });
    expect(day3.commemorations.some((c) => c.kind === 'sanctoral' && c.id === 'st-isidore-of-seville')).toBe(true);

    // The backlog is exhausted after 3 days -- the 4th day after Low
    // Sunday resolves with no override at all.
    const day4 = resolveDay('2035-04-05');
    expect(day4.winner.kind === 'sanctoral' ? day4.winner.transferredFrom : undefined).toBeUndefined();
  });
});