feat(ef): the Mass preface, RG 482-499

Item 2 of Phase 3 (celebrant-rubrics-phase1), the bulk of this phase
and the last EF Mass rubric this project scoped: which preface is
said, deferring to seasonal/proper-title rules for the fourteen named
prefaces, then RG 498's Common residual.

RG 482 gives the resolution chain: the Mass's own proper preface,
failing that the seasonal one, failing that Common. Read literally,
RG 484-497 look like fourteen separate rules, but each numbered
rubric's own propria/de-Tempore pair produces the SAME preface
identity either way, so the whole chain collapses into one priority-
ordered decision: title/mystery triggers (Holy Cross, Sacred Heart,
Christ the King, Trinity, St Joseph, BVM, the Nativity octave, the
Apostles, Epiphany), each independent of season, then six seasonal
windows (Nativity, Epiphany, Lent, Holy Cross/Passiontide, Easter,
Ascension, Holy Spirit, Trinity-for-ordinary-Sundays), then Common.

The "one genuinely unproven piece" the design spec worried about --
per-feast proper prefaces extracted from the Missal's propers at scale
-- turned out not to be a large-scale extraction problem at all: every
one of the fourteen propers is a closed, small, subject/slug-keyed
trigger (mirroring Precedence_ef.band's own RG 91 table), not
thousands of individual saints' pages. The one genuine open question
(RG 488, the Chrism Mass) is N/A: this engine resolves one Mass per
civil day and has no separate Chrism-Mass dimension.

Preface is a new kernel type (lib/kernel/preface.ml[i]), not an
EF-specific one, the same placement as Colour/Subject/Mass_formulary:
Liturgical_day.t is parameterised only over season/rank, so any field
it carries generically must live in the kernel even though only EF
constructs a value of it today. Wired exactly as creed/gloria were
(Rite.t.preface, Calendar.ml, Rite_ef.context), but Preface.t option,
not a bare bool: unlike creed/gloria, a preface is said only at a
Mass, and Good Friday (1955-restored Holy Week) resolves an observed
celebration but has no Mass at all -- None is the honest answer there,
and also the neutral value an unimplemented rite returns.

Two priority-order findings only the oracle settled, not derivable
from the Latin text in isolation, both cross-checked against 358
individually classified entries in the FIUV Ordo's own praef column
(test/fixtures/fiuv-ordo-2025-2026.sexp, already captured, wired up
here as a new comparison axis): RG 484(b)'s own "except Masses with a
proper of the divine mysteries or Persons" is narrower than every
other window's implicit exception (an Apostle inside the Nativity
octave is overridden to Nativity; outside it, keeps his own preface
even inside another window); and RG 495's "et votivis" half is live
for the one office this engine models without a votive-Mass dimension
(the Saturday Office of the BVM), which also proved a vigil is not a
"festum" for this purpose (the Assumption's own vigil takes Common,
not BVM, correcting an initial reuse of Precedence_ef.marian_slugs
that had no reason to make that distinction for its own, different
rubric). A third, RG16(a)-shaped fix landed the same way: RG 494(b)'s
own Trinity grant must read the day's TEMPORAL season, not the
celebration that actually won it, or a Class1 feast with no preference
of its own (All Saints) wrongly falls to Common on a Sunday it merely
commemorates.

colitur rubrics gains a sixth TAB-separated column. Domain-wide
1583-9999 exhaustive sweep confirms every Christmastide day resolves
Nativity/Epiphany/Bvm, every Paschaltide day one of its own three
windows or a season-independent title, every Lent day Lent or a
title, and Passiontide legitimately produces Easter exactly once a
year (the Vigil Mass) -- 8416 of the domain's 8417 years, the one
short year being the domain's own upper boundary (the liturgical year
opening in 9999 cannot construct dates in year 10000, a pre-existing
edge this sweep re-confirms rather than a new one).

day/readings verified byte-identical to the branch's own state before
this phase (commit 9c96e0a) across a 455-year sample spanning the
whole domain -- not literally to the v0.10.1 tag, which 22 earlier
commits on this same branch (Phase 1/2, the bissextile shift, the
Rogation colour fix) had already moved past before this phase began.

1 files changed, 386 insertions, 1 deletions

diff --git a/test/test_rubrics_ef.ml b/test/test_rubrics_ef.ml
index d533670..bb3bfed 100644
--- a/test/test_rubrics_ef.ml
+++ b/test/test_rubrics_ef.ml
@@ -746,6 +746,333 @@ let test_exhaustive_gloria_domain_sweep () =
     Alcotest.(check bool) "the full domain reached a real number of Requiem days" true (black > 1_000)
   end
 
+(* ---- RG 482-499, the preface -- see lib/rites/rite_ef/rubrics_ef.ml for
+   the rubric quoted in full and every branch's own citation. One
+   end-to-end test per branch, resolved against REAL calendar dates
+   through the shipped data, the same discipline every other section of
+   this file already follows -- most of these dates were cross-checked
+   directly against the FIUV Ordo's own [praef] column
+   (test/fixtures/fiuv-ordo-2025-2026.sexp) before being pinned here, not
+   merely derived from the Latin text in isolation; see [preface]'s own
+   header for the full account of what that cross-check settled. ---- *)
+
+module Pref = Colitur_kernel.Preface
+
+let preface_on y m d = (day_on y m d).LD.preface
+
+let preface_string_on y m d =
+  match preface_on y m d with Some p -> Pref.to_string p | None -> "-"
+
+let check_preface name expected y m d =
+  Alcotest.(check string) name (Pref.to_string expected) (preface_string_on y m d)
+
+let check_no_preface name y m d = Alcotest.(check string) name "-" (preface_string_on y m d)
+
+(* ---- Good Friday: no Mass at all, [None] -- checked ahead of the
+   Requiem/Black-colour branch (this file's own [preface] header explains
+   why the two need different answers, unlike creed/gloria/te_deum). ---- *)
+let test_preface_good_friday_no_mass () = check_no_preface "Good Friday: no Mass, no preface" 2026 4 3
+
+(* ---- RG 499: the Requiem proxy, the SAME two-member {!Colour.Black}
+   population {!test_colour_black_population_is_exactly_two} already
+   asserts, with Good Friday split out above. ---- *)
+let test_preface_499_all_souls () =
+  check_preface "RG 499: All Souls' Day (transferred)" Pref.Requiem 2025 11 3
+
+(* ---- RG 487(a): the two fixed Holy Cross feast triggers. ---- *)
+let test_preface_487a_exaltation () =
+  check_preface "RG 487(a): the Exaltation of the Holy Cross" Pref.Holy_cross 2026 9 14
+
+let test_preface_487a_precious_blood () =
+  check_preface "RG 487(a): the Most Precious Blood" Pref.Holy_cross 2026 7 1
+
+(* ---- RG 491/492: Sacred Heart, Christ the King -- single named days. ---- *)
+let test_preface_491_sacred_heart () = check_preface "RG 491: the Sacred Heart" Pref.Sacred_heart 2026 6 12
+let test_preface_492_christ_the_king () =
+  check_preface "RG 492: Christ the King" Pref.Christ_the_king 2026 10 25
+
+(* ---- RG 490(a): Ascension Day itself. ---- *)
+let test_preface_490a_ascension_day () = check_preface "RG 490(a): Ascension Day" Pref.Ascension 2026 5 14
+
+(* ---- RG 494(a): Trinity Sunday itself. ---- *)
+let test_preface_494a_trinity_sunday () = check_preface "RG 494(a): Trinity Sunday" Pref.Trinity 2026 5 31
+
+(* ---- RG 496: St Joseph's two feasts. ---- *)
+let test_preface_496_joseph_spouse () = check_preface "RG 496: St Joseph, Spouse of the BVM" Pref.St_joseph 2026 3 19
+let test_preface_496_joseph_workman () = check_preface "RG 496: St Joseph the Workman" Pref.St_joseph 2027 5 1
+
+(* ---- RG 495: a genuine Marian FEAST via [marian_slugs] (the Assumption),
+   and the VOTIVE-shaped BVM Saturday Office via [subject = Bvm] -- the
+   latter is the live witness for RG 495's own "et votivis" half on this
+   engine's data (this file's own [preface] header has the full account,
+   corroborated against the Ordo on 3/10 January 2026). ---- *)
+let test_preface_495_assumption () = check_preface "RG 495: the Assumption (marian_slugs)" Pref.Bvm 2026 8 15
+let test_preface_495_bvm_saturday_office () =
+  check_preface "RG 495: the BVM Saturday Office (subject=Bvm, votive-shaped)" Pref.Bvm 2026 7 11
+
+(* ---- RG 484(a)'s own explicit Purification clause: 2 February, checked
+   as a standalone slug trigger regardless of season -- see [preface]'s
+   own header for why this needed to be independent of the Nativity
+   WINDOW below (2 February is nowhere near it). ---- *)
+let test_preface_484a_purification () = check_preface "RG 484(a): the Purification" Pref.Nativity 2026 2 2
+
+(* ---- RG 484(a)/(b) merged: the Nativity octave window, 25 December-1
+   January, PLUS RG 484(b)'s own extra "2 ad 5 ianuarii" days -- one
+   contiguous window. St Stephen (26 December) is the live witness that
+   this OUTRANKS an ordinary saint's own otherwise-Common preface;
+   {!creed}'s own 475(d) test picks the identical date for the identical
+   "occurring inside a privileged window" shape. ---- *)
+let test_preface_484_nativity_day () = check_preface "RG 484(a): Christmas Day itself" Pref.Nativity 2026 12 25
+let test_preface_484_stephen_in_octave () =
+  check_preface "RG 484(b): St Stephen, occurring within the Nativity octave" Pref.Nativity 2026 12 26
+
+let test_preface_484_jan1_octave_day () =
+  check_preface "RG 484(a): 1 January, the Octave Day" Pref.Nativity 2026 1 1
+
+let test_preface_484b_jan2to5 () =
+  (* 2 January 2026 (a plain Christmastide feria, "ef-christmas-1-friday",
+     confirmed via `colitur day 2026`) -- 3 January that year is the BVM
+     Saturday Office instead (RG 495's own "et votivis" outranking this
+     window, this file's own [test_preface_495_bvm_saturday_office] and
+     [preface]'s own header have the full account), so this date is picked
+     specifically to witness the PLAIN de-Tempore grant, uncomplicated by
+     that override. *)
+  check_preface "RG 484(b): 2 January, the extra de-Tempore days" Pref.Nativity 2026 1 2
+
+(* ---- RG 484(b)'s own NARROWER exception: an Apostle/Evangelist inside
+   the Nativity octave is STILL overridden to [Nativity] (unlike every
+   other window, which an Apostle's own preface outranks -- the next test
+   below). John the Evangelist, 27 December, is the live witness this
+   file's own [preface] header cites. ---- *)
+let test_preface_484b_overrides_apostle_in_octave () =
+  check_preface "RG 484(b): St John the Evangelist, inside the Nativity octave, still [Nativity]"
+    Pref.Nativity 2026 12 27
+
+(* ---- RG 497: the Apostle/Evangelist natalicia list, reused from
+   {!creed_apostle_slugs} -- OUTSIDE the Nativity octave, an Apostle keeps
+   his own preface even inside another window (Sts Philip & James, 11 May,
+   inside the Paschaltide/Easter window -- the FIUV Ordo's own witness
+   this file's own [preface] header cites for RG 484(b)'s narrower
+   carve-out, checked from the other direction). ---- *)
+let test_preface_497_barnabas () = check_preface "RG 497: St Barnabas" Pref.Apostles 2026 6 11
+let test_preface_497_peter_paul () = check_preface "RG 497: Sts Peter & Paul" Pref.Apostles 2026 6 29
+let test_preface_497_philip_james_inside_easter_window () =
+  check_preface "RG 497: Sts Philip & James, inside the Easter window, still [Apostles]" Pref.Apostles 2026 5 11
+
+(* ---- RG 485(a)/(b): Epiphany itself and its own Baptism commemoration
+   (a), the wider 7-13 January window (b) -- Holy Family Sunday (11
+   January 2026) is the live witness that a temporal-origin Sunday inside
+   this window gets [Epiphany], not some Holy-Family-specific preface this
+   engine has none of. ---- *)
+let test_preface_485a_epiphany_day () = check_preface "RG 485(a): Epiphany Day" Pref.Epiphany 2026 1 6
+let test_preface_485a_baptism_commemoration () =
+  check_preface "RG 485(a): the Commemoration of the Baptism of the Lord" Pref.Epiphany 2026 1 13
+
+let test_preface_485b_holy_family_sunday () =
+  check_preface "RG 485(b): Holy Family Sunday, inside the 7-13 January window" Pref.Epiphany 2026 1 11
+
+(* ---- RG 486(a)/(b): the Lenten window, Ash Wednesday through the
+   Saturday before Passion Sunday I. ---- *)
+let test_preface_486_ash_wednesday () = check_preface "RG 486(a): Ash Wednesday" Pref.Lent 2026 2 18
+let test_preface_486_lent_saturday_boundary () =
+  check_preface "RG 486: the Saturday immediately before Passion Sunday I" Pref.Lent 2026 3 21
+
+(* ---- RG 487(a)/(b): the Passiontide window, Passion Sunday I through
+   Holy Thursday inclusive. ---- *)
+let test_preface_487_passion_sunday () = check_preface "RG 487: Passion Sunday I" Pref.Holy_cross 2026 3 22
+let test_preface_487_palm_sunday () = check_preface "RG 487: Palm Sunday" Pref.Holy_cross 2026 3 29
+let test_preface_487_holy_thursday () = check_preface "RG 487: Holy Thursday" Pref.Holy_cross 2026 4 2
+
+(* ---- RG 489(a)/(b): the Easter window, the Vigil Mass through the vigil
+   of the Ascension. ---- *)
+let test_preface_489_easter_vigil_mass () = check_preface "RG 489(a): the Easter Vigil Mass" Pref.Easter 2026 4 4
+let test_preface_489_easter_sunday () = check_preface "RG 489(a): Easter Sunday" Pref.Easter 2026 4 5
+let test_preface_489_ascension_vigil () = check_preface "RG 489(b): the vigil of the Ascension" Pref.Easter 2026 5 13
+
+(* ---- RG 490(b): the post-Ascension window. ---- *)
+let test_preface_490b_post_ascension_feria () =
+  check_preface "RG 490(b): the Friday after Ascension" Pref.Ascension 2026 5 15
+
+let test_preface_490b_sunday_after_ascension () =
+  check_preface "RG 490(b): the Sunday after Ascension" Pref.Ascension 2026 5 17
+
+(* ---- RG 493(a)/(b): the Pentecost-octave window, the vigil through the
+   following Saturday (the Ember Saturday). ---- *)
+let test_preface_493_pentecost_vigil () = check_preface "RG 493(a): the vigil of Pentecost" Pref.Holy_spirit 2026 5 23
+let test_preface_493_pentecost_sunday () = check_preface "RG 493(a): Pentecost Sunday" Pref.Holy_spirit 2026 5 24
+let test_preface_493_ember_saturday () =
+  check_preface "RG 493(a): the Ember Saturday within the Pentecost octave" Pref.Holy_spirit 2026 5 30
+
+(* ---- RG 494(b): the Trinity de-Tempore Sundays -- an Advent Sunday
+   ([temporal.season = Advent], [Class1] by construction) and an ordinary
+   Time-after-Pentecost Sunday. Both now read off [temporal]'s own season,
+   not [observed]'s rank -- see the next test for why the distinction is
+   live, not merely stylistic. ---- *)
+let test_preface_494b_advent_sunday () = check_preface "RG 494(b): Advent I Sunday" Pref.Trinity 2026 11 29
+let test_preface_494b_ordinary_class2_sunday () =
+  check_preface "RG 494(b): an ordinary Time-after-Pentecost Sunday" Pref.Trinity 2026 8 9
+
+(* ---- RG 494(b), the RG 16(a)-shaped fix round: All Saints' Day (1
+   November), [Class1], observed OUTRIGHT over the ordinary Sunday it
+   commemorates -- found via the FIUV Ordo (its own entry reads "Trinit.
+   vel de Omnibus Sanctis et Patronis", the "vel..." half an alternate
+   ORATIO reference, the SAME pattern every other "X vel Y" [praef] value
+   in that fixture already follows, never a second genuine preface). No
+   dedicated preface exists for All Saints among RG 484-497's own
+   fourteen, so RG 482's chain falls to the SUNDAY's own de-Tempore grant
+   regardless of which rank actually won the day -- exactly why this
+   branch must read [temporal]'s season, not [observed]'s [Class1] rank,
+   which an EARLIER version of [preface] wrongly required to equal
+   [Class2] and so answered [Common] here instead.
+
+   1 November 2026 is itself a Sunday (confirmed via `colitur day 2026`:
+   "all-saints class-1 white +ef-time-after-pentecost-sunday-23"), the
+   exact shape this fix concerns -- picked for that reason, not merely
+   because it is All Saints' Day. *)
+let test_preface_494b_all_saints_class1_sunday () =
+  check_preface "RG 494(b): All Saints' Day, Class1, still Trinity (no dedicated preface exists)" Pref.Trinity
+    2026 11 1
+
+(* ---- RG 498: the Common residual -- Corpus Christi is the deliberately
+   chosen witness (NOT simply "any ordinary weekday"): the 1962 Missal
+   gives it no preface of its own at all, only an OPTIONAL alternative
+   (Sacred Heart's), so it takes the plain Common, confirmed against the
+   Ordo directly (4 June 2026: "comm. vel de Cor Sacratissimo") -- a real
+   trap this engine's own tier1 list does NOT fall into (no
+   "ef-corpus-christi" entry anywhere in it). ---- *)
+let test_preface_498_corpus_christi () = check_preface "RG 498: Corpus Christi (no proper of its own)" Pref.Common 2026 6 4
+
+let test_preface_498_plain_saint () = check_preface "RG 498: a plain sanctoral saint (Lawrence)" Pref.Common 2026 8 10
+
+(* ---- Corroborating real-data invariants, task requirement 5: "every day
+   in Paschaltide should take the Easter preface unless it has a proper
+   one; every Lenten feria the Lent preface". Checked as a SWEEP, not a
+   single date, over a fixed sample span (1583-2200, matching the century+
+   spans other domain checks in this file already use) -- FAST in the
+   default suite, EXHAUSTIVE (1583-9999) gated behind
+   COLITUR_EXHAUSTIVE_SWEEP the same way {!test_exhaustive_gloria_domain_sweep}
+   above already is.
+
+   The invariant actually checked is NOT the brief's own literal phrasing
+   (which is one exception too strong, the identical "pushed back, not
+   silently special-cased" stance {!check_gloria_invariants_for_year}'s own
+   header already takes for [gloria]/432(b)): every Paschaltide-season day
+   takes [Easter], [Ascension] or [Holy_spirit] (its own three seasonal
+   windows), OR one of the season-independent title triggers this engine
+   can construct inside Paschaltide's real date range ([Bvm]/[St_joseph]/
+   [Apostles]/[Requiem]) -- but NEVER [Nativity]/[Epiphany]/[Lent]/[Trinity]/
+   [Sacred_heart]/[Christ_the_king]/[Common], none of which any real date
+   inside Paschaltide can trigger. Symmetrically for Lent: [Lent] or one of
+   [Bvm]/[St_joseph]/[Apostles]/[Requiem], never a preface belonging to a
+   date-disjoint window. Two further invariants the sweep found and kept,
+   not originally asked for but load-bearing: EVERY Christmastide-season
+   day resolves [Nativity], [Epiphany] or [Bvm] (RG 484/485 between them
+   leave no gap at all in that season on their own -- confirmed
+   exhaustively -- but RG 495's own votive-Mass half, live for the BVM
+   Saturday Office, can and does fall on a Christmastide Saturday too;
+   found live at 1584-01-07 while first running this exact sweep, kept as
+   a real witness rather than narrowed away); and Passiontide, uniquely,
+   legitimately
+   ALSO produces [Easter] exactly once a year (Holy Saturday's own Vigil
+   Mass, [n = -1] -- {!Rite_ef.Rubrics_ef.preface}'s own RG 489(a) comment;
+   this engine's day/colour model keeps that date [Passiontide] by season
+   even though the Vigil Mass's own preface has already moved to Easter's,
+   the same acknowledged per-action nuance [gloria]'s own RG 431(c) comment
+   already documents) -- asserted to be EXACTLY once per year, not merely
+   allowed, so a second, unexplained (Passiontide, Easter) day anywhere in
+   the domain still fails loudly. *)
+let check_preface_season_invariants_for_year y (counts : (int * int * int * int) ref) =
+  let days = Cal.year ctx layer y in
+  let christmastide_gaps = ref 0
+  and paschaltide_gaps = ref 0
+  and lent_gaps = ref 0
+  and passiontide_easter = ref 0 in
+  let christmastide_gaps0, paschaltide_gaps0, lent_gaps0, passiontide_easter0 = !counts in
+  christmastide_gaps := christmastide_gaps0;
+  paschaltide_gaps := paschaltide_gaps0;
+  lent_gaps := lent_gaps0;
+  passiontide_easter := passiontide_easter0;
+  Array.iter
+    (fun (d : (V.season, V.rank) LD.t) ->
+      let label = Printf.sprintf "%s (preface=%s)" (Date.to_iso8601 d.LD.date)
+          (match d.LD.preface with Some p -> Pref.to_string p | None -> "NONE")
+      in
+      (match d.LD.temporal.Temporal.season with
+      | V.Christmastide -> (
+          match d.LD.preface with
+          | Some (Pref.Nativity | Pref.Epiphany | Pref.Bvm) -> ()
+          | _ ->
+              incr christmastide_gaps;
+              Alcotest.failf "%s: Christmastide day with neither Nativity, Epiphany nor Bvm" label)
+      | V.Paschaltide -> (
+          match d.LD.preface with
+          | Some (Pref.Easter | Pref.Ascension | Pref.Holy_spirit | Pref.Bvm | Pref.St_joseph
+                 | Pref.Apostles | Pref.Requiem) ->
+              ()
+          | _ ->
+              incr paschaltide_gaps;
+              Alcotest.failf "%s: Paschaltide day with an out-of-window preface" label)
+      | V.Lent -> (
+          match d.LD.preface with
+          | Some (Pref.Lent | Pref.Bvm | Pref.St_joseph | Pref.Apostles | Pref.Requiem) -> ()
+          | _ ->
+              incr lent_gaps;
+              Alcotest.failf "%s: Lent day with an out-of-window preface" label)
+      | V.Passiontide ->
+          if d.LD.preface = Some Pref.Easter then begin
+            incr passiontide_easter;
+            let easter = Computus.gregorian_easter (Date.year d.LD.date) in
+            Alcotest.(check int)
+              (Printf.sprintf "%s: the ONLY Passiontide/Easter day is the Vigil Mass (Easter-1)" label)
+              (-1) (Date.to_rata d.LD.date - Date.to_rata easter)
+          end
+      | _ -> ()))
+    days;
+  counts := (!christmastide_gaps, !paschaltide_gaps, !lent_gaps, !passiontide_easter)
+
+let test_preface_season_invariants_sample () =
+  let counts = ref (0, 0, 0, 0) in
+  for y = 1583 to 1782 do
+    check_preface_season_invariants_for_year y counts
+  done;
+  let _, _, _, passiontide_easter = !counts in
+  Alcotest.(check bool) "the 200-year sample found the once-a-year Passiontide/Easter exception" true
+    (passiontide_easter >= 200)
+
+let test_exhaustive_preface_season_domain_sweep () =
+  if Sys.getenv_opt colitur_exhaustive_sweep_env = None then Alcotest.skip ()
+  else begin
+    let counts = ref (0, 0, 0, 0) in
+    for y = 1583 to 9999 do
+      check_preface_season_invariants_for_year y counts
+    done;
+    let christmastide_gaps, paschaltide_gaps, lent_gaps, passiontide_easter = !counts in
+    Printf.printf
+      "preface season sweep 1583..9999: christmastide_gaps=%d paschaltide_gaps=%d lent_gaps=%d \
+       passiontide_easter=%d\n%!"
+      christmastide_gaps paschaltide_gaps lent_gaps passiontide_easter;
+    Alcotest.(check int) "zero Christmastide gaps anywhere in the domain" 0 christmastide_gaps;
+    Alcotest.(check int) "zero Paschaltide out-of-window prefaces anywhere in the domain" 0 paschaltide_gaps;
+    Alcotest.(check int) "zero Lent out-of-window prefaces anywhere in the domain" 0 lent_gaps;
+    (* 8416, not 8417 (the domain's own year count): a genuine, pre-existing
+       DOMAIN-BOUNDARY edge, not a preface defect -- {!Cal.year}'s own
+       liturgical year "opening in civil year 9999" cannot construct any
+       date past 1583-9999 ({!Date.make}'s own validated range), so it
+       returns only 34 days (28 November-31 December), never reaching its
+       own Easter/Holy Saturday (which would fall in year 10000). Found by
+       running this exact sweep: it returned 8416 first, not asserted
+       blindly at 8417 -- checked directly ([Cal.year ctx layer 9999]
+       alone, printed length 34) before writing this comment, the same
+       "measure before adjudicating" discipline every allow-list in this
+       project follows. The identical edge is why
+       docs/research/rules-register.md's own Layer.index citation already
+       reads "both edges, 1582 and 10000, bit during development" --
+       this sweep is a second witness to the same known boundary, not a
+       new one. *)
+    Alcotest.(check int) "one Passiontide/Easter day per year, every year but the domain's own last" 8416
+      passiontide_easter
+  end
+
 (* ---- ITEM 1: RG 111(a), the sung-Mass commemoration cap
    ({!Colitur_kernel.Precedence.sung_mass_commemorations}) -- two real
    calendar days, one of each shape, resolved through the identical
@@ -855,4 +1182,62 @@ let suite =
       Alcotest.test_case "RG 111(a): an ordinary-only Low-Mass set is empty at Sung Mass" `Quick
         test_rg111a_ordinary_only_dropped;
       Alcotest.test_case "RG 111(a): a privileged commemoration survives at Sung Mass" `Quick
-        test_rg111a_privileged_kept ] )
+        test_rg111a_privileged_kept;
+      Alcotest.test_case "preface: Good Friday, no Mass" `Quick test_preface_good_friday_no_mass;
+      Alcotest.test_case "RG 499: All Souls' Day (transferred)" `Quick test_preface_499_all_souls;
+      Alcotest.test_case "RG 487(a): the Exaltation of the Holy Cross" `Quick test_preface_487a_exaltation;
+      Alcotest.test_case "RG 487(a): the Most Precious Blood" `Quick test_preface_487a_precious_blood;
+      Alcotest.test_case "RG 491: the Sacred Heart" `Quick test_preface_491_sacred_heart;
+      Alcotest.test_case "RG 492: Christ the King" `Quick test_preface_492_christ_the_king;
+      Alcotest.test_case "RG 490(a): Ascension Day" `Quick test_preface_490a_ascension_day;
+      Alcotest.test_case "RG 494(a): Trinity Sunday" `Quick test_preface_494a_trinity_sunday;
+      Alcotest.test_case "RG 496: St Joseph, Spouse of the BVM" `Quick test_preface_496_joseph_spouse;
+      Alcotest.test_case "RG 496: St Joseph the Workman" `Quick test_preface_496_joseph_workman;
+      Alcotest.test_case "RG 495: the Assumption (marian_slugs)" `Quick test_preface_495_assumption;
+      Alcotest.test_case "RG 495: the BVM Saturday Office (subject=Bvm)" `Quick
+        test_preface_495_bvm_saturday_office;
+      Alcotest.test_case "RG 484(a): the Purification" `Quick test_preface_484a_purification;
+      Alcotest.test_case "RG 484(a): Christmas Day itself" `Quick test_preface_484_nativity_day;
+      Alcotest.test_case "RG 484(b): St Stephen, inside the Nativity octave" `Quick
+        test_preface_484_stephen_in_octave;
+      Alcotest.test_case "RG 484(a): 1 January, the Octave Day" `Quick test_preface_484_jan1_octave_day;
+      Alcotest.test_case "RG 484(b): 3 January, the extra de-Tempore days" `Quick test_preface_484b_jan2to5;
+      Alcotest.test_case "RG 484(b): St John the Evangelist, inside the Nativity octave" `Quick
+        test_preface_484b_overrides_apostle_in_octave;
+      Alcotest.test_case "RG 497: St Barnabas" `Quick test_preface_497_barnabas;
+      Alcotest.test_case "RG 497: Sts Peter & Paul" `Quick test_preface_497_peter_paul;
+      Alcotest.test_case "RG 497: Sts Philip & James, inside the Easter window" `Quick
+        test_preface_497_philip_james_inside_easter_window;
+      Alcotest.test_case "RG 485(a): Epiphany Day" `Quick test_preface_485a_epiphany_day;
+      Alcotest.test_case "RG 485(a): the Commemoration of the Baptism of the Lord" `Quick
+        test_preface_485a_baptism_commemoration;
+      Alcotest.test_case "RG 485(b): Holy Family Sunday, inside the 7-13 January window" `Quick
+        test_preface_485b_holy_family_sunday;
+      Alcotest.test_case "RG 486(a): Ash Wednesday" `Quick test_preface_486_ash_wednesday;
+      Alcotest.test_case "RG 486: the Saturday before Passion Sunday I" `Quick
+        test_preface_486_lent_saturday_boundary;
+      Alcotest.test_case "RG 487: Passion Sunday I" `Quick test_preface_487_passion_sunday;
+      Alcotest.test_case "RG 487: Palm Sunday" `Quick test_preface_487_palm_sunday;
+      Alcotest.test_case "RG 487: Holy Thursday" `Quick test_preface_487_holy_thursday;
+      Alcotest.test_case "RG 489(a): the Easter Vigil Mass" `Quick test_preface_489_easter_vigil_mass;
+      Alcotest.test_case "RG 489(a): Easter Sunday" `Quick test_preface_489_easter_sunday;
+      Alcotest.test_case "RG 489(b): the vigil of the Ascension" `Quick test_preface_489_ascension_vigil;
+      Alcotest.test_case "RG 490(b): the Friday after Ascension" `Quick test_preface_490b_post_ascension_feria;
+      Alcotest.test_case "RG 490(b): the Sunday after Ascension" `Quick
+        test_preface_490b_sunday_after_ascension;
+      Alcotest.test_case "RG 493(a): the vigil of Pentecost" `Quick test_preface_493_pentecost_vigil;
+      Alcotest.test_case "RG 493(a): Pentecost Sunday" `Quick test_preface_493_pentecost_sunday;
+      Alcotest.test_case "RG 493(a): the Ember Saturday within the Pentecost octave" `Quick
+        test_preface_493_ember_saturday;
+      Alcotest.test_case "RG 494(b): Advent I Sunday" `Quick test_preface_494b_advent_sunday;
+      Alcotest.test_case "RG 494(b): an ordinary Time-after-Pentecost Sunday" `Quick
+        test_preface_494b_ordinary_class2_sunday;
+      Alcotest.test_case "RG 494(b): All Saints' Day, Class1, still Trinity" `Quick
+        test_preface_494b_all_saints_class1_sunday;
+      Alcotest.test_case "RG 498: Corpus Christi (no proper of its own)" `Quick test_preface_498_corpus_christi;
+      Alcotest.test_case "RG 498: a plain sanctoral saint (Lawrence)" `Quick test_preface_498_plain_saint;
+      Alcotest.test_case "preface domain sanity: Christmastide/Paschaltide/Lent window invariants (sample)"
+        `Quick test_preface_season_invariants_sample;
+      Alcotest.test_case
+        "preface domain sweep 1583..9999: window invariants, committed not sampled" `Slow
+        test_exhaustive_preface_season_domain_sweep ] )