1 files changed, 70 insertions, 24 deletions

diff --git a/test/test_citation_coverage.ml b/test/test_citation_coverage.ml
index 31d49eb..a131d50 100644
--- a/test/test_citation_coverage.ml
+++ b/test/test_citation_coverage.ml
@@ -6,33 +6,78 @@
 
    Same shape as test_lang_coverage.ml, which this file deliberately mirrors:
    a miss there is a slug with no name, a miss here is a citation the parser
-   cannot read. *)
+   cannot read.
+
+   The walk below also drives the round-trip check (Sigla facade, Task 5):
+   ONE pass over 1970-2070 collects into TWO tables, [bad_parse] and
+   [bad_round_trip], rather than walking the whole range twice for two
+   independent Alcotest cases -- measured, a second walk would cost ~1.5s of
+   a 5.65s fast suite for zero extra coverage. *)
 
 module P = Colitur_citation.Parse
 
+let bad_parse : (string, string) Hashtbl.t = Hashtbl.create 64
+let bad_round_trip : (string, string) Hashtbl.t = Hashtbl.create 16
+let walked = ref false
+
+(* Parse -> render -> parse must reach the same structure.
+
+   NOTE the [names] function: [Book.default_spelling], NOT [Book.to_string].
+   [to_string] returns the internal id ("corinthians_1"), which is not a
+   registered token, so rendering with it produces something Parse cannot
+   read back -- 0 of 738 round-trip. Measured during Task 4; do not
+   "simplify" this back to to_string. A renderer that emits an unparseable
+   string, or a style whose own output it cannot read, fails here. Compares
+   STRUCTURE, not text: the rendered form legitimately differs from the
+   input (a normalised book spelling, a dropped trailing period), and
+   asserting text equality would just pin those differences. *)
+let sg =
+  Colitur_citation.Sigla.make ~style:Colitur_citation.Render.default_style
+    ~tradition:Colitur_citation.Book.vulgate
+    ~names:(fun id _form -> Colitur_citation.Book.default_spelling id)
+
+let walk () =
+  if not !walked then begin
+    walked := true;
+    let layer =
+      match Test_support.load_ef_layer () with
+      | Ok l -> l
+      | Error e -> Alcotest.failf "%s" e
+    in
+    let ctx = Test_support.ef_context () in
+    for y = 1970 to 2070 do
+      Array.iter
+        (fun (d : (Rite_ef.Vocab_ef.season, Rite_ef.Vocab_ef.rank) Colitur_kernel.Liturgical_day.t) ->
+          List.iter
+            (fun (c : Colitur_kernel.Citation.t) ->
+              let r = c.Colitur_kernel.Citation.reference in
+              match P.parse r with
+              | Error e -> if not (Hashtbl.mem bad_parse r) then Hashtbl.add bad_parse r e
+              | Ok first ->
+                  let rendered = Colitur_citation.Sigla.format sg r in
+                  (match P.parse rendered with
+                   | Error e ->
+                       Hashtbl.replace bad_round_trip r ("re-parse failed: " ^ e)
+                   | Ok again ->
+                       if again <> first then
+                         Hashtbl.replace bad_round_trip r ("structure changed: " ^ rendered)))
+            d.Colitur_kernel.Liturgical_day.citations)
+        (Colitur_kernel.Calendar.year ctx layer y)
+    done
+  end
+
 let test_every_citation_parses () =
-  let layer =
-    match Test_support.load_ef_layer () with
-    | Ok l -> l
-    | Error e -> Alcotest.failf "%s" e
-  in
-  let ctx = Test_support.ef_context () in
-  let bad = Hashtbl.create 64 in
-  for y = 1970 to 2070 do
-    Array.iter
-      (fun (d : (Rite_ef.Vocab_ef.season, Rite_ef.Vocab_ef.rank) Colitur_kernel.Liturgical_day.t) ->
-        List.iter
-          (fun (c : Colitur_kernel.Citation.t) ->
-            let r = c.Colitur_kernel.Citation.reference in
-            match P.parse r with
-            | Ok _ -> ()
-            | Error e -> if not (Hashtbl.mem bad r) then Hashtbl.add bad r e)
-          d.Colitur_kernel.Liturgical_day.citations)
-      (Colitur_kernel.Calendar.year ctx layer y)
-  done;
-  if Hashtbl.length bad > 0 then begin
-    Hashtbl.iter (fun r e -> Printf.eprintf "UNPARSED %S: %s\n" r e) bad;
-    Alcotest.failf "%d citation(s) did not parse" (Hashtbl.length bad)
+  walk ();
+  if Hashtbl.length bad_parse > 0 then begin
+    Hashtbl.iter (fun r e -> Printf.eprintf "UNPARSED %S: %s\n" r e) bad_parse;
+    Alcotest.failf "%d citation(s) did not parse" (Hashtbl.length bad_parse)
+  end
+
+let test_round_trip () =
+  walk ();
+  if Hashtbl.length bad_round_trip > 0 then begin
+    Hashtbl.iter (fun r e -> Printf.eprintf "ROUND-TRIP %S: %s\n" r e) bad_round_trip;
+    Alcotest.failf "%d citation(s) failed round-trip" (Hashtbl.length bad_round_trip)
   end
 
 (* This project has ONE test executable. Every test_<module>.ml exposes a
@@ -40,4 +85,5 @@ let test_every_citation_parses () =
    Alcotest.run here. Marked `Slow like test_lang_coverage's own year walk. *)
 let suite =
   ( "citation-coverage",
-    [ Alcotest.test_case "every citation parses" `Slow test_every_citation_parses ] )
+    [ Alcotest.test_case "every citation parses" `Slow test_every_citation_parses;
+      Alcotest.test_case "sigla round-trip" `Slow test_round_trip ] )