fix: audit findings — parser strictness, name ambiguity, and errors

Found by auditing the shipped program rather than the diff.

The parser accepted OCaml integer-literal syntax, so "Luke 1_1:5" read as
chapter ELEVEN and "+5" as 5 -- a typo silently becoming a different
chapter, reachable through any user overlay. Numbers are now plain digits
and positive, and a descending range is rejected: 1:20-10 is always a
transcription error. No shipped citation changed.

FOUR PAIRS OF DIFFERENT BOOKS SHARED A FULL TITLE. 1 and 2 Corinthians
both rendered "Epistola ad Corinthios", as did Thessalonians, Timothy and
Peter -- 108 citations in 2027 alone that a reader cannot resolve to a
book. This is the Kings defect fixed earlier and not generalised. The
titles now carry their volume numeral, marked CONSTRUCTED, and a test
asserts no two books share a name -- while allowing the case where two
ids ARE the same book under different numbering, which a tradition
relates.

Spec section 8.5 is now delivered rather than merely recorded. Shipped
styles did not re-parse their own output: 32 of 52 Latin abbreviations
and 49 of 52 full titles failed, so a citation copied from colitur's own
output into an overlay was passed through untouched and printed in the
wrong language, silently. Every shipped name is registered as a spelling
and split_book learned multi-word titles by longest-token match. Now 0
of 52 fail beyond the same-book aliases.

Overlay errors were written for a compiler author: they named an OCaml
source file the reader does not have and buried the useful token. The
existing five-path rewriter is replaced by a generic one, applied to
every load path rather than one, so "rank: is not one of the allowed
values (at Class9)" replaces the raw Of_sexp_error dump.

Also: the new-overlay scaffold documented citations and layer without
showing them, and its comment implied the wrong nesting -- the single
easiest thing to get wrong; error messages echoed whole file lines,
copying an unrelated file's contents into stderr when a flag pointed at
one; and config --show validated partway down its table, exiting 2 after
writing five rows to stdout.

1 files changed, 3 insertions, 19 deletions

diff --git a/lib/kernel/overlay.ml b/lib/kernel/overlay.ml
index 58d8847..516379d 100644
--- a/lib/kernel/overlay.ml
+++ b/lib/kernel/overlay.ml
@@ -132,23 +132,6 @@ let fill_defaults ~id sexp =
    actually reach a user into the vocabulary of the file they are looking at.
    Anything unrecognised passes through verbatim rather than being reworded
    into something possibly wrong. *)
-let humanise_error msg =
-  let replace ~sub ~by s =
-    let n = String.length sub and len = String.length s in
-    let rec go i acc =
-      if i > len - n then acc ^ String.sub s i (len - i)
-      else if String.equal (String.sub s i n) sub then go (i + n) (acc ^ by)
-      else go (i + 1) (acc ^ String.make 1 s.[i])
-    in
-    if n = 0 then s else go 0 ""
-  in
-  msg
-  |> replace ~sub:"lib/kernel/celebration.ml.t_of_sexp" ~by:"celebration"
-  |> replace ~sub:"lib/kernel/colour.ml.t_of_sexp" ~by:"colour"
-  |> replace ~sub:"lib/kernel/subject.ml.t_of_sexp" ~by:"subject"
-  |> replace ~sub:"lib/kernel/date_spec.ml.t_of_sexp" ~by:"date"
-  |> replace ~sub:"lib/kernel/overlay.ml.directive_of_sexp" ~by:"directive"
-
 let load rank_of_sexp path =
   match Sexplib.Sexp.load_sexp path with
   | exception Sys_error msg -> Error msg
@@ -157,7 +140,8 @@ let load rank_of_sexp path =
      [Sexplib.Sexp.Parse_error], so a catch-all here -- placed last among the
      exception branches -- is what actually keeps every parse failure inside
      [Error] instead of escaping. *)
-  | exception exn -> Error (Printf.sprintf "%s: %s" path (Printexc.to_string exn))
+  | exception exn ->
+      Error (Printf.sprintf "%s: %s" path (Sexp_error.humanise (Printexc.to_string exn)))
   | sexp -> (
       (* The overlay's own [id] is needed to default [layer], so read it off
          the raw sexp first. If it is missing or malformed the derived parser
@@ -174,4 +158,4 @@ let load rank_of_sexp path =
       match t_of_sexp rank_of_sexp (fill_defaults ~id sexp) with
       | t -> Ok t
       | exception exn ->
-          Error (Printf.sprintf "%s: %s" path (humanise_error (Printexc.to_string exn))))
+          Error (Printf.sprintf "%s: %s" path (Sexp_error.humanise (Printexc.to_string exn))))