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bynk_syntax/
diagnostics.rs

1//! Central registry of diagnostic codes.
2//!
3//! This is the single source of truth for the `bynk.*` codes the compiler can
4//! emit. The reference page `site/src/content/docs/book/reference/diagnostics.md` is generated
5//! from [`render_markdown`], and the test `tests/diagnostics_registry.rs`
6//! asserts that this table matches exactly the set of codes used across the
7//! compiler source — so a new code cannot be introduced without documenting it
8//! here, and a removed code cannot linger in the docs.
9//!
10//! Each entry is a `(code, summary)` pair, optionally tagged with the grammar
11//! production(s) it constrains (`grammar_symbol`). The category shown in the
12//! generated reference is derived from the second dotted segment of the code;
13//! the grammar weave (`docs/grammar-semantics.json`, the
14//! `{{#grammar-semantics}}` directive, and the diagnostics page's Construct
15//! column) is generated from `grammar_symbol`.
16
17/// One documented diagnostic: its stable code and a one-line summary of the
18/// cause. Richer "cause and fix" material for the common diagnostics lives in
19/// the troubleshooting how-to guides.
20pub struct DiagnosticInfo {
21    pub code: &'static str,
22    pub summary: &'static str,
23    /// The grammar production(s) this diagnostic constrains, by `tree-sitter`
24    /// rule name (e.g. `http_handler`). This is the single source of the
25    /// "static semantics" weave: a grammar-reference entry embeds the
26    /// diagnostics for a rule via `{{#grammar-semantics <rule>}}`, generated
27    /// from here. Empty for diagnostics with no single governing construct
28    /// (e.g. `bynk.boundary.structural_mismatch`). Every non-empty name is
29    /// checked against the grammar by `tests/diagnostics_registry.rs`.
30    pub grammar_symbol: &'static [&'static str],
31}
32
33/// Every diagnostic code the compiler emits, sorted by code.
34pub const REGISTRY: &[DiagnosticInfo] = &[
35    d(
36        "bynk.actor.bearer_identity_not_string_constructible",
37        "A `Bearer` actor's identity is not a string-constructible type.",
38    ),
39    d(
40        "bynk.actor.bearer_missing_secret",
41        "A `Bearer` actor does not name its signing secret.",
42    ),
43    d(
44        "bynk.actor.binder_shadows_param",
45        "A `by` actor binder collides with a handler parameter of the same name.",
46    ),
47    d(
48        "bynk.actor.by_on_agent",
49        "A `by` actor clause was placed on an agent `on call` handler, which has no actor.",
50    ),
51    d(
52        "bynk.actor.duplicate_sum_scheme",
53        "Two peers in a multi-actor sum share an authentication scheme.",
54    ),
55    d(
56        "bynk.actor.identity_not_sealed",
57        "An actor identity type is not a context-ownable (sealed) value type.",
58    ),
59    d(
60        "bynk.actor.missing_by_on_http",
61        "An HTTP handler lacks the required `by` actor clause.",
62    ),
63    d(
64        "bynk.actor.outside_context",
65        "An `actor` was declared outside a context (e.g. in a commons).",
66    ),
67    d(
68        "bynk.actor.refinement_base_unsupported",
69        "A refinement actor's base is not a `Bearer` actor (no claims to authorise against).",
70    ),
71    d(
72        "bynk.actor.refinement_in_sum",
73        "A refinement actor appears as a member of a multi-actor sum.",
74    ),
75    d(
76        "bynk.actor.refinement_predicate_unsupported",
77        "A refinement actor's `where` predicate is outside the closed claim-predicate set.",
78    ),
79    d(
80        "bynk.actor.scheme_not_admissible",
81        "An actor's scheme is not admissible on this handler's protocol.",
82    ),
83    d(
84        "bynk.actor.signature_identity_unsupported",
85        "A `Signature` actor declared an `identity`, which is not yet supported.",
86    ),
87    d(
88        "bynk.actor.signature_missing_header",
89        "A `Signature` actor does not name its signature header.",
90    ),
91    d(
92        "bynk.actor.signature_missing_secret",
93        "A `Signature` actor does not name its signing secret.",
94    ),
95    d(
96        "bynk.actor.signature_requires_body",
97        "A `Signature` handler does not take a `body` parameter.",
98    ),
99    d(
100        "bynk.actor.signature_tolerance_without_timestamp",
101        "A `Signature` actor set `tolerance` without a `timestamp` header.",
102    ),
103    d(
104        "bynk.actor.sum_requires_binder",
105        "A multi-actor sum `by` clause has no binder to match the resolved actor.",
106    ),
107    d(
108        "bynk.actor.unknown_actor",
109        "A handler's `by` clause names an actor that is not declared.",
110    ),
111    d(
112        "bynk.actor.unknown_scheme",
113        "An actor declares an authentication scheme that is not compiler-known.",
114    ),
115    d(
116        "bynk.actor.unreachable_sum_arm",
117        "A multi-actor sum has an arm unreachable after a catch-all (`None`) peer.",
118    ),
119    dg(
120        "bynk.adapter.consumes_context",
121        "An `adapter` consumed a context; adapter dependencies are adapter-to-adapter.",
122        &["consumes_decl"],
123    ),
124    dg(
125        "bynk.adapter.consumes_requires_selection",
126        "An `adapter` used a whole-unit or aliased `consumes`; adapters must select capabilities with `consumes U { Cap, … }`.",
127        &["consumes_decl"],
128    ),
129    dg(
130        "bynk.adapter.disallowed_item",
131        "An `adapter` declared a `service`, `agent`, or other item it may not contain.",
132        &["adapter_decl"],
133    ),
134    dg(
135        "bynk.adapter.duplicate_binding",
136        "An `adapter` declared more than one `binding` clause.",
137        &["binding_decl"],
138    ),
139    dg(
140        "bynk.adapter.no_binding",
141        "An `adapter` declares an external provider but no `binding` module to supply it.",
142        &["adapter_decl"],
143    ),
144    dg(
145        "bynk.adapter.provider_has_body",
146        "A provider inside an `adapter` has a Bynk body; adapter providers must be external.",
147        &["provider_decl"],
148    ),
149    dg(
150        "bynk.agent.construction_arity",
151        "An agent was constructed with the wrong number of key arguments.",
152        &["agent_decl"],
153    ),
154    dg(
155        "bynk.agent.handler_arity",
156        "An agent handler was called with the wrong number of arguments.",
157        &["agent_decl"],
158    ),
159    dg(
160        "bynk.agent.handler_not_found",
161        "Called a handler the agent does not declare.",
162        &["agent_decl"],
163    ),
164    dg(
165        "bynk.agent.key_mismatch",
166        "An agent key argument has the wrong type.",
167        &["agent_decl"],
168    ),
169    dg(
170        "bynk.agent.outside_context",
171        "An `agent` was declared outside a context.",
172        &["agent_decl"],
173    ),
174    dg(
175        "bynk.agent.return_not_effect",
176        "An agent handler's return type is not an `Effect`.",
177        &["agent_decl"],
178    ),
179    dg(
180        "bynk.agents.bad_state_initialiser",
181        "An agent `store` field initialiser is not a static value of the field's type.",
182        &["store_field"],
183    ),
184    dg(
185        "bynk.agents.non_zeroable_state_field",
186        "An agent `store` field has no initialiser and no implicit zero value.",
187        &["store_field"],
188    ),
189    d(
190        "bynk.boundary.structural_mismatch",
191        "Data crossing a context boundary did not match the expected shape.",
192    ),
193    dg(
194        "bynk.capability.op_arity",
195        "A capability operation was called with the wrong number of arguments.",
196        &["capability_decl"],
197    ),
198    dg(
199        "bynk.capability.outside_context",
200        "A `capability` was declared outside a context.",
201        &["capability_decl"],
202    ),
203    dg(
204        "bynk.capability.unknown_operation",
205        "Referenced an operation the capability does not declare.",
206        &["capability_decl"],
207    ),
208    d(
209        "bynk.cell.invalid_target",
210        "A `:=` write targets something that is not a `store Cell` field.",
211    ),
212    d(
213        "bynk.cell.self_reference",
214        "A `:=` right-hand side reads the cell being written (a read-modify-write); use `.update`.",
215    ),
216    dg(
217        "bynk.consumes.alias_conflict",
218        "Two `consumes` aliases collide.",
219        &["consumes_decl"],
220    ),
221    dg(
222        "bynk.consumes.capability_name_clash",
223        "Two flattened `consumes U { Cap }` capabilities collide, or one clashes with a local capability.",
224        &["consumes_decl"],
225    ),
226    dg(
227        "bynk.consumes.in_commons",
228        "`consumes` appears in a `commons` (it is only valid in a context).",
229        &["consumes_decl"],
230    ),
231    dg(
232        "bynk.consumes.name_conflict",
233        "A `consumes` name collides with another name in scope.",
234        &["consumes_decl"],
235    ),
236    dg(
237        "bynk.consumes.self_reference",
238        "A context `consumes` itself.",
239        &["consumes_decl"],
240    ),
241    dg(
242        "bynk.consumes.service_arity",
243        "A consumed service was called with the wrong number of arguments.",
244        &["consumes_decl"],
245    ),
246    dg(
247        "bynk.consumes.target_is_commons",
248        "`consumes` targets a `commons` instead of a context.",
249        &["consumes_decl"],
250    ),
251    dg(
252        "bynk.consumes.unknown_context",
253        "`consumes` names a context that does not exist.",
254        &["consumes_decl"],
255    ),
256    dg(
257        "bynk.consumes.unknown_service",
258        "Called a service the consumed context does not declare.",
259        &["consumes_decl"],
260    ),
261    d(
262        "bynk.context.consumes_cycle",
263        "Contexts form a `consumes` dependency cycle.",
264    ),
265    d(
266        "bynk.context.external_construction",
267        "A context-owned type was constructed from outside that context.",
268    ),
269    dg(
270        "bynk.context.external_provider",
271        "A bodiless (external) provider was declared outside an `adapter`.",
272        &["provider_decl"],
273    ),
274    d(
275        "bynk.context.opaque_inspection",
276        "An opaquely-exported type was inspected from outside its context.",
277    ),
278    d(
279        "bynk.contract.duplicate_name",
280        "A function declares two contract clauses (`requires`/`ensures`) with the same name.",
281    ),
282    d(
283        "bynk.contract.impure_predicate",
284        "A contract predicate uses an effectful or test-only construct; a contract clause must be pure.",
285    ),
286    d(
287        "bynk.contract.not_bool",
288        "A contract predicate does not have type `Bool`.",
289    ),
290    d(
291        "bynk.contract.restated_by_test",
292        "A `case`/`property` merely restates a contract clause already declared at the function; the test is redundant.",
293    ),
294    d(
295        "bynk.contract.result_in_requires",
296        "A precondition (`requires`) references `result`; the return value is only in scope inside an `ensures`.",
297    ),
298    dg(
299        "bynk.cron.bad_params",
300        "A cron handler declares more than one parameter, or a non-`Int` one.",
301        &["cron_handler"],
302    ),
303    dg(
304        "bynk.cron.duplicate_schedule",
305        "Two cron handlers declare the same schedule.",
306        &["cron_handler"],
307    ),
308    dg(
309        "bynk.cron.invalid_schedule",
310        "A cron expression is not five whitespace-separated fields.",
311        &["cron_handler"],
312    ),
313    dg(
314        "bynk.cron.return_not_effect_result",
315        "A cron handler does not return `Effect[Result[(), E]]`.",
316        &["cron_handler"],
317    ),
318    d(
319        "bynk.duration.literal_overflow",
320        "A `Duration` literal (`<int>.<unit>`) exceeds the representable millisecond range.",
321    ),
322    dg(
323        "bynk.effect.bind_in_pure_context",
324        "An `<-` bind was used in a pure (non-effectful) context.",
325        &["effect_let_stmt"],
326    ),
327    dg(
328        "bynk.effect.bind_on_non_effect",
329        "An `<-` bind was applied to a non-`Effect` value.",
330        &["effect_let_stmt"],
331    ),
332    d(
333        "bynk.effect.capability_in_pure_context",
334        "A capability was used in a pure context.",
335    ),
336    d(
337        "bynk.effect.cross_context_in_pure_context",
338        "A cross-context call was made in a pure context.",
339    ),
340    dg(
341        "bynk.effect.fn_value_in_pure_context",
342        "An effectful function value was called in a pure context; like a capability call, it is legal only where the enclosing body is effectful.",
343        &["call"],
344    ),
345    dg(
346        "bynk.expect.not_bool",
347        "`expect` was given a non-`Bool` predicate.",
348        &["expect_expr"],
349    ),
350    dg(
351        "bynk.expect.outside_case",
352        "`expect` was used outside a `case` body.",
353        &["expect_expr"],
354    ),
355    dg(
356        "bynk.exports.capability_not_provided",
357        "An exported capability has no provider in its context.",
358        &["exports_decl"],
359    ),
360    dg(
361        "bynk.exports.conflicting_visibility",
362        "A type is exported with conflicting visibilities.",
363        &["exports_decl"],
364    ),
365    dg(
366        "bynk.exports.duplicate_export",
367        "The same name is exported more than once.",
368        &["exports_decl"],
369    ),
370    dg(
371        "bynk.exports.duplicate_in_clause",
372        "A name appears twice in one `exports` clause.",
373        &["exports_decl"],
374    ),
375    dg(
376        "bynk.exports.undeclared_capability",
377        "`exports capability` names a capability that is not declared.",
378        &["exports_decl"],
379    ),
380    dg(
381        "bynk.exports.undeclared_type",
382        "`exports` names a type that is not declared.",
383        &["exports_decl"],
384    ),
385    dg(
386        "bynk.generics.no_bounds",
387        "A type parameter carries a bound (`[A: …]`); bounded generics are not in v0.20a.",
388        &["fn_decl"],
389    ),
390    dg(
391        "bynk.generics.no_generic_types",
392        "A `type` declaration carries a type-parameter list; generic type declarations are not in v0.20a (type parameters belong to functions).",
393        &["type_decl"],
394    ),
395    dg(
396        "bynk.generics.type_arg_mismatch",
397        "Inferred or explicit type arguments conflict, have the wrong arity, target a non-generic function, or a type parameter shadows a declared type.",
398        &["call"],
399    ),
400    dg(
401        "bynk.generics.uninferable_type_arg",
402        "A generic function's type parameter could not be inferred from the arguments and was not given explicitly (`name[T](…)`); a bare generic function also cannot be passed as a value in v0.20a.",
403        &["call"],
404    ),
405    dg(
406        "bynk.given.cross_context_unknown_capability",
407        "`given B.Cap` names a capability the consumed context does not export.",
408        &["given_clause"],
409    ),
410    dg(
411        "bynk.given.undeclared_capability",
412        "A handler uses a capability it did not declare with `given`.",
413        &["given_clause"],
414    ),
415    dg(
416        "bynk.given.unknown_capability",
417        "`given` names a capability that does not exist.",
418        &["given_clause"],
419    ),
420    dg(
421        "bynk.given.unused_capability",
422        "A `given` capability is never used (warning).",
423        &["given_clause"],
424    ),
425    d(
426        "bynk.held.branch_divergence",
427        "Branches of a conditional leave a held value (e.g. `Connection[F]`) in inconsistent ownership states — one consumes or stores it, another leaves it owned (§2.9.5, real-time track slice 2).",
428    ),
429    d(
430        "bynk.held.consume_on_borrow",
431        "A consuming operation (`close`/`put`/`take`) is called on a *borrowed* held reference — borrows admit only non-consuming operations like `send` (§2.9.3, real-time track slice 2).",
432    ),
433    d(
434        "bynk.held.leak",
435        "A held value (`Connection[F]`) is still owned at scope exit — it must be disposed (stored, closed, or transferred) before the handler returns (§2.9.1, real-time track slice 2).",
436    ),
437    d(
438        "bynk.held.unsupported_map_op",
439        "A held `Map[K, Connection]` is given an `update`/`upsert` — a held resource cannot be transformed by a `(Connection) -> Connection` function; use `put`/`get`/`remove` (real-time track slice 3b-ii).",
440    ),
441    d(
442        "bynk.held.unsupported_storage",
443        "A held value (`Connection[F]`) is stored in a `Set`/`Log`/`Cache` — held values may only live in `Cell[Option[Connection]]` or `Map[K, Connection]` (§2.9.3, real-time track slice 2).",
444    ),
445    d(
446        "bynk.held.use_after_consume",
447        "A held value (`Connection[F]`) is used after a consuming operation (`close`/`put`/`take`) ended its lifetime (§2.9.2, real-time track slice 2).",
448    ),
449    d(
450        "bynk.history.not_an_agent",
451        "A `for all run: History[T]` names a `T` that is not an agent — only an agent has handlers to sequence and reachable states to observe (testing track slice 7, ADR 0155).",
452    ),
453    d(
454        "bynk.history.not_generable",
455        "A `for all run: History[Agent]` targets an agent with a handler parameter whose type cannot be generated (e.g. a `Matches` refinement), so its call-history cannot be driven (testing track slice 7, ADR 0155).",
456    ),
457    d(
458        "bynk.history.outside_property",
459        "`History[Agent]` appears outside a `property`'s `for all` binding — it is a test-only generator, not a value type (testing track slice 7, ADR 0155).",
460    ),
461    d(
462        "bynk.history.restates_invariant",
463        "A history property merely re-checks a guarantee a declared `invariant`/`transition` already enforces on every reached state (testing track slice 7, ADR 0155).",
464    ),
465    dg(
466        "bynk.http.body_on_get_or_delete",
467        "A GET or DELETE handler declares a `body` parameter.",
468        &["http_handler"],
469    ),
470    d(
471        "bynk.http.cache_bad_max_age",
472        "A `@cache` annotation's `maxAge` is missing or not a positive `Duration` literal.",
473    ),
474    d(
475        "bynk.http.cache_bad_scope",
476        "A `@cache` annotation's `scope` is not `public` or `private`.",
477    ),
478    d(
479        "bynk.http.cache_duplicate",
480        "A handler carries more than one `@cache` annotation.",
481    ),
482    d(
483        "bynk.http.cache_on_non_get",
484        "A `@cache` annotation is placed on a handler that is not `on http GET`.",
485    ),
486    d(
487        "bynk.http.cache_unknown_arg",
488        "A `@cache` annotation has an argument outside the closed set (`maxAge`/`scope`).",
489    ),
490    d(
491        "bynk.http.cors_invalid_field",
492        "A `cors` policy field (`headers`/`credentials`/`maxAge`) has the wrong value shape.",
493    ),
494    d(
495        "bynk.http.cors_invalid_origins",
496        "A `cors` policy's `origins` is missing, empty, or not a list of string literals.",
497    ),
498    d(
499        "bynk.http.cors_not_http",
500        "A `cors { }` policy appears on a service that is not `from http`.",
501    ),
502    d(
503        "bynk.http.cors_unknown_field",
504        "A `cors { }` policy declares a field outside the closed set.",
505    ),
506    d(
507        "bynk.http.cors_wildcard_credentials",
508        "A `cors` policy combines `credentials: true` with the wildcard origin `[\"*\"]`.",
509    ),
510    dg(
511        "bynk.http.duplicate_route",
512        "Two handlers share the same method and route.",
513        &["http_handler"],
514    ),
515    dg(
516        "bynk.http.extra_param",
517        "A handler parameter is neither a path parameter nor `body`.",
518        &["http_handler"],
519    ),
520    dg(
521        "bynk.http.invalid_path",
522        "An HTTP route path is malformed.",
523        &["http_handler"],
524    ),
525    dg(
526        "bynk.http.path_param_not_stringy",
527        "A path parameter's type is not constructible from a string.",
528        &["http_handler"],
529    ),
530    dg(
531        "bynk.http.reserved_prefix",
532        "A route uses the reserved `/_bynk/` prefix.",
533        &["http_handler"],
534    ),
535    dg(
536        "bynk.http.return_not_effect_http_result",
537        "An HTTP handler does not return `Effect[HttpResult[T]]`.",
538        &["http_handler"],
539    ),
540    dg(
541        "bynk.http.unbound_path_param",
542        "A `:name` route segment has no matching handler parameter.",
543        &["http_handler"],
544    ),
545    d(
546        "bynk.http.unknown_handler_annotation",
547        "A handler carries an annotation outside the closed set (`@cache`).",
548    ),
549    d(
550        "bynk.index.bad_argument",
551        "An `@indexed` argument is not a `by: <field>` label.",
552    ),
553    d(
554        "bynk.index.missing",
555        "A query filters a map by equality on a field that is not `@indexed` (a perf-hint warning).",
556    ),
557    d(
558        "bynk.index.unkeyable_key",
559        "An `@indexed(by: k)` field is not value-keyable.",
560    ),
561    d(
562        "bynk.index.unknown_key",
563        "An `@indexed(by: k)` field is not a field of the map's value type.",
564    ),
565    d(
566        "bynk.index.unused",
567        "A declared `@indexed(by: k)` is never used by an equality filter (a hygiene warning).",
568    ),
569    d(
570        "bynk.invariant.cross_agent_reference",
571        "An invariant predicate references another agent; invariants are per-agent.",
572    ),
573    d(
574        "bynk.invariant.duplicate_name",
575        "An agent declares two invariants with the same name.",
576    ),
577    d(
578        "bynk.invariant.impure_predicate",
579        "An invariant predicate uses an effectful or test-only construct.",
580    ),
581    d(
582        "bynk.invariant.not_bool",
583        "An invariant predicate does not have type `Bool`.",
584    ),
585    dg(
586        "bynk.lambda.unannotated_param",
587        "A lambda parameter has no type annotation in a position where no function type is expected to infer it from.",
588        &["lambda_expr"],
589    ),
590    dg(
591        "bynk.lex.bad_escape",
592        "An invalid escape sequence in a string literal.",
593        &["string_literal"],
594    ),
595    dg(
596        "bynk.lex.float_literal_overflow",
597        "A float literal does not fit a finite 64-bit float.",
598        &["float_literal"],
599    ),
600    dg(
601        "bynk.lex.integer_overflow",
602        "An integer literal is out of range.",
603        &["number_literal"],
604    ),
605    d(
606        "bynk.lex.unclosed_doc_block",
607        "A documentation block is not closed.",
608    ),
609    d(
610        "bynk.lex.unexpected_character",
611        "An unexpected character in the source.",
612    ),
613    dg(
614        "bynk.lex.unterminated_interpolation",
615        "An interpolation hole `\\(…)` is not closed on its line.",
616        &["string_literal"],
617    ),
618    dg(
619        "bynk.lex.unterminated_string",
620        "A string literal is not terminated.",
621        &["string_literal"],
622    ),
623    d(
624        "bynk.list.deprecated_function",
625        "A `bynk.list` free function (`map`/`filter`/`find`/`any`/`all`) is deprecated in favour of the `List` method form (warning; auto-fixable).",
626    ),
627    d(
628        "bynk.namespace.reserved",
629        "A user unit is named `bynk` or `bynk.*`; the `bynk` root is reserved for the toolchain.",
630    ),
631    d(
632        "bynk.observe.bad_count",
633        "An observation call count is not a non-negative integer literal (`called once` / `called <n> times`).",
634    ),
635    d(
636        "bynk.observe.impure_with",
637        "A `with` predicate uses an effectful or test-only construct; it must be pure.",
638    ),
639    d(
640        "bynk.observe.not_a_seam",
641        "An observation targets a capability the unit under test does not consume.",
642    ),
643    d(
644        "bynk.observe.outside_case",
645        "An observation appears outside a `case` body.",
646    ),
647    d(
648        "bynk.observe.trace_outside_test",
649        "`trace(Cap.op)` appears outside a `case` body.",
650    ),
651    d(
652        "bynk.observe.unknown_op",
653        "An observation names an operation the capability does not declare.",
654    ),
655    d(
656        "bynk.observe.with_not_bool",
657        "A `with` predicate does not have type `Bool`.",
658    ),
659    dg(
660        "bynk.parse.consumes_after_decls",
661        "`consumes` appears after other declarations.",
662        &["consumes_decl"],
663    ),
664    d(
665        "bynk.parse.dangling_handler_annotation",
666        "A handler-position annotation (e.g. `@cache`) is not followed by an `on` handler.",
667    ),
668    dg(
669        "bynk.parse.duplicate_cors",
670        "A service declares more than one `cors { }` policy.",
671        &["service_decl"],
672    ),
673    dg(
674        "bynk.parse.empty_agent",
675        "An `agent` body is empty.",
676        &["agent_decl"],
677    ),
678    dg(
679        "bynk.parse.empty_capability",
680        "A `capability` body is empty.",
681        &["capability_decl"],
682    ),
683    d(
684        "bynk.parse.empty_interpolation",
685        "An interpolation hole `\\(…)` contains no expression.",
686    ),
687    dg(
688        "bynk.parse.empty_match",
689        "A `match` has no arms.",
690        &["match_expr"],
691    ),
692    dg(
693        "bynk.parse.empty_service",
694        "A `service` body is empty.",
695        &["service_decl"],
696    ),
697    dg(
698        "bynk.parse.expected_agent_key",
699        "Expected a `key` declaration in an agent.",
700        &["agent_decl"],
701    ),
702    d(
703        "bynk.parse.expected_agent_storage",
704        "An agent declares no storage — it has no `store` fields.",
705    ),
706    dg(
707        "bynk.parse.expected_base_type",
708        "Expected a base type.",
709        &["base_type"],
710    ),
711    dg(
712        "bynk.parse.expected_capability_op",
713        "Expected a capability operation.",
714        &["capability_op"],
715    ),
716    d("bynk.parse.expected_expression", "Expected an expression."),
717    dg(
718        "bynk.parse.expected_handler",
719        "Expected a handler.",
720        &["handler"],
721    ),
722    d("bynk.parse.expected_item", "Expected a declaration."),
723    dg(
724        "bynk.parse.expected_predicate",
725        "Expected a refinement predicate.",
726        &["refinement"],
727    ),
728    dg(
729        "bynk.parse.expected_provider_op",
730        "Expected a provider operation.",
731        &["provider_op"],
732    ),
733    d("bynk.parse.expected_token", "Expected a specific token."),
734    d("bynk.parse.expected_type", "Expected a type."),
735    d(
736        "bynk.parse.expected_unit_header",
737        "Expected a `commons` or `context` header.",
738    ),
739    dg(
740        "bynk.parse.expected_visibility",
741        "Expected a visibility keyword.",
742        &["exports_decl"],
743    ),
744    dg(
745        "bynk.parse.exports_after_decls",
746        "`exports` appears after other declarations.",
747        &["exports_decl"],
748    ),
749    d(
750        "bynk.parse.extra_tokens",
751        "Unexpected tokens after an otherwise complete construct.",
752    ),
753    dg(
754        "bynk.parse.generic_arg_count",
755        "Wrong number of generic type arguments.",
756        &["generic_type_ref"],
757    ),
758    dg(
759        "bynk.parse.handler_in_agent",
760        "A protocol handler (`on GET`/`schedule`/`message`) was declared in an agent.",
761        &["handler"],
762    ),
763    d(
764        "bynk.parse.invariant_after_handler",
765        "An `invariant` was declared after a handler; invariants precede handlers.",
766    ),
767    dg(
768        "bynk.parse.malformed_float_literal",
769        "A float literal is missing a digit on one side of the `.` (`1.`, `.5`).",
770        &["float_literal"],
771    ),
772    dg(
773        "bynk.parse.non_associative",
774        "A non-associative operator was chained (e.g. `a == b == c`).",
775        &["binary_expr"],
776    ),
777    d(
778        "bynk.parse.orphan_doc_block",
779        "A documentation block is not attached to a declaration (warning).",
780    ),
781    dg(
782        "bynk.parse.reserved_keyword",
783        "A reserved keyword was used as an identifier.",
784        &["identifier"],
785    ),
786    dg(
787        "bynk.parse.self_outside_method",
788        "`self` used outside a method or handler.",
789        &["self_expr"],
790    ),
791    d(
792        "bynk.parse.storage_after_phase",
793        "Agent storage (`state` / `store`) is declared after the invariants or handlers.",
794    ),
795    d(
796        "bynk.parse.transition_after_handler",
797        "A `transition` is declared after an agent handler; step invariants precede the handlers.",
798    ),
799    d(
800        "bynk.parse.unexpected_adapter",
801        "An `adapter` appeared where it is not allowed.",
802    ),
803    dg(
804        "bynk.parse.unexpected_context",
805        "A `context` appeared where it is not allowed.",
806        &["context_decl"],
807    ),
808    d("bynk.parse.unexpected_eof", "Unexpected end of input."),
809    dg(
810        "bynk.parse.unexpected_suite",
811        "A `suite` appeared where it is not allowed.",
812        &["suite_decl"],
813    ),
814    d(
815        "bynk.parse.unknown_effect_method",
816        "An unknown method on `Effect`.",
817    ),
818    dg(
819        "bynk.parse.unknown_handler_kind",
820        "An unknown handler form (expected `call`, an HTTP method, `schedule`, or `message`).",
821        &["handler"],
822    ),
823    dg(
824        "bynk.parse.unknown_predicate",
825        "An unknown refinement predicate.",
826        &["predicate_name"],
827    ),
828    d(
829        "bynk.parse.unknown_tier",
830        "A `case`/`suite` `as <tier>` clause names something other than `unit`, `integration`, or `system`.",
831    ),
832    dg(
833        "bynk.parse.uses_after_decls",
834        "`uses` appears after other declarations.",
835        &["uses_decl"],
836    ),
837    d(
838        "bynk.project.file_and_directory",
839        "A unit exists as both a file and a directory.",
840    ),
841    d(
842        "bynk.project.inconsistent_commons_name",
843        "A source file's path does not match its declared name.",
844    ),
845    d(
846        "bynk.project.kind_conflict",
847        "A name is declared as both a commons and a context.",
848    ),
849    d(
850        "bynk.project.no_root",
851        "No project root could be determined.",
852    ),
853    d(
854        "bynk.project.no_sources",
855        "The project contains no source files.",
856    ),
857    d(
858        "bynk.project.read_failed",
859        "A source file could not be read.",
860    ),
861    dg(
862        "bynk.property.restates_refinement",
863        "A `property` merely re-checks a refinement its type already guarantees.",
864        &["for_all"],
865    ),
866    dg(
867        "bynk.property.where_not_bool",
868        "A `for all ... where` filter does not type to `Bool`.",
869        &["for_all"],
870    ),
871    dg(
872        "bynk.provider.dependency_cycle",
873        "Providers form a capability dependency cycle through `given`.",
874        &["provider_decl"],
875    ),
876    dg(
877        "bynk.provider.extra_operation",
878        "A `provides` block implements an operation not in the capability.",
879        &["provider_decl"],
880    ),
881    dg(
882        "bynk.provider.missing_operation",
883        "A `provides` block is missing a capability operation.",
884        &["provider_decl"],
885    ),
886    dg(
887        "bynk.provider.outside_context",
888        "`provides` was declared outside a context.",
889        &["provider_decl"],
890    ),
891    dg(
892        "bynk.provider.signature_mismatch",
893        "A `provides` operation's signature does not match the capability.",
894        &["provider_decl"],
895    ),
896    dg(
897        "bynk.provider.unknown_capability",
898        "`provides` names a capability that does not exist.",
899        &["provider_decl"],
900    ),
901    d(
902        "bynk.provides.bad_sequence",
903        "A `provides … returns each […]` sequence is malformed (e.g. empty).",
904    ),
905    d(
906        "bynk.provides.not_a_seam",
907        "A test `provides` overrides a capability the unit under test does not consume.",
908    ),
909    d(
910        "bynk.provides.rhs_type",
911        "A test `provides … returns <value>` right-hand side does not match the operation's return type.",
912    ),
913    d(
914        "bynk.provides.unknown_op",
915        "A test `provides` names an operation the capability does not declare.",
916    ),
917    d(
918        "bynk.query.join_key_mismatch",
919        "A `joinOn`/`leftJoin` left and right key function return different types.",
920    ),
921    dg(
922        "bynk.query.sum_needs_numeric",
923        "A `sum`/`average` key function does not return a numeric type (`Int`, `Float`, or `Duration`).",
924        &[],
925    ),
926    dg(
927        "bynk.queue.bad_params",
928        "An `on message` handler does not take exactly one `message` parameter.",
929        &["queue_handler"],
930    ),
931    dg(
932        "bynk.queue.duplicate_consumer",
933        "Two `on message` handlers consume the same queue.",
934        &["queue_handler"],
935    ),
936    dg(
937        "bynk.queue.invalid_name",
938        "A `from queue(\"…\")` binding has an empty queue name.",
939        &["queue_handler"],
940    ),
941    dg(
942        "bynk.queue.return_not_queue_result",
943        "An `on message` handler does not return `Effect[QueueResult]`.",
944        &["handler"],
945    ),
946    dg(
947        "bynk.record_spread.field_type_mismatch",
948        "A record-spread override has the wrong type for the field.",
949        &["record_spread"],
950    ),
951    dg(
952        "bynk.record_spread.non_record_base",
953        "The base of a record spread is not a record.",
954        &["record_spread"],
955    ),
956    dg(
957        "bynk.record_spread.type_mismatch",
958        "A record spread's base is a different record type.",
959        &["record_spread"],
960    ),
961    dg(
962        "bynk.record_spread.unknown_field",
963        "A record spread overrides a field the record does not have.",
964        &["record_spread"],
965    ),
966    dg(
967        "bynk.refine.literal_violates",
968        "A literal does not satisfy the refined type's predicate.",
969        &["refined_type"],
970    ),
971    dg(
972        "bynk.requires.unpinned_dependency",
973        "An adapter `binding … requires { … }` entry has an unpinned version range.",
974        &["binding_decl"],
975    ),
976    d(
977        "bynk.resolve.ambiguous_variant",
978        "A variant name is ambiguous across several sum types.",
979    ),
980    dg(
981        "bynk.resolve.arity_mismatch",
982        "A function was called with the wrong number of arguments.",
983        &["call"],
984    ),
985    d("bynk.resolve.duplicate_actor", "Two actors share a name."),
986    dg(
987        "bynk.resolve.duplicate_agent",
988        "Two agents share a name.",
989        &["agent_decl"],
990    ),
991    dg(
992        "bynk.resolve.duplicate_capability",
993        "Two capabilities share a name.",
994        &["capability_decl"],
995    ),
996    dg(
997        "bynk.resolve.duplicate_field",
998        "A record declares a field twice.",
999        &["record_type"],
1000    ),
1001    dg(
1002        "bynk.resolve.duplicate_field_init",
1003        "A record construction initialises a field twice.",
1004        &["record_construction"],
1005    ),
1006    dg(
1007        "bynk.resolve.duplicate_fn",
1008        "Two functions share a name.",
1009        &["fn_decl"],
1010    ),
1011    dg(
1012        "bynk.resolve.duplicate_method",
1013        "Two methods share a name.",
1014        &["fn_decl"],
1015    ),
1016    dg(
1017        "bynk.resolve.duplicate_param",
1018        "A parameter name is repeated.",
1019        &["param"],
1020    ),
1021    dg(
1022        "bynk.resolve.duplicate_provider",
1023        "A capability is provided more than once.",
1024        &["provider_decl"],
1025    ),
1026    dg(
1027        "bynk.resolve.duplicate_service",
1028        "Two services share a name.",
1029        &["service_decl"],
1030    ),
1031    dg(
1032        "bynk.resolve.duplicate_type",
1033        "Two types share a name.",
1034        &["type_decl"],
1035    ),
1036    dg(
1037        "bynk.resolve.duplicate_variant",
1038        "A sum type declares a variant twice.",
1039        &["sum_type"],
1040    ),
1041    d(
1042        "bynk.resolve.fn_without_call",
1043        "A function was referenced without being called.",
1044    ),
1045    dg(
1046        "bynk.resolve.let_shadows_fn",
1047        "A `let` binding shadows a function.",
1048        &["let_stmt"],
1049    ),
1050    dg(
1051        "bynk.resolve.let_shadows_type",
1052        "A `let` binding shadows a type.",
1053        &["let_stmt"],
1054    ),
1055    d(
1056        "bynk.resolve.method_unknown_type",
1057        "A method is defined on an unknown type.",
1058    ),
1059    dg(
1060        "bynk.resolve.missing_field",
1061        "A record construction omits a required field.",
1062        &["record_construction"],
1063    ),
1064    d(
1065        "bynk.resolve.name_conflict",
1066        "Two declarations share a name.",
1067    ),
1068    dg(
1069        "bynk.resolve.not_a_record_type",
1070        "Record syntax was used on a non-record type.",
1071        &["record_construction"],
1072    ),
1073    dg(
1074        "bynk.resolve.opaque_record_construction",
1075        "An opaque type was constructed with record syntax.",
1076        &["record_construction"],
1077    ),
1078    dg(
1079        "bynk.resolve.param_as_function",
1080        "A value (such as a parameter) was called as a function.",
1081        &["call"],
1082    ),
1083    dg(
1084        "bynk.resolve.recursive_record_field",
1085        "A record directly contains a field of its own type.",
1086        &["record_type"],
1087    ),
1088    dg(
1089        "bynk.resolve.self_outside_method",
1090        "`self` referenced outside a method or handler.",
1091        &["self_expr"],
1092    ),
1093    dg(
1094        "bynk.resolve.type_as_function",
1095        "A type name was called as if it were a function.",
1096        &["call"],
1097    ),
1098    d(
1099        "bynk.resolve.type_in_expr",
1100        "A type name was used where a value is expected.",
1101    ),
1102    dg(
1103        "bynk.resolve.unconsumed_context",
1104        "A context's service was called without a `consumes` declaration.",
1105        &["consumes_decl"],
1106    ),
1107    dg(
1108        "bynk.resolve.unknown_field",
1109        "Accessed a field the record does not have.",
1110        &["field_access"],
1111    ),
1112    dg(
1113        "bynk.resolve.unknown_function",
1114        "Called a function that does not exist.",
1115        &["call"],
1116    ),
1117    d(
1118        "bynk.resolve.unknown_name",
1119        "Referenced a name that is not in scope.",
1120    ),
1121    dg(
1122        "bynk.resolve.unknown_static_member",
1123        "Referenced an unknown static member (e.g. `T.x`).",
1124        &["field_access"],
1125    ),
1126    d(
1127        "bynk.resolve.unknown_type",
1128        "Referenced a type that does not exist.",
1129    ),
1130    dg(
1131        "bynk.send.in_pure_context",
1132        "A `~>` send was used in a pure (non-effectful) context.",
1133        &["effect_send_stmt"],
1134    ),
1135    dg(
1136        "bynk.send.non_effect",
1137        "A `~>` send was applied to a non-`Effect` value.",
1138        &["effect_send_stmt"],
1139    ),
1140    dg(
1141        "bynk.send.requires_unit",
1142        "A `~>` send targets an operation whose reply is not `Effect[()]`.",
1143        &["effect_send_stmt"],
1144    ),
1145    dg(
1146        "bynk.service.missing_from",
1147        "A `from`-less service has a handler other than `on call`.",
1148        &["service_decl"],
1149    ),
1150    dg(
1151        "bynk.service.mixed_protocols",
1152        "A service mixes handler forms that do not match its `from <protocol>`.",
1153        &["service_decl"],
1154    ),
1155    dg(
1156        "bynk.service.outside_context",
1157        "A `service` was declared outside a context.",
1158        &["service_decl"],
1159    ),
1160    dg(
1161        "bynk.service.return_not_effect",
1162        "A service handler's return type is not an `Effect`.",
1163        &["service_decl"],
1164    ),
1165    dg(
1166        "bynk.service.unknown_protocol",
1167        "A `from <protocol>` names an unknown protocol (e.g. a transport like Kafka).",
1168        &["service_decl"],
1169    ),
1170    d(
1171        "bynk.service.websocket_header",
1172        "The `from WebSocket` header is malformed — it binds frame types as `WebSocket(in: <type>, out: <type>)` (real-time track slice 3).",
1173    ),
1174    d(
1175        "bynk.service.websocket_multiple",
1176        "A context holds more than one `from WebSocket` service — at v1 the Workers upgrade routes by the `Upgrade: websocket` header alone, so one WebSocket service per context (real-time track slice 3b).",
1177    ),
1178    d(
1179        "bynk.service.websocket_open_arity",
1180        "A `from WebSocket` service must hold exactly one `on open` handler (the edge upgrade), and at most one `on message` (inbound) and one `on close` (real-time track slice 3/3b-iii).",
1181    ),
1182    d(
1183        "bynk.store.annotation_kind_mismatch",
1184        "A storage annotation is used on a kind it does not apply to (e.g. `@ttl` on a `Map`).",
1185    ),
1186    d(
1187        "bynk.store.annotation_unsupported",
1188        "A known storage annotation (`@ttl`/`@retain`/`@indexed`/`@bounded`) is used before the slice that supports it.",
1189    ),
1190    d(
1191        "bynk.store.cache_needs_clock",
1192        "A handler performs a `Cache` operation (TTL expiry reads the clock) without declaring `given Clock`.",
1193    ),
1194    d(
1195        "bynk.store.cache_ttl_required",
1196        "A `Cache` field is missing its required `@ttl(<duration>)` annotation (a keyed store with no expiry is a `Map`).",
1197    ),
1198    d(
1199        "bynk.store.kind_arity",
1200        "A storage kind was applied to the wrong number of type arguments (e.g. `Cell[A, B]`).",
1201    ),
1202    d(
1203        "bynk.store.kind_unsupported",
1204        "A known storage kind (`Queue`) is used before the slice that supports it.",
1205    ),
1206    d(
1207        "bynk.store.log_needs_clock",
1208        "A handler calls `Log.append` (which stamps the current time) without declaring `given Clock`.",
1209    ),
1210    d(
1211        "bynk.store.unknown_annotation",
1212        "A `store` field carries an annotation outside the closed `@indexed`/`@ttl`/`@retain`/`@bounded` set.",
1213    ),
1214    d(
1215        "bynk.store.unknown_kind",
1216        "A `store` field's type is not a known storage kind.",
1217    ),
1218    d(
1219        "bynk.store.unknown_op",
1220        "A storage-`Map`/`Set` operation is not a recognised entry/membership method.",
1221    ),
1222    dg(
1223        "bynk.suite.duplicate_case_name",
1224        "Two `case`s share a description.",
1225        &["case"],
1226    ),
1227    dg(
1228        "bynk.suite.unknown_target",
1229        "A `suite` targets a unit that does not exist.",
1230        &["suite_decl"],
1231    ),
1232    d(
1233        "bynk.target.browser_bundle_only",
1234        "The `browser` platform builds only the in-process `Bundle` topology; `--target workers` is not a browser build.",
1235    ),
1236    dg(
1237        "bynk.target.vendor_conflict",
1238        "One deployment unit's in-process closure uses platform-native capabilities from two mutually-exclusive platforms.",
1239        &["consumes_decl"],
1240    ),
1241    dg(
1242        "bynk.target.vendor_required",
1243        "A deployment unit uses a platform-native capability but the build selects another `--platform`.",
1244        &["consumes_decl"],
1245    ),
1246    d(
1247        "bynk.tier.property_has_tier",
1248        "A `property` carries an `as <tier>` clause; tiers are a `case`-only affordance.",
1249    ),
1250    d(
1251        "bynk.tier.system_needs_wire",
1252        "An `as system` test stands up fewer than two contexts; the system tier wires across contexts.",
1253    ),
1254    d(
1255        "bynk.transition.cross_agent_reference",
1256        "A transition predicate references another agent; step invariants are per-agent.",
1257    ),
1258    d(
1259        "bynk.transition.duplicate_name",
1260        "An agent declares two transitions with the same name.",
1261    ),
1262    d(
1263        "bynk.transition.impure_predicate",
1264        "A transition predicate uses an effectful or test-only construct; a step invariant must be pure.",
1265    ),
1266    d(
1267        "bynk.transition.no_step_reference",
1268        "A transition references neither `old` nor `new`; it constrains one state, so it is an `invariant`, not a step.",
1269    ),
1270    d(
1271        "bynk.transition.not_bool",
1272        "A transition predicate does not have type `Bool`.",
1273    ),
1274    d(
1275        "bynk.types.ambiguous_constructor",
1276        "`Ok`/`Err` is ambiguous between `Result` and `HttpResult`; qualify it.",
1277    ),
1278    dg(
1279        "bynk.types.argument_mismatch",
1280        "A function argument has the wrong type.",
1281        &["call"],
1282    ),
1283    d(
1284        "bynk.types.bytes_at_workers_boundary",
1285        "A bare `Bytes` appears in a `workers` wire signature — the erased cross-context boundary does not base64-encode it, so v1 diagnoses it rather than mis-encode. The typed paths (`bundle` calls, `store`/record fields) round-trip a `Bytes` fine (ADR 0142 D8).",
1286    ),
1287    dg(
1288        "bynk.types.call_arity",
1289        "A function value was applied with the wrong number of arguments.",
1290        &["call"],
1291    ),
1292    dg(
1293        "bynk.types.cannot_infer_option_type_param",
1294        "The value type of `None` could not be inferred.",
1295        &["none_expr"],
1296    ),
1297    d(
1298        "bynk.types.cannot_infer_result_type_params",
1299        "The type parameters of a `Result` could not be inferred.",
1300    ),
1301    d(
1302        "bynk.types.constructor_arity",
1303        "A variant constructor got the wrong number of arguments.",
1304    ),
1305    d(
1306        "bynk.types.constructor_base_mismatch",
1307        "A `.of` constructor was given an argument of the wrong base type.",
1308    ),
1309    dg(
1310        "bynk.types.duplicate_literal_arm",
1311        "A `match` has two arms for the same literal value.",
1312        &["match_arm"],
1313    ),
1314    dg(
1315        "bynk.types.duplicate_variant_arm",
1316        "A `match` has two arms for the same variant.",
1317        &["match_arm"],
1318    ),
1319    dg(
1320        "bynk.types.empty_refinement",
1321        "A refinement admits no values (contradictory predicates).",
1322        &["refinement"],
1323    ),
1324    dg(
1325        "bynk.types.err_value_mismatch",
1326        "An `Err` payload has the wrong type.",
1327        &["err_expr"],
1328    ),
1329    dg(
1330        "bynk.types.field_access_on_non_record",
1331        "Field access on a value that is not a record.",
1332        &["field_access"],
1333    ),
1334    dg(
1335        "bynk.types.field_refinement_not_base",
1336        "An inline field refinement requires a base or refined type.",
1337        &["record_field"],
1338    ),
1339    dg(
1340        "bynk.types.field_value_mismatch",
1341        "A record field was given a value of the wrong type.",
1342        &["record_construction"],
1343    ),
1344    dg(
1345        "bynk.types.function_at_boundary",
1346        "A function type appeared in a serialisable or boundary position (a record field, sum payload, service/agent handler signature, capability operation signature, agent state field, or agent key); functions cannot serialise or cross a boundary.",
1347        &["function_type_ref"],
1348    ),
1349    d(
1350        "bynk.types.held_at_boundary",
1351        "A held value (`Connection[F]`) appears in a serialisable or boundary position — a held resource is built and disposed in place, never persisted or sent across a boundary (§2.9, real-time track slice 2).",
1352    ),
1353    d(
1354        "bynk.types.held_not_comparable",
1355        "A held value (`Connection[F]`) is compared with `==`/`!=` — held values have identity, not value-equality (§2.9.3, real-time track slice 2).",
1356    ),
1357    dg(
1358        "bynk.types.if_branch_mismatch",
1359        "The branches of an `if` have different types.",
1360        &["if_expr"],
1361    ),
1362    dg(
1363        "bynk.types.if_non_bool_cond",
1364        "An `if` condition is not a `Bool`.",
1365        &["if_expr"],
1366    ),
1367    d(
1368        "bynk.types.interpolation_non_scalar",
1369        "An interpolation hole holds a value with no string form.",
1370    ),
1371    dg(
1372        "bynk.types.invalid_regex",
1373        "A `Matches` predicate contains an invalid regular expression.",
1374        &["refinement"],
1375    ),
1376    dg(
1377        "bynk.types.inverted_range",
1378        "An `InRange` predicate has its bounds inverted.",
1379        &["refinement"],
1380    ),
1381    dg(
1382        "bynk.types.is_base_mismatch",
1383        "An `is` refinement check is applied to a value of the wrong base type.",
1384        &["is_expr"],
1385    ),
1386    dg(
1387        "bynk.types.is_literal_pattern",
1388        "A literal was used on the right of `is`; `is` tests type/refinement, not value equality (use `==`).",
1389        &["is_expr"],
1390    ),
1391    dg(
1392        "bynk.types.is_non_sum",
1393        "`is` was applied to a value that is not a sum type.",
1394        &["is_expr"],
1395    ),
1396    dg(
1397        "bynk.types.is_unknown_variant",
1398        "`is` names a variant the type does not have.",
1399        &["is_expr"],
1400    ),
1401    dg(
1402        "bynk.types.json_uncodable",
1403        "A `Json.encode`/`Json.decode` target type cannot pass through the typed JSON codec (functions, effects, error builtins).",
1404        &["method_call"],
1405    ),
1406    dg(
1407        "bynk.types.key_not_orderable",
1408        "A `sortBy`/`min`/`max` key function does not return an orderable type (`Int`, `Float`, `String`, `Duration`, or `Instant`).",
1409        &[],
1410    ),
1411    dg(
1412        "bynk.types.lambda_mismatch",
1413        "A lambda's parameter count, parameter annotations, or body type do not match the expected function type.",
1414        &["lambda_expr"],
1415    ),
1416    dg(
1417        "bynk.types.let_annotation_mismatch",
1418        "A `let` value does not match its type annotation.",
1419        &["let_stmt"],
1420    ),
1421    dg(
1422        "bynk.types.list_element_mismatch",
1423        "A list-literal element has a different type from the list's element type.",
1424        &["list_literal"],
1425    ),
1426    dg(
1427        "bynk.types.match_arm_mismatch",
1428        "A `match` arm has a different type from the others.",
1429        &["match_arm"],
1430    ),
1431    dg(
1432        "bynk.types.match_non_sum_discriminant",
1433        "`match` was applied to a value that is not a sum type.",
1434        &["match_expr"],
1435    ),
1436    dg(
1437        "bynk.types.method_arity",
1438        "A method was called with the wrong number of arguments.",
1439        &["method_call"],
1440    ),
1441    dg(
1442        "bynk.types.method_not_found",
1443        "Called a method the type does not have.",
1444        &["method_call"],
1445    ),
1446    dg(
1447        "bynk.types.method_on_non_named_type",
1448        "A method was called on a built-in type that has no methods.",
1449        &["method_call"],
1450    ),
1451    dg(
1452        "bynk.types.mixed_pattern_bindings",
1453        "A pattern mixes named and positional bindings.",
1454        &["variant_pattern"],
1455    ),
1456    dg(
1457        "bynk.types.negative_length",
1458        "A length predicate was given a negative value.",
1459        &["refinement"],
1460    ),
1461    dg(
1462        "bynk.types.no_numeric_coercion",
1463        "`Int` and `Float` were mixed without an explicit conversion — in an operation or in refinement bounds.",
1464        &["binary_expr", "refinement"],
1465    ),
1466    dg(
1467        "bynk.types.non_exhaustive_match",
1468        "A `match` does not cover every variant.",
1469        &["match_expr"],
1470    ),
1471    dg(
1472        "bynk.types.ok_value_mismatch",
1473        "An `Ok` payload has the wrong type.",
1474        &["ok_expr"],
1475    ),
1476    dg(
1477        "bynk.types.opaque_raw_outside",
1478        "`.raw` on an opaque type was used outside its defining commons.",
1479        &["field_access"],
1480    ),
1481    dg(
1482        "bynk.types.opaque_record_construction",
1483        "An opaque type was constructed with record syntax.",
1484        &["record_construction"],
1485    ),
1486    dg(
1487        "bynk.types.opaque_unsafe_outside",
1488        "`.unsafe` on an opaque type was used outside its defining context.",
1489        &["field_access"],
1490    ),
1491    dg(
1492        "bynk.types.pattern_arity",
1493        "A pattern binds the wrong number of payload fields.",
1494        &["variant_pattern"],
1495    ),
1496    dg(
1497        "bynk.types.pattern_type_mismatch",
1498        "A pattern's type does not match the matched value.",
1499        &["variant_pattern"],
1500    ),
1501    dg(
1502        "bynk.types.predicate_base_mismatch",
1503        "A predicate does not apply to the type's base (e.g. a string predicate on an `Int`).",
1504        &["refinement"],
1505    ),
1506    d(
1507        "bynk.types.query_at_boundary",
1508        "A `Query` type appears in a storable or boundary-crossing position — a query is built and executed in place, never persisted or sent (ADR 0115).",
1509    ),
1510    dg(
1511        "bynk.types.question_error_mismatch",
1512        "`?` propagates an error type incompatible with the function's.",
1513        &["question_expr"],
1514    ),
1515    dg(
1516        "bynk.types.question_on_non_result",
1517        "`?` was applied to a non-`Result` value.",
1518        &["question_expr"],
1519    ),
1520    dg(
1521        "bynk.types.question_outside_result",
1522        "`?` used in a function that does not return a `Result`.",
1523        &["question_expr"],
1524    ),
1525    d(
1526        "bynk.types.return_mismatch",
1527        "A returned value does not match the declared return type.",
1528    ),
1529    dg(
1530        "bynk.types.some_value_mismatch",
1531        "A `Some` payload has the wrong type.",
1532        &["some_expr"],
1533    ),
1534    d(
1535        "bynk.types.stream_at_boundary",
1536        "A `Stream` type appears in a storable or boundary-crossing position — a stream is a live value-over-time source, never persisted or sent across a boundary (real-time track slice 0).",
1537    ),
1538    d(
1539        "bynk.types.stream_not_comparable",
1540        "A `Stream` value is compared with `==`/`!=` — a stream is a live value-over-time source, not a comparable value (real-time track slice 0).",
1541    ),
1542    d(
1543        "bynk.types.type_mismatch",
1544        "Two types that were required to match did not.",
1545    ),
1546    dg(
1547        "bynk.types.uninferable_element_type",
1548        "An empty `[]` (or `List.empty()` / `Map.empty()`) has no expected type to infer its element type from.",
1549        &["list_literal"],
1550    ),
1551    dg(
1552        "bynk.types.unkeyable_distinct",
1553        "A `distinct`/`distinctBy` element or key is not value-keyable (`String`, `Int`, or a refined/opaque type over them).",
1554        &[],
1555    ),
1556    dg(
1557        "bynk.types.unkeyable_map_key",
1558        "A `Map` key type is not value-keyable (`String`, `Int`, or a refined/opaque type over them).",
1559        &["generic_type_ref"],
1560    ),
1561    dg(
1562        "bynk.types.unknown_field",
1563        "Referenced a field the record type does not declare.",
1564        &["field_access"],
1565    ),
1566    dg(
1567        "bynk.types.unknown_pattern_field",
1568        "A pattern names a field the variant does not have.",
1569        &["variant_pattern"],
1570    ),
1571    dg(
1572        "bynk.types.unknown_static_member",
1573        "Referenced an unknown static member on a type.",
1574        &["field_access"],
1575    ),
1576    dg(
1577        "bynk.types.unknown_variant_in_pattern",
1578        "A pattern names a variant the sum type does not have.",
1579        &["variant_pattern"],
1580    ),
1581    dg(
1582        "bynk.types.unreachable_arm",
1583        "A `match` arm is unreachable.",
1584        &["match_arm"],
1585    ),
1586    d(
1587        "bynk.types.variant_arity",
1588        "A variant constructor got the wrong number of payload values.",
1589    ),
1590    d(
1591        "bynk.types.variant_missing_payload",
1592        "A variant requiring a payload was used without one.",
1593    ),
1594    d(
1595        "bynk.types.variant_payload_mismatch",
1596        "A variant payload has the wrong type.",
1597    ),
1598    dg(
1599        "bynk.uses.name_conflict",
1600        "A `uses` name collides with another name.",
1601        &["uses_decl"],
1602    ),
1603    dg(
1604        "bynk.uses.self_reference",
1605        "A commons `uses` itself.",
1606        &["uses_decl"],
1607    ),
1608    dg(
1609        "bynk.uses.target_is_context",
1610        "`uses` targets a context instead of a commons.",
1611        &["uses_decl"],
1612    ),
1613    dg(
1614        "bynk.uses.unknown_commons",
1615        "`uses` names a commons that does not exist.",
1616        &["uses_decl"],
1617    ),
1618    dg(
1619        "bynk.val.agent_not_generable",
1620        "A `for all`/`Val` cannot generate an agent — fabricated agent states need not be reachable.",
1621        &["for_all"],
1622    ),
1623    dg(
1624        "bynk.val.arity",
1625        "`Val[T]` was given the wrong number of pin arguments.",
1626        &["val_expr"],
1627    ),
1628    dg(
1629        "bynk.val.literal_violates",
1630        "A pinned `Val[T]` value violates the type's refinement.",
1631        &["val_expr"],
1632    ),
1633    dg(
1634        "bynk.val.needs_pin",
1635        "A bare `Val[T]` cannot generate a value (e.g. a `Matches` string); pin one.",
1636        &["val_expr"],
1637    ),
1638    dg(
1639        "bynk.val.outside_test",
1640        "`Val[T]` was used outside a test case body.",
1641        &["val_expr"],
1642    ),
1643    dg(
1644        "bynk.val.pin_not_literal",
1645        "A `Val[T]` pin argument is not a compile-time literal.",
1646        &["val_expr"],
1647    ),
1648    dg(
1649        "bynk.val.pin_unsupported",
1650        "A pin was given for a type kind that does not support pinning.",
1651        &["val_expr"],
1652    ),
1653    dg(
1654        "bynk.val.unknown_type",
1655        "`Val[T]` names a type that does not resolve.",
1656        &["val_expr"],
1657    ),
1658    dg(
1659        "bynk.val.unsupported_kind",
1660        "`Val[T]` cannot fabricate a value for this kind of type.",
1661        &["val_expr"],
1662    ),
1663    d(
1664        "bynk.ws.message_frame_param",
1665        "A WebSocket `on message` handler does not have exactly one parameter of the service's inbound (`in:`) frame type — the decoded frame (real-time track slice 3b-iii).",
1666    ),
1667    d(
1668        "bynk.ws.open_given_unsupported",
1669        "A WebSocket `on open` handler declares `given` capabilities — unsupported at v1, since on Workers the handler runs inside the connection-hosting Durable Object, which has no composition root to supply them (real-time track slice 3b).",
1670    ),
1671    d(
1672        "bynk.ws.open_transfer_shape",
1673        "A WebSocket `on open` handler does not transfer its `connection` into exactly one agent, so the Workers upgrade has no single Durable Object to route to (real-time track slice 3b).",
1674    ),
1675    d(
1676        "bynk.ws.route_param_mismatch",
1677        "A WebSocket `on message`/`on close` route parameter does not match the `on open` parameter at the same position — route values are recovered positionally from the connection, so they must be a type-compatible prefix of the `on open` parameters (real-time track slice 3b-iii).",
1678    ),
1679];
1680
1681/// A diagnostic with no single governing grammar construct.
1682const fn d(code: &'static str, summary: &'static str) -> DiagnosticInfo {
1683    DiagnosticInfo {
1684        code,
1685        summary,
1686        grammar_symbol: &[],
1687    }
1688}
1689
1690/// A diagnostic that constrains one or more grammar productions.
1691const fn dg(
1692    code: &'static str,
1693    summary: &'static str,
1694    grammar_symbol: &'static [&'static str],
1695) -> DiagnosticInfo {
1696    DiagnosticInfo {
1697        code,
1698        summary,
1699        grammar_symbol,
1700    }
1701}
1702
1703/// The category segment of a code (the part between the first two dots), e.g.
1704/// `"types"` for `"bynk.types.type_mismatch"`.
1705pub fn category(code: &str) -> &str {
1706    code.split('.').nth(1).unwrap_or("")
1707}
1708
1709/// A human-readable heading for a category segment.
1710fn category_title(cat: &str) -> &'static str {
1711    match cat {
1712        "agent" | "agents" => "Agents",
1713        "boundary" => "Boundaries",
1714        "capability" => "Capabilities",
1715        "consumes" => "Consumes",
1716        "context" => "Contexts",
1717        "contract" => "Contracts",
1718        "cron" => "Cron",
1719        "effect" => "Effects",
1720        "expect" => "Expectations",
1721        "exports" => "Exports",
1722        "given" => "Given capabilities",
1723        "http" => "HTTP",
1724        "lex" => "Lexer",
1725        "mock" => "Mocks (collaborators)",
1726        "observe" => "Observation",
1727        "parse" => "Parser",
1728        "project" => "Project",
1729        "property" => "Properties (generative tests)",
1730        "provider" => "Providers",
1731        "queue" => "Queue",
1732        "record_spread" => "Record spread",
1733        "refine" => "Refinement",
1734        "resolve" => "Resolution",
1735        "service" => "Services",
1736        "suite" => "Suites and cases",
1737        "transition" => "Transitions (step invariants)",
1738        "types" => "Type checking",
1739        "uses" => "Uses",
1740        "val" => "Value fabrication",
1741        _ => "Other",
1742    }
1743}
1744
1745/// Render the diagnostic index as a Markdown reference page, grouped by
1746/// category. This is the generator behind
1747/// `site/src/content/docs/book/reference/diagnostics.md`.
1748pub fn render_markdown() -> String {
1749    use std::collections::BTreeMap;
1750
1751    // Group codes by their category title, preserving sorted code order.
1752    let mut by_category: BTreeMap<&str, Vec<&DiagnosticInfo>> = BTreeMap::new();
1753    for info in REGISTRY {
1754        by_category
1755            .entry(category_title(category(info.code)))
1756            .or_default()
1757            .push(info);
1758    }
1759
1760    let mut out = String::new();
1761    out.push_str("# Diagnostic index\n\n");
1762    out.push_str(
1763        "<!-- GENERATED FILE — do not edit by hand.\n     \
1764         Source: bynkc/src/diagnostics.rs (`render_markdown`).\n     \
1765         Regenerate with: BYNK_BLESS=1 cargo test -p bynkc --test diagnostics_registry -->\n\n",
1766    );
1767    out.push_str(
1768        "Every diagnostic code the compiler can emit, with a one-line summary of \
1769         the cause, grouped by category. For step-by-step cause-and-fix guidance \
1770         on the most common ones, see the [troubleshooting guides](../troubleshooting/index.md).\n\n",
1771    );
1772    out.push_str(&format!(
1773        "There are **{}** codes in total.\n",
1774        REGISTRY.len()
1775    ));
1776
1777    for (title, infos) in &by_category {
1778        out.push_str(&format!("\n## {title}\n\n"));
1779        out.push_str("| Code | Summary | Construct |\n|---|---|---|\n");
1780        for info in infos {
1781            // The construct column deep-links each governing production to its
1782            // entry in the annotated grammar reference; generated from
1783            // `grammar_symbol` (each value is an embeddable rule, so the
1784            // `#rule-<raw>` anchor resolves — enforced in diagnostics_registry).
1785            let construct = info
1786                .grammar_symbol
1787                .iter()
1788                .map(|sym| format!("[`{sym}`](grammar.md#rule-{sym})"))
1789                .collect::<Vec<_>>()
1790                .join(", ");
1791            out.push_str(&format!(
1792                "| `{}` | {} | {} |\n",
1793                info.code, info.summary, construct
1794            ));
1795        }
1796    }
1797
1798    out
1799}
1800
1801/// Invert the registry into a `{ "<rule>": [ { code, summary }, … ], … }` map,
1802/// serialised as pretty JSON with sorted keys and sorted codes. Only rules with
1803/// at least one diagnostic appear. This is the generator behind
1804/// `docs/grammar-semantics.json`, which the `{{#grammar-semantics <rule>}}`
1805/// preprocessor directive consumes.
1806pub fn render_grammar_semantics_json() -> String {
1807    use std::collections::BTreeMap;
1808
1809    // REGISTRY is sorted by code, so each rule's vector comes out code-sorted;
1810    // the BTreeMap gives sorted rule names.
1811    let mut by_symbol: BTreeMap<&str, Vec<&DiagnosticInfo>> = BTreeMap::new();
1812    for info in REGISTRY {
1813        for sym in info.grammar_symbol {
1814            by_symbol.entry(sym).or_default().push(info);
1815        }
1816    }
1817
1818    let mut map = serde_json::Map::new();
1819    map.insert(
1820        "_generated".to_string(),
1821        serde_json::Value::String(
1822            "Generated from the grammar_symbol field of bynkc/src/diagnostics.rs. \
1823             Do not edit by hand. Regenerate with: BYNK_BLESS=1 cargo test -p \
1824             bynkc --test diagnostics_registry"
1825                .to_string(),
1826        ),
1827    );
1828    for (sym, infos) in by_symbol {
1829        let arr: Vec<serde_json::Value> = infos
1830            .iter()
1831            .map(|info| serde_json::json!({ "code": info.code, "summary": info.summary }))
1832            .collect();
1833        map.insert(sym.to_string(), serde_json::Value::Array(arr));
1834    }
1835
1836    let mut s =
1837        serde_json::to_string_pretty(&serde_json::Value::Object(map)).expect("serialise semantics");
1838    s.push('\n');
1839    s
1840}