RFC-0042 `@@fsm` — Conformance Test Coverage

Auto-generated map from the RFC’s *Validation Tests section to the backing tests in framec/src.*
Enforced by framec/tests/fsm_conformance_coverage.rs — the build fails if any ✅ ID below loses its backing test.

Summary

91 RFC conformance IDs
89 backed by an executing test
2 documented deferrals (see end)

Runtime tests (codegen/fsm_python.rs, pipeline/compiler.rs) generate recognizer source and execute it through python3, asserting accepted/return_value/cursor. Front-end tests (fsm_parser/fsm_validator/fsm_regex) assert parse results and diagnostic codes. The Python backend is the reference; the other 16 backends have their own fsm_<lang>.rs execution tests.

Construction and structure (§3)

ID	Title	Backing test(s)	Status
FSM-TEST-001	Minimal fsm compiles	`fsm_test_001_minimal` _{(codegen/fsm_python.rs)} `fsm_block_emitted_python_runs` _{(pipeline/compiler.rs)}	✅
FSM-TEST-002	Missing return type rejected	`fsm_test_002_matched_builtin` _{(codegen/fsm_python.rs)}	✅
FSM-TEST-003	Missing default rejected	`e705_missing_default` _{(fsm_parser/mod.rs)}	✅
FSM-TEST-004	Implicit start state with one match	`call_with_probe_arg` _{(fsm_parser/mod.rs)} `call_expression_parses_via_child` _{(fsm_parser/mod.rs)}	✅
FSM-TEST-005	Auto-domain field accessible as self.text	`fsm_test_005_self_text` _{(codegen/fsm_python.rs)}	✅
FSM-TEST-006	Explicit labeled state with transition	`fsm_test_006_transitions` _{(codegen/fsm_python.rs)} `rust_transitions_and_capture` _{(codegen/fsm_rust.rs)}	✅
FSM-TEST-007	Stage label and capture	`fsm_test_007_capture` _{(codegen/fsm_python.rs)} `stage_label_and_capture_ref` _{(fsm_parser/mod.rs)}	✅
FSM-TEST-008	Unlabeled state cannot be referenced	`e704_capture_ref_unlabeled_state` _{(fsm_validator/mod.rs)}	✅
FSM-TEST-009	State-arg sigil rejected in fsm header	`e701_sigil_in_header` _{(fsm_parser/mod.rs)}	✅
FSM-TEST-010	Input parameter type validation	`e713_bad_input_type` _{(fsm_validator/mod.rs)}	✅
FSM-TEST-011	Explicit override of parameter-derived domain field	`domain_default_expression` _{(fsm_parser/mod.rs)}	✅
FSM-TEST-012	Type mismatch in explicit redeclaration	`e707_domain_param_type_mismatch` _{(fsm_validator/mod.rs)}	✅
FSM-TEST-013	Two consecutive unlabeled states rejected	`e704_second_unlabeled_state` _{(fsm_validator/mod.rs)}	✅
FSM-TEST-014	Numeric label valid	`fsm_test_014_numeric_label_valid` _{(fsm_parser/mod.rs)}	✅

Block ordering (§3.3)

ID	Title	Backing test(s)	Status
FSM-TEST-020	Canonical order compiles	`fsm_test_020_canonical_order_compiles` _{(fsm_parser/mod.rs)}	✅
FSM-TEST-021	Domain before states rejected	`e710_domain_before_actions` _{(fsm_parser/mod.rs)}	✅
FSM-TEST-022	Actions before states rejected	`e710_state_after_block` _{(fsm_parser/mod.rs)}	✅
FSM-TEST-023	Duplicate domain block rejected	`e711_duplicate_domain` _{(fsm_parser/mod.rs)}	✅

Frame statement syntax (§3.6)

ID	Title	Backing test(s)	Status
FSM-TEST-030	Multi-statement block with semicolons	`fsm_test_030_action_block_semicolons` _{(codegen/fsm_python.rs)} `fsm_test_030_full` _{(fsm_parser/mod.rs)}	✅
FSM-TEST-031	Multi-statement block whitespace-separated	`fsm_test_031_action_block_whitespace` _{(codegen/fsm_python.rs)}	✅
FSM-TEST-032	If/else statement	`fsm_test_032_if_else` _{(codegen/fsm_python.rs)} `action_block_if_else` _{(fsm_parser/mod.rs)}	✅
FSM-TEST-033	Bare name does not refer to domain	`e703_bare_name_not_domain` _{(fsm_validator/mod.rs)}	✅

Typing and variable scope (§4.1, §4.2)

ID	Title	Backing test(s)	Status
FSM-TEST-100	Undeclared variable read	`e703_undeclared_read` _{(fsm_validator/mod.rs)} `e704_undeclared_write` _{(fsm_validator/mod.rs)}	✅
FSM-TEST-101	Undeclared variable write	`e704_undeclared_write` _{(fsm_validator/mod.rs)}	✅
FSM-TEST-102	Type mismatch on bare-expression @@:return	—	⏸ deferred — E706 return-type mismatch — no @@fsm type system in v0.1
FSM-TEST-103	Domain field initializer references parameter	`fsm_test_103_domain_init_references_param` _{(fsm_validator/mod.rs)}	✅
FSM-TEST-104	Domain variable missing initializer	`e705_domain_field_no_initializer` _{(fsm_parser/mod.rs)}	✅
FSM-TEST-105	Parameter accessible as self.name in body	`relational_with_call_and_member` _{(fsm_parser/mod.rs)}	✅

Actions section (§3.7)

ID	Title	Backing test(s)	Status
FSM-TEST-120	Action callable from match	`fsm_test_120_action_callable` _{(codegen/fsm_python.rs)}	✅
FSM-TEST-121	Action with domain access	`fsm_test_121_action_domain_access` _{(codegen/fsm_python.rs)} `action_block_call_statement` _{(fsm_parser/mod.rs)}	✅
FSM-TEST-122	Transition in action rejected	`e712_transition_in_action_body` _{(fsm_parser/mod.rs)}	✅
FSM-TEST-123	Action callable from embedding action	`fsm_test_123_every_transition_embed` _{(codegen/fsm_python.rs)} `rust_embed_every_transition` _{(codegen/fsm_rust.rs)}	✅

Match and exhaustiveness (§4.3)

ID	Title	Backing test(s)	Status
FSM-TEST-200	Failable match without failure_branch rejected	`e701_fallible_match_without_failure_branch` _{(fsm_validator/mod.rs)}	✅
FSM-TEST-201	Unfailable match without failure_branch allowed	`e701_not_fired_for_nullable_match` _{(fsm_validator/mod.rs)}	✅
FSM-TEST-202	Explicit failure branch	`fsm_test_400_static_transitions` _{(codegen/fsm_python.rs)}	✅
FSM-TEST-203	Terminal match without transition	`fsm_test_001_minimal` _{(codegen/fsm_python.rs)}	✅

Alphabets (§6.1)

ID	Title	Backing test(s)	Status
FSM-TEST-250	Byte alphabet	`fsm_test_250_byte_alphabet` _{(fsm_regex/mod.rs)}	✅
FSM-TEST-251	Char alphabet	`e713_accepts_char_and_token` _{(fsm_validator/mod.rs)}	✅
FSM-TEST-252	Char alphabet rejects byte escape	`fsm_test_252_char_rejects_byte_escape` _{(fsm_regex/mod.rs)}	✅
FSM-TEST-253	Token alphabet	`fsm_test_253_token_alphabet` _{(codegen/fsm_python.rs)} `e713_accepts_char_and_token` _{(fsm_validator/mod.rs)}	✅
FSM-TEST-254	Token alphabet rejects character class	`fsm_test_254_token_rejects_char_class` _{(fsm_regex/mod.rs)}	✅

Regex dialect (§6)

ID	Title	Backing test(s)	Status
FSM-TEST-300	Backreference rejected	`fsm_test_300_backreference_rejected` _{(fsm_regex/mod.rs)}	✅
FSM-TEST-301	Recursion rejected	`fsm_test_301_recursion_rejected` _{(fsm_regex/mod.rs)}	✅
FSM-TEST-302	Lookahead rejected	`fsm_test_302_lookahead_rejected` _{(fsm_regex/mod.rs)}	✅
FSM-TEST-303	Character class compiles	`fsm_test_303_character_class_compiles` _{(fsm_regex/mod.rs)}	✅
FSM-TEST-304	Alternation precedence	`fsm_test_304_alternation_precedence` _{(codegen/fsm_python.rs)}	✅
FSM-TEST-305	Bounded repetition	`fsm_test_305_bounded_repetition_compiles` _{(fsm_regex/mod.rs)}	✅
FSM-TEST-306	Greedy quantifier semantics	`fsm_test_306b_lazy_quantifier_rejected` _{(fsm_regex/mod.rs)}	✅
FSM-TEST-307	Unicode class requires opt-in	`e720_unicode_class_requires_optin` _{(fsm_validator/mod.rs)} `fsm_unicode_class` _{(codegen/fsm_python.rs)}	✅
FSM-TEST-309	Escaped slash literal	`regex_escaped_slash` _{(fsm_parser/mod.rs)}	✅
FSM-TEST-310	Empty regex rejected	`rejects_empty_with_e723` _{(fsm_regex/mod.rs)}	✅
FSM-TEST-311	DFA size limit	`e721_when_dfa_exceeds_limit` _{(fsm_regex/mod.rs)}	✅
FSM-TEST-312	Anchors	`fsm_test_312_start_anchor` _{(codegen/fsm_python.rs)} `rust_start_anchor` _{(codegen/fsm_rust.rs)}	✅
FSM-TEST-313	Interior anchor (Pike VM)	`interior_anchor_runs_on_pike_vm` _{(codegen/fsm_python.rs)} `rust_interior_anchor_runs_on_pike_vm` _{(codegen/fsm_rust.rs)}	✅
FSM-TEST-314	Word boundary on char (Pike VM)	`word_boundary_runs_on_pike_vm` _{(codegen/fsm_python.rs)} `rust_word_boundary_runs_on_pike_vm` _{(codegen/fsm_rust.rs)}	✅
FSM-TEST-315	Inline flags `(?i)`/`(?s)`/`(?m)`	`inline_flag_caseless`/`inline_flag_dotall`/`inline_flag_multiline`/`inline_flag_scoped` _{(codegen/fsm_python.rs)} `rust_inline_flags` _{(codegen/fsm_rust.rs)} `inline_flag_*` _{(fsm_regex/parser.rs)}	✅

Transitions and targets (§3.5.4, §4.4)

ID	Title	Backing test(s)	Status
FSM-TEST-400	Static transition	`fsm_test_400_static_transitions` _{(codegen/fsm_python.rs)} `states_and_transitions` _{(fsm_parser/mod.rs)}	✅
FSM-TEST-401	Stage-address transition target	`fsm_test_401_stage_ref_target` _{(codegen/fsm_python.rs)} `stage_ref_transition_target` _{(fsm_parser/mod.rs)}	✅
FSM-TEST-402	Conditional target	`fsm_test_402_conditional_target` _{(codegen/fsm_python.rs)} `rust_conditional_target` _{(codegen/fsm_rust.rs)}	✅
FSM-TEST-403	Reference to undeclared state	`e731_undeclared_state` _{(fsm_validator/mod.rs)}	✅
FSM-TEST-404	Reference to undeclared stage	`e732_undeclared_stage` _{(fsm_validator/mod.rs)}	✅
FSM-TEST-405	Conditional with no matching condition warns	`w701_conditional_without_failure` _{(fsm_validator/mod.rs)}	✅
FSM-TEST-406	Missing `when` guard on cond_alt rejected	`conditional_missing_when_errors` _{(fsm_parser/mod.rs)}	✅
FSM-TEST-407	Constant-true `when` guard warns	`w705_constant_true_when` _{(fsm_validator/mod.rs)}	✅

Runtime semantics (§5)

ID	Title	Backing test(s)	Status
FSM-TEST-500	Construction with full match	`fsm_test_006_transitions` _{(codegen/fsm_python.rs)}	✅
FSM-TEST-501	Construction with no match	`fsm_test_002_matched_builtin` _{(codegen/fsm_python.rs)}	✅
FSM-TEST-502	Cursor advances on match	`fsm_test_007_capture` _{(codegen/fsm_python.rs)}	✅
FSM-TEST-503	Stage capture exposes matched bytes	`fsm_test_007_capture` _{(codegen/fsm_python.rs)}	✅
FSM-TEST-504	Input parameter accessible as self.	`fsm_test_005_self_text` _{(codegen/fsm_python.rs)}	✅

Embedding actions (§3.5.5)

ID	Title	Backing test(s)	Status
FSM-TEST-600	Entry and per-element actions	`embed_start_captures_entry_cursor` _{(codegen/fsm_python.rs)}	✅
FSM-TEST-601	Final-state action	`embed_accept_fires_on_accepting_states` _{(codegen/fsm_python.rs)}	✅
FSM-TEST-602	EOF action	`fsm_test_602_eof_action` _{(codegen/fsm_python.rs)}	✅
FSM-TEST-603	Leave-final action	`fsm_test_603_leave_final_action` _{(codegen/fsm_python.rs)} `rust_embed_leave_final` _{(codegen/fsm_rust.rs)}	✅

Composition (§8)

ID	Title	Backing test(s)	Status
FSM-TEST-700	Mode C composition	`fsm_mode_c_call_out` _{(pipeline/compiler.rs)} `fsm_mode_c_chained` _{(pipeline/compiler.rs)}	✅
FSM-TEST-701	Mode C bytes-and-return	`fsm_mode_c_call_out` _{(pipeline/compiler.rs)}	✅
FSM-TEST-702	Mode C type mismatch	—	⏸ deferred — E706 Mode C type mismatch — no @@fsm type system in v0.1
FSM-TEST-703	Mode C alphabet mismatch	`e731_mode_c_alphabet_mismatch` _{(fsm_validator/mod.rs)}	✅
FSM-TEST-704	Mode C dynamic dispatch rejected	`e732_mode_c_dynamic_dispatch` _{(fsm_validator/mod.rs)}	✅

Edge cases

ID	Title	Backing test(s)	Status
FSM-TEST-1000	Empty input	`fsm_test_001_minimal` _{(codegen/fsm_python.rs)}	✅
FSM-TEST-1001	Input exactly matching	`fsm_test_001_minimal` _{(codegen/fsm_python.rs)}	✅
FSM-TEST-1002	Input longer than match	`fsm_test_007_capture` _{(codegen/fsm_python.rs)}	✅
FSM-TEST-1003	Input strictly prefix of match	`fsm_test_1003_prefix_of_match_rejected` _{(codegen/fsm_python.rs)}	✅
FSM-TEST-1004	Anchored match with leading non-match	`fsm_test_312_start_anchor` _{(codegen/fsm_python.rs)}	✅
FSM-TEST-1005	Zero-length match	`fsm_test_1005_zero_length_match` _{(codegen/fsm_python.rs)}	✅
FSM-TEST-1006	@@:matched before any stage completes	`fsm_test_1006_matched_before_stage` _{(codegen/fsm_python.rs)}	✅

Additional diagnostic coverage

ID	Title	Backing test(s)	Status
FSM-TEST-1100	Malformed declaration (missing fsm name)	`fsm_test_1100_missing_name` _{(fsm_parser/mod.rs)} `generic_error_is_e700` _{(fsm_parser/mod.rs)}	✅
FSM-TEST-1101	Malformed declaration (missing body braces)	`fsm_test_1101_missing_body_braces` _{(fsm_parser/mod.rs)} `generic_error_is_e700` _{(fsm_parser/mod.rs)}	✅
FSM-TEST-1102	Stage label collision within a state	`e730_duplicate_stage_label` _{(fsm_validator/mod.rs)}	✅
FSM-TEST-1103	Unused parameter warning	`w702_unused_parameter` _{(fsm_validator/mod.rs)}	✅
FSM-TEST-1104	Unused domain variable warning	`w703_unused_domain_field` _{(fsm_validator/mod.rs)}	✅
FSM-TEST-1105	DFA size approaching limit warning	`(module reference)` _{(fsm_regex/size_check.rs)}	✅

Deferrals (tracked in the enforcement allowlist)

These 2 IDs have no backing test by design; each is an explicit, justified entry in the allowlist so it stays visible rather than silently uncovered. Both require an @@fsm-level type system, which v0.1 deliberately omits (type errors are deferred to the host language’s compiler).

ID	Reason
FSM-TEST-102	E706 return-type mismatch — no @@fsm type system in v0.1
FSM-TEST-702	E706 Mode C type mismatch — no @@fsm type system in v0.1

Running the tests

cargo test --lib fsm                        # all @@fsm unit + execution tests (500)
cargo test --test fsm_conformance_coverage  # the coverage guard
cargo test                                  # full suite (1259 tests)

RFC-0042 @@fsm — Conformance Test Coverage