[kotomuch]

Summary

Extends the go_keyword_names pass (HYB-E1002, Row 13 BUILDABLE) to three declaration surfaces that previously bypassed the default/none detector (fixes #4190).

Root Cause & Defect

compiler/crates/hy-check/src/go_keyword_names.rs enforced keyword-name hygiene on locals, params, receivers, structs, aliases, consts, fields, loop vars, select/match bindings — but missed:

1. Decl::Enum skipped entirely (matched to {} alongside Import): enum default { … }, variant names (enum state { default }), and payload types carrying default/none passed check with 0 diagnostics, then failed hyb build (hy-emit spells enum names/variants verbatim).
2. Dotted associated-function names: self.kw_name(&f.name, …) compared the full dotted string ("box.default", "default.build") against the keyword — never equal, so associated fns named default/none in either segment bypassed the check.
3. Decl::Import unhandled: non-Rust imports register the trailing path segment as the Go package identifier (lib.rs rsplit; emission root.Member() in hy-emit), so import "x/default" produced unparseable Go.

Changes

• Decl::Enum: enum name ("enum"), each variant name ("enum variant"), payload types via kw_type.
• Decl::Fn: split f.name on . and check each segment (dotted receiver-associated names).
• Decl::Import: for !path.starts_with("rust/") check the trailing segment ("package import"); rust/ crates keep their separate registration rule (prefix-rooted, not trailing-segment).
• Doc comment updated (enum variants are no longer left alone).

Tests

New compiler/crates/hy-check/tests/go_keyword_enum_dotted_import_names.rs (harness mirrors go_keyword_default_names.rs):

• 6 negative tests: enum/variant/none variants, payload traversal (fn param + struct field through enum payload), dotted box.default/box.none/default.build, import aliases (x/default, y/none, bare default);
• 2 positive controls: dotted clean segment (box.defaults), rust/ import, clean alias (x/fallback), plain fmt.

Test names listed rather than runner counts: no local cargo on this machine; fork CI and your battery are the verification loop — happy to fix anything they flag.

Cost honesty

What breaks: programs declaring enums/dotted-fns/imports named default or none — previously accepted, then failing go build (Row 13 violations, exactly the class this pass closes). Existing valid programs unaffected (positive controls pin rust/ imports and clean names).

Disclosure: Authored by an autonomous coding agent; the account owner has reviewed the patch and stands behind every line.