iss-gq-undirected-traversal, the Expand-internal design (no plan-level
Union; unblocked from iss-744/579): the grammar gains an undirected_edge
alternative in the traversal rule (angle brackets are collision-free —
comparisons live in the structurally separate filter production), the
AST Traversal carries `undirected`, Direction gains `Both`, and
typecheck resolves undirected patterns to Both after the new T22 rule:
undirected requires a same-endpoint-type edge (an asymmetric edge is
well-typed in at most one orientation, so the form is rejected with
guidance to use the directional pattern). Lowering passes Both through;
the reverse-expand orientation flip is a no-op for a symmetric
traversal. Bounds ({min,max}) and not{} compose unchanged.
Direction has no serde derives and IR never crosses a wire — no
compatibility surface. Parser/typecheck tests cover the bare, bounded,
inside-not forms, Both resolution on Knows (Person->Person), and the
T22 rejection on WorksAt (Person->Company).
typecheck.rs, schema/parser.rs, and query/parser.rs each had
~1000-line inline `mod tests` blocks that overshadowed the production
code in the file. Move each to a sibling `*_tests.rs` using
`#[path = "..."] mod tests;`.
- typecheck.rs: 2865 → 1708 lines; typecheck_tests.rs: 1156 lines
- schema/parser.rs: 1950 → 994 lines; parser_tests.rs: 955 lines
- query/parser.rs: 1737 → 803 lines; parser_tests.rs: 933 lines
No visibility change — the sibling module still has `use super::*`
access to crate-privates. No semantic edits beyond de-indenting by
4 spaces (mechanical). All 229 compiler tests green, identical
count to before.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
