EIR VM: assert-eq uses structural equality, not handle identity

[ecto]

What

Built::AssertEq in the EIR VM compared raw Val handles, so [assert-eq {:a 1} {:a 1}] failed on two separately-allocated but structurally equal values (maps, vecs, non-interned strings). It now routes through the same val_eq the = builtin already uses.

Why

Found while writing law-checking tests for a monoid-action sketch: assert-eq on two identical map literals reported {:log "a" :val "b"} != {:log "a" :val "b"}. Any loon test asserting on collections was silently un-passable on the EIR VM.

Notes for review

• One-line fix in vm.rs plus a backend-parity regression test (assert-eq-structural, order-independent map keys).
• cargo test --workspace is green.
• A related but separate checker bug (E0200 unifying a record with () on map destructures) was spun off into its own task.

🤖 Generated with Claude Code

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Project	Deployment	Actions	Updated (UTC)
loon	Ready	Preview, Comment	Jul 14, 2026 1:54pm

[chojiai]

Choji review — Looks good

Correct one-line fix: routing Built::AssertEq through val_eq makes it consistent with the = builtin, and the regression test covers the exact failure mode (separately-allocated, order-independent maps with a string value). No defects found.

No findings — looks good.

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Verified by Choji

Choji ran your change live — checks passed.

1 check.

Claim	Result	Evidence
cargo check	Verified	exit 0 · 643s

The ticket asked for assert-eq in the EIR VM to use structural equality instead of raw handle identity; the one-line fix in vm.rs routes the comparison through val_eq, and the new assert-eq-structural backend-parity test exercises exactly that case (two separately-allocated but equal maps with order-independent keys). No live preview was run since this is a compiler/VM backend change, but cargo check passed (exit 0). No issues observed.

No issues found in the running app.

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Reviewed 94aa5c9 · Rate findings · Choji updates this comment as you push