fix(sql-contract-ts): anchor inverse relations on the owning belongsTo's referenced field

[lazerg]

Linked issue

Fixes #30214

Summary

hasOne/hasMany relations anchored their parent side on the model's primary identity no matter what the owning belongsTo on the child actually referenced. When a parent has both an id and a separate unique field that a child's belongsTo joins against, the contract builder still emitted the inverse relation's join against id, so the inverse side pointed at the wrong column whenever the two values differ for a row.

The fix looks up the owning belongsTo relation on the target model that matches the hasOne/hasMany's local field(s) and reuses its referenced field(s) as the anchor, falling back to the primary identity only when no such relation exists.

Testing performed

• pnpm --filter @internal/sql-contract-ts test
• pnpm --filter @internal/sql-contract-ts typecheck
• pnpm lint:deps

Skill update

n/a - internal only, no user-facing surface changed.

Checklist

• All commits are signed off (git commit -s) per the DCO.
• I read CONTRIBUTING.md and the change is scoped to one logical concern.
• Tests are updated.
• Skill update section above is filled in.

Notes for the reviewer

Used a conventional commit title (fix(sql-contract-ts): ...) rather than a TML-NNNN: prefix since there is no Linear ticket behind this, per the external-contributor convention in CONTRIBUTING.md.

Summary by CodeRabbit

• Bug Fixes

  • Fixed relation handling so inverse hasOne relationships use the corresponding parent-side reference field when available.
  • Improved normalization of child relationship fields before resolving parent anchors.
  • Added validation to report an error when owning relationships specify conflicting reference fields.

• Tests

  • Added coverage verifying correct parent-side anchor selection for inverse relationships.
  • Added coverage for conflicting relationship reference fields.

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Reviewing files that changed from the base of the PR and between 27763e2 and 706da05.

📒 Files selected for processing (2)

• packages/2-sql/2-authoring/contract-ts/src/contract-lowering.ts
• packages/2-sql/2-authoring/contract-ts/test/contract-lowering.runtime.test.ts

🚧 Files skipped from review as they are similar to previous changes (2)

• packages/2-sql/2-authoring/contract-ts/test/contract-lowering.runtime.test.ts
• packages/2-sql/2-authoring/contract-ts/src/contract-lowering.ts

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📝 Walkthrough

Walkthrough

The contract lowering logic now derives inverse ownership anchors from matching belongsTo relations, preserves alternate parent keys, and rejects conflicting anchors. Runtime tests cover both behaviors.

Changes

Inverse relation anchor resolution

Layer / File(s)	Summary
Resolve inverse relation anchors packages/2-sql/2-authoring/contract-ts/src/contract-lowering.ts	The resolver collects matching belongsTo relations and uses their target fields as parent anchors. It throws CONTRACT.RELATION_INVALID when matching relations disagree. It falls back to the model identity anchor when no match exists.
Validate relation anchor resolution packages/2-sql/2-authoring/contract-ts/test/contract-lowering.runtime.test.ts	Runtime tests verify alternate-key anchoring from Parent.externalKey to Child.ownerKey and rejection of conflicting target fields.

Estimated code review effort: 2 (Simple) | ~10 minutes

Merge Risk: ⚪ Minimal · up to 706da

This change corrects inverse relation anchors for alternate and composite referenced keys and rejects conflicting relation definitions. No concrete merge-blocking risk remains.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 3 functions across 2 files.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly describes the primary change: inverse relations now use the referenced field from the owning belongsTo relation as their anchor.
Linked Issues check	✅ Passed	The implementation addresses issue [#30214]. It anchors inverse relations to matching belongsTo target fields, preserves normalized referenced field tuples for composite keys, falls back to the identi…
Out of Scope Changes check	✅ Passed	The code and tests are within scope. They implement inverse relation anchor correction and validation for ambiguous belongsTo relations described in [#30214].

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Actionable comments posted: 1

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Inline comments:
In `@packages/2-sql/2-authoring/contract-ts/src/contract-lowering.ts`:
- Around line 484-499: Update resolveOwningRelationAnchorFields to collect all
matching belongsTo relations instead of returning the first match; throw
CONTRACT.RELATION_INVALID when multiple matches have different anchor fields,
and return the sole match’s normalized to fields otherwise.

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📒 Files selected for processing (2)

• packages/2-sql/2-authoring/contract-ts/src/contract-lowering.ts
• packages/2-sql/2-authoring/contract-ts/test/contract-lowering.runtime.test.ts

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[SevInf]

Hi @lazerg
Could you add an integration test that demonstrate the problem going from public API? You can see a bunch of integration tests in test/integration package, let me know if you need help

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commit: 706da05

[lazerg]

Closing this. The linked issue (#30214) got closed as not planned — the reporter flagged the whole batch of Codex-generated reports as possibly spam rather than real bugs.