fix(policy): compact relation subquery aliases to avoid PostgreSQL identifier truncation

[ymc9]

Summary

Follow-up to #2845, addressing a CodeRabbit finding.

Relation subquery aliases in the policy expression transformer were built as ${field}$${counter} without the temp alias prefix, so the executor's existing TempAliasTransformer left them untouched. On PostgreSQL a relation field name of 62+ chars made every alias derived from it truncate to the same 63-byte identifier, producing table name ... specified more than once or, across nested subqueries, re-introducing the self-relation shadowing that #2845 fixed.

newRelationAlias now routes through QueryUtils.tmpAlias(), so the existing transformer compacts the aliases (or shortens only over-long ones when useCompactAliasNames is off). No new shortening scheme is introduced.

Tests

Added a PostgreSQL regression test in tests/e2e/orm/policy/self-relation.test.ts with a 70-char self many-to-many relation field and a nested collection predicate, run with useCompactAliasNames: false to exercise the length guard. It fails before this change with the truncation error and passes after.

Ran tests/e2e/orm/policy, tests/regression, and packages/orm suites on SQLite, plus policy plugin lint.

🤖 Generated with Claude Code

Summary by CodeRabbit

• Bug Fixes

  • Prevented long relation aliases from being incorrectly truncated into identical identifiers in PostgreSQL queries.
  • Improved reliability for multi-hop self-relation filters involving lengthy field names.

• Tests

  • Added coverage for long-name self-relations and two-hop predicates in PostgreSQL.

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ℹ️ Recent review info

⚙️ Run configuration

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Run ID: 6cf4adc6-d0de-43cd-a45a-e9ff2e8eba89

📥 Commits

Reviewing files that changed from the base of the PR and between 0efd7ae and 9040abf.

📒 Files selected for processing (2)

• packages/plugins/policy/src/expression-transformer.ts
• tests/e2e/orm/policy/self-relation.test.ts

🚧 Files skipped from review as they are similar to previous changes (1)

• packages/plugins/policy/src/expression-transformer.ts

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📝 Walkthrough

Walkthrough

The policy transformer now marks generated relation aliases as temporary. New PostgreSQL end-to-end tests cover self-relations, nested predicates, tenant enforcement, many-to-many access, and long relation names.

Changes

Relation alias isolation

Layer / File(s)	Summary
Temporary relation alias generation packages/plugins/policy/src/expression-transformer.ts	newRelationAlias wraps generated aliases with QueryUtils.tmpAlias so the query executor can shorten long aliases.
Self-relation policy validation tests/e2e/orm/policy/self-relation.test.ts	End-to-end tests cover tenant-bound self-relation reads and writes, nested predicates, multi-hop access, many-to-many relations, and long PostgreSQL identifiers.

Priority: ⬇️ Low

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

Change: Bug fix

Merge Risk: ⚪ Minimal · up to 9040a

No concrete merge-blocking defect was identified in the changed alias handling or its regression coverage.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check. Docstring coverage is scoped to functions touched by this diff. Analyzed 0 functions across 2…
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and concisely describes the main change: compacting policy relation subquery aliases to prevent PostgreSQL identifier truncation and collisions.

✨ Finishing Touches

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