fix: right bound node lookups BED-7469

[urangel]

Single step and expansion relationship patterns are updated to handle bindings associated with the right node.
Test cases that reflect the patterns in the reported issues have been added.

The okta example in the ticket:

Simplied BP-1590 pattern:

Shortest path, gh issue/BP-2257:

Summary by CodeRabbit

Release Notes

• Bug Fixes

  • Fixed pattern matching for queries with bound node references, improving SQL translation accuracy
  • Enhanced support for complex multi-part path patterns and pattern expansion scenarios
  • Corrected shortest path query generation to properly resolve node and edge bindings

• Documentation

  • Removed documentation of previously identified pattern binding defect

[coderabbitai]

Walkthrough

The changes fix pattern matching translation for right-node-bound scenarios and shortest-path queries by introducing a previousValidFrame mechanism in the expansion builder, updating test case SQL output to reflect corrected recursive CTE generation, and removing documentation of a now-fixed defect.

Changes

Cohort / File(s)	Summary
Documentation cypher/Cypher Syntax Support.md	Removed documentation describing a known defect pattern and its associated SQL translation error.
Test Case Updates cypher/models/pgsql/test/translation_cases/multipart.sql, pattern_binding.sql, pattern_expansion.sql, shortest_paths.sql	Updated generated SQL test expectations for recursive CTE queries: modified recursive step FROM clauses and join correlation, adjusted node-kind filter predicates, and added new pattern-binding test cases.
Core Translation Logic cypher/models/pgsql/translate/expansion.go	Refactored ExpansionBuilder to introduce previousValidFrame field for binding projection queries to prior materialized frames; changed constraint checking from PrimerNodeConstraints to PrimerNodeJoinCondition; updated shortest-path projection query construction and constraint rewriting semantics.
Pattern & Traversal Translation cypher/models/pgsql/translate/pattern.go, traversal.go	Added derivation and assignment of previousValidFrame in shortest-path expansion pattern building; implemented RightNodeBound handling in traversal root builder with proper FROM clause and join construction.

Estimated code review effort

🎯 4 (Complex) | ⏱️ ~60 minutes

Poem

🐰 With frames now bound and traversals right,
Shortest paths shine with corrected light,
Recursive steps now dance in place,
Right-node bounds find their proper space,
A defect fixed, the syntax soars,
Pattern matching opens new doors! 🌟

🚥 Pre-merge checks | ✅ 2 | ❌ 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%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately summarizes the primary change: handling right-bound node lookups in relationship patterns, which is the main focus across multiple translation and pattern matching files.
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.

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✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch BED-7469

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[urangel]

The pattern noted here (and a few related patterns) has been fixed though it is unclear whether all possible occurrences of right-hand bound node lookups have been addressed.

Is removing this documentation premature?

[coderabbitai]

Caution

Some comments are outside the diff and can’t be posted inline due to platform limitations.

⚠️ Outside diff range comments (1)

cypher/models/pgsql/translate/expansion.go (1)

128-139: ⚠️ Potential issue | 🔴 Critical

Fix line 401: change condition check to PrimerNodeJoinCondition.

Lines 128 and 300 correctly check if expansionModel.PrimerNodeJoinCondition != nil before adding the primer node join, but line 401 in prepareBackwardFrontRecursiveQuery incorrectly checks if expansionModel.PrimerNodeConstraints != nil. Since the join uses s.traversalStep.Expansion.PrimerNodeJoinCondition as its constraint, the condition should match the field being used. Change line 401 to check PrimerNodeJoinCondition for consistency with the other two primer query functions and to ensure the join is added based on actual join condition presence rather than filter constraint presence.

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In `@cypher/models/pgsql/translate/expansion.go` around lines 128 - 139, The
prepareBackwardFrontRecursiveQuery function incorrectly checks
expansionModel.PrimerNodeConstraints before adding the primer node join; update
that condition to check expansionModel.PrimerNodeJoinCondition so it matches the
join's Constraint usage (s.traversalStep.Expansion.PrimerNodeJoinCondition) and
aligns with the checks in the other primer query functions (see the similar
blocks that use expansionModel.PrimerNodeJoinCondition to append to
nextQueryFrom.Joins).

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Outside diff comments:
In `@cypher/models/pgsql/translate/expansion.go`:
- Around line 128-139: The prepareBackwardFrontRecursiveQuery function
incorrectly checks expansionModel.PrimerNodeConstraints before adding the primer
node join; update that condition to check expansionModel.PrimerNodeJoinCondition
so it matches the join's Constraint usage
(s.traversalStep.Expansion.PrimerNodeJoinCondition) and aligns with the checks
in the other primer query functions (see the similar blocks that use
expansionModel.PrimerNodeJoinCondition to append to nextQueryFrom.Joins).

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: d44fbecb-98c0-40f5-8d9b-a79b820a07bd

📥 Commits

Reviewing files that changed from the base of the PR and between 21473e6 and 194bdd2.

📒 Files selected for processing (8)

• cypher/Cypher Syntax Support.md
• cypher/models/pgsql/test/translation_cases/multipart.sql
• cypher/models/pgsql/test/translation_cases/pattern_binding.sql
• cypher/models/pgsql/test/translation_cases/pattern_expansion.sql
• cypher/models/pgsql/test/translation_cases/shortest_paths.sql
• cypher/models/pgsql/translate/expansion.go
• cypher/models/pgsql/translate/pattern.go
• cypher/models/pgsql/translate/traversal.go

💤 Files with no reviewable changes (1)

• cypher/Cypher Syntax Support.md