2026-04-07

Matrix Widget: Formula Builder Suggestions Context

Enhanced the formula builder dropdown in the matrix to properly differentiate column suggestions when groups are used.

Decisions & Solutions

• Contextual Transparency: In getMatrixColReferenceFields, check if useColumnGroups is enabled. If so, iteratively extract and merge the group label with the column label into the dropdown display string (Col n — Group Label.Column Label). This ensures users can discern same-named columns belonging to different groups.

Matrix Formula Batch API — N HTTP calls -> 2

Optimized the matrix formula evaluation pipeline by implementing a batch API, reducing the number of backend requests from N*M+N down to a constant 2 (or 1+N where N is formula rows).

Decisions & Solutions

• Batch Execution: Introduced POST /api/formula/evaluate-batch on the backend to evaluate multiple expressions in a single request.
• Expression Deduplication: Implemented a per-request Map<string, ParsedExpr> cache on the backend. This ensures that identical expressions (e.g., the same formula column across 20 rows) are parsed only once.
• Frontend Refactoring: Refactored evaluateFormulaColumn() and evaluateSingleFormulaRow$() in MatrixComponent to collect payloads and dispatch a single evaluateFormulaBatch() call instead of parallel forkJoin individual calls.
• Sequential Safety: Maintained concatMap sequential ordering for formula rows to ensure cascading references (e.g., Row 5 referencing Row 3) remain accurate.
• Resilience: Maintained per-item try/catch on the backend so one malformed expression doesn't break the entire batch.