Calculation code review checklist

Expert

Apply a systematic checklist to review FileMaker calculations for correctness, performance, edge cases, and maintainability before shipping.

What you'll learn

The seven categories of a FileMaker calculation review
Which edge cases most commonly cause production bugs
How to verify performance characteristics before deploying
How to leave reviewable notes in a calculation for future maintainers

Most calculation bugs are caught not during writing but during review -- a second pass that tests assumptions, checks edge cases, and asks whether the calculation will still work after the data grows or the schema evolves. A structured checklist ensures no review is skipped and documents why each decision was made.

1/5

Category 1: Correctness -- does it do what is intended?

Test the calculation against representative values including empty inputs, zero, negative numbers, and boundary conditions.

FileMaker Script

// Test matrix for a "days until due" calculation:
// Normal case:    DueDate = today + 30  -> expect 30
// Zero case:      DueDate = today       -> expect 0
// Overdue:        DueDate = today - 5  -> expect -5
// Empty DueDate:  DueDate = ""          -> expect "" or a safe fallback
// Empty Today:    unlikely but test anyway

Let ( d = DueDate ;
  If ( IsEmpty ( d ) ; "" ; d - Get ( CurrentDate ) )
)
// Guards empty input, handles negative (overdue) correctly

Designing calculation field libraries Back to Calculations