PromptVault
CodingProIntermediate

Property-based tests shaped around real invariants

For engineers turning domain rules into cases that shrink to useful counterexamples.

Works with
  • Cursor
  • GitHub Copilot
  • Codex
The prompt118 words · 4 blanks

Produce a property-based test checklist for [language_tooling] from [invariant_brief], containing exactly [case_count]…

The full prompt is in the app

Included with PromptVault Pro. Fill in the blanks there, then copy it into Cursor.

What you fill in

  • Language and test tool[language_tooling]ExampleTypeScript with fast-check
  • Domain invariants[invariant_brief]ExampleCart totals never go negative; applying the same coupon twice is idempotent
  • Property count[case_count]Example8
  • Generator branch limit[generator_budget]Example12

How to use it

  1. 1Open it in PromptVault. Find it in Coding, or search for “Property-based tests shaped around real invariants”.
  2. 2Fill in the 4 blanks. language and test tool, domain invariants, property count and generator branch limit — the only things the prompt cannot know.
  3. 3Copy and paste it into Cursor. It also works with GitHub Copilot and Codex.

About this prompt

“Property-based tests shaped around real invariants” is a intermediate coding prompt. For engineers turning domain rules into cases that shrink to useful counterexamples. It is 118 words long and written to get a usable answer on the first message, in Cursor, GitHub Copilot and Codex or any other chat assistant. Good for: testing, checklist, first draft and deep dive. Like every prompt in PromptVault, it was written and edited in-house, and it works offline once the app is installed.

More coding prompts

All 120 in Coding