AI for Python coding: test the edge case before trusting the function
Evidence date: 2026-10-07

Decision criteria
Current feature allowance, editor support and repository policy.

Editorial evaluation scenario
Fictional function averages a list. Supplied inputs are [2,4,6] and an empty list; empty input should raise ValueError.
Specify valid inputs, the empty-input policy and at least one result you can compute by hand. Run proposed code in a controlled environment before describing it as tested.
Current feature allowance, editor support and repository policy.

Input / draft / final edit
Fictional function averages a list. Supplied inputs are [2,4,6] and an empty list; empty input should raise ValueError.
Return sum(values)/len(values) with no empty-input check.
Check for empty input and raise ValueError. For [2,4,6], compute 12/3=4. Keep both acceptance cases in the test plan.

Before buying
GitHub Docs
Documented: GitHub documents Copilot plan differences and usage allowances.
Check: Current feature allowance, editor support and repository policy.
Manual or conventional route
Documented: Use a small conventional function when the task has a fixed specification and no ambiguous requirements.
Check: Editorial workflow advice; this is not a measured comparison or vendor performance claim.

Official sources
https://docs.github.com/en/copilot/get-started/plans

Record your own test: selected plan, date, input, output, corrections, export and total cost. This sheet does not claim a vendor test.