Regression Test

You might say

After changing tax rules, rerun payment, coupons, and order confirmation as well as the new rule to ensure working checkout was not broken.

Regression testing checks that a change has not broken functionality that previously worked.After tax changes, rerun payment, coupons, and confirmation; after dependency upgrades, rerun critical pages. It selects old capabilities the change could affect, not only the new request. A new feature working does not prove no regression.

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Test Case

Regression Test

Which old flows rerun after a tax rule changes

shop.local/checkout/order-778Baseline

Order checkout

Travel backpack¥100

Coupon SUMMER8−¥8

Tax¥8

Keep the pre-change baseline so later differences can be separated into intended changes and regressions.

How regression selects scope

Find old cases from the impact surface: Because tax participates in order total, rerun coupons, payment amount, and confirmation—not merely the new rate. Scope comes from data and flow connections, not mechanically rerunning everything.

Use prior expectations to catch surprises: A checkout that used to complete, an amount that used to be correct, or an old clear error that changes after this edit is a regression worth addressing. Compare results before and after.

Quick checkChoose the best answer

The team changed only coupon calculation, but the total also affects payment and order confirmation. Which set belongs in regression?

Existing coupon, payment-total, and order-confirmation casesOnly check that the new coupon displaysOnly check profile-avatar upload

You can say this to an AI Agent

After changing tax and coupon rules, run regression by impact: retest existing coupons, payment totals, and order confirmation. Do not only report the new rule passing; list the actual result for each older path.

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