Parameterize boundary cases
See this course’s project requirements
A runnable automated test suite for an original parcel-price module with boundary cases, isolated fixtures, failure evidence and a repaired regression.
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What to include
- A price assertion table with independent expected values.
- An executable unit-test record with independent cases.
- A labeled boundary-test table across both price tiers.
- A rejection suite with a passing valid boundary comparison.
- An isolated file test with declared automatic cleanup.
- A failing-then-passing regression record with source and run instructions.
Review and revise
Use these criteria to check your work and choose what to improve.
- The implementation or declared simulation follows the supplied contract and retains inspectable original inputs.
- Normal, boundary and rejected cases are recorded with expected versus observed results.
- The changed case has a correct explanation and does not rely on hidden state.
- The project includes source, outputs, instructions and honest tool, privacy and verification limits.
Want more background?
The idea in everyday life
Boundary table:1→4,1.01→7,5→7. Invalid 5.01 belongs in the rejection table.
A boundary separates rules, so test both sides and the exact boundary. subTest labels cases within a test without hiding which input failed.
Parameterize boundary cases — original worked practice
A boundary separates rules, so test both sides and the exact boundary. subTest labels cases within a test without hiding which input failed.
Boundary table:1→4,1.01→7,5→7. Invalid 5.01 belongs in the rejection table.
1. Step 1
Write values just below, at and just above 1.
You should see: 0.99→4,1→4,1.01→7.
This keeps the rule and its observable result together.
2. Step 2
Read the subTest(weight=weight) label.
You should see: A failure identifies the case weight.
This keeps the rule and its observable result together.
3. Step 3
Add the upper accepted boundary 5.
You should see: 5→7.
This keeps the rule and its observable result together.
4. Step 4
Run the table and keep expected/observed values.
You should see: A labeled boundary-test table across both price tiers.
This keeps the rule and its observable result together.
What to finish
A labeled boundary-test table across both price tiers.
Watch for this
Skipping the exact one-kilogram boundary where the stated fee changes.
How can I tell I understand it?
Explain and demonstrate the required distinction: A boundary separates rules, so test both sides and the exact boundary. subTest labels cases within a test without hiding which input failed. Show a changed input and the expected result without weakening this contract.
Quick knowledge check
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Source & access notes · checked 2026-10-01
Relevant documented module/API behavior inspected during expansion authoring; actual execution evidence is recorded separately. No grant eligibility is established.
Access: Official page retrieved with the web reader on 2026-10-01. Documentation reading does not certify execution in every native tool or browser.
Reuse: Original local practice files, fictional data, worked examples and questions. Concepts paraphrased and linked; source exercises are not copied.
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