Write independent test methods
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.
Keep your working files in your own notebook or software. Save a private description, checklist, and work link in My Proof.
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
test_light calls parcel_fee(0.5). test_boundaries checks other cases. Run python -m unittest -v from the practice folder.
A unittest.TestCase method beginning with test is discovered by the runner. Each test should make its own needed state; relying on another test to run first creates fragile order-dependent evidence.
Write independent test methods — original worked practice
A unittest.TestCase method beginning with test is discovered by the runner. Each test should make its own needed state; relying on another test to run first creates fragile order-dependent evidence.
test_light calls parcel_fee(0.5). test_boundaries checks other cases. Run python -m unittest -v from the practice folder.
1. Step 1
Read the TestCase subclass and test names.
You should see: The runner discovers five test methods in the supplied file.
This keeps the rule and its observable result together.
2. Step 2
Run the light-weight assertion alone.
You should see: It passes without any earlier test setup.
This keeps the rule and its observable result together.
3. Step 3
Run the whole test file.
You should see: Each method can be executed independently.
This keeps the rule and its observable result together.
4. Step 4
Record test names, run command and status.
You should see: An executable unit-test record with independent cases.
This keeps the rule and its observable result together.
What to finish
An executable unit-test record with independent cases.
Watch for this
Sharing mutable state across test methods and accidentally relying on execution order.
How can I tell I understand it?
Explain and demonstrate the required distinction: A unittest.TestCase method beginning with test is discovered by the runner. Each test should make its own needed state; relying on another test to run first creates fragile order-dependent evidence. 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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