testing-guidelines

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UpdatedJuly 29, 2026 at 11:23

Opinionated language-agnostic test-admission and sans-I/O unit-testing rules. Use when proposing, writing, reviewing, or deleting tests; deciding whether behavior is project-owned; evaluating wrapper, schema, ORM, framework, mock, or third-party-library tests; or separating pure business policy from wiring and I/O.

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Casper-Studios

Casper-Studios/casper-marketplace

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Software Quality Assurance Analysts and TestersComputer and Mathematical Occupations·SOC 15-1253

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SKILL.md

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name	testing-guidelines
description	Opinionated language-agnostic test-admission and sans-I/O unit-testing rules. Use when proposing, writing, reviewing, or deleting tests; deciding whether behavior is project-owned; evaluating wrapper, schema, ORM, framework, mock, or third-party-library tests; or separating pure business policy from wiring and I/O.
license	MPL-2.0
metadata	{"author":"Basti Ortiz <ortiz@bastidood.dev>","source":"https://github.com/BastiDood/skills"}

Testing Guidelines

This skill treats tests as protection for project-owned behavior, not as a coverage ritual. It favors cheap sans-I/O tests and rejects tests that merely restate third-party libraries or transparent wiring.

Test Admission

Test behavior that the project owns. Assume third-party libraries are correct and already tested.

Add a test only when it can fail because project-owned behavior is wrong.

Project-owned behavior includes:

Business rules and calculations.
State-machine transitions and exhaustive decisions.
Transformations that add domain meaning.
Selection, retry, fallback, caching, and persistence policy.
Error translation that adds a stable project contract.

Do not add a test when the implementation only forwards values to a dependency and returns its result unchanged.

Existing-Test Review

Delete a test when it only:

Repeats third-party documentation.
Asserts schema-library mechanics.
Verifies a one-to-one forwarding wrapper.
Asserts mock configuration.
Checks getters, constructors, or field assignment without behavior.
Exercises framework plumbing without a project-owned contract.

Do not preserve a useless test for coverage. Coverage is evidence of execution, not evidence of meaningful verification.

References

Read as many linked references as are relevant to the current task before writing, approving, or retaining tests.

Do not claim ownership of documented library behavior; treat third-party dependencies as already verified.
Exclude tests that only prove delegation through transparent wrappers.
Prove project-owned policy through cheap sans-I/O tests, adding wiring coverage only for owned boundary behavior.

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name	testing-guidelines
description	Opinionated language-agnostic test-admission and sans-I/O unit-testing rules. Use when proposing, writing, reviewing, or deleting tests; deciding whether behavior is project-owned; evaluating wrapper, schema, ORM, framework, mock, or third-party-library tests; or separating pure business policy from wiring and I/O.
license	MPL-2.0
metadata	{"author":"Basti Ortiz <ortiz@bastidood.dev>","source":"https://github.com/BastiDood/skills"}

Testing Guidelines

Test Admission

Test behavior that the project owns. Assume third-party libraries are correct and already tested.

Add a test only when it can fail because project-owned behavior is wrong.

Project-owned behavior includes:

Business rules and calculations.
State-machine transitions and exhaustive decisions.
Transformations that add domain meaning.
Selection, retry, fallback, caching, and persistence policy.
Error translation that adds a stable project contract.

Do not add a test when the implementation only forwards values to a dependency and returns its result unchanged.

Existing-Test Review

Delete a test when it only:

Repeats third-party documentation.
Asserts schema-library mechanics.
Verifies a one-to-one forwarding wrapper.
Asserts mock configuration.
Checks getters, constructors, or field assignment without behavior.
Exercises framework plumbing without a project-owned contract.

Do not preserve a useless test for coverage. Coverage is evidence of execution, not evidence of meaningful verification.

References

Read as many linked references as are relevant to the current task before writing, approving, or retaining tests.

Do not claim ownership of documented library behavior; treat third-party dependencies as already verified.
Exclude tests that only prove delegation through transparent wrappers.
Prove project-owned policy through cheap sans-I/O tests, adding wiring coverage only for owned boundary behavior.