F6 · Deriving Test Scenarios from: Everything you learned in F1-F5 (the contract concept, auto-generation, Try it out, schema reading, contract defects) merges into ONE SKILL: de
Everything you learned in F1-F5 (the contract concept, auto-generation, Try it out, schema reading, contract defects) merges into ONE SKILL: deriving a SYSTEMATIC test scenario CHECKLIST from a spec file. This is like extracting an **inspection checklist** from an architectural blueprint: an electrician looks at the blueprint and checks ONE BY ONE that "every outlet is in the right place, every wire is the right gauge" — they do not wander randomly. So why is this BETTER than "testing randomly"? Because every `required`/`type`/`enum` constraint in the schema GUARANTEES a test scenario (F4), and every endpoint's 2xx/4xx/5xx possibilities are KNOWN (A5) — combining the two, you move from "test whatever comes to mind" to a checklist of "systematically try every case the spec ALLOWS and FORBIDS". The Java equivalent is a "contract test" suite that tests all implementations of an `interface` — every implementation must satisfy the SAME behavior contract. For QA, this is the peak of GROUP F: the spec is no longer just a document you READ, it is source material you PLAN tests from.
From a Schema to a Checklist
🎬 6 Test Scenarios Are Born from One Schema
Happy path: 1 scenario
Negative: 5 scenarios
The tester looks at an endpoint's schema: `required`, `minLength`/`maxLength`, `enum`, `format` constraints are listed.
ONE "happy path" scenario that satisfies all constraints emerges: valid data → expect 201.
VIOLATING each constraint births a separate negative scenario: missing field, too-short/long text, out-of-enum value, invalid format — 5 scenarios.
The lesson — these 6 scenarios are not guesses, they were DIRECTLY derived from the schema; this systematic method is far more thorough than "whatever comes to mind" testing.
The Order for Deriving a Checklist from a Schema
Write the happy path…
One scenario with data satisfying all constraints: expect 2xx.
Add required violations…
A separate scenario for each required field left out one at a time: expect 400.