LAYER_12_TESTING

Testing Layer Skill

Layer Number: 12 Specification: Metadata Model Spec v0.7.0 Purpose: Defines test coverage using ISP (Input Space Partitioning) Coverage Model, specifying coverage requirements, test cases, and input partitions.

Layer Overview

The Testing Layer captures test coverage strategy:

• COVERAGE MODELS - Overall test coverage requirements
• COVERAGE TARGETS - What needs testing (APIs, features, data)
• INPUT PARTITIONS - Partition input space for systematic coverage
• TEST CASES - Concrete test case sketches
• CONTEXT VARIATIONS - Environmental and contextual variations
• COVERAGE GAPS - Identified gaps in coverage

This layer uses ISP Coverage Model (systematic input space partitioning).

Central Entity: The TestCoverageModel is the core modeling unit.

Entity Types

Core Testing Entities (17 entities)

When to Use This Skill

Activate when the user:

• Mentions "testing", "test coverage", "test cases", "ISP"
• Wants to define test strategy or coverage requirements
• Asks about input partitioning or systematic testing
• Needs to model test cases for APIs, features, or data
• Wants to link testing to requirements or business goals

Cross-Layer Relationships

Outgoing (Testing → Other Layers):

• motivation.supports-goals → Motivation Layer (quality goals)
• motivation.fulfills-requirements → Motivation Layer (test requirements)
• business.covers-process → Business Layer (process coverage)
• api.tests-operation → API Layer (API endpoint testing)
• data.validates-schema → Data Model Layer (data validation)
• ux.tests-view → UX Layer (UI testing)

Incoming (Other Layers → Testing):

• Motivation Layer → Testing (requirements drive coverage)
• API Layer → Testing (operations need test coverage)
• Business Layer → Testing (processes need testing)

Testing Best Practices

1. Systematic partitioning - Use ISP to partition input space
2. Coverage criteria - Define clear coverage criteria
3. Context variations - Test across different contexts
4. Traceability - Link tests to requirements and features
5. Gap analysis - Identify and document coverage gaps
6. Exclusions - Explicitly document what's not tested
7. Outcome categories - Define expected outcomes clearly

Common Commands

# Add coverage model
dr add testing test-coverage-model --name "API Coverage Model"

# Add coverage target
dr add testing test-coverage-target --name "Login API Coverage"

# Add test case sketch
dr add testing test-case-sketch --name "Valid Login Test"

# List coverage models
dr list testing test-coverage-model

# Validate testing layer
dr validate --layer testing

# Export coverage report
dr export --layer testing --format markdown

Example: Login API Coverage Model

id: testing.coverage-model.login-api
name: "Login API Coverage Model"
type: test-coverage-model
properties:
  targets:
    - testing.target.login-endpoint
  coverageCriteria: each-choice
  contextVariations:
    - browser: [Chrome, Firefox, Safari]
    - network: [high-speed, low-speed, offline]
    - device: [desktop, mobile, tablet]
  motivation:
    supports-goals:
      - motivation.goal.quality-assurance
    fulfills-requirements:
      - motivation.requirement.comprehensive-testing

Example: Login Test Coverage Target

id: testing.target.login-endpoint
name: "Login Endpoint Coverage"
type: test-coverage-target
properties:
  targetRef: api.operation.login
  inputFields:
    - name: email
      partitions:
        - valid-email: [user@example.com]
        - invalid-format: [notanemail, @example.com]
        - missing: [null, empty]
    - name: password
      partitions:
        - valid-password: [StrongPass123!]
        - weak-password: [123, abc]
        - missing: [null, empty]
        - too-long: [1000-char-string]
  outcomeCategories:
    - success: 200 OK with auth token
    - invalid-credentials: 401 Unauthorized
    - validation-error: 400 Bad Request
    - rate-limited: 429 Too Many Requests
  testCases:
    - testing.test-case.valid-login
    - testing.test-case.invalid-email
    - testing.test-case.invalid-password
    - testing.test-case.missing-credentials

Example: Test Case Sketch

id: testing.test-case.valid-login
name: "Valid Login Test Case"
type: test-case-sketch
properties:
  target: testing.target.login-endpoint
  description: "Test successful login with valid credentials"
  inputSelection:
    email: valid-email
    password: valid-password
  contextSelection:
    browser: Chrome
    network: high-speed
    device: desktop
  expectedOutcome: success
  expectedResponse:
    status: 200
    body:
      token: JWT token present
      user: User object with id and email
  motivation:
    supports-goals:
      - motivation.goal.secure-authentication

Pitfalls to Avoid

• ❌ Ad-hoc testing without systematic partitioning
• ❌ Missing context variations (only testing happy path)
• ❌ Not documenting coverage gaps
• ❌ No traceability to requirements
• ❌ Missing cross-layer links to tested elements
• ❌ Incomplete outcome categories