refactor-bdd

Skill Type: Actuator (BDD Workflow) Purpose: Refactor BDD implementation and eliminate tech debt (Principle #6) Prerequisites:

• Scenarios are PASSING
• Step definitions exist
• Feature implementation exists

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Agent Instructions

You are in the REFACTOR phase of BDD (SCENARIO → STEP DEFINITIONS → IMPLEMENT → REFACTOR).

Your goal is to improve code quality and eliminate technical debt in:

1. Feature implementation (production code)
2. Step definitions (test code)
3. Scenarios (Gherkin files)

Critical: Scenarios must STILL PASS after refactoring.

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Workflow

Step 1: Refactor Feature Implementation

Apply same tech debt elimination as TDD refactor-phase:

1. Delete Unused Imports (same as TDD)
2. Remove Dead Code (same as TDD)
3. Delete Commented Code (same as TDD)
4. Simplify Complex Logic (same as TDD)
5. Remove Duplication (same as TDD)

See: refactor-phase skill (TDD) for detailed pruning instructions.

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Step 2: Refactor Step Definitions

Improve step definition quality:

2.1 Extract Reusable Steps

Before (duplication):

@given('I am a registered user with email "user1@example.com"')
def step_impl(context):
    context.user = create_user("user1@example.com")

@given('I am a registered user with email "user2@example.com"')
def step_impl(context):
    context.user = create_user("user2@example.com")

After (parameterized):

@given('I am a registered user with email "{email}"')
def step_impl(context, email):
    context.user = create_user(email)

2.2 Extract Test Helpers

Before (logic in step definitions):

@given('I am a logged in user')
def step_impl(context):
    user = User(email="test@example.com")
    user.set_password("TestPass123!")
    user.save()
    token = authenticate(user.email, "TestPass123!")
    context.user = user
    context.token = token

After (extracted to helper):

# test_helpers.py
def create_logged_in_user(email="test@example.com"):
    user = create_test_user(email)
    token = authenticate(user.email, user.password)
    return user, token

# Step definition
@given('I am a logged in user')
def step_impl(context):
    context.user, context.token = create_logged_in_user()

2.3 Simplify Step Logic

Before (complex step):

@when('I submit the login form')
def step_impl(context):
    email = context.email_input if hasattr(context, 'email_input') else None
    password = context.password_input if hasattr(context, 'password_input') else None
    if email is None or password is None:
        raise ValueError("Email and password must be set first")
    try:
        result = login(email, password)
        context.login_result = result
    except Exception as e:
        context.login_error = str(e)

After (simplified):

@when('I submit the login form')
def step_impl(context):
    context.login_result = login(
        context.email_input,
        context.password_input
    )

2.4 Delete Unused Steps

Scan for step definitions with zero usage:

# This step is defined but never used in any scenario
@given('I have a premium account')
def step_impl(context):
    context.user.upgrade_to_premium()
# USAGE: 0 scenarios → DELETE

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Step 3: Refactor Scenarios (Gherkin)

Improve scenario quality:

3.1 Extract Duplicate Preconditions to Background

Before (duplication):

Scenario: Login succeeds
  Given I am on the login page
  And the application is running
  When I enter valid credentials
  Then I should see "Welcome"

Scenario: Login fails
  Given I am on the login page
  And the application is running
  When I enter invalid credentials
  Then I should see "Error"

After (Background):

Background:
  Given the application is running
  And I am on the login page

Scenario: Login succeeds
  When I enter valid credentials
  Then I should see "Welcome"

Scenario: Login fails
  When I enter invalid credentials
  Then I should see "Error"

3.2 Improve Scenario Names

Before (vague):

Scenario: Test login
Scenario: Error case

After (descriptive):

Scenario: Successful login with valid credentials
Scenario: Login fails with invalid email format

3.3 Remove Unused Scenarios

Delete scenarios that:

• Test features no longer in scope
• Are duplicates of other scenarios
• Test implementation details (not behavior)

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Step 4: Run Scenarios (Verify Still Passing)

After EVERY refactoring change:

behave features/authentication.feature -v

Expected: All scenarios STILL PASSING ✓

If scenarios fail: Undo refactoring and try different approach.

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Step 5: Before Committing Checklist

You MUST verify:

• ✅ All scenarios passing
• ✅ No unused imports (feature code + step definitions)
• ✅ No dead code (no unused step definitions)
• ✅ No commented-out code
• ✅ Max cyclomatic complexity ≤ 10
• ✅ No duplicated steps
• ✅ Scenarios use Background for common preconditions

If ANY checklist item fails, DO NOT COMMIT. Fix it first.

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Step 6: Commit Refactoring

Create commit:

git add features/ src/auth/ steps/
git commit -m "REFACTOR: Clean up <REQ-ID> (BDD)

Refactor BDD implementation for user login.

Feature Implementation:
  - Deleted 2 unused imports
  - Simplified login() complexity (8 → 5)
  - Added type hints to all functions

Step Definitions:
  - Extracted 3 steps to reusable helpers
  - Removed 2 unused step definitions
  - Simplified step logic

Scenarios:
  - Extracted common preconditions to Background
  - Improved scenario names for clarity
  - Removed 1 duplicate scenario

Scenarios: 5 scenarios still passing ✓
Tech Debt: 0 violations (Principle #6)
"

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Output Format

When you complete the REFACTOR phase, show:

[REFACTOR Phase - <REQ-ID> (BDD)]

Feature Implementation Refactored:
  ✓ Deleted 2 unused imports
  ✓ Simplified login() - complexity 8 → 5
  ✓ Added type hints to 4 functions
  ✓ Improved docstrings

Step Definitions Refactored:
  ✓ Extracted 3 steps to test_helpers.py
  ✓ Removed 2 unused step definitions
  ✓ Simplified complex step logic
  ✓ Parameterized 2 hard-coded steps

Scenarios Refactored:
  ✓ Extracted Background (2 common steps)
  ✓ Improved 3 scenario names
  ✓ Removed 1 duplicate scenario
  ✓ Better organized scenario order

Tech Debt Pruning (Principle #6):
  ✓ Deleted 2 unused imports
  ✓ Removed 2 unused step definitions (18 lines)
  ✓ Simplified 1 complex function (complexity 8 → 5)

File size changes:
  - src/auth/authentication.py: 167 lines → 142 lines (-15%)
  - steps/authentication_steps.py: 98 lines → 76 lines (-22%)
  - features/authentication.feature: 89 lines → 72 lines (-19%)

Running scenarios...
  ✓ All 5 scenarios still passing

Before Commit Checklist:
  ✓ All scenarios passing
  ✓ No unused imports
  ✓ No dead code (unused steps)
  ✓ No commented-out code
  ✓ Max complexity ≤ 10 (current: 5)
  ✓ Background used for common steps
  ✓ Scenarios well-named

Ready to commit!

Commit: REFACTOR: Clean up <REQ-ID> (BDD)

✅ REFACTOR Phase Complete!

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Prerequisites Check

Before invoking this skill, ensure:

1. Scenarios are PASSING
2. Step definitions exist
3. Feature implementation exists

If prerequisites not met:

• Scenarios failing → Go back to IMPLEMENT phase
• No step definitions → Go back to STEP DEFINITIONS phase
• No scenarios → Go back to SCENARIO phase

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Next Steps

After refactoring complete:

1. Verify all scenarios still pass
2. Create final commit (optional - or use REFACTOR commit as final)
3. Move to next requirement (start new BDD workflow)

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Configuration

This skill respects configuration in .claude/plugins.yml:

plugins:
  - name: "@aisdlc/code-skills"
    config:
      bdd:
        extract_background: true      # Auto-extract common steps
        max_scenario_length: 10       # Max steps per scenario
        require_scenario_tagging: true # Require REQ-* tags
      tech_debt:
        auto_detect_on_refactor: true
        max_complexity: 10

---

BDD-Specific Refactoring

Scenario Organization

Group related scenarios with Scenario Outline:

Before:

Scenario: Login with Visa card
  Given I have a Visa card
  When I pay
  Then payment succeeds

Scenario: Login with Mastercard
  Given I have a Mastercard
  When I pay
  Then payment succeeds

After:

Scenario Outline: Login with supported cards
  Given I have a <card_type> card
  When I pay
  Then payment succeeds

  Examples:
    | card_type  |
    | Visa       |
    | Mastercard |

Step Definition Organization

Group by feature in separate files:

steps/
├── authentication_steps.py  # Login, logout, registration
├── payment_steps.py         # Payment processing
└── common_steps.py          # Shared steps (navigation, etc.)

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Notes

Why refactor BDD?

• Step definitions accumulate over time (pruning needed)
• Scenarios can become verbose (Background helps)
• Production code needs same quality as TDD code
• Principle #6 applies to ALL code (test code too)

What makes BDD different from TDD refactoring:

• Refactor 3 layers: scenarios, steps, implementation
• Scenarios should stay business-focused
• Step definitions should be reusable
• Feature code follows same rules as TDD

Homeostasis Goal:

desired_state:
  scenarios_passing: true
  tech_debt: 0  # In all 3 layers
  step_definitions_reusable: true
  scenarios_concise: true

"Excellence or nothing" 🔥