refactoring-steps.md

1. Function Should Do One Thing

1.1 penniesToDollars

• extract variable
• extract method
• inline variabel

1.2 printXXX

• printHeader
• printTotals
• printExpenses
  • for-loop 분리
  • extract method - printExpenses
  • extract method - totalUpExpenses
    • extract fields - total, mealExpenses
    • initialize in c'tor
    • extract method - totalUpExpenses
    • change signature - remove total, mealExpenses from parameter list

1.3 extract method - getName

1.4 assign field - ReportPrinter printer

• printer가 여러 메소드에서 파라미터로 사용되고 있다
• change signature - remove parameter printer

1.5 extract method - printExpensesAndTotals

• move line up(totalUpExpenses)

1.6 extract method - printExpense from printExpensesAndTotals

• to remove {}

1.7 extract method - isMeal, isOverage

1.8 extract method addTotals from totalUpExpenses

• to remove {}

2. Featuer Envy

2.1 move method - isMeal, isOverage to Expense

• feature envy

3. SRP 위반 해소

3.1 rename ExpenseReport to ExpenseReporter

3.2 extract delegate - ExpenseReport

• BL(totalUpExpenses, addToTotals, addExenses, expenses, total, mealExpenses) 추출

3.3 safely delete unused methods

4. OCP 위반 해소

• replace type code with subclasses

4.1 test 수정 - Expense가 아니라 서브 클래스 생성하도록

• 생성자에서 type 파라미터는 이름과 중복. change signature
• push members down - isMeal, isOverage, getName - keep abstract

4.2 run with coverage로 안 사용되는 코드 타입별로 제거

4.3 remove type : Expense.Type enum 제거