貸出システム
CoddyのPythonジャーニー「Object Oriented Programming」セクションの一部 — レッスン 57/64。
チャレンジ
中級このチャレンジでは、図書館管理システムに貸出機能を追加します。
library.py を編集し、TODO コメントに従って borrow_book メソッドを実装してください。
その他のファイルは提供されており、ロックされています：
book.py— 前回のチャレンジで作成したBookクラスuser.py—user_id、name、およびbooks_borrowedを保持するUserクラスdriver.py— 実装に対してテストシナリオを実行します
borrow_book(book_isbn, user_id) は、"Book not found"、"User not found"、"Book is not available"、または "Book borrowed successfully" のいずれか一つを正確に返さなければなりません。
自分で試してみよう
from book import Book
from user import User
from library import Library
# 包括的なテストケースハンドラー
test_case = input()
# 基本機能のテスト
if test_case == "borrow_success":
library = Library("Community Library")
# 本とユーザーを追加する
book = Book("The Great Gatsby", "F. Scott Fitzgerald", "123456")
library.add_book(book)
user = User("U001", "Alice")
library.add_user(user)
# 本を借りる
result = library.borrow_book("123456", "U001")
print(result)
print(f"Book available: {book.available}")
print(f"Books borrowed by user: {len(user.books_borrowed)}")
elif test_case == "book_not_found":
library = Library("Community Library")
user = User("U001", "Alice")
library.add_user(user)
result = library.borrow_book("nonexistent", "U001")
print(result)
elif test_case == "user_not_found":
library = Library("Community Library")
book = Book("The Great Gatsby", "F. Scott Fitzgerald", "123456")
library.add_book(book)
result = library.borrow_book("123456", "nonexistent")
print(result)
elif test_case == "book_not_available":
library = Library("Community Library")
# 本とユーザーを追加する
book = Book("The Great Gatsby", "F. Scott Fitzgerald", "123456")
book.available = False # 本はすでに借りられている
library.add_book(book)
user = User("U001", "Alice")
library.add_user(user)
# Try to borrow unavailable book
result = library.borrow_book("123456", "U001")
print(result)
# エッジケースと追加のテスト
elif test_case == "multiple_books":
library = Library("Community Library")
user = User("U001", "Alice")
library.add_user(user)
# 複数の本を作成する
books = [
Book("Book 1", "Author 1", "111"),
Book("Book 2", "Author 2", "222"),
Book("Book 3", "Author 3", "333")
]
for book in books:
library.add_book(book)
# 複数の本を借りる
results = []
for book in books:
results.append(library.borrow_book(book.isbn, "U001"))
for result in results:
print(result)
print(f"Total books borrowed: {len(user.books_borrowed)}")
elif test_case == "multiple_users":
library = Library("Community Library")
book = Book("Popular Book", "Famous Author", "999")
library.add_book(book)
# 複数のユーザーを作成する
users = [
User("U001", "Alice"),
User("U002", "Bob"),
User("U003", "Charlie")
]
for user in users:
library.add_user(user)
# 異なるユーザーで同じ本を借りようとする
result1 = library.borrow_book("999", "U001")
result2 = library.borrow_book("999", "U002") # 失敗するはず
print(result1)
print(result2)
print(f"Book's borrower: {book.borrower.name}")
elif test_case == "return_book":
library = Library("Community Library")
book = Book("The Great Gatsby", "F. Scott Fitzgerald", "123456")
library.add_book(book)
user = User("U001", "Alice")
library.add_user(user)
# 本を借りる
borrow_result = library.borrow_book("123456", "U001")
print(borrow_result)
# 本の状態を確認する
print(f"Book available: {book.available}")
print(f"Book borrower: {book.borrower.name}")
print(f"User's borrowed books: {len(user.books_borrowed)}")
print(f"First borrowed book title: {user.books_borrowed[0].title}")
elif test_case == "empty_library":
library = Library("Empty Library")
result = library.borrow_book("any_isbn", "any_user_id")
print(result)
elif test_case == "borrower_reference":
library = Library("Community Library")
book = Book("The Great Gatsby", "F. Scott Fitzgerald", "123456")
library.add_book(book)
user = User("U001", "Alice")
library.add_user(user)
# 本を借りる
library.borrow_book("123456", "U001")
# 参照を確認する
print(f"Book's borrower name: {book.borrower.name}")
print(f"First book in user's borrowed list: {user.books_borrowed[0].title}")