<aside> 💡

チャプター完了時点のソースコード

https://github.com/craftgear/api_handson/tree/ch04

</aside>

1. タイトルのチェックをzodのスキーマに追加

    export const TodoSchema = z
      .object({
        id: z.number().brand('TodoId'),
        title: z.string({
          // パース時にタイトルの有無をチェック
          required_error: 'Title is required',
        })
        .trim()
        // パース時にタイトルが一文字以上あるかどうかチェック
        .min(1, { message: 'Title must be at least 1 character long' }),
        done: z.coerce.boolean().default(false),
        doneAt: z.date().optional(),
      });
   

2. 完了チェックの関数を追加

   export const isComplete = (todo: Todo) => todo.done;
   

3. テスト追加

   import { describe, it, expect, expectTypeOf } from 'vitest';
   import {
     parseTodo,
     parseTodoId,
     isComplete, 
     parseNewTodo,
     Todo,
     TodoId,
     NewTodo,
   } from './domain';
   
   describe.concurrent('parseTodo', () => {
      it('parse a valid todo', () => {
        const result = parseTodo({ id: 1, title: "Buy milk" });
        expect(result).toEqual({
          id: 1,
          title: "Buy milk",
          done: false,
        });
        expectTypeOf(result).toEqualTypeOf<Todo>();
        const now = new Date();
        expect(parseTodo({ id: 1, title: 'Buy milk done', done: true, doneAt: now })).toEqual({
          id: 1,
          title: 'Buy milk done',
          done: true,
          doneAt: now,
        });
      });
   
      it('throws an error when title is missing', () => {
        expect(() => parseTodo({ id: 1 })).toThrowError('Title is required');
      });
   
      it('throws an error when title is empty', () => {
        expect(() => parseTodo({ id: 1, title: '' })).toThrowError(
          'Title must be at least 1 character long'
        );
      });
   
      it('throws an error when title is only whitespaces', () => {
        expect(() => parseTodo({ id: 1, title: ' ' })).toThrowError(
          'Title must be at least 1 character long'
        );
      });
   })
   
   describe('parseTodoId', () => {
     it('parse a valid todo id', () => {
       const todoId = parseTodoId(1);
       expectTypeOf(todoId).toEqualTypeOf<TodoId>();
     });
   });
   
   describe.concurrent('parseNewTodo', () => {
     it('parse a valid new todo', () => {
        const result = parseNewTodo({ title: "Buy milk" });
        expect(result).toEqual({
          title: "Buy milk",
          done: false,
        });
        expectTypeOf(result).toEqualTypeOf<NewTodo>();
     });
     
     it('throws an error when title is missing', () => {
       expect(() => parseNewTodo({})).toThrowError('Title is required');
     });
   
     it('throws an error when title is empty', () => {
       expect(() => parseNewTodo({ title: '' })).toThrowError(
         'Title must be at least 1 character long'
       );
     });
   
     it("throws an error when title is only whitespaces", () => {
       expect(() => parseTodo({ title: " " })).toThrowError(
         "Title must be at least 1 character long",
       );
     }); 
   });
   
   describe.concurrent('isComplete', () => {
     it('returns true when todo is completed', () => {
       const todo = parseTodo({ id: 1, title: 'Buy milk', done: true });
       expect(isComplete(todo)).toBe(true);
     });
   
     it('returns false when todo is not completed', () => {
       const todo = parseTodo({ id: 1, title: 'Buy milk', done: false });
       expect(isComplete(todo)).toBe(false);
     });
   });
   

<aside> 💡

ドメイン層のコードはすべての関数が純粋関数になります。

</aside>