在 Bug 的泥潭中发现智慧：分享 Debug 的方法与经验

def process_data(data):
    result = []
    for item in data:
        if item % 2 == 0:
            result.append(item / 2)
        else:
            result.append(10 / item)  # 潜在问题
    return result

data = [2, 4, 0, 7]
print(process_data(data))  # ZeroDivisionError: division by zero

def process_data(data):
    result = []
    for item in data:
        print(f"Processing item: {item}")
        if item % 2 == 0:
            result.append(item / 2)
        else:
            print(f"Debug: Attempting division 10 / {item}")
            result.append(10 / item)  # 问题在这里
    return result

def process_data(data):
    result = []
    for item in data:
        if item == 0:  # 修复：增加边界条件检查
            print("Warning: Skipping division by zero.")
            continue
        if item % 2 == 0:
            result.append(item / 2)
        else:
            result.append(10 / item)
    return result

data = [2, 4, 0, 7]
print(process_data(data))  # 输出结果正常

import unittest

class TestProcessData(unittest.TestCase):
    def test_valid_input(self):
        self.assertEqual(process_data([2, 4, 7]), [1.0, 2.0, 10/7])
    
    def test_zero_handling(self):
        self.assertEqual(process_data([0]), [])

git bisect start
git bisect bad HEAD
git bisect good <last_known_good_commit>

# 不规范的命名
a = 100  
b = 200  

# 规范的命名
user_age = 100  
user_score = 200  

# 原始代码：单个函数负责所有逻辑
def process_user_data(data):
    # 数据清理
    clean_data = [item.strip() for item in data if item]
    # 数据计算
    result = sum(len(item) for item in clean_data)
    return result

# 优化代码：分解职责
def clean_data(data):
    return [item.strip() for item in data if item]

def calculate_result(clean_data):
    return sum(len(item) for item in clean_data)

data = ["Alice ", " Bob", " "]
print(calculate_result(clean_data(data)))

import pytest

def is_even(num):
    return num % 2 == 0

# 测试函数
def test_is_even():
    assert is_even(2) == True
    assert is_even(3) == False
    assert is_even(0) == True
    assert is_even(-2) == True

pytest test_file.py

# 没有类型注解
def add_numbers(a, b):
    return a + b

# 增加类型注解
def add_numbers(a: int, b: int) -> int:
    return a + b

mypy script.py

.github/workflows/python-tests.yml
name: Python Tests

on:
  push:
    branches:
      - main

jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v3
      - name: Set up Python
        uses: actions/setup-python@v3
        with:
          python-version: 3.9
      - name: Install dependencies
        run: |
          pip install -r requirements.txt
      - name: Run tests
        run: pytest

# 原始复杂函数
def calculate_total(data):
    return sum(len(item.strip()) for item in data if item)

# 分步测试
def test_calculate_total():
    assert calculate_total(["a", "bb ", "ccc"]) == 6
    assert calculate_total(["", " "]) == 0
    assert calculate_total([]) == 0