feat: 新增 timer.py 计时器程序

.gitignore

@@ -0,0 +1,30 @@
+# Python
+__pycache__/
+*.py[cod]
+*$py.class
+*.so
+.Python
+env/
+venv/
+.venv/
+ENV/
+env.bak/
+venv.bak/
+
+# IDE
+.vscode/
+.idea/
+*.swp
+*.swo
+*~
+
+# OS
+.DS_Store
+Thumbs.db
+
+# Virtual environment
+env/
+venv/
+ENV/
+env.bak/
+venv.bak/

test_calculator.py

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+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+"""
+计算器功能测试
+"""
+
+import sys
+import os
+sys.path.insert(0, os.path.dirname(os.path.abspath(__file__)))
+
+from calculator import add, subtract, multiply, divide, calculate
+
+def test_basic_operations():
+    """测试基本运算"""
+    print("测试基本运算...")
+
+    # 测试加法
+    assert add(5, 3) == 8
+    assert add(-2, 3) == 1
+    assert add(0, 0) == 0
+
+    # 测试减法
+    assert subtract(10, 4) == 6
+    assert subtract(3, 7) == -4
+    assert subtract(0, 5) == -5
+
+    # 测试乘法
+    assert multiply(4, 5) == 20
+    assert multiply(-3, 2) == -6
+    assert multiply(0, 100) == 0
+
+    # 测试除法
+    assert divide(10, 2) == 5
+    assert divide(7, 2) == 3.5
+    assert divide(-12, 3) == -4
+
+    print("基本运算测试通过！")
+
+def test_divide_by_zero():
+    """测试除零错误"""
+    print("测试除零错误...")
+    try:
+        divide(5, 0)
+        print("错误: 除零异常未触发")
+        return False
+    except ValueError as e:
+        assert str(e) == "除数不能为零"
+        print("除零错误测试通过！")
+        return True
+
+def test_calculate_function():
+    """测试计算函数"""
+    print("测试calculate函数...")
+
+    # 测试有效表达式
+    assert calculate("5 + 3") == 8
+    assert calculate("10 - 4") == 6
+    assert calculate("4 * 5") == 20
+    assert calculate("10 / 2") == 5
+    assert calculate("7.5 + 2.5") == 10.0
+    assert calculate("-3 * 4") == -12
+
+    # 测试无效表达式
+    test_cases = [
+        ("5 +", "表达式格式错误"),
+        ("+ 3", "表达式格式错误"),
+        ("5 + 3 4", "表达式格式错误"),
+        ("5 & 3", "不支持的运算符"),
+        ("abc + 3", "操作数必须是数字"),
+        ("5 / 0", "除数不能为零"),
+    ]
+
+    for expr, expected_error in test_cases:
+        try:
+            calculate(expr)
+            print(f"错误: 表达式 '{expr}' 应触发错误但未触发")
+            return False
+        except (ValueError, RuntimeError) as e:
+            if expected_error not in str(e):
+                print(f"错误: 表达式 '{expr}' 返回错误 '{e}'，但期望包含 '{expected_error}'")
+                return False
+
+    print("calculate函数测试通过！")
+    return True
+
+def main():
+    """运行所有测试"""
+    print("开始计算器测试...")
+    print("=" * 50)
+
+    try:
+        test_basic_operations()
+        test_divide_by_zero()
+        test_calculate_function()
+
+        print("=" * 50)
+        print("所有测试通过！")
+        return 0
+    except AssertionError as e:
+        print(f"测试失败: {e}")
+        return 1
+    except Exception as e:
+        print(f"测试过程中出现未知错误: {e}")
+        return 1
+
+if __name__ == "__main__":
+    sys.exit(main())

timer.py

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+import time
+import threading
+import sys
+
+class Timer:
+    def __init__(self):
+        self.total_seconds = 0
+        self.remaining_seconds = 0
+        self.is_running = False
+        self.is_paused = False
+        self.thread = None
+
+    def set_timer(self, minutes, seconds):
+        """设置倒计时时间"""
+        self.total_seconds = minutes * 60 + seconds
+        self.remaining_seconds = self.total_seconds
+        print(f"计时器设置为 {minutes} 分 {seconds} 秒")
+
+    def start(self):
+        """开始倒计时"""
+        if self.total_seconds <= 0:
+            print("请先设置计时器时间！")
+            return
+
+        if self.is_running and not self.is_paused:
+            print("计时器已经在运行中！")
+            return
+
+        self.is_running = True
+        self.is_paused = False
+
+        if self.thread is None or not self.thread.is_alive():
+            self.thread = threading.Thread(target=self._countdown)
+            self.thread.daemon = True
+            self.thread.start()
+            print("计时器开始！")
+
+    def pause(self):
+        """暂停计时器"""
+        if not self.is_running:
+            print("计时器未运行！")
+            return
+
+        if self.is_paused:
+            print("计时器已经暂停！")
+            return
+
+        self.is_paused = True
+        print("计时器已暂停")
+
+    def resume(self):
+        """继续计时器"""
+        if not self.is_running:
+            print("计时器未运行！")
+            return
+
+        if not self.is_paused:
+            print("计时器未暂停！")
+            return
+
+        self.is_paused = False
+        print("计时器继续")
+
+    def reset(self):
+        """重置计时器"""
+        self.is_running = False
+        self.is_paused = False
+        self.remaining_seconds = self.total_seconds
+        print("计时器已重置")
+
+    def _countdown(self):
+        """倒计时线程函数"""
+        while self.remaining_seconds > 0 and self.is_running:
+            if not self.is_paused:
+                mins, secs = divmod(self.remaining_seconds, 60)
+                time_format = f"{mins:02d}:{secs:02d}"
+                sys.stdout.write(f"\r剩余时间: {time_format}")
+                sys.stdout.flush()
+                time.sleep(1)
+                self.remaining_seconds -= 1
+
+        if self.remaining_seconds <= 0 and self.is_running:
+            print("\n时间到！计时器结束！")
+            self.is_running = False
+        else:
+            print("\n计时器已停止")
+
+    def get_status(self):
+        """获取计时器状态"""
+        if self.is_running:
+            if self.is_paused:
+                status = "已暂停"
+            else:
+                status = "运行中"
+        else:
+            status = "未运行"
+
+        mins, secs = divmod(self.remaining_seconds, 60)
+        time_format = f"{mins:02d}:{secs:02d}"
+        return f"状态: {status}, 剩余时间: {time_format}"
+
+
+def main():
+    """主函数，提供命令行交互界面"""
+    timer = Timer()
+
+    print("=== Python 计时器 ===")
+    print("命令列表:")
+    print("  set <分钟> <秒> - 设置计时器时间")
+    print("  start           - 开始计时器")
+    print("  pause           - 暂停计时器")
+    print("  resume          - 继续计时器")
+    print("  reset           - 重置计时器")
+    print("  status          - 查看状态")
+    print("  help            - 显示帮助")
+    print("  quit            - 退出程序")
+    print()
+
+    while True:
+        try:
+            command = input(">>> ").strip().lower().split()
+
+            if not command:
+                continue
+
+            cmd = command[0]
+
+            if cmd == "set":
+                if len(command) != 3:
+                    print("用法: set <分钟> <秒>")
+                    continue
+                try:
+                    minutes = int(command[1])
+                    seconds = int(command[2])
+                    if minutes < 0 or seconds < 0:
+                        print("时间不能为负数！")
+                        continue
+                    timer.set_timer(minutes, seconds)
+                except ValueError:
+                    print("请输入有效的数字！")
+
+            elif cmd == "start":
+                timer.start()
+
+            elif cmd == "pause":
+                timer.pause()
+
+            elif cmd == "resume":
+                timer.resume()
+
+            elif cmd == "reset":
+                timer.reset()
+
+            elif cmd == "status":
+                print(timer.get_status())
+
+            elif cmd == "help":
+                print("命令列表:")
+                print("  set <分钟> <秒> - 设置计时器时间")
+                print("  start           - 开始计时器")
+                print("  pause           - 暂停计时器")
+                print("  resume          - 继续计时器")
+                print("  reset           - 重置计时器")
+                print("  status          - 查看状态")
+                print("  help            - 显示帮助")
+                print("  quit            - 退出程序")
+
+            elif cmd == "quit":
+                print("退出计时器程序")
+                break
+
+            else:
+                print(f"未知命令: {cmd}，输入 'help' 查看帮助")
+
+        except KeyboardInterrupt:
+            print("\n程序被中断")
+            break
+        except Exception as e:
+            print(f"发生错误: {e}")
+
+
+if __name__ == "__main__":
+    main()