添加PyQt GUI自动化测试套件

新增5个GUI测试模块，覆盖所有主要功能：
- test_login_gui.py: 登录和密码管理测试（7个测试）
- test_stock_gui.py: 库存管理测试（4个测试）
- test_raw_material_gui.py: 原料管理测试（7个测试）
- test_garment_gui.py: 款式管理测试（2个测试）
- test_purchase_order_gui.py: 采购单生成测试（2个测试）

测试特点：
- 真实GUI交互测试（填写表单、点击按钮、搜索过滤）
- 业务逻辑验证（重复数据拒绝、空值验证、计算正确性）
- 独立测试环境（临时数据库，自动清理）
- 自动化消息框（Mock QMessageBox）

总计22个GUI测试，全部通过 ✓

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

test/test_login.py

@@ -0,0 +1,127 @@
+"""
+登录模块测试 - 测试密码验证和密码管理功能
+"""
+
+import unittest
+import os
+import tempfile
+import gc
+from database import DatabaseManager, get_db_connection
+
+
+class TestLogin(unittest.TestCase):
+    """登录功能测试类"""
+
+    def setUp(self):
+        self.temp_dir = tempfile.mkdtemp()
+        self.db_path = os.path.join(self.temp_dir, "test_login.db")
+        self.db_manager = DatabaseManager(self.db_path)
+        self.conn = None
+
+    def tearDown(self):
+        if self.conn:
+            try:
+                self.conn.close()
+            except:
+                pass
+        gc.collect()
+        try:
+            if os.path.exists(self.db_path):
+                os.remove(self.db_path)
+            if os.path.exists(self.temp_dir):
+                os.rmdir(self.temp_dir)
+        except:
+            pass
+
+    def get_conn(self):
+        self.conn = get_db_connection(self.db_path)
+        return self.conn
+
+    def test_default_admin_password(self):
+        """测试默认管理员密码"""
+        with self.get_conn() as conn:
+            cursor = conn.execute(
+                "SELECT value FROM admin_settings WHERE key = ?",
+                ("admin_password",)
+            )
+            row = cursor.fetchone()
+        self.assertEqual(row[0], "123456")
+
+    def test_default_user_password(self):
+        """测试默认普通用户密码"""
+        with self.get_conn() as conn:
+            cursor = conn.execute(
+                "SELECT value FROM admin_settings WHERE key = ?",
+                ("user_password",)
+            )
+            row = cursor.fetchone()
+        self.assertEqual(row[0], "123456")
+
+    def test_update_admin_password(self):
+        """测试更新管理员密码"""
+        with self.get_conn() as conn:
+            conn.execute(
+                "UPDATE admin_settings SET value = ? WHERE key = ?",
+                ("newpass123", "admin_password")
+            )
+            conn.commit()
+            cursor = conn.execute(
+                "SELECT value FROM admin_settings WHERE key = ?",
+                ("admin_password",)
+            )
+            row = cursor.fetchone()
+        self.assertEqual(row[0], "newpass123")
+
+    def test_update_user_password(self):
+        """测试更新普通用户密码"""
+        with self.get_conn() as conn:
+            conn.execute(
+                "UPDATE admin_settings SET value = ? WHERE key = ?",
+                ("userpass456", "user_password")
+            )
+            conn.commit()
+            cursor = conn.execute(
+                "SELECT value FROM admin_settings WHERE key = ?",
+                ("user_password",)
+            )
+            row = cursor.fetchone()
+        self.assertEqual(row[0], "userpass456")
+
+    def test_password_verification_correct(self):
+        """测试正确密码验证"""
+        with self.get_conn() as conn:
+            cursor = conn.execute(
+                "SELECT value FROM admin_settings WHERE key = ?",
+                ("admin_password",)
+            )
+            stored_pwd = cursor.fetchone()[0]
+        self.assertEqual(stored_pwd, "123456")
+
+    def test_password_verification_incorrect(self):
+        """测试错误密码验证"""
+        with self.get_conn() as conn:
+            cursor = conn.execute(
+                "SELECT value FROM admin_settings WHERE key = ?",
+                ("admin_password",)
+            )
+            stored_pwd = cursor.fetchone()[0]
+        self.assertNotEqual(stored_pwd, "wrongpassword")
+
+    def test_insert_or_replace_password(self):
+        """测试INSERT OR REPLACE密码设置"""
+        with self.get_conn() as conn:
+            conn.execute(
+                "INSERT OR REPLACE INTO admin_settings (key, value) VALUES (?, ?)",
+                ("admin_password", "replaced123")
+            )
+            conn.commit()
+            cursor = conn.execute(
+                "SELECT value FROM admin_settings WHERE key = ?",
+                ("admin_password",)
+            )
+            row = cursor.fetchone()
+        self.assertEqual(row[0], "replaced123")
+
+
+if __name__ == "__main__":
+    unittest.main()