{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## 导入依赖"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [],
   "source": [
    "from unittest.mock import patch\n",
    "\n",
    "from module import call_func"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## 错误的用法"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [],
   "source": [
    "def test_call_func():\n",
    "    def mocked_funny_func():\n",
    "        return \"not funny at all\"\n",
    "\n",
    "    with patch(\"dependency.some_funny_func\", mocked_funny_func):\n",
    "        return_value = call_func()\n",
    "\n",
    "    assert return_value == \"not funny at all\"\n",
    "    print(\"pass\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {
    "scrolled": true
   },
   "outputs": [
    {
     "ename": "AssertionError",
     "evalue": "",
     "output_type": "error",
     "traceback": [
      "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[0;31mAssertionError\u001b[0m                            Traceback (most recent call last)",
      "\u001b[0;32m<ipython-input-7-cfc31d4d8831>\u001b[0m in \u001b[0;36m<module>\u001b[0;34m()\u001b[0m\n\u001b[0;32m----> 1\u001b[0;31m \u001b[0mtest_call_func\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[0;32m<ipython-input-6-55327b276a3a>\u001b[0m in \u001b[0;36mtest_call_func\u001b[0;34m()\u001b[0m\n\u001b[1;32m      6\u001b[0m         \u001b[0mreturn_value\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0mcall_func\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m      7\u001b[0m \u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m----> 8\u001b[0;31m     \u001b[0;32massert\u001b[0m \u001b[0mreturn_value\u001b[0m \u001b[0;34m==\u001b[0m \u001b[0;34m\"not funny at all\"\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[0;31mAssertionError\u001b[0m: "
     ]
    }
   ],
   "source": [
    "test_call_func()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## 正确的用法"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 10,
   "metadata": {},
   "outputs": [],
   "source": [
    "def test_call_func():\n",
    "    def mocked_funny_func():\n",
    "        return \"not funny at all\"\n",
    "\n",
    "    with patch(\"module.some_funny_func\", mocked_funny_func):\n",
    "        return_value = call_func()\n",
    "\n",
    "    assert return_value == \"not funny at all\"\n",
    "    print(\"pass\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 11,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "pass\n"
     ]
    }
   ],
   "source": [
    "test_call_func()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## 解析原理"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 13,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "some_other_value\n",
      "some_value\n"
     ]
    }
   ],
   "source": [
    "# 模拟 dependency.some_funny_func\n",
    "dependency = {}\n",
    "dependency[\"some_funny_func\"] = \"some_value\"\n",
    "\n",
    "# 模拟 module.some_funny_func\n",
    "module = {}\n",
    "module[\"some_funny_func\"] = dependency[\"some_funny_func\"]\n",
    "\n",
    "# 模拟 mock\n",
    "dependency[\"some_funny_func\"] = \"some_other_value\"\n",
    "\n",
    "# 查看结果\n",
    "print(dependency[\"some_funny_func\"])\n",
    "print(module[\"some_funny_func\"])"
   ]
  }
 ],
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    "name": "ipython",
    "version": 3
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   "file_extension": ".py",
   "mimetype": "text/x-python",
   "name": "python",
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