This is an IPython Notebook demonstrating some concepts about automated testing from the "Getting started with automated testing" at PyCon 2013. The talk can be seen on YouTube.

Automated Tests

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   "cells": [
    {
     "cell_type": "heading",
     "level": 1,
     "metadata": {},
     "source": [
      "Code Testing"
     ]
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "The function you want to maintain with tests."
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "def divide(a,b): #simple example, e.g. 'hello world'\n",
      "    return a/b"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 1
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Testing Approaches"
     ]
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": [
      "Simple Original"
     ]
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "This is based on the original example found in this [Youtube video](https://www.youtube.com/watch?v=ukm64IUANwE) about the \"Getting started with automated testing\" talk given by Carl Meyer at PyCon 2013 in Santa Clara.  The video can also be watched at the bottom of this notebook."
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "def test_unity():\n",
      "    assert divide(1,1)==1\n",
      "    \n",
      "def test_bad(): #this is just to show a bad test example\n",
      "    assert divide(1,2)==2\n",
      "\n",
      "def test_zero_divide(): #this should through an error\n",
      "    assert divide(1,0)==inf\n",
      "\n",
      "for func in test_unity, test_bad, test_zero_divide:\n",
      "    try:\n",
      "        func()\n",
      "    except Exception as e:\n",
      "        print(\"{} FAILED: {}\".format(func.__name__, e))\n",
      "    else:\n",
      "        print(\"{} Passed.\".format(func.__name__))"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "test_unity Passed.\n",
        "test_bad FAILED: \n",
        "test_zero_divide FAILED: division by zero\n"
       ]
      }
     ],
     "prompt_number": 2
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": [
      "Possible Notebook Alternative"
     ]
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "The advantage of this version is that is takes up less screen space in the notebook since each additional test takes up only one line."
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Each test in the list of tests is a dictionary that contains\n",
      "# the test name as a key with the value being a tuple, of a  \n",
      "# tuple of the function arguments, and the expected result of\n",
      "# the function.\n",
      "tests = [{'bad test':((1,2),2)},\n",
      "         {'unity test':((1,1),1)},\n",
      "         {'Zero divide':((1,0),inf)}]\n",
      "for Test in tests:\n",
      "    Name = list(Test.keys())[0]\n",
      "    arg ,result = Test[Name]\n",
      "    try:\n",
      "        assert divide(*arg)==result #the test is implemented here\n",
      "    except Exception as e:\n",
      "        print(\"{} - FAILED: {}\".format(Name, e))\n",
      "    else:\n",
      "        print(\"{} - Passed.\".format(Name))"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "bad test - FAILED: \n",
        "unity test - Passed.\n",
        "Zero divide - FAILED: division by zero\n"
       ]
      }
     ],
     "prompt_number": 3
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from IPython.display import YouTubeVideo\n",
      "YouTubeVideo('ukm64IUANwE')"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "html": [
        "\n",
        "            <iframe\n",
        "                width=\"400\"\n",
        "                height=\"300\"\n",
        "                src=\"http://www.youtube.com/embed/ukm64IUANwE\"\n",
        "                frameborder=\"0\"\n",
        "                allowfullscreen\n",
        "            ></iframe>\n",
        "        "
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       "output_type": "pyout",
       "prompt_number": 4,
       "text": [
        "<IPython.lib.display.YouTubeVideo at 0x3d83310>"
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     "cell_type": "code",
     "collapsed": false,
     "input": [],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 4
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