{"id":1371,"date":"2021-04-02T19:29:48","date_gmt":"2021-04-03T02:29:48","guid":{"rendered":"https:\/\/coderpad-staging.io\/?post_type=programming-language&#038;p=1101"},"modified":"2023-03-30T19:53:39","modified_gmt":"2023-03-31T02:53:39","slug":"python-2","status":"publish","type":"programming-language","link":"https:\/\/coderpad.io\/languages\/python-2\/","title":{"rendered":"Python 2"},"content":{"rendered":"\n<p>The Python environment is augmented with a few REPL features as well as some helpful libraries.<\/p>\n\n\n\n<p>The REPL uses&nbsp;<a href=\"http:\/\/ipython.org\/\" target=\"_blank\" rel=\"noopener\">IPython<\/a>&nbsp;to provide a REPL with history, highlighting, and autocomplete. Additionally, whenever you run scripts in CoderPad\u2019s editor, the REPL will deposit you at the exact line and state of any exceptions. If there were no errors, you will have a REPL with access to all of the variables and functions defined in your script.<\/p>\n\n\n\n<p>The libraries included and ready for importing are:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><a href=\"https:\/\/requests.readthedocs.io\/en\/master\/\" target=\"_blank\" rel=\"noopener\">requests<\/a>&nbsp;for simpler HTTP requests.<\/li>\n\n\n\n<li><a href=\"https:\/\/pypi.org\/project\/beautifulsoup4\/\" target=\"_blank\" rel=\"noopener\">beautifulsoup4<\/a>&nbsp;for HTML parsing.<\/li>\n\n\n\n<li><a href=\"http:\/\/www.numpy.org\/\" target=\"_blank\" rel=\"noopener\">numpy<\/a>,&nbsp;<a href=\"http:\/\/www.scipy.org\/\" target=\"_blank\" rel=\"noopener\">scipy<\/a>,&nbsp;<a href=\"http:\/\/pandas.pydata.org\/\" target=\"_blank\" rel=\"noopener\">pandas<\/a>,&nbsp;<a href=\"http:\/\/scikit-learn.org\/\" target=\"_blank\" rel=\"noopener\">scikit-learn<\/a>, and&nbsp;<a href=\"https:\/\/www.statsmodels.org\/\" target=\"_blank\" rel=\"noopener\">statsmodels<\/a>&nbsp;for advanced numerical analysis. Unfortunately, plotting does not work in CoderPad\u2019s purely textual interface at this time.<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"testing\">Testing<\/h3>\n\n\n\n<p>We\u2019ve got a few ways you can test your Python code in CoderPad:<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>The <a href=\"https:\/\/docs.python.org\/2\/library\/unittest.html\" target=\"_blank\" rel=\"noopener\">unittest<\/a>&nbsp;library that ships with Python by default. Here\u2019s a quick example:<\/li>\n<\/ol>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-1\" data-shcb-language-name=\"Python\" data-shcb-language-slug=\"python\"><span><code class=\"hljs language-python shcb-wrap-lines\"><span class=\"hljs-keyword\">import<\/span> unittest\n\n<span class=\"hljs-class\"><span class=\"hljs-keyword\">class<\/span> <span class=\"hljs-title\">TestStringMethods<\/span><span class=\"hljs-params\">(unittest.TestCase)<\/span>:<\/span>\n    <span class=\"hljs-function\"><span class=\"hljs-keyword\">def<\/span> <span class=\"hljs-title\">test_upper<\/span><span class=\"hljs-params\">(self)<\/span>:<\/span>\n        self.assertEqual(<span class=\"hljs-string\">'foo'<\/span>.upper(), <span class=\"hljs-string\">'FOO'<\/span>)\n\n    <span class=\"hljs-function\"><span class=\"hljs-keyword\">def<\/span> <span class=\"hljs-title\">test_isupper<\/span><span class=\"hljs-params\">(self)<\/span>:<\/span>\n        self.assertTrue(<span class=\"hljs-string\">'FOO'<\/span>.isupper())\n        self.assertFalse(<span class=\"hljs-string\">'Foo'<\/span>.isupper())\n\n    <span class=\"hljs-function\"><span class=\"hljs-keyword\">def<\/span> <span class=\"hljs-title\">test_split<\/span><span class=\"hljs-params\">(self)<\/span>:<\/span>\n        s = <span class=\"hljs-string\">'hello world'<\/span>\n        self.assertEqual(s.split(), &#91;<span class=\"hljs-string\">'hello'<\/span>, <span class=\"hljs-string\">'world'<\/span>])\n        <span class=\"hljs-comment\"># s.split should throw when the separator is not a string<\/span>\n        <span class=\"hljs-keyword\">with<\/span> self.assertRaises(TypeError):\n            s.split(<span class=\"hljs-number\">2<\/span>)\n\nunittest.main(exit=<span class=\"hljs-literal\">False<\/span>)<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-1\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">Python<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">python<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<ol class=\"wp-block-list\" start=\"2\">\n<li><a href=\"https:\/\/pytest.org\/en\/latest\/\" target=\"_blank\" rel=\"noopener\">pytest<\/a>. The above snippet of code would look like the following when written for pytest:<\/li>\n<\/ol>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-2\" data-shcb-language-name=\"Python\" data-shcb-language-slug=\"python\"><span><code class=\"hljs language-python shcb-wrap-lines\"><span class=\"hljs-keyword\">import<\/span> pytest\n\n<span class=\"hljs-function\"><span class=\"hljs-keyword\">def<\/span> <span class=\"hljs-title\">test_upper<\/span><span class=\"hljs-params\">()<\/span>:<\/span>\n    <span class=\"hljs-keyword\">assert<\/span> <span class=\"hljs-string\">'foo'<\/span>.upper() == <span class=\"hljs-string\">'FOO'<\/span>\n\n<span class=\"hljs-function\"><span class=\"hljs-keyword\">def<\/span> <span class=\"hljs-title\">test_isupper<\/span><span class=\"hljs-params\">()<\/span>:<\/span>\n    <span class=\"hljs-keyword\">assert<\/span> <span class=\"hljs-string\">'FOO'<\/span>.isupper()\n    <span class=\"hljs-keyword\">assert<\/span> <span class=\"hljs-keyword\">not<\/span> <span class=\"hljs-string\">'Foo'<\/span>.isupper()\n\n<span class=\"hljs-function\"><span class=\"hljs-keyword\">def<\/span> <span class=\"hljs-title\">test_split<\/span><span class=\"hljs-params\">()<\/span>:<\/span>\n    s = <span class=\"hljs-string\">'hello world'<\/span>\n    <span class=\"hljs-keyword\">assert<\/span> s.split() == &#91;<span class=\"hljs-string\">'hello'<\/span>, <span class=\"hljs-string\">'world'<\/span>]\n    <span class=\"hljs-comment\"># s.split should throw when the separator is not a string<\/span>\n    <span class=\"hljs-keyword\">with<\/span> pytest.raises(TypeError):\n        s.split(<span class=\"hljs-number\">2<\/span>)\n\npytest.main()<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-2\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">Python<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">python<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<ol class=\"wp-block-list\" start=\"3\">\n<li><a href=\"https:\/\/github.com\/testing-cabal\/mock\" target=\"_blank\" rel=\"noopener\">mock<\/a>&nbsp;is also available if you need to stub out some behavior. <code>mock<\/code>&nbsp;can be combined with&nbsp;<code>unittest<\/code>&nbsp;and&nbsp;<code>pytest<\/code>. Here\u2019s a quick usage example:<\/li>\n<\/ol>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-3\" data-shcb-language-name=\"Python\" data-shcb-language-slug=\"python\"><span><code class=\"hljs language-python shcb-wrap-lines\"><span class=\"hljs-keyword\">from<\/span> mock <span class=\"hljs-keyword\">import<\/span> Mock\n\nmock = Mock()\nmock.method(<span class=\"hljs-number\">1<\/span>, <span class=\"hljs-number\">2<\/span>, <span class=\"hljs-number\">3<\/span>)\nmock.method.assert_called_with(<span class=\"hljs-string\">'this should break'<\/span>)<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-3\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">Python<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">python<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<ol class=\"wp-block-list\" start=\"4\">\n<li><a href=\"http:\/\/hypothesis.works\/\" target=\"_blank\" rel=\"noopener\">hypothesis<\/a>&nbsp;is available for property-based testing in Python. Calling&nbsp;<code>test_decode_inverts_encode()<\/code>&nbsp;fires up Hypothesis and tries to find an input that breaks your code. You can read more about it on their website, but here\u2019s a stubbed example of how you might test that an encoding and decoding function both work:<\/li>\n<\/ol>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-4\" data-shcb-language-name=\"Python\" data-shcb-language-slug=\"python\"><span><code class=\"hljs language-python shcb-wrap-lines\"><span class=\"hljs-keyword\">from<\/span> hypothesis <span class=\"hljs-keyword\">import<\/span> given\n<span class=\"hljs-keyword\">from<\/span> hypothesis.strategies <span class=\"hljs-keyword\">import<\/span> text\n\n<span class=\"hljs-function\"><span class=\"hljs-keyword\">def<\/span> <span class=\"hljs-title\">encode<\/span><span class=\"hljs-params\">(string)<\/span>:<\/span>\n    <span class=\"hljs-comment\"># return encoded string<\/span>\n\n<span class=\"hljs-function\"><span class=\"hljs-keyword\">def<\/span> <span class=\"hljs-title\">decode<\/span><span class=\"hljs-params\">(string)<\/span>:<\/span>\n    <span class=\"hljs-comment\"># return decoded string<\/span>\n\n<span class=\"hljs-meta\">@given(text())<\/span>\n<span class=\"hljs-function\"><span class=\"hljs-keyword\">def<\/span> <span class=\"hljs-title\">test_decode_inverts_encode<\/span><span class=\"hljs-params\">(s)<\/span>:<\/span>\n    <span class=\"hljs-keyword\">assert<\/span> decode(encode(s)) == s\n\ntest_decode_inverts_encode()<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-4\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">Python<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">python<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>","protected":false},"parent":0,"menu_order":0,"template":"","class_list":["post-1371","programming-language","type-programming-language","status-publish","hentry"],"acf":[],"_links":{"self":[{"href":"https:\/\/coderpad.io\/wp-json\/wp\/v2\/programming-language\/1371","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/coderpad.io\/wp-json\/wp\/v2\/programming-language"}],"about":[{"href":"https:\/\/coderpad.io\/wp-json\/wp\/v2\/types\/programming-language"}],"wp:attachment":[{"href":"https:\/\/coderpad.io\/wp-json\/wp\/v2\/media?parent=1371"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}