leontrolski.github.io/python-script.html at master · leontrolski/leontrolski.github.io · GitHub

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            leontrolski - cheeky Python shell script
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            ⇦
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        <p><i>2025-07-16</i></p>
        <h1>
            Cheeky Python shell script
        </h1>

<p>Bash has so many gotchas (the <a href="https://til.codeinthehole.com/posts/that-while-read-loops-in-bash-dont-read-lines-with-no-new-line-character/">most recent one I&#39;ve learnt</a>) that some people recommend jumping to Python at some complexity threshold. One of those people is me, and I&#39;d set the threshold pretty low. </p>
<p>Assuming you have <a href="https://docs.astral.sh/uv/">uv</a> installed (you should), the new <a href="https://docs.astral.sh/uv/guides/scripts/">scripts directives</a> make the jump to Python even easier than before.</p>
<p>Here&#39;s an example script with:</p>
<ul>
<li>Nice argument handling via <a href="https://github.com/fastapi/typer">typer</a> - try <code>--help</code></li>
<li>Some globbing</li>
<li>Some regex</li>
<li>Some filthy shell command running</li>
</ul>
<p>A lot of not-using-Python comes down to friction, so make your own skeleton script with your favourite tidbits, then add the equivalent to your <code>.zshrc</code> or whatever:</p>
<pre><code class="lang-shell">function py-script(){curl https://raw.githubusercontent.com/leontrolski/leontrolski.github.io/refs/heads/master/code/my-script > $1 &amp;&amp; chmod +x ./$1;}
</code></pre>
<p>Then just</p>
<pre><code class="lang-shell">py-script foo
./foo <span class="hljs-comment">--help</span>
</code></pre>
<p>bang!</p>
<hr>

<p>The script -  it&#39;s not the most performant (eg. it reads everything into memory everywhere), but it gets the job done.</p>
<pre><code class="lang-python"><span class="hljs-comment">#!/usr/bin/env -S uv run --script</span>
<span class="hljs-comment"># /// script</span>
<span class="hljs-comment"># requires-python = "==3.13"</span>
<span class="hljs-comment"># dependencies = [</span>
<span class="hljs-comment">#   "typer==0.16.0",</span>
<span class="hljs-comment"># ]</span>
<span class="hljs-comment"># ///</span>
<span class="hljs-keyword">from</span> pathlib <span class="hljs-keyword">import</span> Path
<span class="hljs-keyword">import</span> re
<span class="hljs-keyword">from</span> subprocess <span class="hljs-keyword">import</span> check_output
<span class="hljs-keyword">import</span> typer

app = typer.Typer()


<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">sh</span><span class="hljs-params">(cmd: str)</span> -&gt; str:</span>
    <span class="hljs-keyword">return</span> check_output(cmd, shell=<span class="hljs-keyword">True</span>).decode()


<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">main</span><span class="hljs-params">(counts: list[int], *, name: str = <span class="hljs-string">"Oli"</span>)</span>:</span>
    <span class="hljs-keyword">for</span> txt <span class="hljs-keyword">in</span> Path().glob(<span class="hljs-string">"*.txt"</span>):
        <span class="hljs-keyword">for</span> line <span class="hljs-keyword">in</span> txt.read_text().splitlines():
            <span class="hljs-keyword">if</span> match := re.search(<span class="hljs-string">r"==([\d.]+)"</span>, line):
                print(match.groups()[<span class="hljs-number">0</span>])
    commits = sh(<span class="hljs-string">'git log --pretty=format:"%H" | head -10'</span>).splitlines()
    print(f<span class="hljs-string">"Hello {name} {counts=} {' '.join(commits)}"</span>)


typer.run(main)
</code></pre>


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