<story><title>Speedy Web Compiler – A Rust port of Babel and Closure Compiler</title><url>https://github.com/swc-project/swc</url></story><parent_chain></parent_chain><comment><author>losvedir</author><text>This is really cool. I understand why all the front end tooling is written in JS but it really is a pain to deal with in my experience, especially when it comes to building and deploying. Since they&amp;#x27;re essentially just scripts you have to also install the right versions of node and npm and use npm to install the dependencies (and watch out for native extensions!). It&amp;#x27;s fairly tedious to get it all right, whenever I try it, since I&amp;#x27;m not a pure frontend dev, and things have always changed since the last time I did it. But the promise of this is just dropping in a binary and having it all work!&lt;p&gt;I actually like JS as a programming language for the web, I just don&amp;#x27;t like scripting languages in general for command line tools.</text></comment>
<story><title>Speedy Web Compiler – A Rust port of Babel and Closure Compiler</title><url>https://github.com/swc-project/swc</url></story><parent_chain></parent_chain><comment><author>rattray</author><text>Where are the test cases?&lt;p&gt;Babel&amp;#x27;s parser alone has quite a formidable suite of fixtures (a few thousand as I recall): &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;github.com&amp;#x2F;babel&amp;#x2F;babel&amp;#x2F;tree&amp;#x2F;master&amp;#x2F;packages&amp;#x2F;babel-parser&amp;#x2F;test&amp;#x2F;fixtures&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;github.com&amp;#x2F;babel&amp;#x2F;babel&amp;#x2F;tree&amp;#x2F;master&amp;#x2F;packages&amp;#x2F;babel-pa...&lt;/a&gt;&lt;p&gt;The nice thing about implementing a JS-JS compiler is that there is already a huge number of tests out there, like these, that you can use to TDD your compiler&amp;#x27;s edge-cases.&lt;p&gt;SWC&amp;#x27;s CONTRIBUTING mentions this:&lt;p&gt;&amp;gt; Include tests that cover all non-trivial code. The existing tests in test&amp;#x2F; provide templates on how to test swc&amp;#x27;s behavior in a sandbox-environment. The internal crate testing provides a vast amount of helpers to minimize boilerplate. See [testing&amp;#x2F;lib.rs] for an introduction to writing tests.&lt;p&gt;But I cannot find a `&amp;#x2F;test` directory, and it does not appear in the .gitignore either.&lt;p&gt;EDIT: Ah, the tests are in `&amp;#x2F;tests.rs` with JS embedded inside rust code. This makes it a bit harder to compare directly with babel&amp;#x27;s suite, but claims to be lifted from test262, which babel also based many of their tests on (albeit recategorized). hzoo&amp;#x27;s comment here has details: &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;news.ycombinator.com&amp;#x2F;item?id=18746905&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;news.ycombinator.com&amp;#x2F;item?id=18746905&lt;/a&gt;</text></comment>