command-line-rust VS nextest

You absolutely must write programs, preferably using tests to ensure you are creating correct and reproducible code. May I suggest starting with my book, Command-Line Rust (O'Reilly, 2022). All the code/data/tests are in https://github.com/kyclark/command-line-rust Note that there are branches showing how to use the 4.x version of clap (command-line argument parser) rather than the 2.33 that was current when the book was published.

I think the best way to start learning a programming language is to write lots of small programs that you probably already know. Rust is a perfect command-line language, so I think it makes sense to start by implementing simple programs like "head" and "grep." I also think one should always learn to write and run tests, so I present my GitHub repo of inputs and tests you might like to use to write 14 such standard Unix command-line utilities: https://github.com/kyclark/command-line-rust If you want guidance on the language, I wrote a book called Command-Line Rust (O'Reilly, 2022) that explains all this code. One caveat is that the "clap" (command-line argument parser) module was at 2.33 when I published but is now v4, so you should look at the appropriate branches for versions of the programs that use the "builder" and "derive" patterns for that module. Or just use any old command-line parser you like as there's no requirement to use "clap." Best of luck to you!

You must write programs in a language in order to learn it. I also firmly believe that learning how to write and run tests is critical to learning any language. I wrote Command-Line Rust (O'Reilly, 2022) for the beginner (in Rust, at least) and with a focus on writing and testing small programs from very simple "Hello, world!" and getting increasingly more complex. You can look at https://github.com/kyclark/command-line-rust for the code/inputs/tests. Best of luck!

Code for the above book

I'm the author of Command-Line Rust (O'Reilly, 2022), which I wrote to introduce the language slowly to beginners by writing and testing short, focused programs. You can look over the code/tests/data at https://github.com/kyclark/command-line-rust. Note that there are branches that show the same programs using a more recent version of the "clap" crate.

I wrote Command-Line Rust (O'Reilly, 2022) to guide beginners in the language. You are challenged to write small functions and programs using tests to verify that everything is correct. You can look over the code and tests at https://github.com/kyclark/command-line-rust. Best of luck in your journey!

Here are the example programs from my book, Command-Line Rust (O'Reilly, 2022), along with the input files and tests: https://github.com/kyclark/command-line-rust

I like to suggest that students write programs they already know (or at least understand). For instance, you probably understand that head shows the first few lines of a text file, and you probably can already implement some version of that in one or two languages you know. Try that in Rust. I wrote 14 BSD/GNU command-line utilities in Rust for learning purposes. I wouldn't consider these high-performance/production programs as they are tailored to learning the language. I also stress how to test programs, so there are tests and inputs you can use to verify your programs match the output of the original programs (or you can modify these to suit your own tastes for how you would like them to work). https://github.com/kyclark/command-line-rust

Here are some more examples you may or may not find useful: https://github.com/kyclark/command-line-rust I tend to have a main() that calls a library's run() function that returns a Result and then exit with a nonzero code and error message on a failure.

We are using cargo-nextest to run the tests in Github Workflows. Some crates do not support running plain cargo test anymore, prefer cargo nextest run instead. You can install cargo-nextest with cargo install cargo-nextest.

I build my programs to be append-only, such that users can always update to new versions with confidence.

For example, I'm the primary author and maintainer of cargo-nextest [1], which is a popular alternative test runner for Rust. Through its history it has had just one regression.

If I did ever release a new major version of nextest, I would definitely keep the old branch going for a while, and make noises about it going out of support within the next X months.

[1] https://nexte.st/

For Rust tests, can this be combined with nextest [0]? (Maelstron provides the cargo maelstron command, and nextest provides the cargo nextest command, with no obvious way to compose them)

I guess an env variable to specify which test command to run (very low level) or something like cargo maelstron --nextest would work (but then how to compose with other test runners?)

Now,

> It's fast. In most cases, Maelstrom is faster than cargo test, even without using clustering.

That's surprising. Why is this the case?

Will Maelstron without clustering (running on a single machine) be faster than nextest as well? (Nextest is also faster than bare cargo test [1])

[0] https://nexte.st/

[1] https://nexte.st/docs/design/how-it-works/

cargo-nextest describes itself as a “next-generation Rust test runner”. To install, you need to run cargo install cargo-nextest.

> On my work I make 1-15 commits a day. If I have to spend thought cycles on the commit message, that is time that goes from other productive endeavours.

I make roughly that many commits a day as well. If something's easy to understand I'll put in a simple commit message (e.g. [1]), but I do put in the effort for more complicated ones.

[1] https://github.com/nextest-rs/nextest/commit/efd194b2e1d8d61...

[2] https://github.com/oxidecomputer/omicron/commit/b07a8f593325...

If you need fancier testing than what's built into Rust, cargo-nextest is becoming quite popular.

https://nexte.st/ is what is getting all the attention as a replacement test harness/framework these days.

I believe cargo-nextest supports running separate binaries concurrently.

Do you already use nextest or something else? That really leans into test parallelism and sounds like a perfect fit for how you structure the tests.