17 comments

  • rao-v 2 days ago

    This seems like a near perfect use of coding LLMs and a useful way to implement reinforcement learning.

    “Add a major bug to this file that is not covered by existing tests” vs “Find the bug in this file” vs “write a sensible test in this file that protects against this type of bug”

    • infogulch 2 days ago

      Somehow that reminds me of how diffusion models are trained.

      • acheong08 a day ago

        I'm pretty sure that's the premise for GANs (generative adversarial networks) rather than diffusion. Diffusion is more about noise reduction than pitting models against each other

  • IshKebab a day ago

    This is called mutation testing and is very common in formal silicon verification.

    https://en.wikipedia.org/wiki/Mutation_testing

    A downside of naively changing source code is that you have to recompile the code for every mutant, which can be very slow (especially for Rust!). Obviously the right thing to do is to decide at runtime whether to insert a bug or not for each mutation point.

    I had a brief skim through the help for cargo-mutants and it looks like it takes the naive approach which is rather unfortunate.

  • gtramont a day ago

    Here's a list of mutation testing tools for various languages: https://github.com/theofidry/awesome-mutation-testing

    If you're looking for an option for Go, https://github.com/gtramontina/ooze can be of help. It was heavily inspired by https://github.com/zimmski/go-mutesting

  • stblack 2 days ago

    At RustConf 2024 in Montreal, Cargo-mutants' creator Martin Pool's presentation was excellent. One of the best sessions of the conference.

    https://www.youtube.com/watch?v=PjDHe-PkOy8

  • mcdeltat a day ago

    This is a cool project. Related fun anecdote: I once found an application at work where just about the ENTIRE test suite was a no-op as the author (and subsequent copy-pasters) misunderstood a GTest feature. Yep, dozens of unit tests which did not actually test anything. Fortunately the application did mostly work and wasn't critical. Experiences like these make me want to write "negative tests" to test test failure conditions.

    • 01HNNWZ0MV43FF a day ago

      That's why I practice "red, green, refactor". I must see a new test fail once before I believe that its passing means anything

      This generalizes into the strategy that learning and programming are both skimming the edge of an envelope, alternating between things that work and things that almost work

  • J_Shelby_J 2 days ago

    Neat.

    Is this to be used in addition to the tools mentioned in this talk: https://youtube.com/watch?v=qfknfCsICUM

  • kilroy123 a day ago

    Really cool! I wish there was such a thing for JavaScript.

    I say this as a so-so software engineer. I badly wish there was more emphasis on increasing software quality. There is so much the industry could do to radically improve quality, such as tools like this.

    I know the incentives just aren't there, but still.

    • NotAnOtter a day ago

      There is such a thing. Basically every popular language has a mutation-testing frameworks. It's pretty common for large scale projects.

    • MaoSYJ a day ago

      Good news it is a thing in js!

      https://stryker-mutator.io/

      There was some hype about it some years ago.

  • matthewfcarlson 2 days ago

    I wonder if there’s something similar to run on a c codebase.

  • ramon156 2 days ago

    Need to replace the :zombie: with a