yarn equivalent of npx ?

[sandys]

how is yarn recommending we use npx (that is now core part of npm - npm/npm#17685).

Basically, it acts somewhat like ruby's "bundle exec", other than that it launches the package manager if dependencies are missing. This will sidestep yarn and switch back to npm.

Is there a plan to create a "ypx" equivalent that leverages yarn to do this ?

[Daniel15]

For what it's worth, I think npx was inspired by "yarn create" which is similar but only works for packages prefixed with "create-". Not sure what the plans are here.

[arcanis]

Yup, we currently have yarn create (try using yarn create react-app, for example). We might open it to others verbs in the future, but that's not on the roadmap yet.

[zkat]

I'm working on library-ifying npx. It's not a huge task to grab the existing npx code and just replace the npm-related guts with the yarn-equivalent commands.

I won't add that directly to npx itself, since it's meant to be agnostic: npx performs no operations which clash with people using other package managers. It doesn't even require npm to be on the system, so you can npm rm -g npm and npx will work just fine. So you could say npx is ypx, unless you feel really strongly about cache-sharing, which is a pretty thing.

(in re inspiration: npx is primarily inspired by this long-standing feature request: npm/npm#6053. Most of its functionality centers around fulfilling this need. The auto-install feature was added post-yarn-create, and is definitely intended to be an actual generalized solution to that particular thing -- but it does way more than that)

[BYK]

@sandys - The issue @zkat referenced (npm/npm#6053) is not an issue on yarn since you can just do yarn x (or yarn run x if you want to be explicit) if x is in your ./node_modules/.bin directory. So I don't think there's a pressing need for npx equivalency.

If you think there's a strong need, can you explain why you need it? Eg. what problem will it solve for you?

[MarkBennett]

Does anyone know if yarn exec is similar to bundle exec? I see it on the CLI but not in the docs on the website. A quick play with yarn exec on the command line seems like it runs installed binaries so it might solve your problem @sandys.

[pygy]

FWIW, npm-run is an older utility that allows one to run local node_modules binaries, and it doesn't depend on npm. It doesn't have any options though, whereas npx is full of knobs.

[SimenB]

@BYK Use case is running e.g. ypx greenkeeper-lockfile@1 or ypx danger@2 on CI without adding those as deps to the project itself

[tdmalone]

@SimenB CI usually wouldn't commit the project back to version control though, so it doesn't matter if it adds the dependencies in the process, right?

[dcorking]

@MarkBennett Since yarn exec doesn't run scripts from package.json I don't think it is the right place to add this feature.

[dcorking]

@BYK I am not the OP, but I came to this feature request because I had a package on my local machine but not in my package.json. Therefore my app would run for me, but not for anyone who did a clean install of my app. This is a feature of ruby bundler's bundle exec that I like - it won't run unless all the deps are in the manifest.