Allow subdirectories within git repos in yarn install

[akshetpandey]

Do you want to request a feature or report a bug?
Feature

What is the current behavior?
Unable to install packages that are inside subdirectories in git repos. This is a very common case for monorepos and just repositories that can't have the node package in the root repo.

If the current behavior is a bug, please provide the steps to reproduce.
Not a but

What is the expected behavior?
There should be an availably syntax for yarn add and yarn global add that allows to add packages that are inside subdirectories in a git repo.

It make it much easier to use unreleased code when testing unreleased versions for issues/regressions or fixes that aren't live yet like this ticket microsoft/code-push#428

ex. packages affected by this issue
https://github.com/Microsoft/code-push/tree/master/cli
https://github.com/Microsoft/BotBuilder/tree/master/Node
https://github.com/facebook/react-native/tree/master/react-native-cli
https://github.com/babel/babel/tree/master/packages/babel-cli

Related npm issue: npm/npm#2974

Please mention your node.js, yarn and operating system version.
yarn versions v1.2.1
node version v8.7.0
macOS Sierra 10.12.6

[akshetpandey]

There are a couple of good ideas for syntax to use to specify subdirectories in the linked issue (npm/npm#2974)

Use pip's way of using a query parameter
git+https://git.repo/some_repo.git?subdirectory=subdir_path#branch
or
git+https://git.repo/some_repo.git#branch?path=subdir_path
Although I would assume most url parsers won't parse this one.

Use :: as it is not a valid token for a branch name
git+https://git.repo/some_repo.git#branch::subdir_path
git+https://git.repo/some_repo.git#::subdir_path

[lukescott]

Another idea: git+https://git.repo/some_repo.git/subdir_path#branch. If I were to assume this feature existed, that's what I would try first. The other options would require someone to look up the syntax.

[akshetpandey]

That might be ambiguous depending on how the git server urls are setup.

The url might be something like

git+https://github.com/yarnpkg/yarn/<subdir_path>#branch

Then it become hard to say what is part of the repo path and what is the subdir_path

[lukescott]

Not sure if this applies to every repo, but with Github both git+https://github.com/yarnpkg/yarn and git+https://github.com/yarnpkg/yarn.git work. You could assume anything after .git/ is a sub-directory.

Regardless of syntax it would be nice to have this feature either way. It would be cool to make the syntax intuitive though :).

[akshetpandey]

Oh yea, I was mostly talking about other website, not really github. Sorry my example wasn't the best one to explain it.

[stealthybox]

Long discussion about supporting this in npm:
npm/npm#2974

There are some suggested separators in the thread.

[joshcartme]

I would also like to be able to do this to facilitate working with a monorepo that contains a lot of sub modules. I also found #1570 which discusses this. That was closed in favor of https://github.com/yarnpkg/rfcs/issues/15 but https://github.com/yarnpkg/rfcs/issues/15 doesn't exist anymore so it's hard to tell what if anything was done or decided there.

[matheo]

so yarn doesn't support this yet?
all right, no simpler option than publish and use npm packages :(

[erykpiast]

Yeah, rising popularity of monorepo architectures makes it a crucial feature. Is there any workaround for this, for now? Discussion about public API tend to be years long...

[lukescott]

My # 1 use-case for this is pulling in bug-fixes from monorepo's that haven't been merged or released yet. I often want to keep most of the original packages, but pull in one of the sub-repos with a bug-fix. Currently I am unable to do this, and the workarounds are complex. Being able to reference a Github branch would greatly lower the resistance.

I know there are some people at npm that are highly resistant to the idea of this, and monorepos in general. However, many of the contributors here work on projects that use monorepos. I would suspect that if yarn were to implement this feature and it became popular enough npm would follow suit. A lot of yarn ideas have been implemented in npm later on. yarn to me is the babel of npm.

[sdhull]

@erykpiast couple workarounds that I can think of:

1. clone the target repo somewhere and then use yarn add /path/to/repo/subdirectory
2. or possibly (if it's in your own monorepo) use yarn workspaces?

Or -- this is maybe even crazier -- add the remote in question as a submodule and (optionally move your project files into a subdirectory) then use yarn workspaces?

Disclaimer: I haven't tried either of these approaches and they both add overhead for new developers & your CI builds...