Add support for yarn

[igrayson]

Hello 👋. I wasn't sure what the interest level is in this, so I just put together a PR to demonstrate it. My organization uses yarn instead of npm, and this makes concurrently more useful to us.

This adds support for the popular npm replacement, yarn.

ian $ grep watch package.json
    "watch-compile": "node ./scripts/compile-watch.js",
    "watch-generate-client": "node ./scripts/generate-client-watch.js",
    "dev": "yarn compile && concurrently 'yarn compile-watch' 'yarn generate-client-watch'",

ian $ concurrently "yarn:watch-*"
yarn run v1.10.1
yarn run v1.10.1
$ node ./scripts/generate-client-watch.js
$ node ./scripts/compile-watch.js
[watch-generate-client] Watching /Users/ian/workspace/interface/**/*.proto for changes.
[watch-compile] 10:57:39 - Starting compilation in watch mode...
[watch-compile] 10:57:41 - Found 0 errors. Watching for file changes.
[watch-generate-client] Interface file changed: rpc_interface.proto
[watch-generate-client]   Generating: /Users/ian/workspace/client-generated/generated-schema.json
[watch-generate-client]   Generating: /Users/ian/workspace/client-generated/generated-client.js
[watch-generate-client]   Generating: /Users/ian/workspace/client-generated/generated-client.d.ts
[watch-generate-client]   Generating: /Users/ian/workspace/client-generated/package.json
[watch-generate-client]   Generating: /Users/ian/workspace/client-generated/index.ts
[watch-compile] 10:57:44 - File change detected. Starting incremental compilation...
[watch-compile] 10:57:44 - Found 0 errors. Watching for file changes.

[coveralls]

Pull Request Test Coverage Report for Build 321

• 2 of 2 (100.0%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 99.178%

---

Totals
Change from base Build 320:	0.0%
Covered Lines:	239
Relevant Lines:	239

---

💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 324

• 2 of 2 (100.0%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 99.178%

---

Totals
Change from base Build 320:	0.0%
Covered Lines:	239
Relevant Lines:	239

---

💛 - Coveralls

[gustavohenke]

Thanks for implementing this!
I had in mind that someone would like to have yarn support very soon when rewriting concurrently for the v4 release...

You took a good approach here.
However I feel we need to adjust something: yarn run <script> -- <args> isn't exactly the optimal way to call a yarn script.

It yields this for me:

$ yarn test:watch -- home
yarn run v1.7.0
warning From Yarn 1.0 onwards, scripts don't require "--" for options to be forwarded. In a future version, any explicit "--" will be forwarded as-is to the scripts.

I think there should be some per-tool customisation in the command building.
The other option would be to split the implementations.

What do you think?

[igrayson]

I may not fully understand the concern. When I look at how our tool builds commands, I don't see a scenario where we add --s. To my understanding, concurrently would only execute yarn test:watch -- home if the input from the user included the double-dash.

E.g. concurrently "yarn:test:* -- home" -> yarn test:watch -- home, and
concurrently "yarn:test:* home" -> yarn test:watch home. To me, this behavior seems like what we want?

[gustavohenke]

Oh, sorry. You are correct.
I probably got this impression from the tests, as they are using npm-tailored commands (with --). Therefore your improvement looks good to me :)

[gustavohenke]

Published on v4.1.0! 🚢