Issue #2400 Shared cache for built dependencies

[kenji21]

See discussion in issue #2400

[houndci-bot]

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[tmspzz]

@kenji21 Thanks for the PR 🎉

Can you please comment on the chunks that you have move around and signal them to me? This would make it easier for me to review.

[kenji21]

@blender no problems, just done it, and of course will make all changes you ask for as you know better the project than me

[tmspzz]

LGTM, over to @mdiep

[kenji21]

Do you want me to rebase my commit on top of current master ?

(currently: This branch is 1 commit ahead, 10 commits behind Carthage:master.)

[mdiep]

I'm not sure we should add a shared cache like this that's not opt-in. I was thinking there'd be a flag to turn this on. Since we never clean this out, I'm hesitant to start storing additional data that might fill up users' drives.

[kenji21]

@blender was thinking that adding more and more "command options" was not recommended, so I reused the existing "cache" flag: #2400 (comment)

We have deployed it, and migrating from an older Xcode to a new one (and swift) with this patch makes us being able to update / bootstrap with the new xcode/swiftc version very quickly

[mdiep]

Hmm… I'll take another look

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[GabKlein]

Hello,

Is this MR would solve this issue as well #2120 ?
It seems that introducing a new environment variable to change the value of userCachesURL would solve it.

[kenji21]

Just force-pushed to fix the conflit (arguments of a method I moved were reformatted to split them one per line)

[acecilia]

What is preventing this to move forward?

[kenji21]

this one: #2677 that makes my last "update to master" CI build failing

2019-01-09 12:52:17.688 xctest[7209:30478] Building scheme "Archimedes Mac" in Archimedes.xcodeproj
/Users/travis/build/Carthage/Carthage/Tests/CarthageKitTests/XcodeSpec.swift:362: error: -[CarthageKitTests.XcodeSpec should build for multiple platforms] : failed - expected to be nil, got <Unable to determine framework Swift version: Could not derive version from header file.>

[kenji21]

Ok, I moved my commit to a branch https://github.com/openium/Carthage/tree/feature-2400-shared-cache waiting for #2677 to be solved, so it closed this issue, I'll PR again up to date with current master once #2677 will be fixed

[JWShroyer]

This closed PR doesn't seem to be linked to any other PR, but based off what I was reading in #2677 that code should be implemented in 0.33 by the author, @kenji21. Is this work being worked on elsewhere?

[kenji21]

@JWShroyer: The updated PR is this one : #2716

[JWShroyer]

Thanks! 🙇‍♂️