Resolving jar dependencies from skip.yml

[tifroz]

In a transpiled Skip package, I need to include a vendored Android JAR via implementation(files(...)) in Skip/skip.yml.

The problem is that the generated Gradle project lives in different locations depending on how the package is being used:

• package-local generation
• app dependency generation
• skip test parity generation
• Xcode/DerivedData-linked generation

Because of that, a fixed relative path to the JAR works in one context and breaks in another. In my case:

• app/Xcode builds could resolve one relative path
• skip test failed because the generated test Gradle project resolved the same path under a different generated layout
  non-source vendored files are not automatically staged into generated src/main/swift, so pointing at a generated-module-local Vendor/...jar path is also unreliable

I am using a function to check multiple path locations as a workaround, but I am guessing this is not the intended way:

build:
  contents:
    - 'fun resolveMyLibJar(): String {'
    - ' ....'
    - ' return discoveredValidPath'
    - '}'
   - block: 'dependencies'
      contents:
        - 'implementation(files("../SkipSmartView/src/main/swift/Vendor/android/mylib.jar"))' // static path will break depending on where built from
        - 'implementation(files(resolveMyLibJar()))' // dynamic search as an ugly workaround

[dfabulich]

I think there is no "intended" way to handle this in the codebase right now, but it seems like a useful feature. (This could be an opportunity to file your first https://github.com/skiptools/skipstone PR! 😁)

[marcprux]

Dan is right, there isn't (yet) any good built-in way to support this. You can use an absolute path or a URL, both of which have obvious drawbacks if you want to be using a local and build-portable library.

Our current skip.yml handling of dependencies like - 'implementation(…)' is very light-touch: we don't really look at them or analyze them. But your resolveMyLibJar() idea could be a path to having some standard built-in processing for local resources. Something like:

build:
  contents:
   - block: 'dependencies'
      contents:
        - 'implementation(localSkipResource("mylib.jar"))'

And that would just do the right thing for a mylib.jar that was, say, included in the Skip/ folder.

This does bear more consideration and investigation. But if your need a very short-term solution, then your current resolveMyLibJar() might be the easiest thing for the here and now…