Support composite builds

[rgoldberg]

Please support composite builds.

If they are currently supposed to work, then please let me know and I'll try again to get Chainsaw 0.3.1 working with my Gradle Wrapper 4.8.1 composite build (on Java 10.0.1+10).

[rgoldberg]

If I have an included build (the dependent build) that depends on another included build (the dependency) through dependency substitution in the composite build:

• the dependency is built
• the dependent build's module path includes the class output directory for the dependency, but the dependent build's javac execution doesn't see the output of the dependency, as indicated by outputting error: module not found errors
• if I iteratively build the composite build:
  • on the first iteration, included builds that do not depend on other included builds build fine, by dependents fail
  • on the subsequent iterations, included builds that only depend on other included builds that have already been built by a previous iteration build fine, by any builds dependent on not-previously-built included builds fail

So, I can eventually get my whole composite build to work, but it takes multiple iterations.

It seems possible that Gradle is building included builds in parallel, and that Chainsaw is not setting up some Gradle included build dependencies properly to force dependencies to to build before dependents. Or, it's possible that Chainsaw is setting up dependency relationships in a reverse order, etc.

I tried to disable parallel builds, but it seems like that didn't work. I've read somewhere that composite builds are always parallel, but I'm not sure if that's correct. If you know how to disable parallelism in composite builds, please let me know.

[rgoldberg]

Chainsaw needs to use CommandLineArgumentProvider instead of adding Strings to compileJava.getOptions().getCompilerArgs().

See Stefan Oehme's (the Gradle core team lead) post at:

https://discuss.gradle.org/t/how-does-a-composite-build-ensure-that-one-included-build-is-built-before-another/27711/2