[WIP] Phase format

[borkaehw]

Description

This is an example of how to add custom phases without changing default rules behavior. This phase introduces formatting to bazelbuild/rules_scala.

Copied most of the code from https://github.com/higherkindness/rules_scala

Motivation

Formatting is a nice-to-have feature.

[borkaehw]

Force pushed to fix format.

[borkaehw]

We are happy to figure out attribution from higherkindness/rules_scala before merging, but wanted to provide an example of the phases architecture.

[psilospore]

Hey @borkaehw,

I have a branch off of this and I'm trying to implement a bloop integration. I did some work off of higherkindness/rules_scala and was referenced to here. So now I'm trying to port over my code.

I read the documentation on adding a phase here: https://github.com/bazelbuild/rules_scala/pull/865/files#diff-3152e63cc3552788493d47c5dde927a2 and I've looked through this PR and mostly referenced the work done for scalafmt to write a bloop phase.

First I wanted to first check if I'm doing the right approach here: https://github.com/lucidsoftware/rules_scala_bazelbuild/compare/phase-format...psilospore:bloop-phase?expand=1#diff-60c470b96b12437fced2f68a105809dd

Secondly, I am having a bit of trouble with indirect dependencies. At runtime I've been getting some class not found exceptions.

I added dependencies like this:

    _scala_maven_import_external(
        name = "bloop-launcher",
        artifact = "ch.epfl.scala:bloop-launcher_2.12:1.2.5",
        licenses = ["notice"],
        server_urls = maven_servers,
    )

    native.bind(
        name = "io_bazel_rules_scala/bloop/blooplauncher",
        actual = "@bloop-launcher",
    )

Then used it like this

scala_binary(
    name = "bloop",
    srcs = glob(["bloop/BloopRunner.scala"]),
    main_class = "io.bazel.rules_scala.bloop.BloopRunner",
    visibility = ["//visibility:public"],
    deps = [
        "//src/java/io/bazel/rulesscala/worker",
        "@scalafmt//:net_sourceforge_argparse4j_argparse4j", #TODO move
        "//external:io_bazel_rules_scala/bloop/bsp4j",
        "//external:io_bazel_rules_scala/bloop/bloopconfig",
        "//external:io_bazel_rules_scala/bloop/blooplauncher",

But then when I use something in blooplauncher it gives me this:

bazel run //scala/bloop:bloop
...
Exception in thread "main" java.lang.NoClassDefFoundError: com/zaxxer/nuprocess/internal/BasePosixProcess

It seems like I'm doing something wrong and I'm pretty new to bazel so I suspect I am.

[ittaiz]

Are you certain BasePosixProcess comes from blooplauncher jar? Do you know that in bazel when using scala_maven_import_external you need to specify the transitive dependencies (or use bazel-deps to specify it for you)?

On Fri, 27 Dec 2019 at 2:23 Syed Akber Jafri ***@***.***> wrote: Hey @borkaehw <https://github.com/borkaehw>, I have a branch off of this and I'm trying to implement a bloop integration. I did some work off of higherkindness/rules_scala <https://github.com/psilospore/rules_scala_bloopy> and was referenced to here. So now I'm trying to port over my code. I read the documentation on adding a phase here: https://github.com/bazelbuild/rules_scala/pull/865/files#diff-3152e63cc3552788493d47c5dde927a2 and I've looked through this PR and mostly referenced the work done for scalafmt to write a bloop phase. First I wanted to first check if I'm doing the right approach here: https://github.com/lucidsoftware/rules_scala_bazelbuild/compare/phase-format...psilospore:bloop-phase?expand=1#diff-60c470b96b12437fced2f68a105809dd Secondly, I am having a bit of trouble with indirect dependencies. At runtime I've been getting some class not found exceptions. I added dependencies like this: _scala_maven_import_external( name = "bloop-launcher", artifact = "ch.epfl.scala:bloop-launcher_2.12:1.2.5", licenses = ["notice"], server_urls = maven_servers, ) native.bind( name = "io_bazel_rules_scala/bloop/blooplauncher", actual = ***@***.***", ) Then used it like this scala_binary( name = "bloop", srcs = glob(["bloop/BloopRunner.scala"]), main_class = "io.bazel.rules_scala.bloop.BloopRunner", visibility = ["//visibility:public"], deps = [ "//src/java/io/bazel/rulesscala/worker", ***@***.***//:net_sourceforge_argparse4j_argparse4j", #TODO move "//external:io_bazel_rules_scala/bloop/bsp4j", "//external:io_bazel_rules_scala/bloop/bloopconfig", "//external:io_bazel_rules_scala/bloop/blooplauncher", But then when I use something in blooplauncher it gives me this: Exception in thread "main" java.lang.NoClassDefFoundError: com/zaxxer/nuprocess/internal/BasePosixProcess It seems like I'm doing something wrong and I'm pretty new to bazel so I suspect I am. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#874?email_source=notifications&email_token=AAKQQF7BGMGYCY3UHMJSS3TQ2VDILA5CNFSM4JJ7S7DKYY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOEHWJ3YQ#issuecomment-569155042>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAKQQF4KL3EL2SQ6TOZZ3IDQ2VDILANCNFSM4JJ7S7DA> .

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[psilospore]

Thanks @ittaiz I was able to figure out how to use bazel-deps to have my bloop runner working.

Are you certain BasePosixProcess comes from blooplauncher jar?

Seems like it does here's the a generated file from bazel-deps

scala_import(
    name = "bloop_launcher",
    exports = [
        "//3rdparty/jvm/com/zaxxer:nuprocess",

[psilospore]

I want to make sure I'm understanding this right. Right now I'm trying to follow the scalafmt example where I just add an additional final phase:

def _add_phase_bloop_singleton_implementation(ctx):
    return [
        _ScalaRulePhase(
            phases = [
                ("$", "", "bloop", _phase_bloop)
                #TODO plan is to make it a phase at the end then replace it later. Only using the output from phases before compile.
                #("=", "compile", "bloop", _phase_bloop),

            ],
        ),
    ]

Where I will generate bloop configs and test if I'm able to make a compile BSP request successfully to bloop. Once that works I'm thinking I would do a replace on the compile phase.

                ("=", "compile", "bloop", _phase_bloop),

Doing that means I would need to return the same struct as compile which seems to be in this shape:

    return struct(
        class_jar = ...,
        coverage = ...,
        full_jars = ...,
        ijar = ...,
        ijars = ...,
        rjars = ...,
        java_jar = ...,
        source_jars = ...,
        merged_provider = ...,
    )

Then I can do something like this except with bloop:

   load("//scala/scalafmt:scala_with_scalafmt.bzl", "scala_binary", "scala_library", "scala_test")

Does that sound like I'm headed towards the right direction?

[borkaehw]

@psilospore Hi there, sorry for late response since I just got back from a long vacation.

add an additional final phase

Just keep in mind phase_final will always be the final phase.

Doing that means I would need to return the same struct as compile which seems to be in this shape

Theoretically yes, otherwise phases after phase_compile may miss something.

Then I can do something like this except with bloop

Yes, if it's merged in. You may also keep this work in your private workspace without opening a PR.

We have made a lot of changes on phase architecture. This phase format PR is very outdated. I would branch off of master and work from there. I will do the same to re-open phase format PR if we decide to move forward.

[borkaehw]

This PR will be replaced by #912.

[psilospore]

Thanks for letting me know I'm headed towards the right direction! @jvican and I would probably be interested in getting this merged in eventually vs having it in another repo.

I'll branch off of master.