In a Gradle project with many modules, some MPP and some JVM only, how can I add a dependency in a J...

# multiplatform

[ribesg]

In a Gradle project with many modules, some MPP and some JVM only, how can I add a dependency in a JVM module to the JVM part of a MPP module? This produces an error:

implementation(project(":path:to:mpp-module"))

WARNING: Ignoring dependency of module 'mpp-module' on module 'jvm-module'. Java modules cannot depend on Android modules

[gildor]

Looks that it's Android module, not JVM

[ribesg]

No

[gildor]

At least this warning says about this

[gildor]

Maybe a bug

[ribesg]

The error is pretty clear and absolutely doesn’t say that?

[ribesg]

It sees the MPP project as an Android one instead of looking for the JVM module

[gildor]

It's not an error, it's a warning

[gildor]

But yeah, I mean, it may be a bug for sure

[ribesg]

“Just a warning” that completely prevents IntelliJ from reading the project

[gildor]

Yes, but it's not a compilation error as I understand, which itself looks like a bug

[ribesg]

I managed to make it work, kinda. I cleaned the entire this and reimported it in IntelliJ. The warning is still there but no longer prevents me from working

[ribesg]

I really need a workaround on this. Is there no way to add a specific artifact of another module as dependency?

[gildor]

I would just recommend to create a sample project with reproduction of this bug and report an issue

[louiscad]

@ribesg Does your mpp-module target Android?

[ribesg]

Yes, like all of them. I think I’ve seen multiple open issues close to the once I have

[ribesg]

I just have Android+iOS+JVM modules and JVM modules.

[ribesg]

One solution I can think of is, maybe I can make my JVM modules MPP with just a JVM target?

[louiscad]

That's why. You need to either use a jvm target if possible, or add an android target to your module having the dependency

[ribesg]

I have both @louiscad

[ribesg]

The problem is a kotlin-jvm module depending on a kotlin-multiplatform module having both android and jvm targets is throwing this “warning”

[louiscad]

Can you show me the plugins { … } snippet from your consuming module?

[ribesg]

plugins {
    kotlin
    serialization
}

[ribesg]

(I have this extension)

inline val PluginDependenciesSpec.serialization: PluginDependencySpec
    get() = id("kotlinx-serialization").version(Versions.kotlin)

[louiscad]

It needs to target Android too:

plugins {
    kotlin("multiplatform")
    id("com.android.library")
}

[ribesg]

But I don’t want it to

[ribesg]

It’s a backend module

[ribesg]

Ok I found a matching report https://youtrack.jetbrains.com/issue/KT-30390

[louiscad]

First, you should report the issue (kotl.in/issue), be clear that the JVM-only backend module depends on a multiplatform module targeting both JVM and Android.

Then, for workarounds, you have at least these two choices:
1. Publish your mpp-module as a library to mavenLocal (or another repository if you want), and depend on that maven dependency from your JVM-backend only module.
2. Remove the dependency on Android from your mpp-module, and use the Android APIs in another module depending on it.

[ribesg]

These are not acceptable solutions. I’m gonna try to transform my JVM module into a multiplatform module with only JVM target

[ribesg]

That doesn’t work either. Damn. I’m just not changing my entire project architecture because of a bug. I guess we’ll have to work without IDE until this gets fixed.

[louiscad]

@ribesg My solution #1 doesn't require changing the architecture. Only applying the maven-publish plugin and setting up the artifact names if you want. I have experience and examples customizing or disabling unneeded publications, I can help if you need it.

[ribesg]

I already have the maven-publish plugin applied on the entire thing.

[ribesg]

I guess I could define a custom build task that first publishes those problematic mpp modules to maven local, then run the actual full publish

[ribesg]

You would still need to publish any change to maven local every time

[louiscad]

Yes (to both)

[ribesg]

As stated in the issue report, the problem occurs when reopening a project. I just tried removing all .gradle build .idea *.iml files and reimporting the project, and IntelliJ now works as expected in all files of the project.

I’ll just have to do that every time I add a new module to the project I guess, it’s good enough. Adding that to the issue.