Ambiguous module reference: kotlinx.coroutines.core

[oryan-block]

Describe the bug

I'm trying to upgrade to v1.7.3 and add the modules to a module-info file but it seems that kotlinx-coroutines-core and kotlinx-coroutines-core-jvm cause a problem because they have the same module name (I think)

My pom dependencies:

        <dependency>
            <groupId>org.jetbrains.kotlinx</groupId>
            <artifactId>kotlinx-coroutines-core</artifactId>
        </dependency>
        <dependency>
            <groupId>org.jetbrains.kotlinx</groupId>
            <artifactId>kotlinx-coroutines-jdk9</artifactId>
        </dependency>

This seems to happen because kotlinx-coroutines-core-jvm is a dependency of kotlinx-coroutines-jdk9 and it's module name is kotlinx-coroutines-core. At the same time kotlinx-coroutines-core has an implied module name which is its package name.
Am I importing these dependencies wrong?

[qwwdfsad]

Would it be okay for you to attach a reproducing project?

I'm trying to upgrade to v1.7.3

Could you please elaborate on what version you are upgrading from?

[oryan-block]

@qwwdfsad try to checkout this branch: https://github.com/graphql-java-kickstart/graphql-java-tools/tree/upgrade-java-11

Upgrading from v1.6.4

[oryan-block]

btw if I replace these deps with kotlinx-coroutines-core-jvm the warning is gone, but that doesn't seem to be the way to import the project according to the docs

[mjovanc]

@oryan-block Is this still an issue for you? The way I see it you should not add the extension -jvm, it should only be kotlinx-coroutines-core. The packages for the specific platform will be present and common ones.

I could not find the branch now to test.

[oryan-block]

@mjovanc yes this is still a problem. This happens even if I only import kotlinx-coroutines-core
Please check this branch: https://github.com/graphql-java-kickstart/graphql-java-tools/tree/coroutinies-module-reference

[dkhalanskyjb]

In Maven projects, it's ok to depend on the -jvm variant of the Kotlin Multiplatform libraries. In fact, it's more straightforward: all kotlinx-coroutines-core should do in Maven is specify a dependency on kotlinx-coroutines-core-jvm for convenience. I'm not sure why also having kotlinx-coroutines-core in the dependencies causes a warning. Is it only in the IDE, or can you observe it when building the project?

[oryan-block]

@dkhalanskyjb it's not just the IDE, maven also fail to build because it can't see anything in the ambiguous module. Depending on -jvm fixes it. Should the readme be fixed?

I'm not sure why also having kotlinx-coroutines-core in the dependencies causes a warning

Not 100% sure but I do believe it's because both core and core-jvm end up with the same module name.

[fzhinkin]

The issue arise because kotlinx-coroutines-core.jar does not contain a JPMS module, so the JPMS module name is derived from the jar file name (kotlinx.coroutines.core). And that module name conflicts with the actual kotlinx.coroutines.core module when the kotlinx-coroutines-core-jvm dependency is fetched.

As a workaround, we can set some automatic module name explicitly using the Automatic-Module-Name manifest header.
Something like Automatic-Module-Name: kotlinx.coroutines.core.trampoline :)

[oryan-block]

@fzhinkin yep, just need to resolve that conflict.