rules_jvm_external 6.1 seems to require artifacts or boms list

[ted-xie]

See my repro here: https://github.com/ted-xie/maven_install_bzlmod_onoff. The rules_jvm_external version is 6.1. I am using bazelisk with USE_BAZEL_VERSION=f3133764576d9e9d12d88486d6ec2031beb3ddaf.

I would like to have a single source of truth for maven install artifacts. I would like the MODULE.bazel maven.install() artifact list to be the source of truth.

In this example, I specify the artifact list in MODULE.bazel, generate a lock file, and then in WORKSPACE read that lock file. My expectation is that bazel build commands with --noenable_bzlmod and --enable_bzlmod should work identically.

However, I get a rules_jvm_external error when building with bzlmod disabled:

$ bazelisk build :dummy --noenable_bzlmod

ERROR: An error occurred during the fetch of repository 'my_maven':
[...]

ERROR: An error occurred during the fetch of repository 'my_maven':
[...]
Error in fail: Cannot calculate input hash without artifacts or boms

Meanwhile, the build works correctly with bzlmod disabled:

$ bazelisk build @my_maven//... --enable_bzlmod
INFO: Analyzed 9 targets (102 packages loaded, 3356 targets configured).
INFO: Found 9 targets...
INFO: Elapsed time: 4.431s, Critical Path: 0.02s
INFO: 1 process: 1 internal.
INFO: Build completed successfully, 1 total action

[ted-xie]

cc @ahumesky

[ted-xie]

The opposite configuration also yields the same error: If we specify the artifacts list in WORKSPACE, generate the lockfile, and read it in to MODULE.bazel, with rules_jvm_external 6.1 we'll see the same error complaining about the lack of artifacts or boms.