Bazel@Head fails because bzlmod example test relies on tilde in repo names

[sgowroji]

CI: https://buildkite.com/bazel/bazel-at-head-plus-downstream/builds/4026#_

Platform: Multiple

Logs:

FAIL: �[0m//:test_with_transition (Exit 1) (see /var/lib/buildkite-agent/.cache/bazel/_bazel_buildkite-agent/0acef35a08d1e3c67dd20c415a7fc51f/execroot/_main/bazel-out/k8-fastbuild-ST-b38abb23f0a1/testlogs/test_with_transition/test.log)
FAIL: test_coverage_sys_path (__main__.ExampleTest)
Error: unexpectedly None : Expected to find toolchain coverage, but it was not found.
FAIL: �[0m//:test (Exit 1) (see /var/lib/buildkite-agent/.cache/bazel/_bazel_buildkite-agent/0acef35a08d1e3c67dd20c415a7fc51f/execroot/_main/bazel-out/k8-fastbuild/testlogs/test/test.log)
FAIL: test_coverage_sys_path (__main__.ExampleTest)
Error: unexpectedly None : Expected to find toolchain coverage, but it was not found.
Error: The command exited with status 1�[0m
error: The plugin docker command hook exited with status 1

Culprit:

CC Greenteam @fweikert

[sgowroji]

CC @rickeylev

[rickeylev]

I wasn't able to repro this. Is this happening, still?

Posterity: it looks like this occurs in the examples/bzlmod workspace in rules_python

[rickeylev]

I can repro now. It requires running bazel coverage, not build.

[rickeylev]

I think I found the problem: The separator char between bzlmod repo names changed to + instead of ~. This is due to bazelbuild/bazel#23098. There was an incompatible flag, so I'm surprised this didn't get reported earlier.

In any case, we can fix the rules_python test. It's just trying to verify the order of some paths and including the ~ character to be more certain about what it's matching. It's easy to change it to match either plus or tilde.