#21091 Native options discrepancy warning Issue created by bolmstedt Describe the bug When extending a list, items are added twice in the native value, but not in the legacy value. This can be reproduced by creating the following files:

# pants.toml
[GLOBAL]
pants_version = "2.23.0.dev1"
backend_packages = ["pants.backend.docker"]

# .pants.rc
[GLOBAL]
backend_packages = "+['pants.backend.docker.lint.hadolint']"

And then running

pants version

to produce:

15:31:12.47 [WARN] Value mismatch for the option `backend_packages` in scope []:
Legacy value: ['pants.backend.docker', 'pants.backend.docker.lint.hadolint'] of type <class 'list'>, from source CONFIG
Native value: ['pants.backend.docker', 'pants.backend.docker.lint.hadolint', 'pants.backend.docker.lint.hadolint'] of type <class 'list'>, from source CONFIG
...

Pants version 2.23.0.dev1 OS MacOS pantsbuild/pants