Conflict on module B, when migrating module A

[legalsylvain]

Context
Try to port the module pos_environment (https://github.com/OCA/server-env/tree/12.0/pos_environment) from 12.0 to 16.0
Command executed : oca-port --upstream=OCA --fork=legalsylvain --verbose 12.0 16.0 pos_environment

Error :

Port PR #141 (https://github.com/OCA/server-env/pull/141) [12.0][UPD] update dotfiles using copier..
Port it? [y/N]: y
ERROR:
Cmd('git') failed due to: exit code(128)
  cmdline: git am -3 --keep /tmp/tmp1x776n0e/0001-UPD-update-dotfiles-using-copier.patch
Falling back to patching base and 3-way merge...
Auto-merging server_environment_ir_config_parameter/tests/test_server_environment_ircp.py
CONFLICT (content): Merge conflict in server_environment_ir_config_parameter/tests/test_server_environment_ircp.py
Auto-merging server_environment_ir_config_parameter/__manifest__.py
CONFLICT (content): Merge conflict in server_environment_ir_config_parameter/__manifest__.py
Auto-merging server_environment/__manifest__.py
CONFLICT (content): Merge conflict in server_environment/__manifest__.py

Analysis
There are conflict in other module. server_environment still migrated and that I don't want to migrate.

I was expecting that the cherry pick of the commits was filtering the path of the module I want to migrate.

I don't have the issue if I use the "traditional" Method. (Thttps://github.com/OCA/maintainer-tools/wiki/Migration-to-version-16.0#technical-method-to-migrate-a-module-from-150-to-160-branch)

Did I missed something ?

[sebalix]

Hello, to me this is the expected behavior, maybe this feature needs a better documentation/explanation. If a module has to be migrated, oca-port will do this:

• migrate the commit history of the module with the usual git format-patch + git am for the given module folder (and only this one), seeing your logs it seems it did this already
• then it'll check merged pull requests related to this module that you would like to port as well, for instance:
  • when a module B has been created, it could have implemented a hook in module A to be functional, so if you port only the commits related to B you are probably missing the part that adds a hook in A (and if the commit adding this hook is already in the target version, the commit/PR won't be proposed to the user),
  • by doing this check, it will of course detect all PRs that made changes on this module, and if one of this PR also contains changes done on other modules, it'll propose you to port it, but that doesn't mean you should port it (and we are in this case).

Now regarding the PR you are trying to port (OCA/server-env#141), it is about a "copier update", maintenance tasks performed on almost all repositories from time to time, and it is generally something you don't want to port through oca-port (like pre-commit stuff or other technical commits).
By answering "No" to this question you'll be able to blacklist this PR so it won't be shown anymore to you and all others contributors.

Does this answer your question?

[sebalix]

One thing to improve in this regard: if the commit to port is updating several modules, iterate on each path. This will results in several similar commits (same messages, dates etc,) but with different updated paths, like it's already the case with the usual git format-patch per module migration workflow.
Also, if a module path has no manifest file (i.e this module is not ported at all on the target branch), we skip it to avoid useless conflicts.

[sbidoul]

I have had a related issue when porting OCA/queue#866. It has commits that touch queue_job and test_queue_job simultaneously. Since I was doing oca-port origin/18.0 origin/19.0 queue_job it applied parts of the commit on test_queue_job to queue_job.