exp init: don't add outs to .gitignore

[dberenbaum]

Addresses #5802 (comment) by not adding to .gitignore during exp init since it breaks for subdirectories. Adding to .gitignore is still done on exp run / repro.

[daavoo]

Out of the scope of the P.R. but was wondering why exp init doesn't use stage.add?

[daavoo]

Need to update tests:

assert scm.is_tracked(".gitignore")

[dberenbaum]

Need to update tests:

Sorry, forgot to remove those lines before before pushing. It should pass now.

Out of the scope of the P.R. but was wondering why exp init doesn't use stage.add?

@skshetry can answer, but I'm guessing from

dvc/dvc/repo/experiments/init.py

Line 254 in 37a20e9

with _disable_logging(), repo.scm_context(autostage=True, quiet=True):

that it's because we need to modify some things like disabling output.

[skshetry]

Out of the scope of the P.R. but was wondering why exp init doesn't use stage.add?

Previously, we used to ask for confirmation in an interactive mode before creating the stage. exp init also auto-stages dvc.yaml and params.yaml file which stage add does not do by default (unless core.autostage=true).

Now, this PR is another reason for not using stage add. stage add also auto-commits the file, whereas dvc exp init may require more processing before committing the file (if not now, in the future anyway), so I don't think stage add is a good fit.

We could extend stage add for sure, but dumping stages are complex and can be done in a lot of ways, I don't want to overcomplicate it with all the complexities that may be introduced by exp init.

[dberenbaum]

I'm fine with keeping the scope of this PR as small as possible for now. Could one of you please review now that the tests have been fixed?

[skshetry]

@dberenbaum, I am a bit hesitant to change the behaviour here, although no strong opinion. I'm okay with:

1. either git-ignoring what we can and leave the rest to repro,
2. git-ignoring by traversing upwards (it's going to require some changes in scmrepo, so definitely not a straightforward fix),
3. or, generate intermediate directories.

DVC expects the path to the output to exist in a lot of places (more in relation to stage's working directory, but usually that's where .dvc files are created by default). WDYT of 1 and 3, or a combination of both options?

[dberenbaum]

@skshetry Can you explain why you are hesitant (and why dvc should generate .gitignore files at all when creating stages)?

I opened a PR for 3 in #7751. That would solve the immediate issue, although the rationale for adding to .gitignore during stage creation is still unclear to me.

[skshetry]

@skshetry Can you explain why you are hesitant (and why dvc should generate .gitignore files at all when creating stages)?

I opened a PR for 3 in #7751. That would solve the immediate issue, although the rationale for adding to .gitignore during stage creation is still unclear to me.

The only concern is that the users may git add accidentally in between, the .gitignore prevents that.

[dberenbaum]

Good point @skshetry. I'll close this one for now since the issue was addressed in #7752. We can come back to it if needed.