bug: allow requirements.txt to not exist

[amol-]

Intent

Previously rsconnect didn't check that the requirements.txt didn't exist, it did just emit a warning

    Warning: Capturing the environment using 'pip freeze'.
             Consider creating a requirements.txt file instead.

Now instead it errors if the requirements file doesn't exist

Invalid value for '--requirements-file' / '-r': File 'requirements.txt' does not exist.

The change in behavior accidentally slipped in as part of #748 as click.Path unexpectedly validates the default value too even if the option wasn't provided.

Type of Change

• Bug Fix
• New Feature
• Breaking Change

Approach

Just disable exists=True from command line validation, this will restore the previous behavior of issuing the warning.

Automated Tests

Tests in Connect triggered this issue

[github-actions]

PR Preview Action v1.6.3
Preview removed because the pull request was closed.
2025-12-18 19:37 UTC

[github-actions]

☂️ Python Coverage

current status: ✅

Overall Coverage

Lines	Covered	Coverage	Threshold	Status
5235	3970	76%	0%	🟢

New Files

No new covered files...

Modified Files

File	Coverage	Status
rsconnect/main.py	68%	🟢
TOTAL	68%	🟢

updated for commit: e4ea28b by action🐍

[dotNomad]

Very clean fix. Thanks for jumping on this! 🚀

[joshyam-k]

You can manually run the rsconnect-python-tests-at-night workflow https://github.com/posit-dev/connect/actions/workflows/rsconnect-python.yml against this branch to check whether connect CI will pass

[joshyam-k]

passing here: https://github.com/posit-dev/connect/actions/runs/20347555934