Fix PR #5 CI failures in GCS temp-file handling and watcher batch-mode tests

[Copilot]

PR #5 failed CI due to lint violations and three watcher batch-mode test failures introduced by context-manager-based image opening. This updates the affected code/tests to align with current file-handling patterns and test expectations.

• Lint-compliant temp file handling

  • Updated GCS blob download temp file creation to use a context manager in src/dmaf/gcs_watcher.py.
  • Eliminates SIM115 while keeping behavior unchanged.

• GCS watcher test cleanup

  • Updated temp file creation in tests/test_gcs_watcher.py to use context manager semantics.
  • Adjusted local import ordering in the same test module to satisfy ruff import sorting.

• Batch scan test compatibility with Image.open(...) context usage

  • Updated three failing batch-mode tests in tests/test_watcher.py to mock Image.open as a context manager:
    • test_delete_source_enabled_batch_mode
    • test_delete_source_disabled_batch_mode
    • test_delete_source_upload_failure_batch_mode

# before
mock_image_open.return_value = mock_img

# after
mock_image_open.return_value.__enter__.return_value = mock_img

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• photoslibrary.googleapis.com
  • Triggering command: /usr/bin/python python -m pytest tests/ -m not slow -v --cov=dmaf --cov-report=xml --cov-report=term --cov-fail-under=0 (dns block)

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[Copilot]

Pull request overview

This PR fixes CI failures from PR #5 by addressing lint violations and three batch-mode test failures related to context manager usage for image opening. The changes aim to make temporary file handling lint-compliant and update test mocks to match the actual code behavior where batch mode uses Image.open as a context manager.

Changes:

• Updated GCS blob download to use context manager for temp file creation (lint compliance)
• Fixed three batch-mode test mocks to support Image.open as a context manager
• Adjusted import ordering in GCS watcher tests to satisfy ruff

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
src/dmaf/gcs_watcher.py	Converted temp file creation to use context manager for SIM115 lint compliance
tests/test_gcs_watcher.py	Updated temp file handling to use context manager and fixed import ordering
tests/test_watcher.py	Fixed three batch-mode test mocks to configure Image.open as a context manager

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[Copilot]

The variable tmp is referenced outside its scope. After the context manager exits (line 100), tmp.name is accessed on line 102, but tmp is only defined within the with block. To fix this, capture tmp.name in a variable before the context exits, similar to the pattern used in tests/test_gcs_watcher.py lines 72-74.

Suggested change

	blob.download_to_filename(tmp.name)
	logger.debug(f"Downloaded {gcs_path} -> {tmp.name}")
	return Path(tmp.name)
	tmp_name = tmp.name
	blob.download_to_filename(tmp_name)
	logger.debug(f"Downloaded {gcs_path} -> {tmp_name}")
	return Path(tmp_name)