fix: search all Podman auth file locations per containers-auth.json(5) spec

[pavelanni]

Summary

• Renamed podmanAuthPath() → podmanAuthPaths() to return all candidate
  auth file locations per the containers-auth.json(5) spec
• Search order: $XDG_RUNTIME_DIR/containers/auth.json first (Linux primary),
  then $XDG_CONFIG_HOME/containers/auth.json (fallback, defaults to ~/.config)
• credentialStore() now chains all found Podman stores as fallbacks
• Deduplicates paths when XDG_CONFIG_HOME resolves to the same location
• Added unit tests for all path resolution scenarios

Fixes #45

Test plan

• TestPodmanAuthPaths covers: XDG_RUNTIME_DIR priority, XDG_CONFIG_HOME fallback, deduplication, no-XDG fallback
• Full pkg/oci test suite passes
• golangci-lint clean

🤖 Generated with Claude Code

Summary by CodeRabbit

• Tests

  • Added tests verifying Podman authentication path discovery with proper fallback behavior.

• Improvements

  • Enhanced credential loading to check multiple standard container authentication file locations instead of a single path, improving compatibility across different system configurations.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Enterprise

Run ID: 71c9d63b-db83-4e10-9348-a606697c1952

📥 Commits

Reviewing files that changed from the base of the PR and between 92dde21 and ac734f1.

📒 Files selected for processing (2)

• pkg/oci/credentials_test.go
• pkg/oci/push.go

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📝 Walkthrough

Walkthrough

The PR extends credential loading to search multiple Podman authentication file locations per XDG specification. A new podmanAuthPaths() helper returns an ordered, deduplicated list of candidate paths from XDG_RUNTIME_DIR, XDG_CONFIG_HOME, and ~/.config fallback. credentialStore() now iterates these paths, checks file readability, and combines any found Podman stores with Docker credentials.

Changes

Podman authentication file location support

Layer / File(s)	Summary
Multi-location auth path resolution pkg/oci/push.go	Imports log/slog for debug logging. Implements podmanAuthPaths() helper that returns an ordered slice of candidate containers/auth.json locations derived from XDG_RUNTIME_DIR and XDG_CONFIG_HOME environment variables with ~/.config fallback, ensuring no duplicate entries. Refactors credentialStore() to iterate candidate paths from podmanAuthPaths(), skip missing/unreadable files with debug logs, and build a list of Podman stores to combine with Docker credentials.
Test coverage for path ordering and fallback pkg/oci/credentials_test.go	TestPodmanAuthPaths verifies XDG_RUNTIME_DIR takes precedence in returned paths, XDG_CONFIG_HOME appears as fallback, duplicate directories are deduplicated to a single entry, and unset XDG variables fall back to ~/.config/containers/auth.json via os.UserHomeDir().

🎯 2 (Simple) | ⏱️ ~12 minutes

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 50.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately and concisely summarizes the main change: searching all Podman auth file locations per the containers-auth.json(5) spec instead of a single path.
Linked Issues check	✅ Passed	The PR fully implements the requirements from issue #45: searching XDG_RUNTIME_DIR first, then XDG_CONFIG_HOME, with Docker fallback, and includes comprehensive test coverage.
Out of Scope Changes check	✅ Passed	All changes are directly related to implementing the spec-compliant Podman auth file location search per issue #45; no unrelated modifications detected.

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✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch bug/linux-auth-paths

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[coderabbitai]

Actionable comments posted: 0