debug-ci

Debug failed CI tests by fetching workflow logs and analyzing failures.

Prerequisites

• gh CLI installed and authenticated (gh auth login)

Instructions

Step 1: Identify Current PR

Get PR info for current branch:

gh pr view --json number,title --jq '"\(.number) \(.title)"' 2>/dev/null || echo "no-pr"

If no PR exists, use branch name for the log directory.

Step 2: Get Latest Workflow Run

Get latest "Rust" workflow run for current branch:

BRANCH=$(git branch --show-current)
gh run list --workflow=Rust --branch=$BRANCH --limit=1 --json databaseId,conclusion,headSha,createdAt

Step 3: Get Job Information

List all jobs from the run:

gh run view <run-id> --json jobs --jq '.jobs[] | {id: .databaseId, name: .name, conclusion: .conclusion}'

Step 4: Download Logs

Create directory and download all job logs, stripping ANSI color codes:

mkdir -p ci-logs/pr-<PR_NUMBER>/
# or: mkdir -p ci-logs/branch-<BRANCH_NAME>/

gh run view --job <job-id> --log | perl -pe 's/\e\[[0-9;]*m//g' > ci-logs/pr-<PR_NUMBER>/<job_name>_<job_id>.log

Sanitize job names for filenames (replace spaces/special chars with underscores).

Step 5: Analyze Failures

1. Read downloaded log files
2. Search for failure patterns: FAILED, error[E, panicked at, assertion failed
3. Extract test names and error messages
4. Read PR diff (gh pr diff) to correlate failures with changes
5. Categorize failures:
   • Real failure: Error in code touched by PR
   • Flaky test: Known flaky or unrelated to changes
   • Infrastructure: Network/timeout issues

Step 6: Report

Provide summary:

• PR number and title
• Run status and commit SHA
• List of downloaded log file paths
• Categorized failures with file:line references
• Recommendations for next steps

Notes

• The ci-logs/ directory should be in .gitignore
• Focus on relevant log sections; files can be large