GitHub PR

Context

Current branch: !git branch --show-current
Upstream tracking: !git rev-parse --abbrev-ref --symbolic-full-name @{u} 2>/dev/null || echo "NONE"
Default branch: !gh repo view --json defaultBranchRef --jq .defaultBranchRef.name 2>/dev/null || echo "main"
Unpushed commits: !git log @{u}.. --oneline 2>/dev/null || git log --oneline -20
Recent commits on this branch: !git log --oneline -20
PR template: !cat .github/PULL_REQUEST_TEMPLATE.md docs/PULL_REQUEST_TEMPLATE.md PULL_REQUEST_TEMPLATE.md 2>/dev/null; ls .github/PULL_REQUEST_TEMPLATE/ 2>/dev/null || echo "NONE"

Let <base> be the default branch above and <head> be the current branch.

Determine whether <head> is fully pushed:

If Upstream tracking is NONE, the branch has never been pushed.
Otherwise, if Unpushed commits lists any commits, the branch is behind its upstream.