The primary spam problem isn't that a single account opens many pull requests on a single repo, but that spammer accounts open many pull requests spread across many repositories. So limiting accounts to a couple of open PRs on my repository won't help much.
I'd rather enforce a limit based on the number of PRs that account opened across all public repositories it doesn't have write access to within the last week. And PRs that were closed without getting merged should be held against the account somehow (perhaps via a "close as unwelcome" option for the maintainer).
I'd rather enforce a limit based on the number of PRs that account opened across all public repositories it doesn't have write access to within the last week. And PRs that were closed without getting merged should be held against the account somehow (perhaps via a "close as unwelcome" option for the maintainer).