Bump fails when run on the very first commit in a repository
If a new repository is based on a template containing a workflow with this action, it may end up being run on the very first commit. However, since that commit is not based on a PR it causes the action to fail. It would be nice if it could instead emit a default version number or at least have the option of doing so. Perhaps it could be configurable: some option that does nothing if unset or emits the specified value if run on the first commit.
The intended behavior of the action is to ignore anything that doesn't look like a pull request merger. Can you provide an example of the error(s) you're seeing in the scenario you described?
I suppose as a general rule it's understandable that no version is assigned without a PR since it would be impossible to know whether it should be a major, minor, or patch bump. However, the original problem still stands: new repositories created from templates that include this action fail on their initial commits when they otherwise would succeed. Perhaps the appropriate behavior under these conditions would be a no-op.
Thanks for linking to an example. This is likely a bug then. The action should effectively be a no-op when not running in the context of a merged pull request.
I will investigate and resolve this over the weekend.