To avoid spurious template version diffs, the template resource will only create a new template version under specific circumstances.

1. When creating the resource, a template version will be created for each in the list.
2. Subsequentterraform applys will hash the contents of the given directories. The provider will then check if the hash belongs to a template version known of in the previous apply.
   • If the hash doesn't belong to any, a new template version will be created
   • If the hash belongs to a previous template version, but the names are different, the name will be updated.
   • If the hash belongs to a previous template version, and the name is the same (or both auto-generated names), no update will happen.

Therefore, theversionname field should only be set when it's guaranteed that it will be updated whenever the contents of the supplied directory change (such as setting it to the current git commit short-hash). Most users will likely want to use the auto-generated names anyway.

Of note, is that we can determine whether or not a new template version will be created duringterraform plan.

Duringplan, we only compare against the last known versions to handle the case where a user reverts the template to one used multipleapplys prior (such when as undoing a change).
If we stored all the hashes of all previous versions, undoing a change like this would not create a new template version in the list, and would instead be a no-op, or only update the name of an older version, which is likely confusing behaviour.