Due to how the state filter machinery works, passing no arguments is valid
and matches _all_ resources.
It is very unlikely that someone wants to remove everything from state, so
this ends up being a very dangerous default for the "terraform state rm"
command, and surprising for someone who perhaps runs it looking for the
usage information.
So we'll be pragmatic here and reject the no-arguments case for this
command, accepting that it makes the unlikely case of intentionally
deleting all resources harder in order to make it less likely that it
will happen _unintentionally_.
If someone does really want to remove all resources from the state, they
can provide an explicit empty string argument, but this isn't documented
because it's a weird case that doesn't seem worth mentioning.
This fixes#15283.
Fixes#12154
The "-backup" flag before for "state *" CLI had some REALLY bizarre behavior:
it would change the _destination_ state and actually not create any
additional backup at all (the original state was unchanged and the
normal timestamped backup still are written). Really weird.
This PR makes the -backup flag work as you'd expect with one caveat:
we'll _still_ create the timestamped backup file. The timestamped backup
file helps make sure that you always get a backup history when using
these commands. We don't want to make it easy for you to overwrite a
state with the `-backup` flag.
This commit adds the `state rm` command for removing an address from
state. It is the result of a rebase from pull-request #5953 which was
lost at some point during the Terraform 0.7 feature branch merges.
Martin Atkins