Rather than relying on interrupting Diff, just make sure Stop was called
on the provider. The DiffFn is protected by a mutex in the mock
provider, which means that the tests can't rely on concurent calls to
diff working.
Now that the local backend can be cancelled during plan and refresh, we
don't really need the testShutdownHook. Simplify the tests by just
checking for Stop being called on the provider.
Add a shutdown hook to verify that a context has been correctly
cancelled, so we can remove the sleep and stop guessing.
Add a plan version of the shutdown test as well.
Previously we did plugin discovery in the main package, but as we move
towards versioned plugins we need more information available in order to
resolve plugins, so we move this responsibility into the command package
itself.
For the moment this is just preserving the existing behavior as long as
there are only internal and unversioned plugins present. This is the
final state for provisioners in 0.10, since we don't want to support
versioned provisioners yet. For providers this is just a checkpoint along
the way, since further work is required to apply version constraints from
configuration and support additional plugin search directories.
The automatic plugin discovery behavior is not desirable for tests because
we want to mock the plugins there, so we add a new backdoor for the tests
to use to skip the plugin discovery and just provide their own mock
implementations. Most of this diff is thus noisy rework of the tests to
use this new mechanism.
Gove LockInfo a Marshal method for easy serialization, and a String
method for more readable output.
Have the state.Locker implementations use LockError when possible to
return LockInfo and an error.
The new test pattern is to chdir into a temp location for the test, but
the prevents us from locating the testdata directory in the source. Add
a source path to testLockState so we can find the statelocker.go source.
This adds a field terraform_version to the state that represents the
Terraform version that wrote that state. If Terraform encounters a state
written by a future version, it will error. You must use at least the
version that wrote that state.
Internally we have fields to override this behavior (StateFutureAllowed),
but I chose not to expose them as CLI flags, since the user can just
modify the state directly. This is tricky, but should be tricky to
represent the horrible disaster that can happen by enabling it.
We didn't have to bump the state format version since the absense of the
field means it was written by version "0.0.0" which will always be
older. In effect though this change will always apply to version 2 of
the state since it appears in 0.7 which bumped the version for other
purposes.