We con no longer copy an InstanceState via a simple
dereference+assignment because of the mutex which can't be copied. This
adds a set method to properly set all field from another InstanceState,
and take the appropriate locks while doing so.
Add locks to the state structs to handle concurrency during the graph
walks. We can't embed the mutexes due to serialization constraints when
communicating with providers, so expose the Lock/Unlock methods
manually.
Use copystructure.LockedCopy to ensure locks are honored.
Fixes issue where a resource marked as tainted with no other attribute
diffs would never show up in the plan or apply as needing to be
replaced.
One unrelated test needed updating due to a quirk in the testDiffFn
logic - it adds a "type" field diff if the diff is non-Empty. NBD
Fix checksum issue with remote state
If we read a state file with "null" objects in a module and they become
initialized to an empty map the state file may be written out with empty
objects rather than "null", changing the checksum. If we can detect
this, increment the serial number to prevent a conflict in atlas.
Our fakeAtlas test server now needs to decode the state directly rather
than using the ReadState function, so as to be able to read the state
unaltered.
The terraform.State data structures have initialization spread out
throughout the package. More thoroughly initialize State during
ReadState, and add a call to init() during WriteState as another
normalization safeguard.
Expose State.init through an exported Init() method, so that a new State
can be completely realized outside of the terraform package.
Additionally, the internal init now completely walks all internal state
structures ensuring that all maps and slices are initialized. While it
was mentioned before that the `init()` methods are problematic with too
many call sites, expanding this out better exposes the entry points that
will need to be refactored later for improved concurrency handling.
The State structures had a mix of `omitempty` fields. Remove omitempty
for all maps and slices as part of this normalization process. Make
Lineage mandatory, which is now explicitly set in some tests.
Set the default log package output to iotuil.Discard during tests if the
`-v` flag isn't set. If we are verbose, then apply the filter according
to the TF_LOG env variable.
