This adds "field.#" values to the state/diff with the element count of a
map. This fixes a major issue around not knowing when child elements are
computed when doing variable access of a computed map.
Example, if you have a schema like this:
"foo": &Schema{
Type: TypeMap,
Computed: true,
}
And you access it like this in a resource:
${type.name.foo.computed-field}
Then Terraform will error that "field foo could not be found on resource
type.name". By adding that "foo.#" is computed, Terraform core will pick
up that it WILL exist, so its okay.
This is a refactored solution for PR #616. Functionally this is still
the same change, but it’s implemented a lot cleaner with less code and
less changes to existing parts of TF.
It’s not enough to only check if no new value is set. It can also be
that a new value is set, but contains a variable that cannot be
interpolated until a depending resource is created during the apply
fase.
I actually found this one as one of the acceptance tests for the AWS
ELB resource was failing. It failed with the following error:
```
--- FAIL: TestAccAWSELB_InstanceAttaching (177.83 seconds)
testing.go:121: Step 1 error: Error applying: aws_elb.bar: diffs
didn't match during apply. This is a bug with the resource provider,
please report a bug.
FAIL
exit status 1
FAIL github.com/hashicorp/terraform/builtin/providers/aws 177.882s
```
After a quick look I noticed it was actually a bug in core TF so added
the test and made sure all unit tests and AWS acceptance tests are now
running successfully.
builtin/providers/aws/tags_test.go:56: unrecognized printf verb 'i'
builtin/providers/aws/tags_test.go:59: unrecognized printf verb 'i'
config/config_test.go:101: possible formatting directive in Fatal call
config/config_test.go:157: possible formatting directive in Fatal call
config/module/get_file_test.go:91: missing argument for Fatalf(%s): format reads arg 1, have only 0 args
helper/schema/schema.go:341: arg v.Type for printf verb %s of wrong type: schema.ValueType
helper/schema/schema.go:656: missing argument for Errorf(%s): format reads arg 2, have only 1 args
helper/schema/schema.go:912: arg schema.Type for printf verb %s of wrong type: schema.ValueType
terraform/context.go:178: arg v.Type() for printf verb %s of wrong type: github.com/hashicorp/terraform/config.VariableType
terraform/context.go:486: arg c.Operation for printf verb %s of wrong type: terraform.walkOperation
terraform/diff_test.go💯 arg actual for printf verb %s of wrong type: terraform.DiffChangeType
terraform/diff_test.go:235: arg actual for printf verb %s of wrong type: terraform.DiffChangeType
Prior to this, the diff only contained changed set elements. The issue
with this is that `getSet`, the internal function that reads a set from
the ResourceData, expects that each level (state, config, diff, etc.)
has the _full set_ information. This change was done to fix merging
issues.
Because of this, we need to make sure the full set is visible in the
diff.