opentofu/internal/lang/references.go
Martin Atkins cdd9464f9a Move lang/ to internal/lang/
This is part of a general effort to move all of Terraform's non-library
package surface under internal in order to reinforce that these are for
internal use within Terraform only.

If you were previously importing packages under this prefix into an
external codebase, you could pin to an earlier release tag as an interim
solution until you've make a plan to achieve the same functionality some
other way.
2021-05-17 14:09:07 -07:00

82 lines
3.0 KiB
Go

package lang
import (
"github.com/hashicorp/hcl/v2"
"github.com/hashicorp/terraform/internal/addrs"
"github.com/hashicorp/terraform/internal/configs/configschema"
"github.com/hashicorp/terraform/internal/lang/blocktoattr"
"github.com/hashicorp/terraform/internal/tfdiags"
)
// References finds all of the references in the given set of traversals,
// returning diagnostics if any of the traversals cannot be interpreted as a
// reference.
//
// This function does not do any de-duplication of references, since references
// have source location information embedded in them and so any invalid
// references that are duplicated should have errors reported for each
// occurence.
//
// If the returned diagnostics contains errors then the result may be
// incomplete or invalid. Otherwise, the returned slice has one reference per
// given traversal, though it is not guaranteed that the references will
// appear in the same order as the given traversals.
func References(traversals []hcl.Traversal) ([]*addrs.Reference, tfdiags.Diagnostics) {
if len(traversals) == 0 {
return nil, nil
}
var diags tfdiags.Diagnostics
refs := make([]*addrs.Reference, 0, len(traversals))
for _, traversal := range traversals {
ref, refDiags := addrs.ParseRef(traversal)
diags = diags.Append(refDiags)
if ref == nil {
continue
}
refs = append(refs, ref)
}
return refs, diags
}
// ReferencesInBlock is a helper wrapper around References that first searches
// the given body for traversals, before converting those traversals to
// references.
//
// A block schema must be provided so that this function can determine where in
// the body variables are expected.
func ReferencesInBlock(body hcl.Body, schema *configschema.Block) ([]*addrs.Reference, tfdiags.Diagnostics) {
if body == nil {
return nil, nil
}
// We use blocktoattr.ExpandedVariables instead of hcldec.Variables or
// dynblock.VariablesHCLDec here because when we evaluate a block we'll
// first apply the dynamic block extension and _then_ the blocktoattr
// transform, and so blocktoattr.ExpandedVariables takes into account
// both of those transforms when it analyzes the body to ensure we find
// all of the references as if they'd already moved into their final
// locations, even though we can't expand dynamic blocks yet until we
// already know which variables are required.
//
// The set of cases we want to detect here is covered by the tests for
// the plan graph builder in the main 'terraform' package, since it's
// in a better position to test this due to having mock providers etc
// available.
traversals := blocktoattr.ExpandedVariables(body, schema)
return References(traversals)
}
// ReferencesInExpr is a helper wrapper around References that first searches
// the given expression for traversals, before converting those traversals
// to references.
func ReferencesInExpr(expr hcl.Expression) ([]*addrs.Reference, tfdiags.Diagnostics) {
if expr == nil {
return nil, nil
}
traversals := expr.Variables()
return References(traversals)
}