Implement collection of object attributes origins

This commit adds the collection of origins for object attributes. If an object attribute has an OriginForTarget, it will be collected and returned as part of the object reference origins.

decoder/expr_object_ref_origins.go

@@ -6,6 +6,7 @@ package decoder
 import (
 	"context"
 
+	"github.com/hashicorp/hcl-lang/lang"
 	"github.com/hashicorp/hcl-lang/reference"
 	"github.com/hashicorp/hcl-lang/schema"
 	"github.com/hashicorp/hcl/v2"
@@ -54,7 +55,64 @@ func (obj Object) ReferenceOrigins(ctx context.Context, allowSelfRefs bool) refe
 				origins = append(origins, elemExpr.ReferenceOrigins(ctx, allowSelfRefs)...)
 			}
 		}
+
+		if aSchema != nil && aSchema.OriginForTarget != nil {
+			address, ok := resolveObjectAddress(attrName, aSchema.OriginForTarget.Address)
+			if !ok {
+				continue
+			}
+
+			origins = append(origins, reference.PathOrigin{
+				Range:      item.Key.Range(),
+				TargetAddr: address,
+				TargetPath: aSchema.OriginForTarget.Path,
+				Constraints: reference.OriginConstraints{
+					{
+						OfScopeId: aSchema.OriginForTarget.Constraints.ScopeId,
+						OfType:    aSchema.OriginForTarget.Constraints.Type,
+					},
+				},
+			})
+		}
 	}
 
 	return origins
 }
+
+func resolveObjectAddress(attrName string, addr schema.Address) (lang.Address, bool) {
+	// This function is a simplified version of the original resolveAttributeAddress
+	// because we don't have an attribute to pass
+
+	address := make(lang.Address, 0)
+
+	if len(addr) == 0 {
+		return lang.Address{}, false
+	}
+
+	for i, s := range addr {
+		var stepName string
+
+		switch step := s.(type) {
+		case schema.StaticStep:
+			stepName = step.Name
+		case schema.AttrNameStep:
+			stepName = attrName
+			// TODO: AttrValueStep? Currently no use case for it
+		default:
+			// unknown step
+			return lang.Address{}, false
+		}
+
+		if i == 0 {
+			address = append(address, lang.RootStep{
+				Name: stepName,
+			})
+			continue
+		}
+		address = append(address, lang.AttrStep{
+			Name: stepName,
+		})
+	}
+
+	return address, true
+}