Split interfaces

Author: SarahFrench

internal/command/workdir/backend_config_state.go

@@ -14,7 +14,8 @@ import (
 	"github.com/hashicorp/terraform/internal/plans"
 )
 
-var _ ConfigState[BackendConfigState] = &BackendConfigState{}
+var _ ConfigState = &BackendConfigState{}
+var _ DeepCopier[BackendConfigState] = &BackendConfigState{}
 var _ Planner[plans.Backend] = &BackendConfigState{}
 
 // BackendConfigState describes the physical storage format for the backend state

internal/command/workdir/config_state.go

@@ -9,13 +9,20 @@ import (
 )
 
 // ConfigState describes a configuration block, and is used to make that config block stateful.
-type ConfigState[T any] interface {
+type ConfigState interface {
 	Empty() bool
 	Config(*configschema.Block) (cty.Value, error)
 	SetConfig(cty.Value, *configschema.Block) error
+}
+
+// DeepCopier implementations can return deep copies of themselves for use elsewhere
+// without mutating the original value.
+type DeepCopier[T any] interface {
 	DeepCopy() *T
 }
 
+// Planner implementations can return a representation of their data that's
+// appropriate for storing in a plan file.
 type Planner[T any] interface {
 	Plan(*configschema.Block, string) (*T, error)
 }

internal/command/workdir/statestore_config_state.go

@@ -15,7 +15,8 @@ import (
 	ctyjson "github.com/zclconf/go-cty/cty/json"
 )
 
-var _ ConfigState[StateStoreConfigState] = &StateStoreConfigState{}
+var _ ConfigState = &StateStoreConfigState{}
+var _ DeepCopier[StateStoreConfigState] = &StateStoreConfigState{}
 var _ Planner[plans.StateStore] = &StateStoreConfigState{}
 
 // StateStoreConfigState describes the physical storage format for the state store