all: Initial MoveResourceState implementation

.changes/unreleased/NOTES-20240129-084840.yaml

@@ -0,0 +1,8 @@
+kind: NOTES
+body: 'helper/schema: While this Go module will not receive support for moving
+  resource state across resource types, the provider server is updated to handle
+  the new operation, which will be required to prevent errors when updating
+  terraform-plugin-framework or terraform-plugin-mux in the future.'
+time: 2024-01-29T08:48:40.990566-05:00
+custom:
+  Issue: "1307"

helper/schema/grpc_provider.go

@@ -28,6 +28,9 @@ const (
 	newExtraKey = "_new_extra_shim"
 )
 
+// Verify provider server interface implementation.
+var _ tfprotov5.ProviderServer = (*GRPCProviderServer)(nil)
+
 func NewGRPCProviderServer(p *Provider) *GRPCProviderServer {
 	return &GRPCProviderServer{
 		provider: p,
@@ -1208,6 +1211,42 @@ func (s *GRPCProviderServer) ImportResourceState(ctx context.Context, req *tfpro
 	return resp, nil
 }
 
+func (s *GRPCProviderServer) MoveResourceState(ctx context.Context, req *tfprotov5.MoveResourceStateRequest) (*tfprotov5.MoveResourceStateResponse, error) {
+	if req == nil {
+		return nil, fmt.Errorf("MoveResourceState request is nil")
+	}
+
+	ctx = logging.InitContext(ctx)
+
+	logging.HelperSchemaTrace(ctx, "Returning error for MoveResourceState")
+
+	resp := &tfprotov5.MoveResourceStateResponse{}
+
+	_, ok := s.provider.ResourcesMap[req.TargetTypeName]
+
+	if !ok {
+		resp.Diagnostics = []*tfprotov5.Diagnostic{
+			{
+				Severity: tfprotov5.DiagnosticSeverityError,
+				Summary:  "Unknown Resource Type",
+				Detail:   fmt.Sprintf("The %q resource type is not supported by this provider.", req.TargetTypeName),
+			},
+		}
+
+		return resp, nil
+	}
+
+	resp.Diagnostics = []*tfprotov5.Diagnostic{
+		{
+			Severity: tfprotov5.DiagnosticSeverityError,
+			Summary:  "Move Resource State Not Supported",
+			Detail:   fmt.Sprintf("The %q resource type does not support moving resource state across resource types.", req.TargetTypeName),
+		},
+	}
+
+	return resp, nil
+}
+
 func (s *GRPCProviderServer) ReadDataSource(ctx context.Context, req *tfprotov5.ReadDataSourceRequest) (*tfprotov5.ReadDataSourceResponse, error) {
 	ctx = logging.InitContext(ctx)
 	resp := &tfprotov5.ReadDataSourceResponse{}

helper/schema/grpc_provider_test.go

@@ -24,9 +24,6 @@ import (
 	"github.com/hashicorp/terraform-plugin-sdk/v2/terraform"
 )
 
-// The GRPCProviderServer will directly implement the go protobuf server
-var _ tfprotov5.ProviderServer = (*GRPCProviderServer)(nil)
-
 func TestGRPCProviderServerConfigureProvider(t *testing.T) {
 	t.Parallel()
 
@@ -2209,6 +2206,74 @@ func TestGRPCProviderServerGetMetadata(t *testing.T) {
 	}
 }
 
+func TestGRPCProviderServerMoveResourceState(t *testing.T) {
+	t.Parallel()
+
+	testCases := map[string]struct {
+		server   *GRPCProviderServer
+		request  *tfprotov5.MoveResourceStateRequest
+		expected *tfprotov5.MoveResourceStateResponse
+	}{
+		"nil": {
+			server:   NewGRPCProviderServer(&Provider{}),
+			request:  nil,
+			expected: nil,
+		},
+		"request-TargetTypeName-missing": {
+			server: NewGRPCProviderServer(&Provider{}),
+			request: &tfprotov5.MoveResourceStateRequest{
+				TargetTypeName: "test_resource",
+			},
+			expected: &tfprotov5.MoveResourceStateResponse{
+				Diagnostics: []*tfprotov5.Diagnostic{
+					{
+						Severity: tfprotov5.DiagnosticSeverityError,
+						Summary:  "Unknown Resource Type",
+						Detail:   "The \"test_resource\" resource type is not supported by this provider.",
+					},
+				},
+			},
+		},
+		"request-TargetTypeName": {
+			server: NewGRPCProviderServer(&Provider{
+				ResourcesMap: map[string]*Resource{
+					"test_resource": {},
+				},
+			}),
+			request: &tfprotov5.MoveResourceStateRequest{
+				TargetTypeName: "test_resource",
+			},
+			expected: &tfprotov5.MoveResourceStateResponse{
+				Diagnostics: []*tfprotov5.Diagnostic{
+					{
+						Severity: tfprotov5.DiagnosticSeverityError,
+						Summary:  "Move Resource State Not Supported",
+						Detail:   "The \"test_resource\" resource type does not support moving resource state across resource types.",
+					},
+				},
+			},
+		},
+	}
+
+	for name, testCase := range testCases {
+		name, testCase := name, testCase
+
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+
+			resp, err := testCase.server.MoveResourceState(context.Background(), testCase.request)
+
+			if testCase.request != nil && err != nil {
+				t.Fatalf("unexpected error: %s", err)
+			}
+
+			if diff := cmp.Diff(resp, testCase.expected); diff != "" {
+				t.Errorf("unexpected difference: %s", diff)
+			}
+		})
+	}
+}
+
 func TestUpgradeState_jsonState(t *testing.T) {
 	r := &Resource{
 		SchemaVersion: 2,