diff --git a/internal/cmd/calendar_raw_test.go b/internal/cmd/calendar_raw_test.go
index 60f6615..f267937 100644
--- a/internal/cmd/calendar_raw_test.go
+++ b/internal/cmd/calendar_raw_test.go
@@ -1,7 +1,6 @@
 package cmd
 
 import (
-	"context"
 	"encoding/json"
 	"net/http"
 	"net/http/httptest"
@@ -9,7 +8,6 @@ import (
 	"testing"
 
 	"google.golang.org/api/calendar/v3"
-	"google.golang.org/api/option"
 )
 
 func newCalendarRawTestServer(t *testing.T, status int, body map[string]any) *httptest.Server {
@@ -42,18 +40,8 @@ func newCalendarRawTestServer(t *testing.T, status int, body map[string]any) *ht
 
 func installMockCalendarService(t *testing.T, srv *httptest.Server) {
 	t.Helper()
-	orig := newCalendarService
-	t.Cleanup(func() { newCalendarService = orig })
-
-	svc, err := calendar.NewService(context.Background(),
-		option.WithoutAuthentication(),
-		option.WithHTTPClient(srv.Client()),
-		option.WithEndpoint(srv.URL+"/"),
-	)
-	if err != nil {
-		t.Fatalf("NewService: %v", err)
-	}
-	newCalendarService = func(context.Context, string) (*calendar.Service, error) { return svc, nil }
+	svc := newGoogleTestServiceWithEndpoint(t, srv.Client(), srv.URL+"/", calendar.NewService)
+	stubGoogleTestService(t, &newCalendarService, svc)
 }
 
 func fullCalendarEventResponse(id string) map[string]any {
diff --git a/internal/cmd/calendar_testutil_test.go b/internal/cmd/calendar_testutil_test.go
index eeb2bce..6176f32 100644
--- a/internal/cmd/calendar_testutil_test.go
+++ b/internal/cmd/calendar_testutil_test.go
@@ -4,11 +4,9 @@ import (
 	"context"
 	"io"
 	"net/http"
-	"net/http/httptest"
 	"testing"
 
 	"google.golang.org/api/calendar/v3"
-	"google.golang.org/api/option"
 
 	"github.com/steipete/gogcli/internal/outfmt"
 	"github.com/steipete/gogcli/internal/ui"
@@ -17,17 +15,7 @@ import (
 func newCalendarServiceForTest(t *testing.T, h http.Handler) (*calendar.Service, func()) {
 	t.Helper()
 
-	srv := httptest.NewServer(h)
-	svc, err := calendar.NewService(context.Background(),
-		option.WithoutAuthentication(),
-		option.WithHTTPClient(srv.Client()),
-		option.WithEndpoint(srv.URL+"/"),
-	)
-	if err != nil {
-		srv.Close()
-		t.Fatalf("NewService: %v", err)
-	}
-	return svc, srv.Close
+	return newGoogleTestService(t, h, calendar.NewService)
 }
 
 func newTestCalendarService(t *testing.T, h http.Handler) (*calendar.Service, func()) {
@@ -37,9 +25,7 @@ func newTestCalendarService(t *testing.T, h http.Handler) (*calendar.Service, fu
 
 func stubCalendarServiceForTest(t *testing.T, svc *calendar.Service) {
 	t.Helper()
-	origNew := newCalendarService
-	t.Cleanup(func() { newCalendarService = origNew })
-	newCalendarService = func(context.Context, string) (*calendar.Service, error) { return svc, nil }
+	stubGoogleTestService(t, &newCalendarService, svc)
 }
 
 func newCalendarOutputContext(t *testing.T, stdout, stderr io.Writer) context.Context {
diff --git a/internal/cmd/drive_raw_test.go b/internal/cmd/drive_raw_test.go
index 319688d..91850ab 100644
--- a/internal/cmd/drive_raw_test.go
+++ b/internal/cmd/drive_raw_test.go
@@ -1,7 +1,6 @@
 package cmd
 
 import (
-	"context"
 	"encoding/json"
 	"net/http"
 	"net/http/httptest"
@@ -10,7 +9,6 @@ import (
 	"testing"
 
 	"google.golang.org/api/drive/v3"
-	"google.golang.org/api/option"
 )
 
 type driveRawHit struct {
@@ -42,18 +40,8 @@ func newDriveRawTestServer(t *testing.T, status int, body map[string]any, hit *d
 
 func installMockDriveService(t *testing.T, srv *httptest.Server) {
 	t.Helper()
-	orig := newDriveService
-	t.Cleanup(func() { newDriveService = orig })
-
-	svc, err := drive.NewService(context.Background(),
-		option.WithoutAuthentication(),
-		option.WithHTTPClient(srv.Client()),
-		option.WithEndpoint(srv.URL+"/"),
-	)
-	if err != nil {
-		t.Fatalf("NewService: %v", err)
-	}
-	newDriveService = func(context.Context, string) (*drive.Service, error) { return svc, nil }
+	svc := newGoogleTestServiceWithEndpoint(t, srv.Client(), srv.URL+"/", drive.NewService)
+	stubGoogleTestService(t, &newDriveService, svc)
 }
 
 // sensitiveDriveFile returns a File response containing every sensitive
diff --git a/internal/cmd/drive_testutil_test.go b/internal/cmd/drive_testutil_test.go
index 8ce9c1f..dfe3c4c 100644
--- a/internal/cmd/drive_testutil_test.go
+++ b/internal/cmd/drive_testutil_test.go
@@ -5,28 +5,16 @@ import (
 	"encoding/json"
 	"io"
 	"net/http"
-	"net/http/httptest"
 	"strings"
 	"testing"
 
 	"google.golang.org/api/drive/v3"
-	"google.golang.org/api/option"
 )
 
 func newDriveTestService(t *testing.T, h http.Handler) (*drive.Service, func()) {
 	t.Helper()
 
-	srv := httptest.NewServer(h)
-
-	svc, err := drive.NewService(context.Background(),
-		option.WithoutAuthentication(),
-		option.WithHTTPClient(srv.Client()),
-		option.WithEndpoint(srv.URL+"/"),
-	)
-	if err != nil {
-		t.Fatalf("NewService: %v", err)
-	}
-	return svc, srv.Close
+	return newGoogleTestService(t, h, drive.NewService)
 }
 
 func stubDriveService(svc *drive.Service) func(context.Context, string) (*drive.Service, error) {
@@ -35,9 +23,7 @@ func stubDriveService(svc *drive.Service) func(context.Context, string) (*drive.
 
 func stubDriveServiceForTest(t *testing.T, svc *drive.Service) {
 	t.Helper()
-	origNew := newDriveService
-	t.Cleanup(func() { newDriveService = origNew })
-	newDriveService = stubDriveService(svc)
+	stubGoogleTestService(t, &newDriveService, svc)
 }
 
 func newDriveMetadataTestService(t *testing.T, mimeType string) (*drive.Service, func()) {
diff --git a/internal/cmd/forms_raw_test.go b/internal/cmd/forms_raw_test.go
index cf1cf6c..08ed282 100644
--- a/internal/cmd/forms_raw_test.go
+++ b/internal/cmd/forms_raw_test.go
@@ -1,7 +1,6 @@
 package cmd
 
 import (
-	"context"
 	"encoding/json"
 	"net/http"
 	"net/http/httptest"
@@ -9,7 +8,6 @@ import (
 	"testing"
 
 	formsapi "google.golang.org/api/forms/v1"
-	"google.golang.org/api/option"
 )
 
 func newFormsRawTestServer(t *testing.T, status int, body map[string]any) *httptest.Server {
@@ -33,18 +31,8 @@ func newFormsRawTestServer(t *testing.T, status int, body map[string]any) *httpt
 
 func installMockFormsService(t *testing.T, srv *httptest.Server) {
 	t.Helper()
-	orig := newFormsService
-	t.Cleanup(func() { newFormsService = orig })
-
-	svc, err := formsapi.NewService(context.Background(),
-		option.WithoutAuthentication(),
-		option.WithHTTPClient(srv.Client()),
-		option.WithEndpoint(srv.URL+"/"),
-	)
-	if err != nil {
-		t.Fatalf("NewService: %v", err)
-	}
-	newFormsService = func(context.Context, string) (*formsapi.Service, error) { return svc, nil }
+	svc := newGoogleTestServiceWithEndpoint(t, srv.Client(), srv.URL+"/", formsapi.NewService)
+	stubGoogleTestService(t, &newFormsService, svc)
 }
 
 func fullFormResponse(id string) map[string]any {
diff --git a/internal/cmd/gmail_raw_test.go b/internal/cmd/gmail_raw_test.go
index e7b2b8a..c33c78a 100644
--- a/internal/cmd/gmail_raw_test.go
+++ b/internal/cmd/gmail_raw_test.go
@@ -1,7 +1,6 @@
 package cmd
 
 import (
-	"context"
 	"encoding/json"
 	"net/http"
 	"net/http/httptest"
@@ -10,7 +9,6 @@ import (
 	"testing"
 
 	"google.golang.org/api/gmail/v1"
-	"google.golang.org/api/option"
 )
 
 type gmailRawHit struct {
@@ -41,18 +39,8 @@ func newGmailRawTestServer(t *testing.T, status int, body map[string]any, hit *g
 
 func installMockGmailService(t *testing.T, srv *httptest.Server) {
 	t.Helper()
-	orig := newGmailService
-	t.Cleanup(func() { newGmailService = orig })
-
-	svc, err := gmail.NewService(context.Background(),
-		option.WithoutAuthentication(),
-		option.WithHTTPClient(srv.Client()),
-		option.WithEndpoint(srv.URL+"/"),
-	)
-	if err != nil {
-		t.Fatalf("NewService: %v", err)
-	}
-	newGmailService = func(context.Context, string) (*gmail.Service, error) { return svc, nil }
+	svc := newGoogleTestServiceWithEndpoint(t, srv.Client(), srv.URL+"/", gmail.NewService)
+	stubGoogleTestService(t, &newGmailService, svc)
 }
 
 func fullGmailMessageResponse(id string) map[string]any {
diff --git a/internal/cmd/gmail_testutil_test.go b/internal/cmd/gmail_testutil_test.go
index 035919b..5be279a 100644
--- a/internal/cmd/gmail_testutil_test.go
+++ b/internal/cmd/gmail_testutil_test.go
@@ -1,34 +1,19 @@
 package cmd
 
 import (
-	"context"
 	"net/http"
-	"net/http/httptest"
 	"testing"
 
 	"google.golang.org/api/gmail/v1"
-	"google.golang.org/api/option"
 )
 
 func newGmailServiceForTest(t *testing.T, h http.HandlerFunc) (*gmail.Service, func()) {
 	t.Helper()
 
-	srv := httptest.NewServer(h)
-	svc, err := gmail.NewService(context.Background(),
-		option.WithoutAuthentication(),
-		option.WithHTTPClient(srv.Client()),
-		option.WithEndpoint(srv.URL+"/"),
-	)
-	if err != nil {
-		srv.Close()
-		t.Fatalf("NewService: %v", err)
-	}
-	return svc, srv.Close
+	return newGoogleTestService(t, h, gmail.NewService)
 }
 
 func stubGmailServiceForTest(t *testing.T, svc *gmail.Service) {
 	t.Helper()
-	origNew := newGmailService
-	t.Cleanup(func() { newGmailService = origNew })
-	newGmailService = func(context.Context, string) (*gmail.Service, error) { return svc, nil }
+	stubGoogleTestService(t, &newGmailService, svc)
 }
diff --git a/internal/cmd/google_service_testutil_test.go b/internal/cmd/google_service_testutil_test.go
new file mode 100644
index 0000000..19cca3a
--- /dev/null
+++ b/internal/cmd/google_service_testutil_test.go
@@ -0,0 +1,47 @@
+package cmd
+
+import (
+	"context"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"google.golang.org/api/option"
+)
+
+type googleTestServiceFactory[T any] func(context.Context, ...option.ClientOption) (*T, error)
+
+func newGoogleTestService[T any](t *testing.T, h http.Handler, factory googleTestServiceFactory[T]) (*T, func()) {
+	t.Helper()
+
+	srv := httptest.NewServer(h)
+	svc := newGoogleTestServiceWithEndpoint(t, srv.Client(), srv.URL+"/", factory)
+	return svc, srv.Close
+}
+
+func newGoogleTestServiceWithEndpoint[T any](
+	t *testing.T,
+	client *http.Client,
+	endpoint string,
+	factory googleTestServiceFactory[T],
+) *T {
+	t.Helper()
+
+	svc, err := factory(context.Background(),
+		option.WithoutAuthentication(),
+		option.WithHTTPClient(client),
+		option.WithEndpoint(endpoint),
+	)
+	if err != nil {
+		t.Fatalf("NewService: %v", err)
+	}
+	return svc
+}
+
+func stubGoogleTestService[T any](t *testing.T, target *func(context.Context, string) (*T, error), svc *T) {
+	t.Helper()
+
+	orig := *target
+	t.Cleanup(func() { *target = orig })
+	*target = func(context.Context, string) (*T, error) { return svc, nil }
+}
diff --git a/internal/cmd/people_raw_test.go b/internal/cmd/people_raw_test.go
index 248bd6e..eaf813f 100644
--- a/internal/cmd/people_raw_test.go
+++ b/internal/cmd/people_raw_test.go
@@ -1,14 +1,12 @@
 package cmd
 
 import (
-	"context"
 	"encoding/json"
 	"net/http"
 	"net/http/httptest"
 	"strings"
 	"testing"
 
-	"google.golang.org/api/option"
 	"google.golang.org/api/people/v1"
 )
 
@@ -33,18 +31,8 @@ func newPeopleRawTestServer(t *testing.T, status int, body map[string]any) *http
 
 func installMockPeopleContactsService(t *testing.T, srv *httptest.Server) {
 	t.Helper()
-	orig := newPeopleContactsService
-	t.Cleanup(func() { newPeopleContactsService = orig })
-
-	svc, err := people.NewService(context.Background(),
-		option.WithoutAuthentication(),
-		option.WithHTTPClient(srv.Client()),
-		option.WithEndpoint(srv.URL+"/"),
-	)
-	if err != nil {
-		t.Fatalf("NewService: %v", err)
-	}
-	newPeopleContactsService = func(context.Context, string) (*people.Service, error) { return svc, nil }
+	svc := newGoogleTestServiceWithEndpoint(t, srv.Client(), srv.URL+"/", people.NewService)
+	stubGoogleTestService(t, &newPeopleContactsService, svc)
 }
 
 func fullPersonResponse(id string) map[string]any {
diff --git a/internal/cmd/sheets_raw_test.go b/internal/cmd/sheets_raw_test.go
index c489aa0..da469c7 100644
--- a/internal/cmd/sheets_raw_test.go
+++ b/internal/cmd/sheets_raw_test.go
@@ -11,7 +11,6 @@ import (
 	"sync/atomic"
 	"testing"
 
-	"google.golang.org/api/option"
 	"google.golang.org/api/sheets/v4"
 
 	"github.com/steipete/gogcli/internal/ui"
@@ -47,18 +46,8 @@ func newSheetsRawTestServer(t *testing.T, status int, body map[string]any, hit *
 
 func installMockSheetsService(t *testing.T, srv *httptest.Server) {
 	t.Helper()
-	orig := newSheetsService
-	t.Cleanup(func() { newSheetsService = orig })
-
-	svc, err := sheets.NewService(context.Background(),
-		option.WithoutAuthentication(),
-		option.WithHTTPClient(srv.Client()),
-		option.WithEndpoint(srv.URL+"/"),
-	)
-	if err != nil {
-		t.Fatalf("NewService: %v", err)
-	}
-	newSheetsService = func(context.Context, string) (*sheets.Service, error) { return svc, nil }
+	svc := newGoogleTestServiceWithEndpoint(t, srv.Client(), srv.URL+"/", sheets.NewService)
+	stubGoogleTestService(t, &newSheetsService, svc)
 }
 
 func fullSheetResponse(id string) map[string]any {
diff --git a/internal/cmd/slides_raw_test.go b/internal/cmd/slides_raw_test.go
index 15c190a..7ef1e51 100644
--- a/internal/cmd/slides_raw_test.go
+++ b/internal/cmd/slides_raw_test.go
@@ -1,14 +1,12 @@
 package cmd
 
 import (
-	"context"
 	"encoding/json"
 	"net/http"
 	"net/http/httptest"
 	"strings"
 	"testing"
 
-	"google.golang.org/api/option"
 	"google.golang.org/api/slides/v1"
 )
 
@@ -35,18 +33,8 @@ func newSlidesRawTestServer(t *testing.T, status int, body map[string]any) *http
 
 func installMockSlidesService(t *testing.T, srv *httptest.Server) {
 	t.Helper()
-	orig := newSlidesService
-	t.Cleanup(func() { newSlidesService = orig })
-
-	svc, err := slides.NewService(context.Background(),
-		option.WithoutAuthentication(),
-		option.WithHTTPClient(srv.Client()),
-		option.WithEndpoint(srv.URL+"/"),
-	)
-	if err != nil {
-		t.Fatalf("NewService: %v", err)
-	}
-	newSlidesService = func(context.Context, string) (*slides.Service, error) { return svc, nil }
+	svc := newGoogleTestServiceWithEndpoint(t, srv.Client(), srv.URL+"/", slides.NewService)
+	stubGoogleTestService(t, &newSlidesService, svc)
 }
 
 func fullPresentationResponse(id string) map[string]any {
diff --git a/internal/cmd/tasks_raw_test.go b/internal/cmd/tasks_raw_test.go
index f460d3c..4e55a0d 100644
--- a/internal/cmd/tasks_raw_test.go
+++ b/internal/cmd/tasks_raw_test.go
@@ -1,14 +1,12 @@
 package cmd
 
 import (
-	"context"
 	"encoding/json"
 	"net/http"
 	"net/http/httptest"
 	"strings"
 	"testing"
 
-	"google.golang.org/api/option"
 	"google.golang.org/api/tasks/v1"
 )
 
@@ -39,18 +37,8 @@ func newTasksRawTestServer(t *testing.T, status int, body map[string]any) *httpt
 
 func installMockTasksService(t *testing.T, srv *httptest.Server) {
 	t.Helper()
-	orig := newTasksService
-	t.Cleanup(func() { newTasksService = orig })
-
-	svc, err := tasks.NewService(context.Background(),
-		option.WithoutAuthentication(),
-		option.WithHTTPClient(srv.Client()),
-		option.WithEndpoint(srv.URL+"/"),
-	)
-	if err != nil {
-		t.Fatalf("NewService: %v", err)
-	}
-	newTasksService = func(context.Context, string) (*tasks.Service, error) { return svc, nil }
+	svc := newGoogleTestServiceWithEndpoint(t, srv.Client(), srv.URL+"/", tasks.NewService)
+	stubGoogleTestService(t, &newTasksService, svc)
 }
 
 func fullTaskResponse(id string) map[string]any {