diff --git a/generator/internal/sidekick/cmdline_test.go b/generator/internal/sidekick/cmdline_test.go
index 245c50060..51c8e6626 100644
--- a/generator/internal/sidekick/cmdline_test.go
+++ b/generator/internal/sidekick/cmdline_test.go
@@ -15,6 +15,7 @@
 package sidekick
 
 import (
+	"fmt"
 	"testing"
 
 	"github.com/google/go-cmp/cmp"
@@ -24,11 +25,11 @@ func TestParseArgs(t *testing.T) {
 	args := []string{
 		"-project-root", "../..",
 		"-specification-format", "openapi",
-		"-specification-source", "generator/testdata/openapi/secretmanager_openapi_v1.json",
-		"-service-config", "generator/testdata/googleapis/google/cloud/secretmanager/v1/secretmanager_v1.yaml",
-		"-source-option", "googleapis-root=generator/testdata/googleapis",
+		"-specification-source", specificationSource,
+		"-service-config", secretManagerServiceConfig,
+		"-source-option", fmt.Sprintf("googleapis-root=%s", googleapisRoot),
 		"-language", "rust",
-		"-output", "generator/testdata/test-only",
+		"-output", outputDir,
 		"-template-dir", "generator/templates",
 		"-codec-option", "copyright-year=2024",
 		"-codec-option", "package-name-override=secretmanager-golden-openapi",
@@ -45,14 +46,14 @@ func TestParseArgs(t *testing.T) {
 		Command:             "generate",
 		ProjectRoot:         "../..",
 		SpecificationFormat: "openapi",
-		SpecificationSource: "generator/testdata/openapi/secretmanager_openapi_v1.json",
-		ServiceConfig:       "generator/testdata/googleapis/google/cloud/secretmanager/v1/secretmanager_v1.yaml",
+		SpecificationSource: specificationSource,
+		ServiceConfig:       secretManagerServiceConfig,
 		Source: map[string]string{
-			"googleapis-root": "generator/testdata/googleapis",
+			"googleapis-root": googleapisRoot,
 		},
 		Language:    "rust",
-		Output:      "generator/testdata/test-only",
-		TemplateDir: "generator/templates",
+		Output:      outputDir,
+		TemplateDir: templateDir,
 		Codec: map[string]string{
 			"copyright-year":            "2024",
 			"package-name-override":     "secretmanager-golden-openapi",
diff --git a/generator/internal/sidekick/sidekick_test.go b/generator/internal/sidekick/sidekick_test.go
index 661fd4804..fe3b74c3d 100644
--- a/generator/internal/sidekick/sidekick_test.go
+++ b/generator/internal/sidekick/sidekick_test.go
@@ -20,6 +20,7 @@ import (
 	"os"
 	"os/exec"
 	"path"
+	"path/filepath"
 	"sort"
 	"strings"
 	"testing"
@@ -29,20 +30,29 @@ const (
 	// projectRoot is the root of the google-cloud-rust. The golden files for
 	// these tests depend on code in ../../auth and ../../src/gax.
 	projectRoot = "../../.."
+	templateDir = "generator/templates"
 	testdataDir = "generator/testdata"
 )
 
+var (
+	googleapisRoot             = fmt.Sprintf("%s/googleapis", testdataDir)
+	outputDir                  = fmt.Sprintf("%s/test-only", testdataDir)
+	secretManagerServiceConfig = "googleapis/google/cloud/secretmanager/v1/secretmanager_v1.yaml"
+	specificationSource        = fmt.Sprintf("%s/openapi/secretmanager_openapi_v1.json", testdataDir)
+	testdataImportPath         = fmt.Sprintf("github.com/google-cloud-rust/%s", testdataDir)
+)
+
 func TestRustFromOpenAPI(t *testing.T) {
 	var outDir = fmt.Sprintf("%s/rust/openapi/golden", testdataDir)
 	cmdLine := &CommandLine{
 		Command:             "generate",
 		ProjectRoot:         projectRoot,
 		SpecificationFormat: "openapi",
-		SpecificationSource: "generator/testdata/openapi/secretmanager_openapi_v1.json",
-		ServiceConfig:       "generator/testdata/googleapis/google/cloud/secretmanager/v1/secretmanager_v1.yaml",
+		SpecificationSource: specificationSource,
+		ServiceConfig:       fmt.Sprintf("%s/%s", testdataDir, secretManagerServiceConfig),
 		Language:            "rust",
 		Output:              outDir,
-		TemplateDir:         "generator/templates",
+		TemplateDir:         templateDir,
 		Codec: map[string]string{
 			"copyright-year":            "2024",
 			"package-name-override":     "secretmanager-golden-openapi",
@@ -69,46 +79,51 @@ func TestRustFromProtobuf(t *testing.T) {
 
 	configs := []TestConfig{
 		{
-			Source:        "generator/testdata/googleapis/google/type",
-			ServiceConfig: "generator/testdata/googleapis/google/type/type.yaml",
+			Source:        "googleapis/google/type",
+			ServiceConfig: "googleapis/google/type/type.yaml",
 			Name:          "type",
 		},
 		{
-			Source:        "generator/testdata/googleapis/google/cloud/location",
-			ServiceConfig: "generator/testdata/googleapis/google/cloud/location/cloud.yaml",
+			Source:        "googleapis/google/cloud/location",
+			ServiceConfig: "googleapis/google/cloud/location/cloud.yaml",
 			Name:          "location",
 		},
 		{
-			Source: "generator/testdata/googleapis/google/iam/v1",
+			Source: "googleapis/google/iam/v1",
 			Name:   "iam/v1",
 			ExtraOptions: map[string]string{
-				"package:gtype": "package=type-golden-gclient,path=generator/testdata/rust/gclient/golden/type,source=google.type",
+				"package:gtype": fmt.Sprintf("package=type-golden-gclient,path=%s/rust/gclient/golden/type,source=google.type", testdataDir),
 			},
 		},
 		{
-			Source:        "generator/testdata/googleapis/google/cloud/secretmanager/v1",
-			ServiceConfig: "generator/testdata/googleapis/google/cloud/secretmanager/v1/secretmanager_v1.yaml",
+			Source:        "googleapis/google/cloud/secretmanager/v1",
+			ServiceConfig: secretManagerServiceConfig,
 			Name:          "secretmanager",
 			ExtraOptions: map[string]string{
-				"package:iam":      "package=iam-v1-golden-gclient,path=generator/testdata/rust/gclient/golden/iam/v1,source=google.iam.v1",
-				"package:location": "package=location-golden-gclient,path=generator/testdata/rust/gclient/golden/location,source=google.cloud.location",
+				"package:iam":      fmt.Sprintf("package=iam-v1-golden-gclient,path=%s/rust/gclient/golden/iam/v1,source=google.iam.v1", testdataDir),
+				"package:location": fmt.Sprintf("package=location-golden-gclient,path=%s/rust/gclient/golden/location,source=google.cloud.location", testdataDir),
 			},
 		},
 	}
-
 	for _, config := range configs {
+		if config.Source != "" {
+			config.Source = filepath.Join(testdataDir, config.Source)
+		}
+		if config.ServiceConfig != "" {
+			config.ServiceConfig = filepath.Join(testdataDir, config.ServiceConfig)
+		}
 		cmdLine := &CommandLine{
 			Command:             "generate",
 			ProjectRoot:         projectRoot,
 			SpecificationFormat: "protobuf",
 			SpecificationSource: config.Source,
 			Source: map[string]string{
-				"googleapis-root": "generator/testdata/googleapis",
+				"googleapis-root": googleapisRoot,
 			},
 			ServiceConfig: config.ServiceConfig,
 			Language:      "rust",
 			Output:        path.Join(outDir, config.Name),
-			TemplateDir:   "generator/templates",
+			TemplateDir:   templateDir,
 			Codec: map[string]string{
 				"copyright-year":            "2024",
 				"package-name-override":     strings.Replace(config.Name, "/", "-", -1) + "-golden-gclient",
@@ -165,12 +180,12 @@ func TestRustModuleFromProtobuf(t *testing.T) {
 			SpecificationFormat: "protobuf",
 			SpecificationSource: config.Source,
 			Source: map[string]string{
-				"googleapis-root": "generator/testdata/googleapis",
+				"googleapis-root": googleapisRoot,
 			},
 			ServiceConfig: config.ServiceConfig,
 			Language:      "rust",
-			Output:        path.Join("generator/testdata/rust/gclient/golden/module", config.Name),
-			TemplateDir:   "generator/templates",
+			Output:        path.Join(testdataDir, "rust/gclient/golden/module", config.Name),
+			TemplateDir:   templateDir,
 			Codec: map[string]string{
 				"copyright-year":  "2024",
 				"generate-module": "true",
@@ -195,23 +210,23 @@ func TestGoFromProtobuf(t *testing.T) {
 	}
 	configs := []TestConfig{
 		{
-			Source: "generator/testdata/googleapis/google/type",
+			Source: fmt.Sprintf("%s/google/type", googleapisRoot),
 			Name:   "typez",
 			ExtraOptions: map[string]string{
 				"go-package-name": "typez",
 			},
 		},
 		{
-			Source: "generator/testdata/googleapis/google/iam/v1",
+			Source: fmt.Sprintf("%s/google/iam/v1", googleapisRoot),
 			Name:   "iam/v1",
 			ExtraOptions: map[string]string{
-				"import-mapping:google.type":     "github.com/google-cloud-rust/generator/testdata/go/gclient/golden/typez;typez",
-				"import-mapping:google.protobuf": "github.com/google-cloud-rust/generator/testdata/go/gclient/golden/wkt;wkt",
+				"import-mapping:google.type":     fmt.Sprintf("%s/go/gclient/golden/typez;typez", testdataImportPath),
+				"import-mapping:google.protobuf": fmt.Sprintf("%s/go/gclient/golden/wkt;wkt", testdataImportPath),
 				"go-package-name":                "iam",
 			},
 			ModReplace: map[string]string{
-				"github.com/google-cloud-rust/generator/testdata/go/gclient/golden/typez": "typez",
-				"github.com/google-cloud-rust/generator/testdata/go/gclient/golden/wkt":   "wkt",
+				fmt.Sprintf("%s/go/gclient/golden/typez", testdataImportPath): "typez",
+				fmt.Sprintf("%s/go/gclient/golden/wkt", testdataImportPath):   "wkt",
 			},
 		},
 	}
@@ -223,15 +238,15 @@ func TestGoFromProtobuf(t *testing.T) {
 			SpecificationFormat: "protobuf",
 			SpecificationSource: config.Source,
 			Source: map[string]string{
-				"googleapis-root": "generator/testdata/googleapis",
+				"googleapis-root": googleapisRoot,
 			},
 			ServiceConfig: "",
 			Language:      "go",
 			Output:        path.Join(outDir, config.Name),
-			TemplateDir:   "generator/templates",
+			TemplateDir:   templateDir,
 			Codec: map[string]string{
 				"copyright-year":        "2024",
-				"package-name-override": "github.com/google-cloud-rust/generator/testdata/go/gclient/golden/" + config.Name,
+				"package-name-override": fmt.Sprintf("%s/go/gclient/golden/%s", testdataImportPath, config.Name),
 			},
 		}
 		for k, v := range config.ExtraOptions {