fix: worked around windows-specific data race issue in tests

Signed-off-by: Frederic BIDON <fredbi@yahoo.com>

Author: fredbi

circular_test.go

@@ -6,7 +6,6 @@ package spec
 import (
 	"encoding/json"
 	"net/http"
-	"net/http/httptest"
 	"os"
 	"path/filepath"
 	"testing"
@@ -255,8 +254,7 @@ func TestExpandCircular_RemoteCircularID(t *testing.T) {
 func TestCircular_RemoteExpandAzure(t *testing.T) {
 	// local copy of Azure publicIpAddress.json from azure-rest-api-specs
 	// (Microsoft.Network/stable/2020-04-01)
-	server := httptest.NewServer(http.FileServer(http.Dir("fixtures/azure")))
-	defer server.Close()
+	server := fixtureServer(t, "fixtures/azure")
 
 	basePath := server.URL + "/publicIpAddress.json"
 	jazon, sch := expandThisOrDieTrying(t, basePath)

expander_test.go

@@ -29,7 +29,7 @@ const (
 
 //nolint:gochecknoglobals // it's okay to have embedded test fixtures as globals
 var (
-	//go:embed fixtures/*/*.json fixtures/*/*.yaml fixtures/*/*.yml
+	//go:embed all:fixtures
 	fixtureAssets embed.FS
 
 	// PetStore20 json doc for swagger 2.0 pet store.
@@ -749,8 +749,7 @@ func TestExpand_InternalSchemas1(t *testing.T) {
 }
 
 func TestExpand_RelativeBaseURI(t *testing.T) {
-	server := httptest.NewServer(http.FileServer(http.Dir("fixtures/remote")))
-	defer server.Close()
+	server := fixtureServer(t, "fixtures/remote")
 
 	spec := new(Swagger)
 

helpers_test.go

@@ -6,6 +6,9 @@ package spec
 import (
 	"encoding/json"
 	"fmt"
+	"io/fs"
+	"net/http"
+	"net/http/httptest"
 	"regexp"
 	"strings"
 	"testing"
@@ -17,6 +20,22 @@ import (
 
 var rex = regexp.MustCompile(`"\$ref":\s*"(.*?)"`)
 
+// fixtureServer returns an httptest.Server serving the given subdirectory
+// from the embedded fixtureAssets FS. This avoids OS-level file serving
+// (and the Windows TransmitFile/sendfile code path that has a data race
+// in Go 1.26).
+func fixtureServer(t testing.TB, dir string) *httptest.Server {
+	t.Helper()
+
+	sub, err := fs.Sub(fixtureAssets, dir)
+	require.NoError(t, err)
+
+	server := httptest.NewServer(http.FileServerFS(sub))
+	t.Cleanup(server.Close)
+
+	return server
+}
+
 func jsonDoc(path string) (json.RawMessage, error) {
 	data, err := loading.LoadFromFileOrHTTP(path)
 	if err != nil {

resolver_test.go

@@ -5,8 +5,6 @@ package spec
 
 import (
 	"encoding/json"
-	"net/http"
-	"net/http/httptest"
 	"os"
 	"path/filepath"
 	"testing"
@@ -130,9 +128,7 @@ func TestResolveParamWithBase(t *testing.T) {
 }
 
 func TestResolveRemoteRef_RootSame(t *testing.T) {
-	fileserver := http.FileServer(http.Dir(specs))
-	server := httptest.NewServer(fileserver)
-	defer server.Close()
+	server := fixtureServer(t, specs)
 
 	rootDoc := new(Swagger)
 	b, err := os.ReadFile(filepath.Join(specs, "refed.json"))
@@ -158,9 +154,7 @@ func TestResolveRemoteRef_RootSame(t *testing.T) {
 }
 
 func TestResolveRemoteRef_FromFragment(t *testing.T) {
-	fileserver := http.FileServer(http.Dir(specs))
-	server := httptest.NewServer(fileserver)
-	defer server.Close()
+	server := fixtureServer(t, specs)
 
 	rootDoc := new(Swagger)
 	b, err := os.ReadFile(filepath.Join(specs, "refed.json"))
@@ -178,9 +172,7 @@ func TestResolveRemoteRef_FromFragment(t *testing.T) {
 }
 
 func TestResolveRemoteRef_FromInvalidFragment(t *testing.T) {
-	fileserver := http.FileServer(http.Dir(specs))
-	server := httptest.NewServer(fileserver)
-	defer server.Close()
+	server := fixtureServer(t, specs)
 
 	rootDoc := new(Swagger)
 	b, err := os.ReadFile(filepath.Join(specs, "refed.json"))
@@ -215,9 +207,7 @@ func TestResolveRemoteRef_FromInvalidFragment(t *testing.T) {
 // }
 
 func TestResolveRemoteRef_ToParameter(t *testing.T) {
-	fileserver := http.FileServer(http.Dir(specs))
-	server := httptest.NewServer(fileserver)
-	defer server.Close()
+	server := fixtureServer(t, specs)
 
 	rootDoc := new(Swagger)
 	b, err := os.ReadFile(filepath.Join(specs, "refed.json"))
@@ -240,9 +230,7 @@ func TestResolveRemoteRef_ToParameter(t *testing.T) {
 }
 
 func TestResolveRemoteRef_ToPathItem(t *testing.T) {
-	fileserver := http.FileServer(http.Dir(specs))
-	server := httptest.NewServer(fileserver)
-	defer server.Close()
+	server := fixtureServer(t, specs)
 
 	rootDoc := new(Swagger)
 	b, err := os.ReadFile(filepath.Join(specs, "refed.json"))
@@ -259,9 +247,7 @@ func TestResolveRemoteRef_ToPathItem(t *testing.T) {
 }
 
 func TestResolveRemoteRef_ToResponse(t *testing.T) {
-	fileserver := http.FileServer(http.Dir(specs))
-	server := httptest.NewServer(fileserver)
-	defer server.Close()
+	server := fixtureServer(t, specs)
 
 	rootDoc := new(Swagger)
 	b, err := os.ReadFile(filepath.Join(specs, "refed.json"))