Test that a manifest's namespace mounts its source under a dot path, that each shipped module loads from data/<lowered namespace>, and that a load failure's note reaches Fake, FakeTemplate and FakeStruct once

fejkdata_test.go

@@ -3,6 +3,8 @@ package fejkdata
 import (
 	"errors"
 	"io/fs"
+	"os"
+	"path/filepath"
 	"strings"
 	"testing"
 	"testing/fstest"
@@ -35,6 +37,17 @@ func newGeneratorN(t *testing.T, dirs []string, opts ...Option) *Generator {
 	return f
 }
 
+// newBareModule loads the shipped module in data/<module> without its manifest, so its
+// categories sit at the root, failing on error.
+func newBareModule(t *testing.T, module string, opts ...Option) *Generator {
+	t.Helper()
+	f, err := New(append([]Option{WithDataFS(withoutManifest{os.DirFS(filepath.Join("data", module))})}, opts...)...)
+	if err != nil {
+		t.Fatalf("New(%s without its manifest): %v", module, err)
+	}
+	return f
+}
+
 // fake generates a value, failing the test on error.
 func fake(t *testing.T, f *Generator, path string) string {
 	t.Helper()