lsp: Add test for server templating

Signed-off-by: Charlie Egan <charlie@styra.com>

internal/lsp/server.go

@@ -1757,7 +1757,7 @@ func (l *LanguageServer) handleTextDocumentFormatting(
 	}
 
 	// if the file is empty, then the formatters will fail, so we template
-	// intstead
+	// instead
 	if oldContent == "" {
 		newContent, err := l.templateContentsForFile(params.TextDocument.URI)
 		if err != nil {

internal/lsp/server_template_test.go

@@ -0,0 +1,58 @@
+package lsp
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/styrainc/regal/internal/lsp/clients"
+	"github.com/styrainc/regal/internal/lsp/uri"
+)
+
+func TestServerTemplateContentsForFile(t *testing.T) {
+	t.Parallel()
+
+	s := NewLanguageServer(
+		&LanguageServerOptions{
+			ErrorLog: os.Stderr,
+		},
+	)
+
+	td := t.TempDir()
+
+	filePath := filepath.Join(td, "foo/bar/baz.rego")
+	regalPath := filepath.Join(td, ".regal/config.yaml")
+
+	initialState := map[string]string{
+		filePath:  "",
+		regalPath: "",
+	}
+
+	// create the initial state needed for the regal config root detection
+	for file := range initialState {
+		fileDir := filepath.Dir(file)
+
+		err := os.MkdirAll(fileDir, 0o755)
+		if err != nil {
+			t.Fatalf("unexpected error: %v", err)
+		}
+
+		err = os.WriteFile(file, []byte(""), 0o600)
+		if err != nil {
+			t.Fatalf("unexpected error: %v", err)
+		}
+	}
+
+	fileURI := uri.FromPath(clients.IdentifierGeneric, filePath)
+
+	s.cache.SetFileContents(fileURI, "")
+
+	newContents, err := s.templateContentsForFile(fileURI)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+
+	if newContents != "package foo.bar\n\nimport rego.v1\n" {
+		t.Fatalf("unexpected contents: %v", newContents)
+	}
+}

pkg/config/config.go

@@ -195,7 +195,11 @@ func FindBundleRootDirectories(path string) ([]string, error) {
 
 	// This will traverse the tree **downwards** searching for .regal directories
 	// Not using rio.WalkFiles here as we're specifically looking for directories
-	if err := filepath.WalkDir(path, func(path string, info os.DirEntry, _ error) error {
+	if err := filepath.WalkDir(path, func(path string, info os.DirEntry, err error) error {
+		if err != nil {
+			return fmt.Errorf("failed to walk path: %w", err)
+		}
+
 		if info.IsDir() && info.Name() == regalDirName {
 			// Opening files as part of walking is generally not a good idea...
 			// but I think we can assume the number of .regal directories in a project