proper fix

cmd/fs/helpers.go

@@ -35,7 +35,7 @@ func filerForPath(ctx context.Context, fullPath string) (filer.Filer, string, er
 		if runtime.GOOS == "windows" {
 			parts := strings.SplitN(path, ":", 2)
 			if len(parts) < 2 {
-				return nil, "", fmt.Errorf("no volume specfied for path: %s", path)
+				return nil, "", fmt.Errorf("no volume specified for path: %s", path)
 			}
 			volume := parts[0] + ":"
 			relPath := parts[1]

libs/filer/dbfs_client.go

@@ -67,14 +67,14 @@ type DbfsClient struct {
 	workspaceClient *databricks.WorkspaceClient
 
 	// File operations will be relative to this path.
-	root RootPath
+	root UnixRootPath
 }
 
 func NewDbfsClient(w *databricks.WorkspaceClient, root string) (Filer, error) {
 	return &DbfsClient{
 		workspaceClient: w,
 
-		root: NewRootPath(root),
+		root: NewUnixRootPath(root),
 	}, nil
 }
 

libs/filer/local_client.go

@@ -19,12 +19,13 @@ type LocalClient struct {
 
 func NewLocalClient(root string) (Filer, error) {
 	if runtime.GOOS == "windows" && root == "/" {
-		// Windows paths require a Volume/Drive letter specified. This allows us
-		// to create local filers at the root of a windows file system without specifying one
-		return &LocalClient{root: NewRootPath("")}, nil
+		// Windows file systems do not have a "root" directory. Instead paths require
+		// a Volume/Drive letter specified. This allows us to refer to files across
+		// different drives from a single client
+		return &LocalClient{root: NopRootPath{}}, nil
 	}
 	return &LocalClient{
-		root: NewRootPath(root),
+		root: NewUnixRootPath(root),
 	}, nil
 }
 
@@ -106,7 +107,7 @@ func (w *LocalClient) Delete(ctx context.Context, name string, mode ...DeleteMod
 	}
 
 	// Illegal to delete the root path.
-	if absPath == w.root.rootPath {
+	if absPath == w.root.Root() {
 		return CannotDeleteRootError{}
 	}
 

libs/filer/local_client_test.go

@@ -3,17 +3,13 @@ package filer
 import (
 	"context"
 	"path/filepath"
-	"runtime"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
 
-func TestLocalClientAtRootForWindows(t *testing.T) {
-	if runtime.GOOS != "windows" {
-		t.Skip("this test is only meant for windows")
-	}
+func TestLocalClientAtRootOfFilesystem(t *testing.T) {
 	tmpDir := t.TempDir()
 	ctx := context.Background()
 

libs/filer/root_path.go

@@ -1,34 +1,16 @@
 package filer
 
-import (
-	"fmt"
-	"path"
-	"strings"
-)
-
-// RootPath can be joined with a relative path and ensures that
-// the returned path is always a strict child of the root path.
-type RootPath struct {
-	rootPath string
+type RootPath interface {
+	Join(string) (string, error)
+	Root() string
 }
 
-// NewRootPath constructs and returns [RootPath].
-// The named path is cleaned on construction.
-func NewRootPath(name string) RootPath {
-	return RootPath{
-		rootPath: path.Clean(name),
-	}
+type NopRootPath struct{}
+
+func (rp NopRootPath) Join(name string) (string, error) {
+	return name, nil
 }
 
-// Join returns the specified path name joined to the root.
-// It returns an error if the resulting path is not a strict child of the root path.
-func (p *RootPath) Join(name string) (string, error) {
-	absPath := path.Join(p.rootPath, name)
-
-	// Don't allow escaping the specified root using relative paths.
-	if !strings.HasPrefix(absPath, p.rootPath) {
-		return "", fmt.Errorf("relative path escapes root: %s", name)
-	}
-
-	return absPath, nil
+func (rp NopRootPath) Root() string {
+	return ""
 }

libs/filer/unix_root_path.go

@@ -0,0 +1,38 @@
+package filer
+
+import (
+	"fmt"
+	"path"
+	"strings"
+)
+
+// UnixRootPath can be joined with a relative path and ensures that
+// the returned path is always a strict child of the root path.
+type UnixRootPath struct {
+	rootPath string
+}
+
+// NewUnixRootPath constructs and returns [RootPath].
+// The named path is cleaned on construction.
+func NewUnixRootPath(name string) UnixRootPath {
+	return UnixRootPath{
+		rootPath: path.Clean(name),
+	}
+}
+
+// Join returns the specified path name joined to the root.
+// It returns an error if the resulting path is not a strict child of the root path.
+func (p UnixRootPath) Join(name string) (string, error) {
+	absPath := path.Join(p.rootPath, name)
+
+	// Don't allow escaping the specified root using relative paths.
+	if !strings.HasPrefix(absPath, p.rootPath) {
+		return "", fmt.Errorf("relative path escapes root: %s", name)
+	}
+
+	return absPath, nil
+}
+
+func (p UnixRootPath) Root() string {
+	return p.rootPath
+}

libs/filer/unix_root_path_test.go

@@ -7,9 +7,9 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-func testRootPath(t *testing.T, uncleanRoot string) {
+func testUnixRootPath(t *testing.T, uncleanRoot string) {
 	cleanRoot := path.Clean(uncleanRoot)
-	rp := NewRootPath(uncleanRoot)
+	rp := NewUnixRootPath(uncleanRoot)
 
 	remotePath, err := rp.Join("a/b/c")
 	assert.NoError(t, err)
@@ -79,12 +79,12 @@ func testRootPath(t *testing.T, uncleanRoot string) {
 	assert.ErrorContains(t, err, `relative path escapes root: ../..`)
 }
 
-func TestRootPathClean(t *testing.T) {
-	testRootPath(t, "/some/root/path")
+func TestUnixRootPathClean(t *testing.T) {
+	testUnixRootPath(t, "/some/root/path")
 }
 
-func TestRootPathUnclean(t *testing.T) {
-	testRootPath(t, "/some/root/path/")
-	testRootPath(t, "/some/root/path/.")
-	testRootPath(t, "/some/root/../path/")
+func TestUnixRootPathUnclean(t *testing.T) {
+	testUnixRootPath(t, "/some/root/path/")
+	testUnixRootPath(t, "/some/root/path/.")
+	testUnixRootPath(t, "/some/root/../path/")
 }

libs/filer/workspace_files_client.go

@@ -79,7 +79,7 @@ type WorkspaceFilesClient struct {
 	apiClient       *client.DatabricksClient
 
 	// File operations will be relative to this path.
-	root RootPath
+	root UnixRootPath
 }
 
 func NewWorkspaceFilesClient(w *databricks.WorkspaceClient, root string) (Filer, error) {
@@ -92,7 +92,7 @@ func NewWorkspaceFilesClient(w *databricks.WorkspaceClient, root string) (Filer,
 		workspaceClient: w,
 		apiClient:       apiClient,
 
-		root: NewRootPath(root),
+		root: NewUnixRootPath(root),
 	}, nil
 }