go/src/io/fs/walk_test.go

type Node …

var tree …

func walkTree(n *Node, path string, f func(path string, n *Node)) { … }

func makeTree() FS { … }

// Assumes that each node name is unique. Good enough for a test.
// If clear is true, any incoming error is cleared before return. The errors
// are always accumulated, though.
func mark(entry DirEntry, err error, errors *[]error, clear bool) error { … }

func TestWalkDir(t *testing.T) { … }

func TestIssue51617(t *testing.T) { … }