Find filesystem objects in Go (Golang) - regex

Question

I am trying to find matching filesystem objects using Go and determine the type of path I received as input. Specifically, I need to perform actions on the object(s) if they match the path provided. Example input for the path could look like this:
/path/to/filename.ext
/path/to/dirname
/path/to/*.txt
I need to know if the path exists, is a file or a directory or a regex so I can process the input accordingly. Here's the solution I've devised so far:
func getPathType(path string) (bool, string, error) {
cpath := filepath.Clean(path)
l, err := filepath.Glob(cpath)
if err != nil {
return false, "", err
}
switch len(l) {
case 0:
return false, "", nil
case 1:
fsstat, fserr := os.Stat(cpath)
if fserr != nil {
return false, "", fserr
}
if fsstat.IsDir() {
return true, "dir", nil
}
return true, "file", nil
default:
return false, "regex", nil
}
}
I realize that the above code would allow a regex that returned a single value to be interpreted as a dir or file and not as a regex. For my purposes, I can let that slide but just curious if anyone has developed a better way of taking a path potentially containing regex as input and determining whether or not the last element is a regex or not.

Answer 1

Test for glob special characters to determine if the path is a glob pattern. Use filepath.Match to check for valid glob pattern syntax.
func getPathType(path string) (bool, string, error) {
cpath := filepath.Clean(path)
// Use Match to check glob syntax.
if _, err := filepath.Match(cpath, ""); err != nil {
return false, "", err
}
// If syntax is good and the path includes special
// glob characters, then it's a glob pattern.
special := `*?[`
if runtime.GOOS != "windows" {
special = `*?[\`
}
if strings.ContainsAny(cpath, special) {
return false, "regex", nil
}
fsstat, err := os.Stat(cpath)
if os.IsNotExist(err) {
return false, "", nil
} else if err != nil {
return false, "", err
}
if fsstat.IsDir() {
return true, "dir", nil
}
return true, "file", nil
}