find and filter files

find.go

package find

import (
	"os"
	"path/filepath"
	"regexp"
)

// File wraps the os.FileInfo struct to include a path reference
type File struct {
	os.FileInfo
	Path string
}

// Files represents a slice of File structs
type Files []File

// Find returns Files under the given root
func Find(root string) (Files, error) {
	var list = Files{}
	var err error

	if err = filepath.Walk(root, func(p string, f os.FileInfo, err error) error {
		if f != nil {
			list = append(list, File{FileInfo: f, Path: p})
		}
		return nil
	}); err != nil {
		return nil, err
	}

	return list, nil
}

// FilterFiles applies the regex filter against all files in the list
func (f Files) FilterFiles(regex string) (Files, error) {
	return f.filter(regex, false, true)
}

// FilterDirs applies the regex filter against all directories in the list
func (f Files) FilterDirs(regex string) (Files, error) {
	return f.filter(regex, true, false)
}

// Filter applies the regext against all files and directories in the list
func (f Files) Filter(regex string) (Files, error) {
	return f.filter(regex, true, true)
}

// filter returns a filtered list of elements
func (f Files) filter(regex string, dirs bool, files bool) (Files, error) {
	var re *regexp.Regexp
	var out = Files{}
	var err error

	if re, err = regexp.Compile(regex); err != nil {
		return nil, err
	}

	for _, file := range f {
		if !dirs && files && file.IsDir() {
			// we aren't filtering files
			out = append(out, file)
			continue
		}
		if !files && dirs && !file.IsDir() {
			// we aren't filtering directories
			out = append(out, file)
			continue
		}
		if !re.MatchString(file.Path) {
			// it's filtered but didn't match
			out = append(out, file)
		}
	}

	// return filtered output
	return out, nil
}