2022-11-14 15:41:57 +05:30

139 lines
3.3 KiB
Go

// License: GPLv3 Copyright: 2022, Kovid Goyal, <kovid at kovidgoyal.net>
package completion
import (
"fmt"
"io/fs"
"os"
"path/filepath"
"strings"
"golang.org/x/sys/unix"
)
var _ = fmt.Print
type CompleteFilesCallback func(completion_candidate, abspath string, d fs.DirEntry) error
type Walk_callback func(path string, d fs.DirEntry, err error) error
func transform_symlink(path string) string {
if q, err := filepath.EvalSymlinks(path); err == nil {
return q
}
return path
}
func needs_symlink_recurse(path string, d fs.DirEntry) bool {
if d.Type()&os.ModeSymlink == os.ModeSymlink {
if s, serr := os.Stat(path); serr == nil && s.IsDir() {
return true
}
}
return false
}
type transformed_walker struct {
seen map[string]bool
real_callback Walk_callback
transform_func func(string) string
needs_recurse_func func(string, fs.DirEntry) bool
}
func (self *transformed_walker) walk(dirpath string) error {
resolved_path := self.transform_func(dirpath)
if self.seen[resolved_path] {
return nil
}
self.seen[resolved_path] = true
c := func(path string, d fs.DirEntry, err error) error {
if err != nil {
// Happens if ReadDir on d failed, skip it in that case
return fs.SkipDir
}
rpath, err := filepath.Rel(resolved_path, path)
if err != nil {
return err
}
path_based_on_original_dir := filepath.Join(dirpath, rpath)
if self.needs_recurse_func(path, d) {
err = self.walk(path_based_on_original_dir)
} else {
err = self.real_callback(path_based_on_original_dir, d, err)
}
return err
}
return filepath.WalkDir(resolved_path, c)
}
// Walk, recursing into symlinks that point to directories. Ignores directories
// that could not be read.
func WalkWithSymlink(dirpath string, callback Walk_callback) error {
sw := transformed_walker{
seen: make(map[string]bool), real_callback: callback, transform_func: transform_symlink, needs_recurse_func: needs_symlink_recurse}
return sw.walk(dirpath)
}
func complete_files(prefix string, callback CompleteFilesCallback) error {
base := "."
has_cwd_prefix := strings.HasPrefix(prefix, "./")
is_abs_path := filepath.IsAbs(prefix)
wd := ""
if is_abs_path {
base = prefix
if s, err := os.Stat(prefix); err != nil || !s.IsDir() {
base = filepath.Dir(prefix)
}
} else {
var qe error
wd, qe = os.Getwd()
if qe != nil {
wd = ""
}
}
num := 0
WalkWithSymlink(base, func(path string, d fs.DirEntry, err error) error {
if err != nil {
return fs.SkipDir
}
num++
if num == 1 {
return nil
}
completion_candidate := path
abspath := path
if !is_abs_path {
abspath = filepath.Join(wd, path)
if has_cwd_prefix {
completion_candidate = "./" + completion_candidate
}
}
if strings.HasPrefix(completion_candidate, prefix) {
return callback(completion_candidate, abspath, d)
}
return nil
})
return nil
}
func complete_executables_in_path(prefix string, paths ...string) []string {
ans := make([]string, 0, 1024)
if len(paths) == 0 {
paths = filepath.SplitList(os.Getenv("PATH"))
}
for _, dir := range paths {
entries, err := os.ReadDir(dir)
if err == nil {
for _, e := range entries {
if strings.HasPrefix(e.Name(), prefix) && !e.IsDir() && unix.Access(filepath.Join(dir, e.Name()), unix.X_OK) == nil {
ans = append(ans, e.Name())
}
}
}
}
return ans
}