Replace deprecated os.Is{Not,}Exist calls

This commit replaces deprecated calls to `os.Is{Not,}Exist` with the
newer `errors.Is(err, fs.Err{Not,}Exist)`.

pkg/fsx/copy.go

@@ -141,7 +141,7 @@ func CopyDirectory(ctx context.Context, dst, src string, onCopy func(dst, src st
 		// create the directory, but ignore an error if the directory already exists.
 		// this is so that we can copy one tree into another tree.
 		err = Mkdir(dst, info.Mode())
-		if os.IsExist(err) && IsDirectory(dst) {
+		if errors.Is(err, fs.ErrExist) && IsDirectory(dst) {
 			err = nil
 		}
 

pkg/fsx/create.go

@@ -1,6 +1,7 @@
 package fsx
 
 import (
+	"errors"
 	"io/fs"
 	"os"
 	"time"
@@ -40,7 +41,7 @@ func Touch(path string, perm fs.FileMode) error {
 	}
 	_, err := os.Stat(path)
 	switch {
-	case os.IsNotExist(err):
+	case errors.Is(err, fs.ErrNotExist):
 		f, err := Create(path, perm)
 		if err != nil {
 			return err

pkg/fsx/same.go

@@ -1,6 +1,8 @@
 package fsx
 
 import (
+	"errors"
+	"io/fs"
 	"os"
 	"path/filepath"
 )
@@ -60,7 +62,7 @@ func couldBeSameFile(path1, path2 string) (same, authorative bool) {
 		}
 
 		// only 1 file does not exist => they could be different
-		if os.IsNotExist(err1) != os.IsNotExist(err2) {
+		if errors.Is(err1, fs.ErrNotExist) != errors.Is(err2, fs.ErrNotExist) {
 			return
 		}
 	}

pkg/unpack/resource.go

@@ -83,7 +83,7 @@ func installDir(dst string, srcInfo fs.FileInfo, srcFile fs.ReadDirFile, src str
 	// create the destination
 	dstStat, dstErr := os.Stat(dst)
 	switch {
-	case os.IsNotExist(dstErr):
+	case errors.Is(dstErr, fs.ErrNotExist):
 		if err := fsx.MkdirAll(dst, srcInfo.Mode()); err != nil {
 			return errors.Wrapf(err, "Error creating destination directory %s", dst)
 		}